ABSTRACT
The perivascular space (PVS) surrounds cerebral blood vessels and plays an important role in clearing waste products from the brain. Their anatomy and function have been described for arteries, but PVS around veins remain poorly characterized. Using in vivo 2-photon imaging in mice, we determined the size of the PVS around arteries and veins, and their connection with the subarachnoid space. After infusion of 70 kD FITC-dextran into the cerebrospinal fluid via the cisterna magna, labeled PVS were evident around arteries, but veins showed less frequent labeling of the PVS. The size of the PVS correlated with blood vessel size for both pial arteries and veins, but not for penetrating vessels. The PVS around pial arteries and veins was separated from the subarachnoid space by a thin meningeal layer, which did not form a barrier for the tracer. In vivo, FITC-dextran signal was observed adjacent to the vessel wall, but minimally within the wall itself. Post-mortem, there was a significant shift in the tracer's location within the arterial wall, extending into the smooth muscle layer. Taken together, these findings suggest that the PVS around veins has a limited role in the exchange of solutes between CSF and brain parenchyma.
Subject(s)
Brain , Cerebral Arteries , Animals , Mice , Brain/blood supply , Cerebral Arteries/anatomy & histology , Glymphatic System , Fluorescein-5-isothiocyanate/analogs & derivatives , Dextrans , Male , Cerebral Veins/anatomy & histology , Mice, Inbred C57BL , Subarachnoid SpaceABSTRACT
Intracranial arterial anatomy is lacking for most mammalian and non-mammalian model species, especially concerning the origin of the basilar artery (BA). Enhancing the knowledge of this anatomy can improve animal models and help understanding anatomical variations in humans. We have studied encephalic arteries in three different species of birds and eight different species of mammals using formalin-fixed brains injected with arterial red latex. Our results and literature analysis indicate that, for all vertebrates, the internal carotid artery (ICA) supplies the brain and divides into two branches: a cranial and a caudal branch. The difference between vertebrates lies in the caudal branch of the ICA. For non-mammalian, the caudal branch is the origin of the BA, and the vertebral artery (VA) is not involved in brain supply. For mammals, the VA supplies encephalic arteries in two different ways. In the first type of organization, mostly found in ungulates, the carotid rete mirabile supplies the encephalic arteries, the caudal branch is the origin of the BA, and the VA is indirectly involved in carotid rete mirabile blood supply. The second type of encephalic artery organization for mammals is the same as in humans. The caudal branch of the ICA serves as the posterior communicating artery, and the BA originates from both VAs. We believe that knowledge of comparative anatomy of encephalic arteries contributes to a better understanding of animal models applicable to surgical or radiological techniques. It improves the understanding of rare encephalic variations that may be present in humans.
Subject(s)
Basilar Artery , Brain , Animals , Humans , Basilar Artery/anatomy & histology , Brain/anatomy & histology , Carotid Arteries/anatomy & histology , Vertebrates , Mammals , Carotid Artery, Internal/anatomy & histology , Cerebral Arteries/anatomy & histologyABSTRACT
The cerebral arteries, specifically the anterior cerebral artery (ACA) and posterior cerebral artery (PCA), work together with the smaller calibre arteries to provide effective communication between the anterior and posterior circuits of the brain via the circle of Willis (CoW). Morphologic variations of the cerebral arteries and the CoW may alter blood flow to the brain, resulting in intracranial vascular disorders associated with stroke, and aneurysms. This study aimed to document the morphology of the cerebral arteries and the CoW in the South African population. Two hundred and thirty-nine computed tomography angiography scans were assessed. Cerebral arteries and CoW normal morphology and variations were classified as complete, absent, or hypoplastic. The ACA A1 was absent in 4.91%, hypoplastic in 30.40%, fenestrated in 1.06%, and typical in 63.6%. The ACA A2 was absent in 0.42%, hypoplastic in 26.28%, and typical in 69.44%. We found triple ACA A2 in 2.98%, azygos in 1.28% and fenestrated in 1.28%. The middle cerebral artery (MCA) was hypoplastic in 7.35% and typical in 92.64%. The PCA was hypoplastic in 28.74% and typical in 71.25%. Knowledge of the configuration of the CoW plays a significant role in guiding therapeutic decision-making in treating various neurovascular pathologies.
Subject(s)
Brain , Cerebral Arteries , Humans , South Africa , Cerebral Arteries/diagnostic imaging , Cerebral Arteries/anatomy & histology , Brain/blood supply , Circle of Willis/diagnostic imaging , Middle Cerebral Artery , Cerebral AngiographyABSTRACT
BACKGROUND: The posterior cerebral arteries (PCAs) are terminal branches of the basilar artery (BA) and are responsible for the primary supply of the occipital lobe. Saccular aneurysm is most commonly seen close to the bifurcation of the BA. Various surgical interventions are performed for aneurysms. Therefore, the anatomy and localization of the BA and PCA are crucial. The aim of this study was to determine the characteristics of these arteries in a large Anatolian population. METHODS: The study included 170 Anatolian fresh cadavers. The diameters of the BA and PCA were measured. Correlations according to sex and age groups were analyzed. The Q1, Q2, and Q3 angles between the right and left PCA, between the right PCA and BA, and between the left PCA and BA, respectively, were measured. The location of the PCA relative to the sulcus pontocruralis (pontocrural groove) was also evaluated. RESULTS: The diameter of the artery increased with age and was higher in males than in females. Q1 and Q2 diameters were larger in males, while the Q3 diameter was larger in females. The Q1 angle between the right and left PCAs was found to be higher in age range 40-59 years with a mean of 87.33 ± 17.91 mm. Finally, the bifurcation point of the PCA was most frequently located above the sulcus pontocruralis (pontocrural groove) and least frequently located on the sulcus pontocruralis (pontocrural groove). CONCLUSIONS: The findings of our study will contribute to the planning of surgical approaches, the development of endovascular devices, the success of invasive procedures, and the reduction of complications.
Subject(s)
Intracranial Aneurysm , Posterior Cerebral Artery , Male , Female , Humans , Adult , Middle Aged , Posterior Cerebral Artery/anatomy & histology , Basilar Artery/surgery , Basilar Artery/anatomy & histology , Intracranial Aneurysm/surgery , Cerebral Arteries/surgery , Cerebral Arteries/anatomy & histologyABSTRACT
The present study was designed to provide a comprehensive analysis of the anatomical aspects of arterial blood vasculature in the water buffalo brains. Fifty cranial cavities of adult water buffaloes were opened via both the dorsal and ventral approaches and the arteries were exposed and photographed. The buffalo rostral epidural rete mirabile generally resembled that of large ruminants. The oculomotor, abducent and trigeminal nerves were intimately associated with the rostral rete. Similar to the majority of ruminants, the arterial circle of the brain was heart-shaped in buffalos and presented all collateral blood vessels as mentioned in the previous literature. The study further revealed that the cranial nerve roots were closely related to the arterial circle of the brain and could be used as indicators for differentiating various branches of the arterial circle of the brain. In addition to the usual variations of the arterial circle of the brain, a bihemispheric rostral cerebral artery along with an aplastic rostral cerebral artery were reported for the first time. The deviant behaviour of the rostral cerebral artery forms a baseline to study various clinical conditions of the blood vasculature in the buffalo brain. The rostral choroidal, middle cerebral and the caudal cerebral arteries constantly were emerged as single vessels without any variations. In conclusion, the anatomy of the arterial vasculature of the buffalo brain observed in the present study provided evidence of its morphological resemblance to other species of the Bovini tribe.
Subject(s)
Brain , Buffaloes , Animals , Brain/anatomy & histology , Cerebral Arteries/anatomy & histology , Cerebral Arteries/physiology , Cranial NervesABSTRACT
BACKGROUND AND PURPOSE: Brain arterial diameters are markers of cerebrovascular disease. Demographic and anatomical factors may influence arterial diameters. We hypothesize that age, sex, height, total cranial volume (TCV), and persistent fetal posterior cerebral artery (fPCA) correlate with brain arterial diameters across populations. METHODS: Participants had a time-of-flight MRA from nine international cohorts. Arterial diameters of the cavernous internal carotid arteries (ICA), middle cerebral arteries (MCA), and basilar artery (BA) were measured using LAVA software. Regression models assessed the association between exposures and brain arterial diameters. RESULTS: We included 6,518 participants (mean age: 70 ± 9 years; 41% men). Unilateral fPCA was present in 13.2% and bilateral in 3.2%. Larger ICA, MCA, and BA diameters correlated with older age (Weighted average [WA] per 10 years: 0.18 mm, 0.11 mm, and 0.12 mm), male sex (WA: 0.24 mm, 0.13 mm, and 0.21 mm), and TCV (WA: for one TCV standard deviation: 0.24 mm, 0.29 mm, and 0.18 mm). Unilateral and bilateral fPCAs showed a positive correlation with ICA diameters (WA: 0.39 mm and 0.73 mm) and negative correlation with BA diameters (WA: -0.88 mm and -1.73 mm). Regression models including age, sex, TCV, and fPCA explained on average 15%, 13%, and 25% of the ICA, MCA, and BA diameter interindividual variation, respectively. Using height instead of TCV as a surrogate of head size decreased the R-squared by 3% on average. CONCLUSION: Brain arterial diameters correlated with age, sex, TCV, and fPCA. These factors should be considered when defining abnormal diameter cutoffs across populations.
Subject(s)
Magnetic Resonance Angiography , Humans , Male , Female , Aged , Cohort Studies , Sex Factors , Age Factors , Middle Aged , Carotid Artery, Internal/anatomy & histology , Carotid Artery, Internal/diagnostic imaging , Middle Cerebral Artery/diagnostic imaging , Middle Cerebral Artery/anatomy & histology , Brain/diagnostic imaging , Brain/anatomy & histology , Posterior Cerebral Artery/diagnostic imaging , Posterior Cerebral Artery/anatomy & histology , Basilar Artery/diagnostic imaging , Basilar Artery/anatomy & histology , Aged, 80 and over , Cerebral Arteries/diagnostic imaging , Cerebral Arteries/anatomy & histologyABSTRACT
The irrigation of the thalamus depends mainly on the thalamoperforating arteries. There are many anatomical variations in these arteries, the best known being the artery of Percheron. We report a case of a 13-year-old male presented with headache and decline in his mental status. Imaging features showed obstructive hydrocephalus secondary to a mass at the level of the mesencephalon so an endoscopic third ventriculostomy was performed. During the procedure a thalamoperforating artery was encountered at the level of the tuber cinereum limiting the perforation of the third ventricle floor. The present case emphasizes the importance of knowing the anatomy of these arteries and the identification of their main variants during neurosurgical procedures (AU)
La irrigación talámica depende principalmente de las arterias talamoperforantes. Existen muchas variantes anatómicas en el origen y disposición de estas arterias siendo la más conocida la denominada arteria de Percheron. En este artículo presentamos el caso de un varón de 13 años que acudió a urgencias por cefalea y deterioro del nivel de consciencia. En las pruebas de imagen se evidenció una hidrocefalia obstructiva secundaria a una tumoración mesencefálica, motivo por el cual se decidió realizar una ventriculostomía endoscópica. Durante el procedimiento se evidenció una arteria talamoperforante a nivel del tuber cinereum que limitó la fenestración del suelo del tercer ventrículo. A partir de este caso destacamos la importancia de conocer la anatomía de estas arterias con sus posibles variantes y su identificación durante los procedimientos neuroquirúrgicos (AU)
Subject(s)
Humans , Male , Adult , Ventriculostomy/methods , Stroke/surgery , Cerebral Arteries/anatomy & histology , Cerebral Arteries/surgeryABSTRACT
BACKGROUND: The posterior cerebral artery (PCA) leaves from the distal end of the basilar artery (BA) and is joined to the internal carotid artery (ICA) by the posterior communicating artery (PComA). METHOD: The archived computed tomography angiogram of a 67 y.o. male patient was studied anatomically. RESULTS: Anatomically normal PCAs left the BA. Both anterior choroidal arteries were found but the right one was hyperplastic. As the latter distributed parieto-occipital and calcarine branches, it was regarded as an accessory PCA. It was laterally to the normal one, inferior to the vein of Rosenthal. CONCLUSION: The terms "accessory PCA" and "hyperplastic anterior choroidal artery" describe the same morphology. Rare anatomical variants could benefit from a homogenous terminology.
Subject(s)
Basilar Artery , Posterior Cerebral Artery , Male , Humans , Posterior Cerebral Artery/diagnostic imaging , Basilar Artery/anatomy & histology , Cerebral Arteries/anatomy & histology , Carotid Artery, Internal/diagnostic imaging , Carotid Artery, Internal/anatomy & histology , Circle of WillisABSTRACT
Stereotactic radiosurgery planning for cerebral arteriovenous malformations (AVM) is complicated by the variability in appearance of an AVM nidus across different imaging modalities. We developed a deep learning approach to automatically segment cerebrovascular-anatomical maps from multiple high-resolution magnetic resonance imaging/angiography (MRI/MRA) sequences in AVM patients, with the goal of facilitating target delineation. Twenty-three AVM patients who were evaluated for radiosurgery and underwent multi-parametric MRI/MRA were included. A hybrid semi-automated and manual approach was used to label MRI/MRAs with arteries, veins, brain parenchyma, cerebral spinal fluid (CSF), and embolized vessels. Next, these labels were used to train a convolutional neural network to perform this task. Imaging from 17 patients (6362 image slices) was used for training, and 6 patients (1224 slices) for validation. Performance was evaluated by Dice Similarity Coefficient (DSC). Classification performance was good for arteries, veins, brain parenchyma, and CSF, with DSCs of 0.86, 0.91, 0.98, and 0.91, respectively in the validation image set. Performance was lower for embolized vessels, with a DSC of 0.75. This demonstrates the proof of principle that accurate, high-resolution cerebrovascular-anatomical maps can be generated from multiparametric MRI/MRA. Clinical validation of their utility in radiosurgery planning is warranted.
Subject(s)
Cerebral Angiography/methods , Cerebral Arteries/diagnostic imaging , Cerebral Veins/diagnostic imaging , Deep Learning , Intracranial Arteriovenous Malformations/surgery , Magnetic Resonance Angiography/methods , Multiparametric Magnetic Resonance Imaging/methods , Radiosurgery/methods , Cerebral Arteries/anatomy & histology , Cerebral Veins/anatomy & histology , HumansABSTRACT
RESUMEN: El círculo arterial cerebral (CAC) mencionado también como polígono de Willis es una red de anastomosis vascular situado en la base del cerebro, constituido por ramas de la arteria carótida interna (ACI) y del sistema vertebro-basilar. Este estudio evaluó la morfología de las arterias que conforman el CAC en una muestra de individuos colombianos. Previa canalización de la ACI y de la arteria vertebral (AV), se perfundió con resina poliéster (palatal 85 % y estireno 15 %) los lechos vasculares del CAC de 70 encéfalos extraídos de cadáveres a quienes se les practicó necropsia en el Instituto de Medicina Legal de Bucaramanga, Colombia. La arteria comunicante anterior (ACoA) se observó en 68 encéfalos (97,1 %), con ausencia en 2 de las muestras (2,9 %); en promedio su diámetro fue de 1,91?1,04 mm y su longitud 2,21?0,97 mm respectivamente. Asimismo, se encontró hipoplasia en 6 muestras (8,4 %). La arteria comunicante posterior (ACoP) estuvo ausente en 2 de las muestras (5,7 %); su longitud fue 11,63?2,12 mm, mientras que su calibre fue de 1,21?0,58 mm, siendo ligeramente mayor en el lado derecho, sin diferencias estadísticamente significativas con relación al lado de presentación (p= 0,763). Se encontró hipoplasia de la ACoP en forma bilateral en 19 de las muestras (27,1 %) y unilateral en 15 muestras (21,4 %). En 8 muestras (20 %) de 35 CAC evaluados se observó configuración fetal. La incidencia de hipoplasia de la ACoP y de configuración fetal encontrados en el presente estudio, se ubican en el segmento superior de lo reportado en la literatura. Estas expresiones morfológicas han sido consideradas como coadyuvantes en el desarrollo de accidentes cerebro-vasculares (ACV).
SUMMARY: The cerebral arterial circle (CAC), also referred to as the polygon of Willis is a network of vascular anastomoses located at the base of the brain, consisting of branches of the internal carotid artery (ICA) and the vertebrobasilar system (VBS). This study evaluated the morphology of the arteries forming the CAC in a sample of Colombian individuals. After cannulation of the ICA and the vertebral artery (VA), the vascular beds of the ACC of 70 brains extracted from cadavers at the Institute of Legal Medicine of Bucaramanga, Colombia, were perfused with polyester resin (85 % palatal and 15 % styrene). The anterior communicating artery (ACoA) was observed in 68 brains (97.1 %), with absence in 2 of the samples (2.9 %); on average its diameter was 1.91?1.04mm and its length 2.21?0.97mm respectively. Likewise, hypoplasia was found in 6 samples (8.4 %). The posterior communicating artery (ACoP) was absent in 2 of the samples (5,7 %); its length was 11.63?2.12mm, while its caliber was 1.21?0.58mm, being slightly larger on the right side, with no statistically significant differences in relation to the side of presentation (p= 0.763). Hypoplasia of the ACoP was found bilaterally in 19 of the samples (27.1 %) and unilaterally in 15 samples (21.4 %). Fetal configuration was observed in 8 samples (20 %) of 35 CACs evaluated. The incidence of ACoP hypoplasia and fetal configuration found in the present study are in the upper segment of those reported in the literature. These morphological expressions have been considered as coadjuvants in the development of cerebrovascular accidents (CVA).
Subject(s)
Humans , Male , Adolescent , Adult , Middle Aged , Aged , Young Adult , Brain/blood supply , Circle of Willis/anatomy & histology , Anatomic Variation , Cadaver , Cerebral Arteries/anatomy & histology , ColombiaABSTRACT
The corticospinal tract (CST) is the main neural pathway responsible for conducting voluntary motor function in the central nervous system. The CST condenses into fiber bundles as it descends from the frontoparietal cortex, traveling down to terminate at the anterior horn of the spinal cord. The CST is at risk of injury from vascular insult from strokes and during neurosurgical procedures. The aim of this article is to identify and describe the vasculature associated with the CST from the cortex to the medulla. Dissection of cadaveric specimens was carried out in a manner, which exposed and preserved the fiber tracts of the CST, as well as the arterial systems that supply them. At the level of the motor cortex, the CST is supplied by terminal branches of the anterior cerebral artery and middle cerebral artery. The white matter tracts of the corona radiata and internal capsule are supplied by small perforators including the lenticulostriate arteries and branches of the anterior choroidal artery. In the brainstem, the CST is supplied by anterior perforating branches from the basilar and vertebral arteries. The caudal portions of the CST in the medulla are supplied by the anterior spinal artery, which branches from the vertebral arteries. The non-anastomotic nature of the vessel systems of the CST highlights the importance of their preservation during neurosurgical procedures. Anatomical knowledge of the CST is paramount to clinical diagnosis and treatment of heterogeneity of neurodegenerative, neuroinflammatory, cerebrovascular, and skull base tumors.
Subject(s)
Brain Stem/blood supply , Cerebral Arteries/anatomy & histology , Cerebral Cortex/blood supply , Pyramidal Tracts/blood supply , Aged , Cadaver , Female , Humans , Male , Middle Aged , Neurosurgical Procedures , Stroke/physiopathologyABSTRACT
The anatomic distribution of the deep cerebral perforators is considered either a given or subject to enormous variability. Most published overviews on this topic only report findings from a limited number of anatomic dissections, and no attempt has been made to date to provide a comprehensive overview of all published data. A comprehensive literature search was performed on MEDLINE, Embase, and Google Scholar with the help of an information specialist. Three types of studies were included: (1) articles that described the anatomy and distribution territories of perforator groups arising from the arteries of the circle of Willis; (2) studies that evaluated the anatomy of the deep cerebral perforators using imaging techniques; and (3) studies that evaluated either microsurgically or radiologically confirmed perforator occlusion and reported the (magnetic resonance imaging-confirmed) distribution territory of the infarction together with a description of the clinical symptoms associated as a result of the infarction. A total of 2715 articles were screened and 53 were included. Of these, 40 dealt with the anatomic and imaging anatomy of perforator groups (37 reported results of dissections and 3 results of imaging studies), with a total of 2421 hemispheres investigated. Another 13 articles with 680 patients were included that evaluated perforator infarction territories. The deep cerebral perforator distribution shows large variability with poor concordance rates among reported studies, with the exception of the posterior communicating and anterior choroidal artery perforators. Despite the assumption that cerebral perforator anatomy is a given, studies show large variability in the anatomic distribution of various perforator groups. Perforator anatomy and relationships between perforator groups, as well as potential collateral circulation in these territories should be prioritized as a research topic in cerebrovascular disease in the near future.
Subject(s)
Cerebral Arteries/anatomy & histology , Cerebral Arteries/physiology , Cerebrovascular Circulation/physiology , Animals , Arterial Occlusive Diseases , Carotid Artery, Internal , Cerebral Arteries/diagnostic imaging , Collateral Circulation , Humans , Magnetic Resonance ImagingABSTRACT
BACKGROUND: Enterprise stents are widely used for intracranial aneurysms located on small arteries (<2.5 mm in diameter) and change the geometry of parent arteries. The purpose of this study was to investigate the correlation between vascular geometry changes and long-term outcomes. METHODS: Between May 2013 and 2018, 1065 consecutive intracranial aneurysms were treated with Enterprise stents at our institution. After inclusion and exclusion criteria were applied, 377 aneurysms with >6 months of digital subtraction angiography follow-up were evaluated. The cohort comprised 101 aneurysms located on small parent arteries. After stent-assisted coiling, the vascular geometry parameters of small parent arteries were compared to explore their correlation with procedural complications, delayed stent migration, and recanalization. RESULTS: The rate of delayed aneurysm occlusion in patients with initial efferent artery diameter (De) <2.5 mm was significantly higher than in patients with De >2.5 mm (62.2% vs. 40.2%; P = 0.032). At follow-up, vascular geometry parameters significantly increased (P < 0.001). In multivariate analyses, larger aneurysms and initial parent artery angle (α) <90° were independent predictors of procedural complications and discrepancy in vessel size (ΔD) >0.5 mm was an independent predictor of delayed stent migration. Larger aneurysms and follow-up angle change (ΔAngle) <30° were independent predictors for recanalization of aneurysms located on small arteries. CONCLUSIONS: Enterprise stent-assisted coiling of intracranial aneurysms located on small arteries is safe and effective. Our study found that Enterprise deployment in small arteries had a low procedural complication rate and high stent tolerance. Vascular geometry changes play an important role in aneurysm recanalization.
Subject(s)
Cerebral Arteries/diagnostic imaging , Intracranial Aneurysm/surgery , Stents , Adult , Aged , Angiography, Digital Subtraction , Cerebral Angiography , Cerebral Arteries/anatomy & histology , Endovascular Procedures/methods , Female , Humans , Male , Middle Aged , Prosthesis Failure , Treatment OutcomeABSTRACT
Supratentorial sensory perception, including pain, is subserved by the trigeminal nerve, in particular, by the branches of its ophthalmic division, which provide an extensive innervation of the dura mater and of the major brain blood vessels. In addition, contrary to previous assumptions, studies on awake patients during surgery have demonstrated that the mechanical stimulation of the pia mater and small cerebral vessels can also produce pain. The trigeminovascular system, located at the interface between the nervous and vascular systems, is therefore perfectly positioned to detect sensory inputs and influence blood flow regulation. Despite the fact that it remains only partially understood, the trigeminovascular system is most probably involved in several pathologies, including very frequent ones such as migraine, or other severe conditions, such as subarachnoid haemorrhage. The incomplete knowledge about the exact roles of the trigeminal system in headache, blood flow regulation, blood barrier permeability and trigemino-cardiac reflex warrants for an increased investigation of the anatomy and physiology of the trigeminal system. This translational review aims at presenting comprehensive information about the dural and brain afferents of the trigeminovascular system, in order to improve the understanding of trigeminal cranial sensory perception and to spark a new field of exploration for headache and other brain diseases.
Subject(s)
Brain/anatomy & histology , Cerebral Arteries/anatomy & histology , Dura Mater/anatomy & histology , Headache/etiology , Trigeminal Nerve/anatomy & histology , HumansABSTRACT
Type 1 diabetes is a chronic autoimmune disease that affects tens of millions of people. Diabetes mellitus is one of the strongest factors in the development of cerebrovascular diseases. In this study we used NOD.CB17 Prkdcscid mice and the pharmacological model of type 1 diabetes mellitus of different duration to study changes in the cerebral vasculature. We used two combined approaches using magnetic resonance angiography both steady and transient CFD blood flow modeling. We identified the influence of type 1 diabetes on the architectonics and hemodynamics of the large blood vessels of the brain as the disease progresses. For the first time, we detected a statistically significant change in angioarchitectonics (the angles between the vessels of the circle of Willis, cross-sections areas of vessels) and hemodynamic (maximum blood flow rate, hydraulic resistance) in animals with diabetes duration of 2 months, that is manifested by the development of asymmetry of cerebral blood flow. The result shows the negative effect of diabetes on cerebral circulation as well as the practicability of CFD modeling. This may be of extensive interest, in pharmacological and preclinical studies.
Subject(s)
Cerebral Arteries/physiology , Cerebrovascular Circulation/physiology , Diabetes Mellitus, Type 1/physiopathology , Animals , Brain/physiology , Cerebral Arteries/anatomy & histology , Diabetes Mellitus, Type 1/metabolism , Disease Models, Animal , Hemodynamics/physiology , Magnetic Resonance Angiography/methods , Male , Mice , Mice, Inbred NODABSTRACT
The chiasmal and subchiasmal surfaces are of critical importance in connection with the performance of surgical procedures owing to the critical blood supply to these areas. Recently, the perforating arteries providing the blood to the optic nerves and chiasm have gained attention as they significantly affect the morbidity from surgical approaches. Intraoperative preservation of these perforating arteries is considered critical to prevent further visual loss. Thirty autopsy specimens, including the optic apparatus, were examined for their perforating arteries feeding the optic chiasm and optic nerves. The optic nerves and chiasmal surfaces were divided into four zones based on the presence and numbers of perforating arteries as anterior superior-posterior superior surfaces and anterior inferior-posterior inferior surfaces. The superior surface of the optic chiasm was supplied by the A1 segments of the bilateral anterior cerebral arteries and by the perforating arteries originating from the anterior communicating artery. On the other hand, the inferior surface of the optic chiasm was fed by the bilateral posterior communicating arteries and by the supraclinoidal segments of the bilateral carotid arteries. We demonstrated the anatomical involvement of a large number of nourishing arteries in feeding the optic apparatus related to the perforating arteries by classifying them into zones based on the surgical approaches, which has been rarely reported in the literature.
Subject(s)
Cerebral Arteries/anatomy & histology , Circle of Willis/anatomy & histology , Optic Chiasm/blood supply , Optic Nerve/blood supply , Cadaver , HumansABSTRACT
Brain specimens from 30 ostriches were injected with red-dyed latex via the internal carotid arteries (Aa.). The ventral tectal mesencephalic artery (a.), invariably a medium-sized single vessel, was, on the right side, a collateral branch of the caudal branch of the carotid artery (53.4%), a direct branch of the carotid artery (43.3%) and a direct branch of the basilar artery (3.3%) and on the left side, a collateral branch of the caudal branch of the carotid artery (66.7%), a direct branch of the carotid artery (30%), and a direct branch of the basilar artery (3.3%). It vascularized only the ventral half of the optic lobe, with no involvement in cerebellar vascularization on the right (93.3%) and left (80%) sides, extending to the ventrorostral-most cerebellar lobules, which were vascularized on the right (6.7%) and left (20%) sides. The caudal ventral cerebellar arteries were a single vessel on the right (96.7%) and left (93.3%) sides. Its first branch was a common trunk: dorsal spinal-caudal cerebellar on the right (60%) and left (56.6%) sides. Its second branch was the caudal cerebellar artery on the right (76.7%) and left (86.7%) sides. Its third branch was the second component of the caudal cerebellar artery on the right (6.7%) and left (3.3%) sides. The midbrain was vascularized by dorsal and ventral tectal mesencephalic arteries. The cerebellum was vascularized by branches of the caudal ventral cerebellar artery and by the dorsal cerebellar artery.
Subject(s)
Carotid Artery, Internal/anatomy & histology , Cerebral Arteries/anatomy & histology , Mesencephalon/blood supply , Rhombencephalon/blood supply , Struthioniformes/anatomy & histology , AnimalsABSTRACT
The brain and kidney both uniquely are highly susceptible to vascular injury from shared vascular risk factors. However these are not sufficient to explain the complete extent of cerebrovascular disease especially small vessel disease in its myriad presentations that patients with chronic kidney disease manifest. They both require a large amount of blood supply to function optimally. Shared anatomical and physiological factors such as the presence of strain vessels, the local vascular autoregulation that control blood supply possible, results in the vulnerability of these organs to the vascular risk factors. Because it is a bidirectional system where each affects the other, it is best considered as a cerebro-renal unit.
Subject(s)
Brain/blood supply , Cerebral Arteries/physiology , Cerebrovascular Circulation , Kidney/blood supply , Renal Artery/physiology , Renal Circulation , Animals , Cerebral Arteries/anatomy & histology , Cerebral Small Vessel Diseases/etiology , Cerebral Small Vessel Diseases/pathology , Cerebral Small Vessel Diseases/physiopathology , Glymphatic System/physiology , Homeostasis , Humans , Models, Cardiovascular , Renal Artery/anatomy & histology , Renal Insufficiency, Chronic/complications , Renal Insufficiency, Chronic/pathology , Renal Insufficiency, Chronic/physiopathology , Risk FactorsABSTRACT
Bilateral thalamic infarctions are uncommon and often lead to more severe and long-lasting symptoms than unilateral thalamic infarctions. This article describes a patient with bilateral thalamic infarction caused by occlusion in the artery of Percheron, an anatomic variant thought to be present in 4% to 12% of the population.
Subject(s)
Anatomic Variation , Arterial Occlusive Diseases/etiology , Cerebral Arteries/anatomy & histology , Cerebral Infarction/etiology , Thalamus/blood supply , Arterial Occlusive Diseases/diagnosis , Cerebral Infarction/diagnosis , Humans , Male , Middle AgedABSTRACT
The Anterior Choroidal Artery (AChA), the Lateral Posterior Choroidal (LPChA) and the Medial Posterior Choroidal Arteries (MPChA) provide blood supply to the choroid plexus of the lateral ventricle and third ventricle. The objective of this study was to evaluate the morphology of the choroidal arteries in 74 unclaimed male cadavers, who under-went necropsy at the Institute of Legal Medicine and Forensic Sciences of Bucaramanga, Colombia. The AChA originated from the Internal Carotid Artery (ICA) in 96.6% of the cases, with a length of 10.1 ± 1.5 mm and 15.2 ± 1.7 mm for its pre-optic and post-optic segments respectively and had a diameter of 0.6 ± 0.16mm. The AChA originated branches to the optic tract (5.2), the anterior and posterior segment of the uncus of the hippocampus (3.4 and 2.4) and cerebral peduncles (2.6), before penetrating through the choroidal fissure. The MPChA originated from the pre-communicating segment of the posterior cerebral artery (ACP) in 97 cases (70.3%), its length was 38.1 ± 5.85 mm and its diameter 0.4 ± 0.14 mm; in three cases (2.2%) it was doubled. 46.3% of the MPChA presented proximal bifurcation at 8.7 ± 5.47 mm of their ACP origin, but in 17 cases (26.6%) an early bifurcation was found (less than 5 mm). The LPChA originated in the post-communicating segment (94.2%), without significant differences in presentation side (p = 0.189). Its length was 37.6 ± 7 mm and its diameter 0.5 ± 0.16 mm. The findings related to the site of origin, global dimensions and branches of the choroidal arteries observed in the present study are consistent with those reported in other population groups. This study, carried out in cadaveric material, provides relevant qualitative and morphometric information of the choroidal arteries, useful for diagnosis and clinical management, as well as for surgical approaches that may compromise this structure
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