Temozolomide in the treatment of an invasive prolactinoma resistant to dopamine agonists.

Prolactinomas are common tumors of the anterior pituitary gland. While conventional therapies, including dopamine agonists, transsphenoidal surgery and radiotherapy, are usually effective in controlling tumor growth, some patients develop treatment-resistant tumors. In this report, we describe a patient with an invasive prolactinoma resistant to conventional therapy that responded to the administration of the alkylating agent, temozolomide.

Targeting the cranial nerve: microradiosurgery for trigeminal neuralgia with CISS and 3D-flash MR imaging sequences.

Object: The authors undertook a study to identify magnetic resonance (MR) imaging techniques that can be used reliably during gamma knife surgery (GKS) to identify the trigeminal nerve, surrounding vasculature, and areas of compression.

Methods: Preoperative visualization of the trigeminal nerve and surrounding vasculature as well as targeting the area of vascular compression may increase the effectiveness of GKS for trigeminal neuralgia. During the past years our gamma knife centers have researched different MR imaging sequences with regard to their ability to visualize cranial nerves and vascular structures.

Determination of the 4 mm Gamma Knife helmet relative output factor using a variety of detectors.

Though the 4 mm Gamma Knife helmet is used routinely, there is disagreement in the Gamma Knife users community on the value of the 4 mm helmet relative output factor. A range of relative output factors is used, and this variation may impair observations of dose response and optimization of prescribed dose. To study this variation, measurements were performed using the following radiation detectors: silicon diode, diamond detector, radiographic film, radiochromic film, and TLD cubes.

Endoscopic sphenoidotomy approach to the sella.

Objective: Advances in optics, miniaturization, and endoscopic instrumentation have revolutionized surgery in the past decade. We report our experience with the endoscope in nine patients with sellar lesions who underwent an endoscopic sphenoidotomy approach to the sella.

Methods: An endoscopic transnasal cavity sphenoidotomy approach without a septal dissection was used in the resection of pituitary adenomas and other sellar lesions.

A proposed classification for spinal and cranial dural arteriovenous fistulous malformations and implications for treatment.

A classification is proposed that unifies and organizes spinal and cranial dural arteriovenous fistulous malformations (AVFMs) into three types based upon their anatomical similarities. Type I dural AVFMs drain directly into dural venous sinuses or meningeal veins. Type II malformations drain into dural sinuses or meningeal veins but also have retrograde drainage into subarachnoid veins.

Respiratory dysfunction associated with traumatic injury to the central nervous system.

Pulmonary dysfunction is a common complication of head trauma and spinal cord injury. Abnormal breathing patterns reflect the influence of altered neural integration. Early arterial hypoxemia can result from ventilation-perfusion mismatching, microatelectasis, aspiration, fat embolism, or the development of the adult respiratory distress syndrome.

Enlargement of basilar artery aneurysms following balloon occlusion--"water-hammer effect". Report of two cases.

Two patients with distal basilar aneurysms were treated with intra-aneurysmal balloon occlusion. After apparently successful therapy, follow-up angiograms demonstrated aneurysm enlargement with balloon migration distally in the sac. Geometric mismatch between the base of the balloons and the aneurysm neck together with transmitted pulsation through the 2-hydroxyl-ethylmethacrylate (HEMA)-filled balloon directly contributed to aneurysm enlargement.

De novo development of an aneurysm: case report.

A case of the de novo formation of an aneurysm in a young woman is presented. At age 13 years, she had a spontaneous subarachnoid hemorrhage. Cerebral angiography showed an aneurysm of the bifurcation of the left internal carotid artery and a small aneurysm of the left anterior choroidal artery.

Temporary balloon occlusion of a proximal vessel as an aid to clipping aneurysms of the basilar and paraclinoid internal carotid arteries: technical note.

One aneurysm of the basilar artery and three large, paraclinoid aneurysms of the internal carotid artery (ICA) were treated with the aid of intraoperative temporary balloon occlusion of the vessel. Optimal clip placement was confirmed using intraoperative angiography. This technique provided excellent proximal vascular control and for the large aneurysms of the paraclinoid ICA obviated the need for surgical exposure of the ICA in the neck.

Hyponatremia in neurosurgical patients.

Hyponatremia is the most common electrolyte disturbance seen in a neurosurgical ICU. The most common cause is impaired excretion of water, which may be due to many causes. The hyponatremia itself is of importance only because of its effect on ECF osmolality, which, when low, causes cellular swelling and dysfunction.

Intradural spinal lipomas.

Intradural spinal lipomas are rare, and their origin is unknown. Although the clinical presentation may not be distinctive, the neuroradiographic presentation is. Total excision is usually not possible, although subtotal resection is easily accomplished using an ultrasonic aspirator.

Delayed chiasmal decompression after transsphenoidal operation for a pituitary adenoma.

A patient with a large pituitary adenoma and visual field loss showed no significant change 6 weeks after transsphenoidal operation, but marked and abrupt improvement occurred at 10 weeks. The implications of this delayed improvement are discussed.

The isolation and characterization of Ca++-accumulating subcellular membrane fractions from cerebral arteries.

A study was undertaken using differential centrifugation methods to isolate from rabbit cerebral arteries the subcellular microsomal protein fractions capable of actively sequestering Ca++. One isolated protein fraction displayed a relatively large adenosine triphosphate (ATP)-dependent Ca++-accumulating capacity that was completely inhibited by NaN3, and was therefore designated the "mitochondrial fraction." Electron microscopy confirmed that this fraction consisted of numerous mitochondrial elements.

Preoperative arteriographic spasm and outcome from aneurysm operation.

The timing of intracranial operation for the treatment of ruptured cerebral aneurysm remains controversial. To find objective parameters to guide us, we performed angiography 24 to 72 hours before contemplated operation in 35 Grade I patients in whom subarachnoid hemorrhage had occurred at least 1 week earlier. Operation in the presence of angiographic vasospasm in Grade I patients over 1 week after SAH was associated with increased morbidity and mortality rates.

Epsilon-aminocaproic acid and recurrent subarachnoid hemorrhage: a clinical trial.

A clinical trial of epsilon-aminocaproic acid (EACA) in preventing recurrent hemorrhage from intracranial arterial aneurysms is reported. Previous reports were reviewed, and their results concerning antifibrinolytic agents were inconclusive in establishing their efficacy. One hundred patients with documented ruptured intracranial aneurysms were admitted to this study within 48 hours of the initial hemorrhage: 45 patients received 36 gm of EACA/day, with 11 documented rebleeds and one suspected rebleed.

Lateral approach to the upper cervical spine.

A procedure for access to the ventral portion of the spinal canal from the foramen magnum to the superior portion of C-3 is described. This is useful for lesions that are primarily ventral or ventrolateral to the spinal cord, such as meningiomas or neurofibromas. The exposure involves no more bone removal than does a posterior laminectomy, but the angle of approach reduces markedly the amount of spinal cord manipulation necessary to deal with ventrally situated lesions.

Implications of very high serum prolactin levels associated with pituitary tumors.

Five patients with pituitary tumors associated with unusually high serum prolactin levels are presented. Tumor size and the presence of suprasellar extension were variable, but the finding common to all five cases was invasion of the cavernous sinus. It is proposed that very high serum prolactin levels suggest an invasive tumor, perhaphs, specifically, invasion into a cavernous sinus.

Lipoma of the corpus callosum.

A case of corpus callosum lipoma with presumptive diagnosis is presented. Review of the literature disclosed 84 cases with such diagnoses. Lipoma of the corpus callosum is a rare intracranial lesion, perhaps congenital and often asymptomatic, but can present with seizure disorder, headache, mental changes, paresis or paralysis.

Listeria monocytogenes: brain abscess or meningoencephalitis?

A brain abscess caused by Listeria monocytogenes developed in an immunosuppressed renal transplant patient. Meningitis and meningoencephalitis from this organism were encountered in three other renal transplant recipients at this medical center during the past 4 years. Focal neurologic deficits occurred in patients with either Listeria abscess or meningoencephalitis.