Microanatomic Study of the Optic Canal.

BACKGROUND: The continuous development of microsurgical techniques to treat lesions in and around the optic canal (OC) emphasizes the need for an accurate understanding of the microanatomy of the region. METHODS: Forty anatomic specimens were studied, with emphasis on the OC. The sphenoid bone and related structures were decalcified, added to animal gelatin, cut into 1-mm thick slices, and observed through a surgical microscope. The OC was considered the course that contained exclusively the optic nerve (ON) and ophthalmic artery. RESULTS: The mean distance between the medial walls of the OC was 12.2 mm, and the OC had an average length of 12.06 mm. The OC has a horizontal oval shape in the proximal (internal) segment; a round shape in the middle segment; and a vertical oval shape in the distal (external) segment at the orbital cavity. In the middle segment of the OC, the thickest wall of the OC was the lateral (average: 0.68 mm), while the medial, inferior, and superior wall measures had averages of 0.75, 0.40, and 0.39 mm, respectively. The lateral wall of the sphenoid sinus is located under the OC, and the inferior wall of the OC separates both structures. The ophthalmic artery inside the OC was always located under the ON, between the dural sheaths, and had an average diameter of 1.03 mm. CONCLUSIONS: The neurovascular structures within the OC vary in size and shape. The anatomic knowledge of the OC and its variations allows better surgical results and minimizes the surgical morbidity.

Delayed diagnosis of intracranial aneurysm in pediatrics: the risk of misdiagnosis-a case report.

BACKGROUND: Aneurysms in the pediatric population are uncommon, requiring a high index of suspicion for diagnosis. We report a case of a child with head trauma and delayed diagnosed cerebral aneurysm. METHODS: A 2-year-old girl was brought to the emergency room with seizures. Head imaging showed acute intraventricular hemorrhage, hydrocephalus, and paraclinoid aneurysm of the right internal carotid artery. She had been hospitalized elsewhere 1 month prior for traumatic brain injury after falling to the ground with subarachnoid and intraventricular hemorrhage and good recovery, but without diagnosis of aneurysm. RESULTS: The child was treated with aneurysm embolization and ventriculoperitoneal shunt, being discharged asymptomatic. CONCLUSION: Most primary intraventricular hemorrhage in pediatric population has identifiable etiology. A high rate of clinical suspicion, associated with a low threshold for vascular neuroimaging studies for children with spontaneous or atypical intracranial hemorrhage allow accurate diagnosis, appropriate treatment, and improved outcome.

Intraventricular hemorrhage secondary to AVM of the septum pellucidum / Hemorragia intraventricular secundária a MAV de septum pellucidum

Arteriovenous malformations (AVMs) of the brain include congenital vascular lesions that represent about 2% of all hemorrhagic strokes. Despite the relative rarity of the disease (with a detection rate estimated at approximately 1/100.000 person-years), AVMs represent a significant neurological problem. Affected patients are mostly young and healthy. AVMs located in the medial region of the cerebral hemisphere and the limbic system comprise a special group with difficult access and consequent difficulties of resection. Furthermore, there is a high incidence of intracranial hemorrhage resulting from a complex venous drainage, sometimes directed to the superficial veins, but mostly to the deep venous system. The present case report illustrates a patient with an AVM centered on the septum pellucidum, whose initial clinical resulted from an intra-ventricular hemorrhage.

Malformações arteriovenosas (MAVs) encefálicas são lesões vasculares congênitas que representam cerca de 2% de todos os acidentes vasculares hemorrágicos. Embora se tratando de uma doença relativamente rara (com prevalência estimada em aproximadamente 1/100.000 pessoas-ano), MAVs representam um problema neurológico significativo. Os pacientes afetados são na maioria jovens e hígidos. MAVs localizadas na região medial do hemisfério cerebral e no sistema límbico correspondem a um grupo especial pela dificuldade de acesso e consequente dificuldade de ressecção. Além disso, possuem alta incidência de hemorragia intracraniana resultante de uma drenagem venosa complexa, por vezes direta às veias superficiais, mas na maioria para os sistemas venosos profundos. O caso relatado a seguir ilustra um paciente com uma MAV centrada no septum pellucidum, cuja apresentação clínica inicial resultou de uma hemorragia intraventricular.

Acrania e outras falhas na formação dos ossos do crânio: uma revisão da literatura / Acrania and other failures in the formation of the skull bones: a literature review

A acrania é uma malformação congênita rara que cursa com ausência parcial ou total do crânio de fetos humanos. Está associada frequentemente com anencefalia e é, via de regra, fatal em curtíssimo prazo. Existem alguns marcadores pré-natais, sendo a ultrassonografia o exame diagnóstico padrão-ouro. Os autores revisam aspectos relacionados a epidemiologia, fisiopatologia, diagnóstico ultrassonográfico, diagnóstico diferencial entre malformações cefálicas e manejo obstétrico da doença.

Acrania is a rare congenital malformation with partial ortotal absence of skull of human fetuses. It is often associatedwith anencephaly and is usually fatal in very short time.There are some prenatal markers and the ultrasound is thegold-standard diagnostic method. The authors review aspectsof the epidemiology, pathophysiology, ultrasound diagnosis,differential diagnosis of cephalic malformations and obstetricmanagement of the disease.