Descriptive and topographical analysis of the labyrinthine artery in human fetuses.

Hearing or/and balance impairments may be caused by disorders of the labyrinthine artery (LA) and their branches. Most findings regarding the LA anatomy have been acquired through investigation of the cerebellopontine angle (CPA) in animal or adult human specimens. Eighty-eight CPAs and LAs of human fetuses were investigated using angio-techniques and microdissections. We found 15 intricate forms of distribution of LA. The LA usually originated from the extra-meatus loop in the anterior inferior cerebellar artery (AICA). The distribution of its terminal branches was 53.42% uni-arterial, 44.31% bi-arterial, and 2.27% tri-arterial systems. In the uni-arterial system, the LA described an anterior superior path to the cochlear nerve (CN) and originated its terminal branches in the gap between CN and the inferior part of the vestibular nerve. In the bi-arterial system, the anterior LA was located anterior and superior to the CN while the posterior LA appeared posterosuperior to the superior part of the vestibular nerve. In the tri-arterial system, the terminal branches originated directly from the AICA loop. Our results provide anatomical support to explain how compressions in the LA branches inside the internal acoustic meatus, as evoked by Schwannomas in the VII and VIII nerves, can lead to hearing and balance loss. The zone of the posterior vestibular nerve appeared to be a "safe area" for invasive procedures in these specimens.

Accessory soleus muscle: a case report and clinical applicability.

Variations in leg muscle are uncommon. Literature on this subject is scarce, but when those variations are reported they may cause alterations in joint mechanics or cause some discomfort in the leg and foot. The accessory soleus muscle (ASM) is considered an unusual anatomical variation, with an incidence of 0.5-6.0% in the population through studies in cadavers. During routine preparation of study material in the dissection room of the anatomy laboratory of the Escola Superior de Ciências da Santa Casa de Misericórdia de Vitória/ES - Brazil, an ASM was found in the right inferior limb of a male cadaver fixed in 10% formalin. This supernumerary muscle was 3 cm wide, 9 cm long and 1 cm thick in its most voluminous part, in typical penniform fibers arrangement. It was located in the posteromedial region of the ankle, anterior to the Achilles tendon and posterior to the deep muscles of the leg compartment. Its anterior face covered the tibial nerve and the posterior tibial vessels, while its lower half was covered by the flexor retinaculum into the tarsal tunnel. Reports in the literature show possible compression of a neurovascular bundle because of its intimal position within the tarsal tunnel, which could result in ischemic compartment syndrome.

Anatomical study of the anterior interventricular septal branches and their relationship with the blood supply of the septomarginal trabecula

The aim of this study was to examine the morphological features of the anterior interventricular septal branches that supply blood to the septomarginal trabecula and to correlate the anatomical observations with the angiographic characteristics analyzed by hemodynamic procedures. Forty human hearts were dissected after injecting colored latex into the left coronary artery. The vascularization of the septomarginal trabecula was always derived from the anterior interventricular artery, via the first, second and third anterior interventricular septal branches in 21 hearts (52.5%), 17 hearts (42.5%) and two hearts (5%), respectively, and the distances from the left coronary artery ostium ranged from 22 to 51 mm. The external diameter of these vessels at their origin varied from 1.0 to 2.35 mm and the vessels were analyzed based on specific requirements for surgical and hemodynamic methods of myocardial revascularization. Myocardial bridges were located over or before the origin of the vessels studied.

Pectoralis minor muscle. An unusual insertion

Variations in the insertion of the pectoralis minor muscle have been described. Although much of them were considered to be functionally normal, others may be associated in certain with disconfort related to shoulder movement. Here we described a bilateral, symmetric insertional variation of the pectoralis minor muscle that was found during a routine dissection of upper limbs. In this variation, the tendon crossed the superior surface of the coracoid process to insert on the major tubercle of the humerus head, where it fused with the tendon of the supraspinatus muscle. This variation could be the cause of pain during certain shoulder movements as a result of neurovascular compression, and may lead to mechanical alterations in the muscular dynamics of the shoulder.

Morphological aspects of the distal medial striated artery (artery of Heubner)

The distal medial striated artery, one of the branches of the anterior complex of the circle of Willis, is important because it supplies the caudate nucleus and adjoining putamen, part of the septal nucleus and fibers of the anterior part of the internal capsule. This vessel situated in a region often dealt with in neurological surgeries and can be injured because of its anatomical relationship with important structures in this region. In this study, we examined the anatomical arrangement in 50 human brains fixed in 20 per cent formaldehyde solution. The origin of this vessel was assessed relative to the pre-, post- and communicating segments of the anterior cerebral artery. Of the 121 arteries found, 49.6 per cent arose from the post-communicating segment and were duplicated in 50.4 per cent of the cases, single in 49.6 per cent and symmetrical in 44.5 per cent. The distal medial striated artery was absent in only one specimen. In relation to the pre-communicating segment, the course of this artery was anterior in 77 per cent of the cases, superior in 20 per cent and posterior in 3 per cent. A division of the anterior perforated substance into anterior, lateral and medial regions served to locate the terminal branches of the artery. The terminal branches penetrated the anterior, lateral and medial regions in 48.8 per cent, 47 per cent and 4.3 per cent of the cases respectively.

Morphology and blood supply of papillary muscle in the arterial conus

The morphology and position of the papillary muscle of the arterial conus were studied in 50 human hearts of both sexes. In 40 hearts, the interventricular anterior and posterior arteries were filled with vinyl acetate to study the blood supply. the muscle lenght varied from 4 mm to 18 mm and the base of implantation was located between the anterobasal and posterobasal limbs of the septomarginal trabecula. The most frequent forms of muscle presentation were an attached conus (68 porcento of cases(, a free conus (10 porcento) and a double conus (6 porcento). the blood supply was derived from the first, second and third septal interventricular branches of the anterior interventricular artery in 75 porcento, 22.5 porcento and 2.5 porcento of the cases, respectively. Since the term "papillary muscle of the arterial conus"is not a standard anatomical term, and since "septal papillary muscle"does not clearly define the muscle position in the septal wall of the right ventricle, new terminology is required to accurately describe the septal papillary muscles of the right ventricle.

The blood of the papillary muscle of the right ventricle of human heart and its relationship with the ventricular arterial segments

The frequency of the blood supply of the right ventricle papillary muscles was studied in 41 humans heartsinjected with a vinyl acetate solution. The anterior interventricular branch (AIV), right marginal branch (RM) and posterior interventricular branch (PIV) were injected with different colors and correlated with the arterial segments of the heart (I SV, II DV and III DV) supplied by each one of those arteries. The anterior and posterior papillary muscles received blood from the three arterial segments. The artery of the segment I SV supplied the anterior papillary muscle in 56.09 (per cent) of the cases. The posterior papillary muscle was supplied by the artery of the segment II DV in 34.14 (per cent) of the cases. The anterior group of the septal papillary muscle was supplied by the artery of the segment I SV in all cases. When the posterior group of septal papillary muscle was present (29 cases), the blood supply came from the arteries of the three segments, with major contribution from the arteries of the segments I SV (31.03 per cent) and III DV (51.72 per cent). The most frequent associations observed were the segments I SV and II DV supplying the anterior papillary muscle (24.39 per cent) and segments II DV and III DV supplying the posterior papillary muscle (24.39 per cent).

Avaliaçäo morfométrica de neurônios secretores hormonais dos núcleos paraventriculares do Gallus domesticus, sob bloqueio do influxo de cálcio / Morphometric evaluation on hormonal secretory neurons of the paraventricular nucleus in Gallus domesticus, on obstruction of calcium influx

Parâmetros entre o transporte anterógrado e os níveis de cálcio foram demonstrados em neurônios isolados, e somam-se informaçoes que o fluxo axoplasmático pode estar relacionado com microtúbulos, miosina e actina em neurônios secretores hipotalâmicos. Neste estágio, procuramos verificar se há suscetilidade dos núcleos paraventrículares à açao do bloqueador de canais de cálcio (verapamil) e a decorrência do efeito sobre o transporte axoplasmático da neurossecreçao em Gallus domesticus aos 25 dias após eclosao. Os resultados da análise morfométrica com integralizador de imagem realizada após processamento segundo Bargmann e os da avaliaçao do teor proteico hipotalâmico pelo método de Lowry, foram analisados estatisticamente registrando consistência na hipótese de ser cálcio-dependente o transporte da neurossecreçao dos núcleos paraventriculares, nesta condiçao experimental.

Aspectos anatômicos e histológicos das glândulas peri-anais da cuíca Philander opossum Linnaeus, 1758 / Anatomic and histological aspects of the perianal glands of the four-eyed Philander opossum Linnaeus, 1758

Foram estudados os aspectos morfológicos das glândulas perianais da cuíca Philander opossum: Estes marsupiais apresentam dois pares de glândulas perianais situadas respectivamente à direita e à esquerda do ânus. Cada par está formado por uma glândula lateral e outra medial. Estas glândulas estäo alojadas na fossa ísquio-retal, sob a pele da regiäo perianal, sendo a glândula medial de coloraçäo perolácea e menor que a glândula lateral, que é de coloraçäo ocre. Cada uma destas glândulas está formada pela associaçäo de vários lóbulos interligados e envolvidos pela mesma cápsula fibro-muscular. Os ductos menores da glândula medial se reúnem formando um ducto principal único antes destes emergir na superfície da glândula. Os ductos menores da glândula lateral emergem separados na sua superfície, indo se reunir mais à frente, formando o ducto principal desta glândula. Os ductos principais de ambas as glândulas correm paralelos até próximo ao ânus, onde se fundem em um ducto comum que se abre na fosseta anal, distalmente à linha pectinada. O epitélio secretor destas glândulas apresenta características de secreçäo holócrina

Correlaçäo entre a mesoscopia e a microscopia dos germes dos dentes decíduos em fetos humanos / Correlation between mesoscopic and microscopic aspect of deciduos teeth in human fetus

Utilizando fetos humanos a termo, fixados em formol a 10% através de perfusäo pela veia umbilical, os autores desenvolveram pesquisa de cunho essencialmente didático, mostrando a correlaçäo entre o aspecto mesoscópico das estruturas formadoras dos dentes decíduos. Metades esquerdas de mandibulas desmineralizadas (......) foram também feitos cortes de sentido vestíbulo lingual passando através dos dentes, os quais serviram de comparaçäo com cortes histológicos semelhantes, feitos de material do mesmo feto. Este mostrou ser de fácil execuçäo, de baixo custo e de grande utilidade no ensino da embriologia oral