Presumed normal hemodynamic values of the arteries in the final third period of gestation in bitches

Background: Doppler ultrasonography enables the investigation of vascular blood flow indexes in gestational assessment,being able to detect vascular resistances that can affect fetal and maternal circulation, such as cases of placental insufficiency, associated with fetal cerebral oxygenation deficit and fetal distress. The study aims to assume hemodynamicallynormal values in the final third of gestation in bitches, of the umbilical, uteroplacental, middle cerebral and internal carotidarteries, correlating the obtained Doppler velocimetric indexes, for the assessment of the feto-placental circulation, andprediction of fetal viability indexes, fetal centralization and probable date of delivery.Materials, Methods & Results: Thirty healthy bitches were examined in the final third of gestation (40-60 days). Thesewere evaluated by Doppler ultrasonography at 2 times (T): T1: between 40-50 days; T2: between 51-60 of gestation.At each time point, the peak systolic velocities (PSV) and end-diastolic velocities (EDV) used to obtain the pulsatility(IP) and resistivity (IR) indexes of the umbilical, uteroplacental, middle cerebral and internal carotid arteries of fetuseswere evaluated. Also, the systole/diastole (S/D) ratio of these vessels was evaluated. The data obtained were subjected toanalysis of variance and Tukey test, using a P value equal to 5%. A significant difference was observed between velocitiesand Doppler velocimetric indexes between the 2 phases of the gestational final third in all studied vessels. There was anincrease in the values of PSV and EDV and a decrease in the indexes, as the probable date of delivery approached. Theanalysis of the umbilical cord IR showed an increase from P1 to P2 (P < 0.05), while the IP decreased at the same time.For all studied variables there was a statistically significant difference (P < 0.05). In the uteroplacental...(AU)

Presumed normal hemodynamic values of the arteries in the final third period of gestation in bitches

Background: Doppler ultrasonography enables the investigation of vascular blood flow indexes in gestational assessment,being able to detect vascular resistances that can affect fetal and maternal circulation, such as cases of placental insufficiency, associated with fetal cerebral oxygenation deficit and fetal distress. The study aims to assume hemodynamicallynormal values in the final third of gestation in bitches, of the umbilical, uteroplacental, middle cerebral and internal carotidarteries, correlating the obtained Doppler velocimetric indexes, for the assessment of the feto-placental circulation, andprediction of fetal viability indexes, fetal centralization and probable date of delivery.Materials, Methods & Results: Thirty healthy bitches were examined in the final third of gestation (40-60 days). Thesewere evaluated by Doppler ultrasonography at 2 times (T): T1: between 40-50 days; T2: between 51-60 of gestation.At each time point, the peak systolic velocities (PSV) and end-diastolic velocities (EDV) used to obtain the pulsatility(IP) and resistivity (IR) indexes of the umbilical, uteroplacental, middle cerebral and internal carotid arteries of fetuseswere evaluated. Also, the systole/diastole (S/D) ratio of these vessels was evaluated. The data obtained were subjected toanalysis of variance and Tukey test, using a P value equal to 5%. A significant difference was observed between velocitiesand Doppler velocimetric indexes between the 2 phases of the gestational final third in all studied vessels. There was anincrease in the values of PSV and EDV and a decrease in the indexes, as the probable date of delivery approached. Theanalysis of the umbilical cord IR showed an increase from P1 to P2 (P < 0.05), while the IP decreased at the same time.For all studied variables there was a statistically significant difference (P < 0.05). In the uteroplacental...

Fetal distress during the last third of pregnancy in bitches - evaluation by Doppler ultrasound imaging

Background: Diagnostic ultrasound has revolutionized obstetric practice. Doppler techniques provided in vivo studies of the fetus-placental and uterus-placental circulations, in an increasingly precise manner. The assessment of fetal well-being is essential in obstetric practice, however, in veterinary medicine, there is a deficit of ultrasound parameters related to fetal distress. The main of this research was to determine the hemodynamic characteristics and behavior, through Doppler ultrasonography, of maternal-fetal vessels during the final third of gestation in bitches with fetuses under stress, as well as correlating them with each other and with fetal distress. Materials, Methods & Results: An observational, prospective study was carried out, in which 30 healthy bitches were examined, during the last third of pregnancy, with fetuses under fetal distress. Fetuses were evaluated in 2 stages: (1st): 50-54 days and (2nd): 55-60 days of gestation. All fetuses were calmly assessed, one by one, and fetal heart rate (FHR) was measured 5 times, for at least 3 min, to identify and confirm fetal distress. At least 3 fetuses were evaluated in each bitch and each measurement was performed in triplicate, setting a hemodynamic mean for each value evaluated. The flow pattern in the middle cerebral artery (MCA), internal carotid artery (ICA) and umbilical artery (UA) was evaluated. The analyzed vessel was initially visualized in B mode, followed by evaluation by color and spectral Doppler. The variables observed were: peak systolic velocity (PSV), end diastolic velocity (EDV) and the resistivity (RI) and pulsatility (PI) index, as well as the systole/diastole ratio (S/D). The analysis of RI and PI of the umbilical artery showed a statistically significant difference between the mean values found for the times studied, increasing from time 1 to time 2. For middle cerebral and internal carotid arteries, PI, RI and the relationship systole/diastole (S/D), showed a statistically significant difference between the mean values found for the times studied, decreasing from time 1 to time 2. Discussion: Fetal heart rate (HR) findings are considered normal above 200 beats per minute (bpm), only if preceded by acceleration and deceleration. This fact confirms the presence of fetal stress, by this parameter, for the fetuses in the present study. Corroborating the picture of fetal distress, another study concluded that HR tends to increase up to 20 days before delivery, a fact that did not occur in the study in question, where animals in the same gestational period were evaluated. Recent research has concluded that an elevated umbilical artery PI at 28 weeks of gestation, in the absence of fetal growth restriction or prematurity, is associated with some adverse cognitive findings in 12-year-olds children. In the present study, a progressive increase in this index was observed throughout the final third of pregnancy. Although the pups were not monitored after birth, this data serves as a warning for veterinarians, and can be useful in the assessment and diagnosis of possible postnatal nervous alterations. Like what was found in the present study, a study reported that from the 4th week to birth, the PSV of the umbilical artery (UA) increased almost linearly, with high significance. For the middle cerebral arteries, the PI showed a statistically significant difference between the mean values found for the times studied, however, decreasing throughout the final third of pregnancy.

Systematization, distribution, and territories of the caudal cerebral artery on the surface of the brain in nutria (Myocastor coypus) / Sistematização, distribuição e territórios da artéria cerebral caudal na superfície do cérebro em Nutria (Myocastor coypus)

The nutria (Myocastor coypus) is a medium-sized, semi-aquatic rodent valued by the skin and meat industry. This study aimed to describe and systematize the caudal cerebral artery on the brain surface in nutria, establishing a standard model and its main variations in this species. The thirty animals used were euthanized according to animal welfare rules. The vessels were filled with latex stained with red pigment and the samples were fixed in formaldehyde. In nutria, the brain was vascularized by the vertebral basilar system. The terminal branches of the basilar artery originated the rostral cerebellar, caudal cerebral, rostral choroidal and middle cerebral arteries, and its terminal branch, the rostral cerebral artery. The terminal branch of the basilar artery projected the caudal cerebral artery, which is usually a single medium-caliber vessel, into the transverse fissure of the brain. The caudal cerebral artery was presented as a single (66.7% of the cases to the right and 76.7% to the left) and double vessel (33.3% of the cases to the right and 23.3% to the left). It originated the rostral mesencephalic artery, the proximal component, and the caudal inter-hemispheric artery. The terminal branches of the rostral and caudal tectal mesencephalic arteries formed a typical anastomotic network. The caudal inter-hemispheric artery emitted central branches, the caudal choroidal artery, hemispherical occipital arteries, rostral tectal mesencephalic branches and distal components, and anastomosed "in osculum" with the terminal branches of the rostral inter-hemispheric artery. The caudal choroidal artery anastomosed with the rostral choroidal artery, where it branched out on the thalamic mass, vascularizing all diencephalic structures and the hippocampus. The caudal cerebral artery and its terminal branches anastomosed with the terminal branches of the rostral and middle cerebral arteries in a restricted region of the caudal pole of the cerebral hemisphere. The vascularization area of the caudal cerebral artery and its central branches in the paleopallial of the piriform lobe is extremely restricted, caudomedially.(AU)

A nutria (Myocastor coypus) é um roedor semi-aquático de tamanho mediano, apreciado na indústria de peles e carne. Este trabalho tem por objetivo descrever e sistematizar a artéria cerebral caudal na superfície do cérebro em nutria, estabelecendo um modelo padrão e suas principais variações e territórios nesta espécie. Os trinta animais utilizados foram eutanasiados segundo as regras de bem-estar animal, os vasos foram preenchidos com látex, corado em vermelho e as peças foram fixadas em formoldeído. O cérebro foi vascularizado exclusivamente pelo sistema vértebro-basilar. Os ramos terminais da artéria basilar originaram as artérias cerebelar rostral, cerebral caudal, corióidea rostral, cerebral média e seu ramo terminal, a artéria cerebral rostral. O ramo terminal da artéria basilar lançou a artéria cerebral caudal, um vaso normalmente único, de médio calibre, para o interior da fissura transversa do cérebro. A artéria cerebral caudal foi um vaso único em 66,7% à direita e em 76,7% à esquerda e mostrou-se dupla em 33,3% à direita e em 23,3% à esquerda. Ela lançou a artéria tectal mesencefálica rostral, componente proximal e a artéria inter-hemisférica caudal. Os ramos terminais das artérias tectais mesencefálicas, rostral e caudal, formavam uma rede anastomótica típica. A artéria inter-hemisférica caudal lançou ramos centrais, a artéria corióidea caudal, as artérias hemisféricas occipitais, os ramos tectais mesencefálicos rostrais, componentes distais e anastomosou-se "em ósculo" com o ramo terminal da artéria inter-hemisférica rostral. A artéria corióidea caudal anastomosava-se com a artéria corióidea rostral, onde ramificavam-se sobre a massa talâmica, vascularizando todas as estruturas do diencéfalo e hipocampo. A artéria cerebral caudal com seus ramos terminais apresenta anastomoses com os ramos terminais das artérias cerebrais rostral e média em uma região restrita do pólo caudal do hemisfério cerebral. A área de vascularização da artéria cerebral caudal com seus ramos centrais no páleo-palio do lobo piriforme é extremamente restrita, caudo-medialmente ao mesmo.(AU)

Systematization, distribution, and territories of the caudal cerebral artery on the surface of the brain in nutria (Myocastor coypus) / Sistematização, distribuição e territórios da artéria cerebral caudal na superfície do cérebro em Nutria (Myocastor coypus)

The nutria (Myocastor coypus) is a medium-sized, semi-aquatic rodent valued by the skin and meat industry. This study aimed to describe and systematize the caudal cerebral artery on the brain surface in nutria, establishing a standard model and its main variations in this species. The thirty animals used were euthanized according to animal welfare rules. The vessels were filled with latex stained with red pigment and the samples were fixed in formaldehyde. In nutria, the brain was vascularized by the vertebral basilar system. The terminal branches of the basilar artery originated the rostral cerebellar, caudal cerebral, rostral choroidal and middle cerebral arteries, and its terminal branch, the rostral cerebral artery. The terminal branch of the basilar artery projected the caudal cerebral artery, which is usually a single medium-caliber vessel, into the transverse fissure of the brain. The caudal cerebral artery was presented as a single (66.7% of the cases to the right and 76.7% to the left) and double vessel (33.3% of the cases to the right and 23.3% to the left). It originated the rostral mesencephalic artery, the proximal component, and the caudal inter-hemispheric artery. The terminal branches of the rostral and caudal tectal mesencephalic arteries formed a typical anastomotic network. The caudal inter-hemispheric artery emitted central branches, the caudal choroidal artery, hemispherical occipital arteries, rostral tectal mesencephalic branches and distal components, and anastomosed "in osculum" with the terminal branches of the rostral inter-hemispheric artery. The caudal choroidal artery anastomosed with the rostral choroidal artery, where it branched out on the thalamic mass, vascularizing all diencephalic structures and the hippocampus. The caudal cerebral artery and its terminal branches anastomosed with the terminal branches of the rostral and middle cerebral arteries in a restricted region of the caudal pole of the cerebral hemisphere. The vascularization area of the caudal cerebral artery and its central branches in the paleopallial of the piriform lobe is extremely restricted, caudomedially.(AU)

A nutria (Myocastor coypus) é um roedor semi-aquático de tamanho mediano, apreciado na indústria de peles e carne. Este trabalho tem por objetivo descrever e sistematizar a artéria cerebral caudal na superfície do cérebro em nutria, estabelecendo um modelo padrão e suas principais variações e territórios nesta espécie. Os trinta animais utilizados foram eutanasiados segundo as regras de bem-estar animal, os vasos foram preenchidos com látex, corado em vermelho e as peças foram fixadas em formoldeído. O cérebro foi vascularizado exclusivamente pelo sistema vértebro-basilar. Os ramos terminais da artéria basilar originaram as artérias cerebelar rostral, cerebral caudal, corióidea rostral, cerebral média e seu ramo terminal, a artéria cerebral rostral. O ramo terminal da artéria basilar lançou a artéria cerebral caudal, um vaso normalmente único, de médio calibre, para o interior da fissura transversa do cérebro. A artéria cerebral caudal foi um vaso único em 66,7% à direita e em 76,7% à esquerda e mostrou-se dupla em 33,3% à direita e em 23,3% à esquerda. Ela lançou a artéria tectal mesencefálica rostral, componente proximal e a artéria inter-hemisférica caudal. Os ramos terminais das artérias tectais mesencefálicas, rostral e caudal, formavam uma rede anastomótica típica. A artéria inter-hemisférica caudal lançou ramos centrais, a artéria corióidea caudal, as artérias hemisféricas occipitais, os ramos tectais mesencefálicos rostrais, componentes distais e anastomosou-se "em ósculo" com o ramo terminal da artéria inter-hemisférica rostral. A artéria corióidea caudal anastomosava-se com a artéria corióidea rostral, onde ramificavam-se sobre a massa talâmica, vascularizando todas as estruturas do diencéfalo e hipocampo. A artéria cerebral caudal com seus ramos terminais apresenta anastomoses com os ramos terminais das artérias cerebrais rostral e média em uma região restrita do pólo caudal do hemisfério cerebral. A área de vascularização da artéria cerebral caudal com seus ramos centrais no páleo-palio do lobo piriforme é extremamente restrita, caudo-medialmente ao mesmo.(AU)

Sistematização e descrição da vascularização arterial da área páleo-palial na superfície do cérebro de chinchila (Chinchilla lanigera) / Systematization and description of arterial vascularization of the paleopallia area on the brain surface of chinchilla (Chinchilla lanigera)

Background: Chinchilla (Chinchilla lanigera) is a small rodent that in recent years has been increasingly used as a laboratory animal by different researchers. Brain irrigation is the object of study by several authors, being chinchilla classifiedas a vertebrobasillary animal, that is, it does not depend on the internal carotid artery to originate its cerebral arterialvascularization. Thus, the objective of this study was to systematize and describe the branches of the rostral, middle andcaudal cerebral arteries that vascularized the paleopallia area of the chinchilla.Materials, Methods & Results: Thirty Chinchilla lanigera brains were used in this study, 17 females and 13 adult malesfrom farms in the municipalities of Viamão and Santa Maria in the state of Rio Grande do Sul, Brazil. The animals wereheparinized, with 5000 IU / animal, and after 30 min were sacrificed with 8 mL / 2.5% sodium thiopental animal, bothintraperitoneally. The thoracic cavity was opened, the cardiac apex sectioned and the aortic arch was cannulated throughthe left ventricle. The arterial system was flushed with 0.9% cooled saline, 100mL / animal and then filled with 603 latexstained red with specific dye. The skin was recessed and a bone window opened in the cranial vault. Thus the pieces werefixed in 20% formaldehyde for seven days and after this period, the brain with a cervical spinal cord segment was removedand ventral schematic drawings of all preparations were prepared. The Veterinary Anatomical Nomina (2017) was usedto name the cerebral arteries and their branches and for the statistical analysis of the results, the percentage calculationwas applied. Brain irrigation in the chinchilla was supplied by the basilar artery, which was formed by anastomosis of theterminal branches of the right and left vertebral arteries, in the most caudal portion of the oblong medulla. The paleopalliaareas corresponded to the olfactory trine, lateral brain fossa, piriform lobe...

Sistematização e descrição da vascularização arterial da área páleo-palial na superfície do cérebro de chinchila (Chinchilla lanigera) / Systematization and description of arterial vascularization of the paleopallia area on the brain surface of chinchilla (Chinchilla lanigera)

Background: Chinchilla (Chinchilla lanigera) is a small rodent that in recent years has been increasingly used as a laboratory animal by different researchers. Brain irrigation is the object of study by several authors, being chinchilla classifiedas a vertebrobasillary animal, that is, it does not depend on the internal carotid artery to originate its cerebral arterialvascularization. Thus, the objective of this study was to systematize and describe the branches of the rostral, middle andcaudal cerebral arteries that vascularized the paleopallia area of the chinchilla.Materials, Methods & Results: Thirty Chinchilla lanigera brains were used in this study, 17 females and 13 adult malesfrom farms in the municipalities of Viamão and Santa Maria in the state of Rio Grande do Sul, Brazil. The animals wereheparinized, with 5000 IU / animal, and after 30 min were sacrificed with 8 mL / 2.5% sodium thiopental animal, bothintraperitoneally. The thoracic cavity was opened, the cardiac apex sectioned and the aortic arch was cannulated throughthe left ventricle. The arterial system was flushed with 0.9% cooled saline, 100mL / animal and then filled with 603 latexstained red with specific dye. The skin was recessed and a bone window opened in the cranial vault. Thus the pieces werefixed in 20% formaldehyde for seven days and after this period, the brain with a cervical spinal cord segment was removedand ventral schematic drawings of all preparations were prepared. The Veterinary Anatomical Nomina (2017) was usedto name the cerebral arteries and their branches and for the statistical analysis of the results, the percentage calculationwas applied. Brain irrigation in the chinchilla was supplied by the basilar artery, which was formed by anastomosis of theterminal branches of the right and left vertebral arteries, in the most caudal portion of the oblong medulla. The paleopalliaareas corresponded to the olfactory trine, lateral brain fossa, piriform lobe...(AU)

Anatomic study of the arterial vascularization of the brain base of paca (Cuniculus paca) / Estudo anatômico da vascularização arterial da base do encéfalo da paca (Cuniculus paca)

Paca (Cuniculus paca Linnaeus, 1766), rodent belong to the Cuniculidae family, has encouraged numerous scientific researches and for this reason could be an experimental model in both human and veterinary areas. And recently, the economic exploitation of the meat cuts, has being direct implication in its zootechnical importance. However, no anatomical descriptions regarding the vascularization of the base of the brain in this rodent has being found. Thus, the aim of the present study was to describe the arteries and the pattern of the vasculature and to compare it with the other species already established in the literature. For this, five pacas, donated by the Unesp Jaboticabal Wildlife Sector, were euthanized followed by the vascular arterial system was injected with red-stained-centrifuged latex by the common carotid artery. After craniectomy, the brains were removed and the arteries were identified and, in addition, compared with those described in other animal species. The presence of the right and left vertebral arteries, close to the medulla oblongata, was detected, originating the basilar artery, which divided into the terminal branches of the right and left basilar artery. Ventral to the optic tract there was the right internal carotid artery and the left, dividing the middle cerebral artery and left rostral and right; dorsal to the optic chiasm, the medial branch of the rostral cerebral arteries was identified. Based on the results, it is concluded that the vascularization of the paca brain base is supplied by the carotid and vertebrobasilar system.(AU)

A paca (Cuniculus paca Linnaeus 1766), roedor da família Cuniculidae, tem encorajado inúmeras pesquisas científicas, tornando-a modelo experimental tanto na área humana quanto na veterinária, além da recente exploração econômica de seus cortes cárneos, que favoreceu diretamente sua importância zootécnica. No entanto, não há até o momento, descrições anatômicas referentes à padronização da vascularização da base do encéfalo neste roedor. Assim, o objetivo do presente trabalho foi realizar tal delineamento arterial nessa região do sistema nervoso central e compará-lo com as demais espécies já estabelecidas na literatura. Para isso, foram eutanasiadas cinco pacas doadas pelo setor de Animais Silvestres da Unesp Jaboticabal, as quais foram submetidas posteriormente à injeção de látex centrifugado e corante líquido xadrez vermelho, pela artéria carótida comum. Após craniectomia e segregação do encéfalo de todos os cadáveres, realizou-se a identificação das artérias presentes na base deste órgão e, ademais, comparação destas com as descritas cientificamente em outras espécies animais. Detectou-se a presença das artérias vertebral direita e esquerda, próximas à medula oblonga, originando a artéria basilar, que se dividiu nos ramos terminais da artéria basilar direito e esquerdo. Ventral ao trato óptico verificou-se a artéria carótida interna direita e esquerda dividindo-se na artéria cerebral média e rostral direita e esquerda; ainda, dorsal ao quiasma óptico, identificou-se o ramo medial das artérias cerebrais rostrais. Com base nos resultados obtidos, conclui-se que a vascularização da base do encéfalo da paca é suprida pelo sistema carotídeo e vertebro-basilar.(AU)

Anatomic study of the arterial vascularization of the brain base of paca (Cuniculus paca) / Estudo anatômico da vascularização arterial da base do encéfalo da paca (Cuniculus paca)

Paca (Cuniculus paca Linnaeus, 1766), rodent belong to the Cuniculidae family, has encouraged numerous scientific researches and for this reason could be an experimental model in both human and veterinary areas. And recently, the economic exploitation of the meat cuts, has being direct implication in its zootechnical importance. However, no anatomical descriptions regarding the vascularization of the base of the brain in this rodent has being found. Thus, the aim of the present study was to describe the arteries and the pattern of the vasculature and to compare it with the other species already established in the literature. For this, five pacas, donated by the Unesp Jaboticabal Wildlife Sector, were euthanized followed by the vascular arterial system was injected with red-stained-centrifuged latex by the common carotid artery. After craniectomy, the brains were removed and the arteries were identified and, in addition, compared with those described in other animal species. The presence of the right and left vertebral arteries, close to the medulla oblongata, was detected, originating the basilar artery, which divided into the terminal branches of the right and left basilar artery. Ventral to the optic tract there was the right internal carotid artery and the left, dividing the middle cerebral artery and left rostral and right; dorsal to the optic chiasm, the medial branch of the rostral cerebral arteries was identified. Based on the results, it is concluded that the vascularization of the paca brain base is supplied by the carotid and vertebrobasilar system.(AU)

A paca (Cuniculus paca Linnaeus 1766), roedor da família Cuniculidae, tem encorajado inúmeras pesquisas científicas, tornando-a modelo experimental tanto na área humana quanto na veterinária, além da recente exploração econômica de seus cortes cárneos, que favoreceu diretamente sua importância zootécnica. No entanto, não há até o momento, descrições anatômicas referentes à padronização da vascularização da base do encéfalo neste roedor. Assim, o objetivo do presente trabalho foi realizar tal delineamento arterial nessa região do sistema nervoso central e compará-lo com as demais espécies já estabelecidas na literatura. Para isso, foram eutanasiadas cinco pacas doadas pelo setor de Animais Silvestres da Unesp Jaboticabal, as quais foram submetidas posteriormente à injeção de látex centrifugado e corante líquido xadrez vermelho, pela artéria carótida comum. Após craniectomia e segregação do encéfalo de todos os cadáveres, realizou-se a identificação das artérias presentes na base deste órgão e, ademais, comparação destas com as descritas cientificamente em outras espécies animais. Detectou-se a presença das artérias vertebral direita e esquerda, próximas à medula oblonga, originando a artéria basilar, que se dividiu nos ramos terminais da artéria basilar direito e esquerdo. Ventral ao trato óptico verificou-se a artéria carótida interna direita e esquerda dividindo-se na artéria cerebral média e rostral direita e esquerda; ainda, dorsal ao quiasma óptico, identificou-se o ramo medial das artérias cerebrais rostrais. Com base nos resultados obtidos, conclui-se que a vascularização da base do encéfalo da paca é suprida pelo sistema carotídeo e vertebro-basilar.(AU)

Vascularization of the Alouatta belzebul brain base / Vascularização da base do encéfalo de Alouatta belzebul

We studied the arterial circle in the brain of five specimens of the Alouatta belzebul primate. The material had the arterial system perfused (water at 40°C), injected with stained latex (Neoprene 650), fixed in aqueous formaldehyde solution (10%) and dissected for vessel verification. The arterial circle of this primate is composed of two vascular systems: the vertebra-basilar and the carotid ones, which anastomose to close the arterial circuit. In the caudal portion of the arterial circle, there are the vertebral arteries and their branches: the rostral spinal artery and the caudal inferior cerebellar artery. The anastomosis of the vertebral arteries gives rise to the basilar artery. It presented an anatomical variation at the beginning of its path, forming a double basilar artery, called arterial island. In its course, it emitted branches giving rise to the rostral inferior cerebellar artery, the pontine arteries, the rostral cerebellar arteries, the satellite rostral cerebellar arteries and its terminal branch, the caudal cerebral artery, which presented itself in two segments: the pre-communicating one and post-communicating, joining the internal carotid artery and originating the caudal communicating artery. This group of arteries and anastomoses enclose the caudal portion of the arterial circle. From the right and left internal carotid arteries begins the rostral portion of the arterial circle, which consists of the right and left rostral cerebral arteries and the right and left middle cerebral arteries. The rostral cerebral arteries anastomose into a single trunk, giving rise to the interhemispheric artery, and in A. belzebul and Sapajus libidinosus, the rostral communicating artery is absent. The interhemispheric artery goes to the midbrain region and the corpus callosum knee divides into pericalous artery and callosarginal artery, which will supply the pre and post-central regions of the cerebral hemispheres of this species, as well as other non-human and human primates. It is noted that in the first part of the left rostral cerebral artery, there is a direct inosculation between the recurrent branch of the rostral cerebral artery and left middle cerebral artery to supply the entorhinal region. This fact also occurs in Pongo spp. The middle cerebral artery travels along the lateral sulcus where it emits several superficial branches to irrigate the superior and inferior lateral cortical regions of the frontal, parietal and temporal lobes. It is not part of the arterial circle but is the terminal branch of the internal carotid artery. A. belzebul can be considered to depend on two sources of supply to the brain: the vertebra-basilar and carotid systems, contributing to the intervention of veterinarians during clinical and surgical procedures in other primates, as well as the preservation of wild animals.(AU)

Estudamos o círculo arterial no encéfalo de cinco espécimes do primata Alouatta belzebul. O material teve o sistema arterial perfundido (água a 40°C), injetado com látex corado (Neoprene 650), fixado em solução aquosa de formaldeído (10%) e dissecado para verificação dos vasos. O círculo arterial deste primata é composto por dois sistemas vasculares: vértebro-basilar e o sistema carotídeo, que se anastomosam para fechar o circuito arterial. Na porção caudal do círculo arterial encontra-se as artérias vertebrais e seus ramos: artéria espinal rostral e a cerebelar inferior caudal. A anastomose das artérias vertebrais dá origem a artéria basilar. Esta apresentou uma variação anatômica no início do seu trajeto, formando uma dupla artéria basilar, denominada ilha arterial. Em seu trajeto emitiu ramos dando origem a artéria cerebelar inferior rostral, as artérias pontinas, as artérias cerebelares rostrais, as artérias cerebelares rostrais satélites e o seu ramo terminal, a artéria cerebral caudal, que apresentou-se em dois segmentos: o pré-comunicante e pós-comunicante, unindo-se a artéria carótida interna e originando a artéria comunicante caudal. Este grupo de artérias e anastomoses encerram a porção caudal do círculo arterial. Das artérias carótidas internas direita e esquerda, inicia-se a porção rostral do círculo arterial, ao qual é constituído pelas artérias cerebrais rostrais direita e esquerda e as artérias cerebrais médias direita e esquerda. As artérias cerebrais rostrais se anastomosam em um tronco único dando origem a artéria inter-hemisférica e em A. belzebul e Sapajus libidinosus, a artéria comunicante rostral se encontra ausente. A artéria inter-hemisférica segue para região média do encéfalo e no joelho do corpo caloso se divide em artéria pericalosa e artéria calosomarginal, que vão suprir as regiões pré e pós-central dos hemisférios cerebrais desta espécie, assim como outros primatas não humanos e humano. Nota-se que na primeira parte da artéria cerebral rostral esquerda, ocorre uma inosculação direta entre o ramo recorrente da artéria cerebral rostral e artéria cerebral média esquerda para suprir a região entorrinal, esse fato também ocorre em Pongo spp. A artéria cerebral média segue seu trajeto pelo sulco lateral onde emite vários ramos superficiais para irrigar as regiões corticais supero e ínfero lateral do lobo frontal, parietal e temporal, esta não faz parte do círculo arterial mas é o ramo terminal da artéria carótida interna. Pode-se considerar que A. belzebul depende de duas fontes de suprimento para o encéfalo: os sistemas vértebro-basilar e carotídeo, contribuindo na intervenção de médicos veterinários durante os procedimentos clínicos e cirúrgicos em outros primatas, assim como na preservação de animais silvestres.(AU)

Vascularization of the Alouatta belzebul brain base / Vascularização da base do encéfalo de Alouatta belzebul

We studied the arterial circle in the brain of five specimens of the Alouatta belzebul primate. The material had the arterial system perfused (water at 40°C), injected with stained latex (Neoprene 650), fixed in aqueous formaldehyde solution (10%) and dissected for vessel verification. The arterial circle of this primate is composed of two vascular systems: the vertebra-basilar and the carotid ones, which anastomose to close the arterial circuit. In the caudal portion of the arterial circle, there are the vertebral arteries and their branches: the rostral spinal artery and the caudal inferior cerebellar artery. The anastomosis of the vertebral arteries gives rise to the basilar artery. It presented an anatomical variation at the beginning of its path, forming a double basilar artery, called arterial island. In its course, it emitted branches giving rise to the rostral inferior cerebellar artery, the pontine arteries, the rostral cerebellar arteries, the satellite rostral cerebellar arteries and its terminal branch, the caudal cerebral artery, which presented itself in two segments: the pre-communicating one and post-communicating, joining the internal carotid artery and originating the caudal communicating artery. This group of arteries and anastomoses enclose the caudal portion of the arterial circle. From the right and left internal carotid arteries begins the rostral portion of the arterial circle, which consists of the right and left rostral cerebral arteries and the right and left middle cerebral arteries. The rostral cerebral arteries anastomose into a single trunk, giving rise to the interhemispheric artery, and in A. belzebul and Sapajus libidinosus, the rostral communicating artery is absent...(AU)

Estudamos o círculo arterial no encéfalo de cinco espécimes do primata Alouatta belzebul. O material teve o sistema arterial perfundido (água a 40°C), injetado com látex corado (Neoprene 650), fixado em solução aquosa de formaldeído (10%) e dissecado para verificação dos vasos. O círculo arterial deste primata é composto por dois sistemas vasculares: vértebro-basilar e o sistema carotídeo, que se anastomosam para fechar o circuito arterial. Na porção caudal do círculo arterial encontra-se as artérias vertebrais e seus ramos: artéria espinal rostral e a cerebelar inferior caudal. A anastomose das artérias vertebrais dá origem a artéria basilar. Esta apresentou uma variação anatômica no início do seu trajeto, formando uma dupla artéria basilar, denominada ilha arterial. Em seu trajeto emitiu ramos dando origem a artéria cerebelar inferior rostral, as artérias pontinas, as artérias cerebelares rostrais, as artérias cerebelares rostrais satélites e o seu ramo terminal, a artéria cerebral caudal, que apresentou-se em dois segmentos: o pré-comunicante e pós-comunicante, unindo-se a artéria carótida interna e originando a artéria comunicante caudal. Este grupo de artérias e anastomoses encerram a porção caudal do círculo arterial. Das artérias carótidas internas direita e esquerda, inicia-se a porção rostral do círculo arterial, ao qual é constituído pelas artérias cerebrais rostrais direita e esquerda e as artérias cerebrais médias direita e esquerda. As artérias cerebrais rostrais se anastomosam em um tronco único dando origem a artéria inter-hemisférica e em A. belzebul e Sapajus libidinosus, a artéria comunicante rostral se encontra ausente. A artéria inter-hemisférica segue para região média do encéfalo e no joelho do corpo caloso se divide em artéria pericalosa e artéria calosomarginal, que vão suprir as regiões pré e pós-central dos hemisférios cerebrais desta espécie, assim como outros primatas não humanos e humano...(AU)

Laminotomia dorsal do áxis para excisão de meningioma em cão / Axis dorsal laminotomy for excision of a meningioma in a dog

Background: Surgical access to the spinal cord at the level of C2 vertebra presents technical limitations, due to anatomical particularities in this region. The ventral slot technique does not allow space for the removal of dorsolateral masses. The axis hemilaminectomy technique provides limited access to the dorsal aspect of spinal cord and there is a risk of damaging the vertebral arteries. The axis dorsal laminotomy technique allows good access to spinal cord and preserves the atlantoaxial and nuchal ligaments, however few papers describe this technique. The objective of this paper is to report the axis dorsal laminotomy performed in a dog with a meningioma at this level. Case: An 11-year-old male, Maltese dog, was presented with a 15-day history of progressive weakness, intense cervical pain and difficulty in locomotion of the four limbs. He was being treated with painkillers without improvement. On clinical examination, the physiological parameters were normal. Neurological examination showed tetraparesis with the syndrome localized in the cranial cervical region. The main differential diagnoses were intervertebral disc disease, neoplasia, inflammatory or infectious disease. Computed tomography was performed and the evaluation of images allowed the visualization of an intradural-extramedullary neoplastic process, promoting important spinal compression, with approximate dimensions of the lesion 0.70 cm high x 0.67 cm wide x 0.78 cm long, with apparent involvement of the meninges, with a more lateralized location on the left, with meningioma being the main differential diagnosis. Thus, exploratory surgery, through the technique of dorsal laminotomy of the axis was performed. After the removal of the mass, the spinous process was repositioned in its anatomical location and fixed with 0.6 mm steel cerclage wire that was passed through the holes made in the dorsal lamina of the...

Laminotomia dorsal do áxis para excisão de meningioma em cão / Axis dorsal laminotomy for excision of a meningioma in a dog

Background: Surgical access to the spinal cord at the level of C2 vertebra presents technical limitations, due to anatomical particularities in this region. The ventral slot technique does not allow space for the removal of dorsolateral masses. The axis hemilaminectomy technique provides limited access to the dorsal aspect of spinal cord and there is a risk of damaging the vertebral arteries. The axis dorsal laminotomy technique allows good access to spinal cord and preserves the atlantoaxial and nuchal ligaments, however few papers describe this technique. The objective of this paper is to report the axis dorsal laminotomy performed in a dog with a meningioma at this level. Case: An 11-year-old male, Maltese dog, was presented with a 15-day history of progressive weakness, intense cervical pain and difficulty in locomotion of the four limbs. He was being treated with painkillers without improvement. On clinical examination, the physiological parameters were normal. Neurological examination showed tetraparesis with the syndrome localized in the cranial cervical region. The main differential diagnoses were intervertebral disc disease, neoplasia, inflammatory or infectious disease. Computed tomography was performed and the evaluation of images allowed the visualization of an intradural-extramedullary neoplastic process, promoting important spinal compression, with approximate dimensions of the lesion 0.70 cm high x 0.67 cm wide x 0.78 cm long, with apparent involvement of the meninges, with a more lateralized location on the left, with meningioma being the main differential diagnosis. Thus, exploratory surgery, through the technique of dorsal laminotomy of the axis was performed. After the removal of the mass, the spinous process was repositioned in its anatomical location and fixed with 0.6 mm steel cerclage wire that was passed through the holes made in the dorsal lamina of the...(AU)

Acute effects of whole-body vibration on dopplerfluxometry of the common carotid artery parameters among adult and elderly non-athletes healthy dogs

Background: Whole-Body Vibration (WBV) is an oscillatory mechanical stimulus spreading throughout the body and considered a type of physical exercise because of the activation of the cardiovascular, musculoskeletal, and neuroendocrine systems. It is a physical exercise modality since it promotes cardiovascular resistance, increase in muscular strength and neurosensitivity, and motor coordination improvement. For use of WBV as an exercise modality for dogs, it is necessary to evaluate the Dopplerfluxometry parameters of the common carotid artery in healthy dogs in order to perform a safe protocol without inducing any cerebral alteration. This study aimed to evaluate the acute effects of WBV on systolic peak velocity (SPV), resistivity (RI), and pulsatility index (PI) of the both common carotid artery among adults and elderly non-athletes healthy dog. Materials, Methods & Results: Fourteen clinically healthy, neutered crossbreed male dogs, non-athlete were divided into two groups of seven dogs, according to the age group: Group 1 (G1)- Adult dogs: age between 12 and 84 months; Group 2 (G2)- Elderly dogs: aged over 84 months. All dogs were submitted to sessions of WBV using the protocol of 30 Hz for 5 min, followed by an increase to 50 Hz for 5 more min and ending with 5 min at 30 Hz, without rest between the variation of the vibration frequency. The systolic peak velocity (SPV), resistivity (RI), and pulsatility index (PI) of the common carotid artery were assessed in two time-points: 5 min before the WBV sessions (5PRE) and 1 min after the WBV (1POS). No significant variations in the SPS, RI, and PI of both common carotid artery of the G1 and G2 were identified. The anatomic reference for the left and right common carotid artery was the right and left extern jugulars veins, which were...

Sistematização e descrição da vascularização arterial do páleo-palio na superfície do cérebro de javali (Sus scrofa scrofa) / Systematization and description of the arterial blood supply of the paleopallia areas in the brain surface of the wild boar (Sus scrofa scrofa)

Background: The study was performed on wild boar (Sus scrofa scrofa) wich is a wild ancestor of the domestic pig and is not partof Brazilian fauna. The arterial blood supply of the encephalus has been studied by some researchers, who have systematized thecerebral blood supply from the rostral and caudal epidural rete mirabile and its sources in wild boar until the blood supply of the baseof the brain. The objective was to improve the understanding of the arterial blood supply of the brain, particularly the paleopallium,of the wild boar and to provide a reference for comparative anatomy studies.Materials, Methods & Results: A total of 30 brains were obtained from an officially authorised slaughterhouse and approved byBrazilian Institute of Environment and Natural Renowable Resources. The animals were desensitized, followed by bleending of thejugular veins and common carotid arteries near the entrance of the thorax, according to the slaughter procedure. Finally, the animalswere decapitated at the level of axis vertebra. The cerebral arterial system of each animal was rinsed (cooled saline containing 2500IU of heparin) and drained by the jugular veins, and vessels were filled with latex 603 stained with specific red dye. The heads weresubmerged for one hour in running water immersed in 20% formaldehyde for fixation; the brains were removed along with a cervicalsegment of the spinal cord. The duramater was removed, and the arteries were dissected. Schematic drawings of the ventral view ofthe all preparations were made using magnifying glasses and photographic records. The Nomina Anatomica Veterinaria was usedto named the cerebral arteries and their branches, and calculation of pecentages was applied in the statistical analysis. The cerebralcarotid artery originating from the rostral epidural rete mirabile emitted a rostral branch and a caudal branch on the side of the hypophysis gland...

Sistematização e descrição da vascularização arterial do páleo-palio na superfície do cérebro de javali (Sus scrofa scrofa) / Systematization and description of the arterial blood supply of the paleopallia areas in the brain surface of the wild boar (Sus scrofa scrofa)

Background: The study was performed on wild boar (Sus scrofa scrofa) wich is a wild ancestor of the domestic pig and is not partof Brazilian fauna. The arterial blood supply of the encephalus has been studied by some researchers, who have systematized thecerebral blood supply from the rostral and caudal epidural rete mirabile and its sources in wild boar until the blood supply of the baseof the brain. The objective was to improve the understanding of the arterial blood supply of the brain, particularly the paleopallium,of the wild boar and to provide a reference for comparative anatomy studies.Materials, Methods & Results: A total of 30 brains were obtained from an officially authorised slaughterhouse and approved byBrazilian Institute of Environment and Natural Renowable Resources. The animals were desensitized, followed by bleending of thejugular veins and common carotid arteries near the entrance of the thorax, according to the slaughter procedure. Finally, the animalswere decapitated at the level of axis vertebra. The cerebral arterial system of each animal was rinsed (cooled saline containing 2500IU of heparin) and drained by the jugular veins, and vessels were filled with latex 603 stained with specific red dye. The heads weresubmerged for one hour in running water immersed in 20% formaldehyde for fixation; the brains were removed along with a cervicalsegment of the spinal cord. The duramater was removed, and the arteries were dissected. Schematic drawings of the ventral view ofthe all preparations were made using magnifying glasses and photographic records. The Nomina Anatomica Veterinaria was usedto named the cerebral arteries and their branches, and calculation of pecentages was applied in the statistical analysis. The cerebralcarotid artery originating from the rostral epidural rete mirabile emitted a rostral branch and a caudal branch on the side of the hypophysis gland...(AU)

Exposição e ruptura da artéria carótida comum em cão / Exposure and rupture of the commom carotid artery in dog

O sistema cardiovascular tem a função de transportar substâncias essenciais à vida. Os vasos sanguíneos conduzem o conteúdo sanguíneo, tanto para a chegada de sangue arterial aos órgãos quanto para saída de sangue venoso. As artérias carótidas comum são originárias do tronco braquiocefálico, sendo o principal vaso responsável pelo aporte sanguíneo dos órgãos da cabeça. Qualquer alteração que prejudique a circulação cerebral pode gerar graves consequências fisiológicas ao animal. A ruptura da artéria carótida pode ser reconhecida como a mais temida das ocorrências na área cirúrgica de cabeça e pescoço com a perda de sangue excessiva advinda da ruptura de um vaso de calibre e pressão consideráveis, se não for atendido emergencialmente, o animal poderá entrar em um quadro de choque hipovolêmico, agravando o quadro do paciente. Por ser uma problemática não rotineira na clínica cirúrgica de pequenos animais, há poucos registros de casos semelhantes. No caso relatado, o animal apresentava lesão na região cervical, com exposição da veia jugular e ruptura da artéria carótida comum, com presença de hemorragia extrema. O procedimento cirúrgico transcorreu dentro dos parâmetros normais e sem imprevistos. Ao longo do acompanhamento clínico, o animal apresentou um póscirúrgico estável, sem sequelas neurológicas, seguindo os cuidados com relação aos curativos diários da ferida operatória, continuação do protocolo iniciado no pré-cirúrgico e medicações prescritas para recuperação do volume perdido de hemácias, apresentando uma recuperação positiva.

The cardiovascular system has the function of transporting essential substances to life. Blood vessels carry the blood content, both for the arrival of arterial blood to the organs and for venous blood output. The common carotid arteries originate from the brachiocephalic trunk, being the main vessel responsible for the blood supply of the head organs. Any alteration that impairs the cerebral circulation can have serious physiological consequences to the animal. Carotid artery rupture can be recognized as the most dreaded occurrence in the head and neck surgical area, with excessive blood loss from a ruptured vessel of considerable caliber and pressure. If left unattended, the animal may enter in a hypovolemic shock, aggravating the patient's condition. As it is a non-routine problem in the small animal surgical clinic, there are few reports of similar cases. In the reported case, the animal had cervical lesion, with exposure of the jugular vein and rupture of the common carotid artery, with the presence of extreme hemorrhage. The surgical procedurewas performed within normal parameters and without unforeseen events. During the clinical follow-up, the animal presented a stable postoperative period, without neurological sequelae, following the care regarding the daily wound dressing, continuation of the protocol initiated before the surgery and prescribed medications to recover the lost volume of red blood cells, showing a positive recovery.

Exposição e ruptura da artéria carótida comum em cão / Exposure and rupture of the commom carotid artery in dog

O sistema cardiovascular tem a função de transportar substâncias essenciais à vida. Os vasos sanguíneos conduzem o conteúdo sanguíneo, tanto para a chegada de sangue arterial aos órgãos quanto para saída de sangue venoso. As artérias carótidas comum são originárias do tronco braquiocefálico, sendo o principal vaso responsável pelo aporte sanguíneo dos órgãos da cabeça. Qualquer alteração que prejudique a circulação cerebral pode gerar graves consequências fisiológicas ao animal. A ruptura da artéria carótida pode ser reconhecida como a mais temida das ocorrências na área cirúrgica de cabeça e pescoço, com a perda de sangue excessiva advinda da ruptura de um vaso de calibre e pressão consideráveis, se não for atendido emergencialmente, o animal poderá entrar em um quadro de choque hipovolêmico, agravando o quadro do paciente. Por ser uma problemática não rotineira na clínica cirúrgica de pequenos animais, há poucos registros de casos semelhantes. No caso relatado, o animal apresentava lesão na região cervical, com exposição da veia jugular e ruptura da artéria carótida comum, com presença de hemorragia extrema. O procedimento cirúrgico transcorreu dentro dos parâmetros normais e sem imprevistos. Ao longo do acompanhamento clínico, o animal apresentou um pós cirúrgico estável, sem sequelas neurológicas, seguindo os cuidados com relação aos curativos diários da ferida operatória, continuação do protocolo iniciado no pré-cirúrgico e medicações prescritas para recuperação do volume perdido de hemácias, apresentando uma recuperação positiva.(AU)

The cardiovascular system has the function of transporting essential substances to life. Blood vessels carry the blood content, both for the arrival of arterial blood to the organs and for venous blood output. The common carotid arteries originate from the brachiocephalic trunk, being the main vessel responsible for the blood supply of the head organs. Any alteration that impairs the cerebral circulation can have serious physiological consequences to the animal. Carotid artery rupture can be recognized as the most dreaded occurrence in the head and neck surgical area, with excessive blood loss from a ruptured vessel of considerable caliber and pressure. If left unattended, the animal may enter in a hypovolemic shock, aggravating the patient's condition. As it is a non-routine problem in the small animal surgical clinic, there are few reports of similar cases. In the reported case, the animal had cervical lesion, with exposure of the jugular vein and rupture of the common carotid artery, with the presence of extreme hemorrhage. The surgical procedure was performed within normal parameters and without unforeseen events. During the clinical follow-up, the animal presented a stable postoperative period, without neurological sequelae, following the care regarding the daily wound dressing, continuation of the protocol initiated before the surgery and prescribed medications to recover the lost volume of red blood cells, showing a positive recovery.(AU)

Anatomia macroscópica e vascularização do encéfalo de emas (Rhea americana americana) / Macroscopic anatomy and brain vascularization in the greater rhea (Rhea americana americana)

Background: The Rhea americana americana is a wild bird belonging to the group of Ratites, and is important from the scientific point of view given their adaptability to captivity. Considering that information about its morphology is important for the viability of domesticating the species, the aim of this study was to macroscopically identify the brain regions, as well as the cerebral arteries and the cerebral arterial circuit in order to establish the cerebral vascular pattern and systematization.Materials, Methods & Results: Twenty one brains from young and adult Greater Rheas of both sexes were used from animals that had died due to natural causes and were then kept in a freezer. The specimens were thawed and incised in the cervical region to allow exposure of the left common carotid artery, which was cannulated. The vascular system was rinsed with 0.9% saline solution, then perfused with latex Neoprene 650 stained with red pigment. The animals were subsequently fixed in 3.7% aqueous formaldehyde solution for 72 h, and then they were dissected by removing the bones from the skull cap. The brains were analyzed, and the structures were identified, photographed, schematized and denominated. Morphometric measurements were performed on the basilar and cerebellar ventral caudal arteries, recording the values of length and width in millimeters with the aid of a digital caliper. The brain was divided into: telencephalon, diencephalon, brainstem and cerebellum; while externally, the observed structures are: olfactory bulbs, optical lobes, optic nerves, optic chiasm, pituitary and pineal glands. Vascularization was performed by the following arteries: ventral spinal artery, basilar artery, ventricular cerebellar arteries, medium ventricular cerebellar arteries, caudal branches of the carotid arteries of the brain, ventral mesencephalic artery, cerebral caudal arteries, rostral branches of the carotid arteries of the brain, middle cerebral arteries,[...]

Anatomia macroscópica e vascularização do encéfalo de emas (Rhea americana americana) / Macroscopic anatomy and brain vascularization in the greater rhea (Rhea americana americana)

Background: The Rhea americana americana is a wild bird belonging to the group of Ratites, and is important from the scientific point of view given their adaptability to captivity. Considering that information about its morphology is important for the viability of domesticating the species, the aim of this study was to macroscopically identify the brain regions, as well as the cerebral arteries and the cerebral arterial circuit in order to establish the cerebral vascular pattern and systematization.Materials, Methods & Results: Twenty one brains from young and adult Greater Rheas of both sexes were used from animals that had died due to natural causes and were then kept in a freezer. The specimens were thawed and incised in the cervical region to allow exposure of the left common carotid artery, which was cannulated. The vascular system was rinsed with 0.9% saline solution, then perfused with latex Neoprene 650 stained with red pigment. The animals were subsequently fixed in 3.7% aqueous formaldehyde solution for 72 h, and then they were dissected by removing the bones from the skull cap. The brains were analyzed, and the structures were identified, photographed, schematized and denominated. Morphometric measurements were performed on the basilar and cerebellar ventral caudal arteries, recording the values of length and width in millimeters with the aid of a digital caliper. The brain was divided into: telencephalon, diencephalon, brainstem and cerebellum; while externally, the observed structures are: olfactory bulbs, optical lobes, optic nerves, optic chiasm, pituitary and pineal glands. Vascularization was performed by the following arteries: ventral spinal artery, basilar artery, ventricular cerebellar arteries, medium ventricular cerebellar arteries, caudal branches of the carotid arteries of the brain, ventral mesencephalic artery, cerebral caudal arteries, rostral branches of the carotid arteries of the brain, middle cerebral arteries,[...](AU)