Aneurysms of the distal anterior inferior cerebellar artery (AICA) are rare; fewer than 100 cases have been reported. The authors detail their experience with four cases and present endovascular as well as microsurgical management options. The medical records and neuroimaging studies obtained in four patients who were treated at a single institution were reviewed. Clinical presentations, neuroimaging and intraoperative findings, and clinical outcomes were analyzed. There were three men and one woman; their mean age was 43 years. Two patients presented with acute subarachnoid hemorrhage (SAH), and two presented with ataxia and vertigo (one with tinnitus, the other with hearing loss). Angiographic studies demonstrated aneurysms of the distal segment of the AICA. In one patient with von Hippel-Lindau syndrome and multiple cerebellar hemangioblastomas, a feeding artery aneurysm was found on a distal branch of the AICA. Three of the patients underwent successful surgical obliteration of their aneurysms, one by clipping, one by trapping, and one by resection along with the tumor. The fourth patient underwent coil embolization of the distal AICA and the aneurysm. All patients made an excellent neurological recovery. Patients with aneurysms in this location may present with typical features of an acute SAH or with symptoms referable to the cerebellopontine angle. Evaluation with computerized tomography, magnetic resonance (MR) imaging, MR angiography, and digital subtraction angiography should be performed. For lesions distal to branches coursing to the brainstem, trapping and aneurysm resection are viable options that do not require bypass. Endovascular obliteration is also a reasonable option, although the possibility of retrograde thrombosis of the AICA is a concern.

Sinus histiocytosis with massive lymphadenopathy was first described in 1969 by Rosai and Dorfman. The typical clinical characteristics of this disease include painless cervical lymphadenopathy, fever, and weight loss. The condition can present with an extranodal mass in about 25% of patients, and isolated masses without lymph node involvement occur rarely. The authors describe a 5-year-old boy with cavernous sinus syndrome due to an isolated extranodal form of sinus histiocytosis with massive lymphadenopathy in the temporal fossa. Several cases of this disease involving the central nervous system are reviewed. The histopathological and magnetic resonance imaging characteristics are discussed.

Traumatic acute subdural hematoma is associated with high mortality in the pediatric population, yet the pathophysiology remains poorly understood. The objective of this study was to develop a pediatric model of acute subdural hematoma, and to evaluate the resultant histopathological changes in the brain. Ten 3-week-old piglets were studied. A 5-mm craniotomy was made in the right frontal skull. A small silastic tube was inserted through the underlying intact dura into the subdural space. A craniotomy was made posterior to the right coronal suture with underlying dura left intact (closed cranial window model). Injection of 5 ml autologous, nonheparinized blood was accomplished through the silastic tube. Animals were sacrificed after 72 h or 1 week. During the subdural injection, intracranial pressure rose to 62 ± 8 mm Hg, and returned to baseline within 1 h of surgery. Mean arterial blood pressure increased transiently. Cresyl violet and hematoxylin and eosin staining demonstrated extensive areas of white matter necrosis under the hematoma after 72 h survival (n = 7). Zones of necrosis were also noted in cortex, but were less extensive than those seen in white matter. These results differ from adult rodent models in which cortex is primarily affected. This is the first reported pediatric model of traumatic acute subdural hematoma. This model can be used in future studies to investigate pharmacological or other therapies which may improve outcome after this type of injury.

The seizure outcome and neurological outcome in children who undergo reoperation for failed epilepsy surgery have not been well documented. This retrospective study evaluated 20 children who underwent a second resective surgery for recurrent seizures. Four categories of patients were identified: (1) extension of the initial resection was performed in 8 patients; (2) 5 patients underwent lobectomy or corticectomy in a region remote from the original surgical site; (3) multilobar resection which may have included further resection of the initial procedure was accomplished in 4 patients; (4) hemispherectomy was performed in 3 patients. Patients with reoperation in the same lobe as the first procedure (group 1) had a 62% seizure-free rate, while 44% of patients in groups 2 and 3 were free from seizures at follow-up evaluation. Patients undergoing hemispherectomy had a 67% seizure-free rate. Significant unexpected neurological deficits occurred in 3 patients who underwent multilobar resection at reoperation. Complications included motor and language deficits. Reoperation for intractable partial epilepsy is beneficial in selected children. Patients who require multilobar resections may have higher risk of postoperative neurological deficit than those patients with reoperation in one lobe. These factors may be useful in counseling parents of children considering reoperation for recurrent epilepsy.

Cellular stress, which leads to increases in the phosphorylation of HSP27, inhibits cyclic nucleotide-dependent vascular relaxation and cyclic nucleotide-dependent increases in the phosphorylation of HSP20.