Anterior basal encephalocele of the neonatal and infantile period.

Diagnosis of occult basal encephalocele is not difficult if the peculiar clinical and radiological signs of this anomaly are borne in mind. Recent surgery for transsphenoidal encephalocele has had better results than realized. However, high surgical risks may still be encountered in transsphenoidal encephalocele of the early infantile period, because the pituitary-hypothalamic structures are usually incorporated in the herniated encephalocele of this age group. Surgical indications for and operative approaches to transsphenoidal encephalocele in the infantile period are discussed on the basis of the authors' failure in transcranial repair, which resulted in early postoperative death due to hypothalamic dysfunction. Reviewing the reported cases of anterior basal encephalocele, a high correlation between transsphenoidal encephalocele, particularly in the pediatric age group, and allied malformations of the face, eye, and brain was disclosed. This characteristic malformation complex may be explained by a common pathogenetic mechanism operating in the embryonal period at about the stage of the anterior neuropore closure and occurring in the ventral surface of the cephalic end of the neural tube. Three cases of transsphenoidal encephalocele diagnosed in the neonatal period with progressive obstruction in the nasopharyngeal airway are also reported. A characteristic malformation complex consisting of median cleft face syndrome, optic nerve dysplasia, and agenesis of the corpus callosum was associated in two cases; the other patient had an extremely rare combination of septooptic dysplasia. Two patients died pre- and postoperatively, respectively; the other patient did not undergo operation because of grave multiple anomalies.

Parietal cephalocele: clinical importance of its atretic form and associated malformations.

In this study of atretic cephaloceles, the authors have considered the pedunculated or sessile type of cephalocele and also small nonpedunculated scalp defects developing in the vertex midline. Parietal cephaloceles were found in 15 infants (10 boys and five girls), and accounted for 37.5% of all cephaloceles. They consisted of four encephaloceles, six meningoceles, and five atretic cephaloceles. The clinical and morphological characteristics of parietal cephaloceles were investigated and compared with those arising at other locations. Parietal cephaloceles carried a much less favorable prognosis than those in the occipital region, regardless of the type of cephalocele; they were associated with cerebral malformations more frequently and were more severe than occipital cephaloceles. Grave congenital anomalies were found in 87% of patients with parietal cephalocele, and only two patients (neither of whom had any other malformation) attained normal development. Brain malformations were closely related to the site from which the cephalocele issued, and dorsal cyst malformation was found in eight patients with parietal cephalocele. Two types of atretic cephaloceles were found, each in a different location. The first type was an alopecic lesion occurring in the parietal midline; all five patients with this type had dorsal cyst malformations and none developed normally. The second type was a nodular lesion developing at the occipital midline, not associated with cerebral anomalies; all five patients with this type showed normal development. The pathogenesis of atretic cephaloceles and their associated intracranial malformations are discussed.

Migration of a dissected peritoneal shunt catheter into the scrotum.

Migration of a dissected peritoneal piece of the shunting material into the scrotum was encountered in a 1-year-old boy who had received a V-P shunt. Removal of the migrated shunt tube by inguinal exploration and herniorrhaphy were performed, and another V-P shunt was installed simultaneously. This case was considered worthy of reporting as a rare complication of a V-P shunt, and the causal mechanism is discussed with a review of the literature.

Cerebellar porencephaly in an adult--case report.

A 51-year-old female presented with an extremely unusual cerebellar porencephalic lesion manifesting as progressive cerebellar signs and cranial nerve pareses. T1-weighted magnetic resonance imaging demonstrated a low-signal-intensity area in the left cerebellar hemisphere suggesting a cavity communicating with the fourth ventricle. Histological study showed the wall of the cavity contained nonspecific gliosis. A diagnosis of porencephaly was made.

Enhanced secretion of endothelin by endothelial cells in response to hemoglobin.

Confluent cultures of bovine aortic endothelium in serum-free medium were exposed to increasing concentrations (10(-6)-10(-4) M) of freshly prepared erythrocyte lysates (primarily hemoglobin). Hemoglobin increased endothelin-1 secretion into the medium in a dose-dependent manner after 24 hours. The enhanced secretion of endothelin-1 in response to hemoglobin was sustained for 72 hours, suggesting active production and secretion of endothelin-1 rather than release from intracellular pools. Secreted endothelin-1 in the medium was characterized by high-performance liquid chromatography coupled with radioimmunoassay. Endothelin-1, a potent and long-lasting vasoconstrictor, may be one of the causative factors of cerebral vasospasm after subarachnoid hemorrhage. Oxyhemoglobin, derived from periarterial clot, may play an important role in the secretion of endothelin-1 in cerebral vasospasm.

[Recurrence of AVM after disappearing on postoperative angiography--report of two cases].

We reported two cases of recurrent arteriovenous malformation (AVM), which had been operated on before and these AVMs disappeared on postoperative angiography. The first case was a 13-year-old boy who had suffered from intracerebral hematoma at the age of nine years. The first angiography showed AVM located in the left central region, fed by peripheral branches of the anterior and middle cerebral arteries. Sixteen days after the onset, removal of the AVM was carried out. Postoperative course was uneventful and angiography showed that the AVM had disappeared. However, 4 years later, follow-up digital subtraction angiography showed that the AVM had reappeared in the operated region. Extirpation of the recurrent AVM was repeated. The second case was a 28-year-old woman who had presented intracerebral hematoma at the age of 23 years. Angiography revealed AVM located in the right posterotemporal region, fed by a temporal branch of the middle cerebral artery. Removal of the AVM was carried out one month after the onset. Postoperative neurological status was good and angiography showed no residual AVM. Five years later, enhanced CT scan demonstrated a linear enhanced area in the operated region. This led us to suspect recurrence of the AVM. Conventional angiography presented reappearance of the AVM, and reoperation was performed. Reported cases of AVM, which recurred after disappearing on postoperative angiography, were very rare. Small abnormal vascular channels located in the surrounding area of the main nidus may be left after the initial operation, and they may have grown to nidus some years later.(ABSTRACT TRUNCATED AT 250 WORDS)

A pediatric case of carotid rete mirabile.

BACKGROUND: Carotid rete mirabile (CRM) is a physiological network between the external carotid and internal carotid systems in lower mammals. Very rarely, these arterial channels are observed in humans. CASE DESCRIPTION: We describe a 13-year-old girl with CRM who presented with acute hemiplegia after an operation for Dieulafoy's ulcer, a submucosal vascular anomaly of the stomach. Angiogram revealed hypoplasia of the bilateral internal carotid arteries. The abnormal network from the external carotid system was seen around the cavernous portion of the internal carotid arteries. The ophthalmic arteries were developed as the collateral pathway. CONCLUSIONS: To our knowledge, this is the first pediatric case reported in the literature. CRM sometimes accompanies intracranial or systemic vascular disorders such as cerebral aneurysm and pseudoxanthoma elasticum. CRM is a unique pathological condition that presents as a hemorrhagic or ischemic cerebrovascular disorder.

Enlargement of a cerebral aneurysm associated with ruptured arteriovenous malformation.

Enlargement of a small aneurysm during an eleven year period was encountered in a 32-year-old man who had experienced intracranial haemorrhage from a distally located AVM. Clipping of the feeding artery together with the aneurysmal neck was performed. It was very rare to observe the aneurysmal growth associated with the AVM. This case was considered worth reporting as supporting evidence that hemodynamic stress plays an important role in the development of an aneurysm.

Initial and postoperative hyponatremia associated with pituitary adenoma: a case report.

This 67 year-old man experienced 3 episodes of symptomatic hyponatraemia. Radiological examination revealed a sellar lesion and the tumour was removed via the transsphenoidal route. Thereafter, he simultaneously developed intractable diabetes insipidus and serious hyponatraemia with persistent natriuresis. His level of atrial natriuretic peptide was not significantly elevated, however, his plasma aldosterone concentration was low. The oral administration of salt gradually improved his hyponatraemia as well as the coincident symptoms. By the administration of a mineralocorticoid, fludrocortisone acetate, we succeeded in maintaining his serum sodium level without salt replacement. We discuss the mechanism(s) and treatment of hyponatraemia associated with pituitary tumour.

[Regional cerebral blood flow measurement in brain tumors].

The regional cerebral blood flow (CBF) was determined on seventeen patients with brain tumors. Ring type single photon emission CT (SPECT) was used following intravenous injection of 133Xe. Case materials included eleven meningiomas and six malignant gliomas. Evaluation was performed with emphasis on the following points; Correlation of the flow data within tumors to the angiographic tumor stains, Influence of tumors on the cerebral blood flow of the normal brain tissue, Correlation between degree of peripheral edema and the flow data of the affected hemispheres. There was significant correlation between flow data within tumors and angiographic tumor stains in meningiomas. Influence of tumors on cerebral blood flow of the normal tissue was greater in meningiomas than in gliomas. There was negative correlation between the degree of peripheral edema and the flow data of the affected hemisphere. It has been concluded that the measurement of CBF in brain tumors is a valuable method in evaluation of brain tumors.

Carotid rete mirabile presenting subarachnoid haemorrhage. Report Of two cases.

Carotid rete mirabile (CRM) consists of arterial channels between the internal and external carotid arteries in some lower mammals. It is a very rare pathological condition in humans. We report two patients who presented with clinical signs of subarachnoid haemorrhage (SAH). Their sudden-onset SAH was thought to have been due to rupture of cerebral aneurysms, however, angiograms revealed an abnormal vascular network around the cavernous sinus. To our knowledge, 2 of 7 reported patients with CRM presented with SAH, however, only one of these patients had a probable cerebral aneurysm. We suggest that in patients with CRM, the rupture of anastomosing vessels be a probable cause of SAH.