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A 29-year-old woman had a 2-month history of an enlarging lesion over her left frontal bone following minor trauma. CT scan showed an osteolytic lesion with an overlying soft tissue mass, thought to be an unhealed skull fracture with pseudomeningocele. Left frontal craniotomy revealed a soft tissue mass, which was resected. Histologic examination revealed multinucleated giant cells mixed with Langerhan's cells that showed the characteristic 'coffee bean nuclei.' Eosinophils were scant. Immunostaining for CD1a and S100 revealed strong positive staining primarily in the Langerhans' cells while giant cells and inflammatory cells were negative. Immunostaining for CD68, in contrast, stained the osteoclast-like giant cells and macrophages. Electron microscopy confirmed the presence Birbeck granules. The final diagnosis was Langerhans' cell histiocytosis (histiocytosis X) of the skull

The literature on spinal vascular malformations contains a great deal of confusing terminology. Some of the nomenclature is inconsistent with the lesions described. Based on the experience of the senior author (R.F.S.) in the treatment of more than 130 spinal cord vascular lesions and based on a thorough review of the relevant literature, the authors propose a modified classification system for spinal cord vascular lesions. Lesions are divided into three primary or broad categories: neoplasms, aneurysms, and arteriovenous lesions. Neoplastic vascular lesions include hemangioblastomas and cavernous malformations, both of which occur sporadically and familially. The second category consists of spinal aneurysms, which are rare. The third category, spinal cord arteriovenous lesions, is divided into arteriovenous fistulas and arteriovenous malformations (AVMs). Arteriovenous fistulas are subdivided into those that are extradural and those that are intradural, with intradural lesions categorized as either dorsal or ventral. Arteriovenous malformations are subdivided into extradural-intradural and intradural malformations. Intradural lesions are further divided into intramedullary, intramedullary-extramedullary, and conus medullaris, a new category of AVM. This modified classification system for vascular lesions of the spinal cord, based on pathophysiology, neuroimaging features, intraoperative observations, and neuroanatomy, offers several advantages. First, it includes all surgical vascular lesions that affect the spinal cord. Second, it guides treatment by classifying lesions based on location and pathophysiology. Finally, it eliminates the confusion produced by the multitude of unrelated nomenclatural terms found in the literature

The treatment of arteriovenous malformations (AVMs) has evolved over the last 40 years. These complex vascular lesions remain among the most difficult lesions to treat. Successful treatment of AVMs of the brain includes extensive preoperative planning, multimodality treatment options, and modern postoperative surgical care. The advent of new technologies, including interventional neuroradiology and radiosurgery, has expanded the range of malformations that can be treated effectively and has had a significant impact on those individuals who manifest this disease process. The purpose of this paper is to describe the current grading technique used by the authors and to explore the preoperative treatment and planning that leads to successful surgical obliteration of these lesions. Some description of preoperative interventions, including radiosurgery and interventional procedures will be mentioned; however, only in the context of how they impact on the surgical treatment of these lesions. In other articles in this edition of Neurosurgical Focus interventional procedures and radiosurgery as treatment adjuncts and as primary therapies will be discussed in greater detail

Gamma knife radiosurgery is generally considered a safer alternative to traditional pallidotomy or thalamotomy. We report the case of a 59-year-old patient with essential tremor who developed a complex, disabling movement disorder following gamma knife thalamotomy. This case illustrates the need for long-term follow-up to fully evaluate the potential for complications following radiosurgery

The treatment of essential tremor with thalamic deep brain stimulation (DBS) is considered to be more effective and to cause less morbidity than treatment with thalamotomy. Nonetheless, implantation of an indwelling electrode, connectors, and a generator is associated with specific types of morbidity. The authors describe three patients who required revision of their DBS systems due to lead breakage. The connector between the DBS electrode and the extension wire, which connects to the subclavicular pulse generator, was originally placed subcutaneously in the cervical region to decrease the risk of erosion through the scalp and to improve cosmesis. Three patients presented with fractured DBS electrodes that were located in the cervical region near the connector, necessitating reoperation with stereotactic retargeting and placement of a new intracranial electrode. At reoperation, the connectors were placed subgaleally over the parietal region. Management of these cases has led to modifications in the operative procedure designed to improve the durability of DBS systems. The authors recommend that surgeons avoid placing the connection between the DBS electrode and the extension wire in the cervical region because patient movement can cause microfractures in the electrode. Such microfractures require intracranial revision, which may be associated with a higher risk of morbidity than the initial operation. The authors also recommend considering prophylactic relocation of the connectors from the cervical area to the subgaleal parietal region to decrease the risk of future DBS electrode fracture, which would necessitate a more lengthy procedure to revise the intracranial electrode

The endovascular management of cerebral aneurysms is undergoing revolutionary growth. Recent advances in endovascular surgery including balloon remodeling, revascularization techniques, functional cerebral rearrangement, intracranial stents, treatment for vasospasm and coil design are discussed, as are their future considerations

Vasospasm following aneurysmal subarachnoid hemorrhage (SAH) is correlated with the thickness of blood within the basal cisterns on the initial computerized tomography (CT) scan. To identify additional risk factors for symptomatic vasospasm, the authors performed a prospective analysis of 75 consecutively admitted patients who were treated for aneurysmal SAH. Five patients who died before treatment or were comatose postoperatively were excluded from the study. Of the remaining 70 patients, demographic (age, gender, and race) and clinical (hypertension, diabetes, coronary artery disease, smoking, alcohol abuse, illicit drug use, sentinel headache, Fisher grade, Hunt and Hess grade, World Federation of Neurological Surgeons grade, and ruptured aneurysm location) parameters were evaluated using multivariate logistic regression to determine factors independently associated with cerebral vasospasm. All patients were treated with hypervolemic therapy and administration of nimodipine as prophylaxis for vasospasm. Cerebral vasospasm was suspected in cases that exhibited (by elevation of transcranial Doppler velocities) neurological deterioration 3 to 14 days after SAH with no other explanation and was confirmed either by clinical improvement in response to induced hypertension or by cerebral angiography. The mean age of the patients was 50 years. Sixty-three percent of the patients were women, 74% were white, 64% were cigarette smokers, and 46% were hypertensive. Ten percent of the patients suffered from alcohol abuse, 19% from sentinel bleed, and 49% had a Fisher Grade 3 SAH. Twenty-nine percent of the patients developed symptomatic vasospasm. Multivariate analysis demonstrated that cigarette smoking (p = 0.033; odds ratio 4.7, 95% confidence interval [CI] 2.4-8.9) and Fisher Grade 3, that is, thick subarachnoid clot (p = 0.008; odds ratio 5.1, 95% CI 2-13.1), were independent predictors of symptomatic vasospasm. The authors make the novel observation that cigarette smoking increases the risk of symptomatic vasospasm after aneurysmal SAH, independent of Fisher grade