Thomas G. Luerssen

Arachnoid Cyst Rupture with Concurrent Subdural Hygroma

Arachnoid cysts (ACs) are relatively common intracranial mass lesions, which occur most often in the middle cranial fossa. While these lesions can present as a mass lesion, many are asymptomatic. Rarely, posttraumatic or spontaneous rupture of ACs can result in intracystic hemorrhage, subdural hematoma or subdural hygroma. We have encountered two cases of ruptured arachnoid cysts that resulted in subdural hygromas. Both patients harbored middle cranial fossa cysts and suffered mild closed head injuries. The presentation, radiographic findings and surgical management of these patients as well as the association between ACs and subdural hygromas are described.

Phase II Study of High-Dose Chemotherapy Before Radiation in Children with Newly Diagnosed High- Grade Astrocytoma Final Analysis of Children's Cancer Group Study 9933

High‐grade astrocytomas (HGA) carry a dismal prognosis and compose nearly 20% of all childhood brain tumors. The role of high‐dose chemotherapy (HDCT) in the treatment of HGA remains unclear.

Cerebrospinal Fluid Vasopressin and Vasotocin in Health and Disease

It is now recognized that integrative central nervous system function involves not only electrophysiological phenomena and chemical neurotransmission, but also interaction between brain and endocrine hormones. With the recent upsurge in interest in “peptidergic” neurons, it has become evident that many hypothalamic and pituitary peptides occur in brain outside the boundaries of the hypothalamo-pituitary axis. Anterior and posterior pituitary peptides, hitherto characterized as “peripheral hormones,” have now been identified in cerebrospinal fluid (CSF). This Chapter reviews our current knowledge about the occurrence of the antidiuretic hormone, arginine vasopressin (AVP), and the closely related nonapeptide hormone, arginine vasotocin (AVT), in human CSF.

Intracranial pressure: Current status in monitoring and management

One of the most frequently occurring questions in the neurological critical care of children involves the indications for measurement of intracranial pressure (ICP) and the appropriate therapies for abnormally elevated ICP. Advances in monitoring technology have improved the safety and accuracy of ICP measurement. Clinical and basic research into the mechanisms of brain swelling and the efficacy of various therapies, especially in the realm of traumatic brain injury, has allowed the development of rational and specific treatment strategies for elevated ICP. For several diseases, the ability to measure and manage ICP has resulted in marked improvements in outcomes. This article reviews the indications for, and recommended methods of, measuring ICP in children and discusses the status of therapies commonly used to control elevated ICP.

SHUNT INFECTION AND MALFUNCTION AFTER AUGMENTATION CYSTOPLASTY

PURPOSEnMaintenance of a sterile intraperitoneal environment is critical in patients with ventriculoperitoneal shunts. Recent series have reported a broad discrepancy in the rate of shunt infection (0% to 20%) following augmentation cystoplasty. The need for distal shunt revision has not been well defined. We report the incidence of shunt infection and revision at our institution after bladder augmentation.nnnMATERIALS AND METHODSnWe retrospectively reviewed the records of all patients with myelodysplasia and a ventriculoperitoneal shunt who underwent augmentation cystoplasty since August 1990. All patients included in the study had a minimum of 12 months of followup.nnnRESULTSnA total of 55 patients with a ventriculoperitoneal shunt secondary to myelodysplasia required augmentation cystoplasty for management of a neuropathic bladder. Standard perioperative intravenous and oral antibiotic preparation, mechanical bowel preparation and intraoperative shunt isolation were used. Mean postoperative followup was 60.4 months (range 12 to 111). One patient presented with an extruded peritoneal shunt tip and positive cultures from cerebrospinal fluid and urine. Bladder perforation occurred in 2 patients and the shunt was empirically externalized. Revision was required for 5 (9%) distal shunt obstructions, including 1 cerebrospinal fluid pseudocyst.nnnCONCLUSIONSnThe incidence of shunt infection after augmentation cystoplasty is low (less than 2% in this large series), and presence of a ventriculoperitoneal shunt should not preclude bladder augmentation. Meticulous perioperative and intraoperative preparation contributes to the low rate of adverse events. Although the rate of distal revision after augmentation is significant, it does not exceed the reported distal failure rate for ventriculoperitoneal shunts in children without a history of urological surgery.

Brainstem gliomas of childhood Magnetic resonance imaging

We compared magnetic resonance imaging (MRI) and CT on 16 children with brainstem gliomas. MRI demonstrated masses of decreased signal intensity, which enlarged and distorted brainstems in all patients with active disease and showed brainstem abnormalities in 21 of 23 studies (91%). In one-half of the patients, MRI showed more extensive disease than did CT. Exophytic portions of tumors were shown well on MRI. MRI was more sensitive than CT in demonstrating disease relapse.

CLOACAL EXSTROPHY: THE NEUROLOGICAL IMPLICATIONS

Congenital anomalies commonly accompany the abdominal wall defects of cloacal exstrophy with an incidence as high as 100% in some series. The urological literature cites an incidence of vertebral and/or spinal cord anomalies in 75% of cases. We reviewed the records of the 17 patients with cloacal exstrophy treated at our institution since 1978. Abnormalities of the vertebral column or spinal cord were identified in 16 patients, including 11 of 12 (92%) fully evaluated by myelography, computerized tomography or magnetic resonance imaging of the lumbosacral spinal cord. Nine patients had a lipomeningocele and 4 had a lipomyelocystocele. Spinal exploration, repair and cord untethering were done in 11 patients of whom 2 subsequently underwent reoperation for re-tethering the cord. A total of 15 patients is ambulatory although 5 require lower extremity braces. The incidence of spinal cord or vertebral anomalies in our patients with cloacal exstrophy approaches 100%, which is higher than commonly cited in the urological literature. We recommend magnetic resonance imaging of the spinal cord as part of the initial evaluation of newborns with cloacal exstrophy. Lifelong attention to the risk of spinal cord tethering can optimize neurological outcome in affected individuals.

Spontaneous saphenous neuralgia.

Six patients representing seven cases of spontaneous (nontraumatic) saphenous neuralgia secondary to entrapment of the nerve in the subsartorial canal are presented. All patients complained of medial knee and leg pain. Clinical findings included tenderness over the subsartorial canal and sensory changes in the cutaneous distribution of one or both terminal branches of the saphenous nerve. The diagnosis was confirmed by saphenous nerve block in all cases. All patients were treated operatively, which resulted in symptomatic improvement. All six patients initially underwent external neurolysis; however, three patients required saphenous neurectomy for recurrent symptoms. Saphenous neuralgia should be considered in the differential diagnosis of medial lower extremity pain.

Chiari III malformation treated with CSF diversion and delayed surgical closure

Chiari III malformations are extremely rare hindbrain malformations that are associated with a high early mortality rate, or severe neurologic deficits in the survivors. The preferred treatment is early operative closure and CSF shunting. We report a case of a newborn infant with a Chiari III malformation with displacement of the brainstem and cerebellum into the cervical encephalocele which precluded immediate operative closure of the defect. Instead, a ventriculoperitoneal shunt was placed and the patient was followed with serial imaging studies. The child survived. The shunt allowed the brainstem and cerebellum to regress into the cervical spinal canal as the dilated cerebral aqueduct and fourth ventricle decompressed. A delayed closure of the cervical encephalocele was performed at 30 months of age. Cerebrospinal fluid diversion with delayed closure may be an option for large lesions.

Magnetic resonance imaging diagnosis of a cerebral aneurysm in an infant.

A posterior cerebral artery aneurysm presented as a seizure disorder in a 7-week-old infant. A small hemorrhage in the posterior thalamus was seen on CT scan. However, magnetic resonance imaging (MRI