Showing papers in "Neurosurgery in 1983"

Posterior-lateral foraminotomy as an exclusive operative technique for cervical radiculopathy: a review of 846 consecutively operated cases.

Abstract: Between 1963 and 1980, one or more posterior-lateral foraminotomies were performed for simple cervical radiculopathy as the sole operative procedure for 736 patients. One hundred three patients (14%) required a second posterior procedure, but only 24 (3%) cases represented true recurrent radiculopathy. There were 13 minor complications (1.5%) and no deaths or detectable incidence of air embolism. All operations were done with the patient in the sitting position. Central venous pressure monitoring was used only infrequently. There was a 96% incidence of relief of significant arm pain and/or paresthesia and a 98% incidence of resolution of preoperatively present motor deficit. Eight hundred twenty-eight procedures (98%) were preceded by Pantopaque cervical myelography. There was a 71.5% incidence of correlation between preoperative clinical findings (both sensory and motor) and operative findings. In 13% of the cases, two spaces were thought by the operating surgeon to be equally involved by the spondylotic process. Most (91.5%) of the patients describe themselves as either "good or excellent" postoperatively. There was no significant difference postoperatively regarding results or recurrence between patients with suspected soft or hard disc protrusions and those with strictly spondylotic radiculopathy. Nor was there any statistical difference in results among the three patient population groups ("private" vs. compensation vs. liability). The mean length of time to return to work or other "normal" activities was 9.4 weeks. The mean length of follow-up time was 146 weeks (2.8 years). There was an associated incidence of significant lumbar disc and/or foraminal disease requiring operation of 33.4%.

Aneurysmal rebleeding: a preliminary report from the Cooperative Aneurysm Study.

Abstract: It is generally considered that the peak incidence of rebleeding after aneurysmal subarachnoid hemorrhage is at the end of the 1st or the beginning of the 2nd week after the initial rupture. However, in a series of 2265 patients admitted within 3 days of their first subarachnoid hemorrhage, the peak of rebleeding occurred on the same day as the initial hemorrhage and there was no later peak. These data suggest that new management strategies for minimizing rebleeding must be considered for patients admitted soon after aneurysm rupture.

Neuropsychological sequelae of minor head injury.

Abstract: Seventy-one patients with minor head injury were given extensive neuropsychological evaluations 3 months after injury. A significant percentage of the patients demonstrated cognitive impairment, which seemed essentially unrelated to the length of unconsciousness or of posttraumatic amnesia. Impaired patients evidenced memory and visuospatial deficits. Cognitively impaired patients also had difficulty returning to work after injury. The psychological and cognitive impairment that follows minor head injury is discussed in relation to diagnostic and intervention issues.

Chiari malformation presenting in adults: a surgical experience in 127 cases.

Abstract: We reviewed 127 patients who were operated upon for adult presentation Chiari malformation and made six conclusions: (a) The clinical examination remains crucial in the diagnosis. (b) The surgical anatomy is highly varied. (c) Syrinxes can be missed on preoperative contrast studies. (d) By a conservative grading system, we determined that 46% of the patients improved during long term follow-up. One-quarter deteriorated over the long run in spite of any treatment. (e) The overall results did not differ whether the treatment was plugging of the central canal plus decompression or decompression alone. (f) In patients with progression, plugging of the central canal obtained superior results. A review of the literature shows that the natural history of this complex disease process has not been established. This history is needed to identify the course of what may be several important factors that lead to the pathological condition in this disease.

Computed tomographic guidance stereotaxis in the management of intracranial mass lesions.

Abstract: A prototype Brown-Roberts-Welles stereotactic instrument has been used as both a diagnostic and a therapeutic surgical adjunct in cases of intracranial mass lesions. Eighty-three procedures (142 point placements) required computerized guidance stereotaxy. The unit accomplished point intracranial access with an accuracy of greater than 1 mm. Pathological processes included a variety of neoplasms (56 cases), strokes (7 cases), and infections (20 cases) affecting deep regions of the cerebral hemispheres, the ventricular system, the cerebellum, and the rostral brain stem. Procedures were undertaken with the patient under local anesthesia for biopsy (300 point specimens), culture, evacuation, aspiration, endoscopic excision, and implantation of radioisotopes. The techniques and instrumentation for each of these procedures are described. Procedural objectives were satisfactorily accomplished with no mortality and an overall complication rate of 4%. Recovery of tissue specific to establish a histological diagnosis or the etiological factors related to each disease process was realized in 94% of the cases. These results were obtained with scanner utilization times averaging 15 minutes and procedurally related patient recovery periods of less than 4 hours. The value and adaptability of the instrumentation and techniques are illustrated, and potential future applications are discussed.

Large and giant paraclinoid aneurysms: surgical techniques, complications, and results.

Abstract: Twenty-five patients with giant (greater than 25 mm in diameter) and 9 patients with large (15 to 25 mm in diameter) aneurysms of the internal carotid artery in the ophthalmic or paraophthalmic region are reviewed. In 23 of these patients the aneurysm was clipped directly. There was 1 death in this group, and none of the survivors had disabling neurological complications outside the visual system. The other 11 patients were treated by a trapping procedure or by either common carotid ligation or internal carotid ligation in the neck. Of the 5 patients treated by internal carotid ligation preceded by an extracranial to intracranial bypass graft, 3 developed embolic complications, which in 1 patient resulted in death. One of the 4 patients treated by ligation of the common carotid artery died 1 year later from a recurrent subarachnoid hemorrhage. Of the total group, 18 patients had visual loss preoperatively as a result of aneurysmal compression; in 10 the vision was improved by operation, in 3 it was made worse, and in 2 it was unchanged. In another patient the vision continued to deteriorate slowly after common carotid occlusion, and the other 2 patients died postoperatively before vision could be assessed. The complications in the patients are described and analyzed in detail. Maneuvers found to be of value in the direct approach to these lesions are described. Of these, exposure of the internal carotid artery in the neck for temporary occlusion during clipping and thorough drilling of the anterior clinoid process and unroofing of the optic canal were particularly helpful. The literature on indirect methods of treatment by carotid occlusion with and without bypass graft is reviewed with special reference to the complications and effectiveness of each alternative. Based on this review of the literature and our experience, a treatment scheme is suggested for these aneurysms depending on their mode of presentation.

Surgical Treatment of Incidental Intracranial Aneurysms

Abstract: It is clear that more incidental aneurysms will be encountered in the future. Approximately 5% or more of the population harbors these lesions, and advancing technology can be expected to demonstrate them with increasing regularity. Multiple aneurysms will also be found in at least 18% of patients with subarachnoid hemorrhage due to aneurysms. The best estimates suggest a rate of hemorrhage approximating 1%/year for incidental aneurysms and a 0.4 to 0.65% annual mortality rate for these lesions. It has also been shown that even small aneurysms may enlarge and bleed unpredictably with the passage of time. Surgery for incidental aneurysms of the anterior circulation can be accomplished without mortality and with an operative morbidity of 6.5%. Higher morbidity occurs in surgery for aneurysms in more difficult locations as well as larger aneurysms. The increased risk of bleeding from larger aneurysms, however, may justify the increased morbidity of surgery for these lesions. Surgery for incidental aneurysms can be recommended in healthy individuals whose anesthetic risk is acceptable and for aneurysms less than 1.5 cm in diameter arising from the middle cerebral and posterior communicating arteries. Advancing age alone is not a contraindication for surgery, nor is size greater than 1.5 cm in diameter; however, the latter factor increases the operative risk. Operations to clip aneurysms of the carotid bifurcation, carotid-ophthalmic, and anterior communicating arteries may also be recommended, but these aneurysms are more difficult to approach and surgery carries a higher morbidity. Larger aneurysms, greater than 1.5 cm in diameter, in patients over 60 years of age, and in less accessible locations may not benefit from operation because surgical morbidity for these lesions is high and with advancing age the lifetime risk of rupture has decreased. For incidental aneurysms of the posterior circulation there are insufficient data to make a recommendation regarding surgery, although it is anticipated that the counsel for anterior circulation aneurysms will apply. If operative mortality and morbidity are to be maintained at acceptable levels, incidental aneurysm surgery should be the province of the accomplished aneurysm surgeon who has available to him the most modern techniques and equipment. With the clipping of incidental aneurysms, hopefully the number of patients suffering from subarachnoid hemorrhage with its high morbidity and mortality rates can be further reduced.

Three-Dimensional Reconstruction of Craniofacial Deformity Using Computed Tomography

Abstract: The computed tomographic studies obtained routinely in the examination of patients with congenital or acquired defects of the skull and facial bones can be utilized as a substrate to provide an accurate three-dimensional representation of osseous abnormalities. The total dose of x-irradiation is reduced as other means of radiological examination are eliminated. Osseous structures are faithfully reproduced. Complete inspection of the reproduced structure can be made from any viewpoint, including internal inspection.

Stereotactic radiosurgery in cases of acoustic neurinoma: further experiences.

Abstract: Fourteen patients with acoustic neurinomas varying in size from 7 to 30 mm were treated by stereotactic radiosurgery and then were followed for 4 years. The tumors of eight patients decreased 1 to 10 mm in diameter, no change was found in two, and the tumor increased slightly in three patients. Loss of the ability to enhance with contrast administration on computed tomographic scan was a common effect of the treatment. One patient in poor general condition died from intercurrent disease 6 months after radiosurgery. At postmortem examination, a large central necrosis was found. Among five patients with hearing before treatment, full preservation was demonstrated in one; in the other four, the mean impairment of speech discrimination score was 43%. One patient with total unilateral deafness regained hearing and achieved a discrimination score of 60% at 1 year after treatment. There was transient facial weakness in five patients, which was detectable only by electromyography in one. Facial hypesthesia appeared in two patients and was transitory in one of them. Thirteen of the patients are in good or excellent general condition. Stereotactic radiosurgery offers the only therapeutic alternative to open operation in the management of acoustic neurinomas. It is worth considering for every patient, but especially for poor risk patients and those with bilateral tumors.

Progressive change in cerebral blood flow during the first three weeks after subarachnoid hemorrhage

Abstract: Cerebral blood flow (CBF) was estimated from each cerebral hemisphere by the 133Xe inhalation method. Daily estimates were made during the first 3 weeks after subarachnoid hemorrhage (1265 studies in 116 patients). Some of the patients were taking adrenergic blocking drugs (propranolol and phentolamine), others were taking tranexamic acid, and the rest were taking no drugs. CBF was also studied in 67 normal subjects. The resting CBF was related inversely to age not only for normal subjects but also for patients after subarachnoid hemorrhage (SAH). The CBF fell progressively during the first 2 weeks after SAH and was abnormally low throughout the 3 weeks after hemorrhage. For any 1 day after SAH, those patients who were fully alert had the smallest reduction in CBF. The progressive changes in CBF occurred whether or not an aneurysm was present on angiograms. For aneurysms situated to one side of the midline, the changes in CBF affected both sides of the brain. The progressive decline in CBF was least in those patients who subsequently made the best clinical recovery. Arterial pCO2 seemed to influence CBF throughout the 3 weeks after SAH. During the 2nd week, CBF was especially low in SAH patients treated with tranexamic acid. The serial changes in CBF are discussed in relation to current views concerning the timing of operation for ruptured aneurysms.

Spinal extradural benign synovial or ganglion cyst: case report and review of the literature.

Abstract: A lumbar spinal extradural ganglion cyst is reported, and the world literature on spinal ganglion cysts is reviewed. The clinical presentation, findings, etiology, and pathogenesis of these lesions are discussed. (Neurosurgery 13:322-326, 1983)

Causes of Unfavorable Outcome after Early Aneurysm Operation

Abstract: In a consecutive series of 160 patients in Hunt and Hess Neurological Grades I to III who were operated upon for a ruptured supratentorial aneurysm within 3 days after the hemorrhage, 42 patients (26%) had an unfavorable outcome. Delayed ischemic cerebral dysfunction with permanent deficit accounted for the unfavorable outcome in 18 patients (43% of all unfavorable results or 11% of the total series), whereas the unfavorable outcome was due to deficit ascribed to surgical trauma in 11 patients (26% of all unfavorable results or 7% of the total series) and to the initial hemorrhage in 7 patients (17% of all unfavorable results or 4% of the total series). Impaired outflow of cerebrospinal fluid with shunt dependency occurred in 3% of the total series. Of the patients with an unfavorable outcome, 17 (40%) had had arterial hypertension before the hemorrhage. The incidence of unfavorable outcome in good grade patients (Grades I and II) was not influenced by timing of operation (Day 1, 2, or 3 after hemorrhage). The results favor the opinion that it is principally the patient's condition during the acute stage that determines the outcome. (Neurosurgery 13:629-633, 1983).

Pediatric brain stem tumors: radiographic, pathological, and clinical correlations.

Abstract: A retrospective analysis of the case histories of 21 pediatric patients (ages, 2.5 to 18 years) with a histologically proven diagnosis of brain stem glioma was performed to determine whether patterns of radiographic appearance could be correlated with pathology. Based on the computed tomographic or pneumoencephalographic appearance of the tumor at the time of clinical diagnosis, tumors were divided into four types: central intrinsic (Type I), central exophytic expansion into the 4th ventricle (Type II), eccentric exophytic expansion not involving the 4th ventricle (Type III), and both eccentric and central exophytic expansion (Type IV). Regardless of the radiographic classification, all patients except one, who harbored a well-differentiated astrocytoma in the area of the pons, had an anaplastic astrocytoma (n = 14) or a glioblastoma multiforme (n = 6). There was no appreciable difference in survival between patients with either tumor histology. The presence of a cystic component did not affect survival. High resolution computed tomographic scans, with reconstructed images of the posterior fossa, can predict the presence and location of brain stem tumors and associated cysts and probably the histological nature of the tumor.

Isodense Colloid Cysts of the Third Ventricle: A Diagnostic and Therapeutic Problem Resolved by Ventriculoscopy

Abstract: Eighteen patients with a colloid cyst of the 3rd ventricle presented to the Frenchay Hospital Neurosurgery Unit. The investigations included computed tomography (CT). Of these patients, 9 had radiographically isodense cysts that caused considerable diagnostic difficulties, being described only as an anterior 3rd ventricular space-occupying lesion and lateral ventricular dilatation in all but 2 cases. The clinical findings are described and the CT appearance is discussed. The new use of ventriculoscopy may resolve the problem rapidly; ventriculoscopy made the diagnosis in 5 cases and confirmed a CT diagnosis in 3 others. (It has also confirmed the diagnosis in 2 cases of hyperdense cysts.) Lately, it has been possible to aspirate the cyst contents endoscopically or, if the colloid is too viscous, to remove it with endoscopic rongeurs. After either of these procedures, the cyst wall can be coagulated with diathermy endoscopically. The method is described, and the advantages over other investigations and treatment are discussed.

Hemifacial Spasm: Treatment by Microsurgical Facial Nerve Decompression

Abstract: The literature on hemifacial spasm and its surgical therapy is reviewed, and the authors' experiences with 20 patients are described. Vascular cross compression of the facial nerve adjacent to the brain stem is seen in 90% of the surgical patients. Mobilizing the offending vessel will cure or signif

Cerebral edema associated with meningiomas.

Abstract: The cerebral edema, as judged by computed tomographic scan, associated with supratentorial meningiomas was assessed in 55 cases. No relationship to the occurrence or the degree of edema could be established with respect to meningioma location, histological type, tumor vascularity, cellularity, number of mitotic figures, necrosis, calcification, or cortical invasion. The larger the meningioma, the more likely the presence of and the severity of cerebral edema. The edema is a significant factor in the occurrence of clinical signs and symptoms. A biopsy of cerebral cortex and white matter underlying a transitional meningioma in a patient with associated cerebral edema demonstrated perivascular astrocytic end-feet swelling in the cortex and considerable extracellular fluid in the white matter. The ultrastructural appearance is similar to that seen with primary and metastatic brain tumors and with experimental vasogenic cerebral edema.

Cerebral gangliogliomas during childhood.

Abstract: We have reviewed our experience with gangliogliomas treated in the post-computed tomography (CT) era at the Children's Hospital of Philadelphia. Of 234 newly histologically verified neoplasms seen at our institution since 1975, 10 (4.3%) were gangliogliomas of the cerebral hemispheres. The presenting complaint was seizures in 9 of 10 patients, and in 8 the seizures were poorly controlled despite increasing doses of anticonvulsant medication. At the time of diagnosis, only 2 patients had a focal neurological deficit and none had signs or symptoms of increased intracranial pressure. Learning disability and behavioral disturbances were common in this group of children. The CT appearance of these lesions was characteristic: most appeared as a cerebrospinal fluid density area that was located peripherally and often indented the skull. There was little contrast enhancement, and a few were diagnosed initially as arachnoid or porencephalic cysts. Despite the CT appearance, all but 2 of the lesions were found to be solid at operation. In one patient, the lesion appeared as an enhancing lesion of the thalamus, and this patient died. Operation resulted in symptomatic improvement. Eight of 9 children are alive, with a follow-up of 1 to 80 months (median, 19.5 months), and are free of progressive disease. Five are seizure-free while receiving anticonvulsant therapy and an additional 3 have improved seizure control as a result of operation. Two of the 3 children with intellectual difficulties preoperatively have shown improvement on testing after operation, probably the result of improved seizure control. One patient developed a disseminating malignancy and died. It is concluded that worsening seizures in the pediatric age group should warrant CT examination and that ganglioglioma should be included in the differential diagnosis of low density areas on CT.

Experience with surgical decompression of the Arnold-Chiari malformation in young infants with myelomeningocele.

Abstract: Forty-five infants with myelomeningocele in whom hydrocephalus was absent or adequately controlled developed signs and symptoms of the Arnold-Chiari malformation before the age of 3 months. All of them underwent laminectomy and opening of the dura mater for hindbrain decompression. The clinical presentation included swallowing difficulty, apneic episodes, stridor, bronchial aspiration, arm weakness, and opisthotonos. Within 2 weeks of the initial clinical presentation, the neurological status of 14 patients (31%) deteriorated dramatically and culminated in irreversible neurological deficits. In all patients, compression of the brain stem occurred in the spinal canal. A transverse dural band constricting the dural sac at the C-1 level was noted in 41% of the patients, and a mild degree of arachnoidal adhesion was noted in 23%. The lowermost level of the cerebellar tongue or medullary kink was located at C-1 to C-4 in 28 cases and at C-5 to T-1 in 17 cases. Twenty-eight (62%) of the patients were alive and 17 (38%) had died at the last follow-up assessment. All survivors showed improvement of their overall neurological function. Twenty-four made a complete recovery. The majority of deaths were attributed to respiratory failure. Early recognition of symptoms and prompt decompressive laminectomy are essential for successful management of the Arnold-Chiari malformation in infants.

Compression Injuries of the Cervical Spine: A Biomechanical Analysis

Abstract: Three intact cadavers and 10 isolated cervical spinal columns underwent compression, with forces directed vertically, forward, or rearward. Failure modes were often different than force directions. The loads required to produce bony injury or ligamentous disruption ranged from 645 to 7439 N. Flexion and extension injuries were produced at approximately 50% of the loads required for axial compression failures. The direction of force delivery correlated only partially with the resulting pathological condition. Clinical decisions based on retrospective analysis of roentgenograms may not account for the variability of forces and the prominence of ligament injuries seen in spinal trauma. Some of the difficulties encountered in biomechanical analyses of spinal trauma are discussed.

Natural history of microprolactinomas: six-year follow-up.

Abstract: A 6-year follow-up of patients harboring microprolactinomas suggests that few patients (3 of 27) demonstrate significant growth of their tumor during this time. The major hazard for such patients who are not treated seems to be their risk for the development of premature osteoporosis in the face of sustained hyperprolactinemia. The risks of this complication may exceed the risks of early surgical intervention in selected patients. This short term risk of tumor growth (about 10%) must be weighed in the decision about therapeutic endeavors.

Cavernomas of the Brain

Abstract: Our clinical and surgical experience with 16 cases of cavernous hemangioma (cavernoma) of the brain is presented. In 50% of the cases, symptoms appeared during the 3rd decade of life. The clinical picture included seizures in 50% of the cases and a brain tumor-like syndrome in 37.5%, and 12.5% of the cases began with an intracerebral hemorrhage. In our series females predominated over males by 2:1. Computed tomographic (CT) scanning is the best procedure for the diagnosis of cavernomas. However, exact preoperative diagnosis of these lesions is infrequent because cavernomas are generally accepted to be very rare. A slightly hyperdense nodule, poorly enhanced after contrast administration, is the prominent feature on the CT scan. A small, hypodense zone surrounding the lesion and calcifications within the nodule are also found. An excellent result after operation was obtained in all cases of cavernoma located in the brain hemispheres. In deeply placed cavernomas (basal ganglia or brain stem), the surgical prognosis is doubtful, and features such as the size of the lesion and its anatomical location are important.

Successful treatment of primary central nervous system lymphomas with chemotherapy after osmotic blood-brain barrier opening

Abstract: Three patients with primary central nervous system (CNS) lymphoma have had major tumor regression with multiagent chemotherapy given in association with reversible blood-brain barrier opening used to enhance drug delivery to the tumor. In addition, in one patient barrier modification was carried out in the posterior fossa by mannitol infusion into the vertebral artery without untoward effects, an approach not heretofore accomplished. Computed tomographic (CT) studies documented that discontinuation of steroids rapidly effected an increase in the delivery of contrast agent to the tumor. CT monitoring of the degree of barrier modification showed tumor nodules and tumor size not apparent on the control scans, thereby providing additional evidence of the existence of a blood-brain barrier in CNS tumors. These studies further show that drug (contrast) delivery to the tumor, as well as to the surrounding barrier, is enhanced after reversible blood-brain barrier modification. Finally, chemotherapy administered by this approach resulted in defined, objective tumor responses in these three patients.

Seizures during the immediate postoperative period.

Abstract: Twenty-three of 538 patients undergoing elective craniotomy had a seizure within 24 hours after operation. The lesion had been located extra-axially in 15 patients and intra-axially in 8 patients. Except for 1 patient who had a parietal craniotomy for an arteriovenous malformation, all patients had a frontal or temporal exposure. Only 5 patients had a previous history of seizures. Adequate levels of anticonvulsant medication were not present in 19 of the 23 patients before operation. No major postoperative metabolic abnormalities were noted in any of the 23 patients. Thirteen of the 23 patients underwent computed tomography to evaluate the etiology of their seizures; none had a significant intracerebral or extracerebral hematoma. This review suggests that an early postoperative seizure is unlikely to be due to a postoperative hematoma or to metabolic abnormality. The most common association in this series was with inadequate anticonvulsant prophylaxis. An approach to postoperative seizure prophylaxis and management is presented.

Barbiturate Therapy in Uncontrolled Intracranial Hypertension

Abstract: From July 1978 to September 1981, 27 patients from a group of 210 patients with severe head injuries developed uncontrolled intracranial hypertension despite intensive medical and surgical management These 27 patients were considered appropriate candidates for barbiturate therapy Abnormal posturing or flaccidity was present in 70% of the patients, and 41% had bilaterally fixed pupils Twenty-five of 27 patients had mass lesions requiring operation Of the 15 patients who responded to barbiturate therapy with normalization of intracranial pressure for 24 hours, 5 died (33% mortality) Nine of the 12 patients who did not respond to the barbiturate therapy died (75% mortality) The total mortality in this group of 27 patients was 52% Of the survivors, 69% had a recovery classified as good recovery/moderate disability, and 31% were in a severe disability/vegetative state The morbidity and mortality in these patients is high, but comparisons with previous studies show that this is a selected group of severe head injuries with a high percentage of poor prognostic indicators Our experience suggests that barbiturates can be effective in lowering intracranial pressure in patients with otherwise unresponsive intracranial hypertension, and, by doing so, may decrease the mortality in a group of patients considered untreatable by the usual therapeutic modalities

Control of hypertension and prophylaxis against vasospasm in cases of subarachnoid hemorrhage: a preliminary report.

Abstract: Thirty hypertensive patients with subarachnoid hemorrhage were divided randomly into two groups. The treated group was begun on preliminary volume expansion, and control of hypertension was carried out using vasodilators and centrally acting drugs. The control group was treated in the classical manner for hypertension, with a diuretic as the foundation for therapy. The incidence of clinical vasospasm was compared to that of angiographic spasm. The incidence of preoperative vasospasm in the treated group was 20%, as compared to 60% in the untreated group (P less than 0.01). Of the treated group, 87% survived to operation, whereas only 53% of the control group survived to operation (P less than 0.01).

Preoperative embolization of intracranial meningiomas

Abstract: The operative and histopathological findings in 31 cases of intracranial meningioma after preoperative embolization with Gelfoam and/or lyophilized dura mater are reported. Removal of the tumor after embolization was facilitated in those meningiomas fed exclusively or mainly by branches of the external carotid artery (29 of 31). Large areas of tumor necrosis were never seen on histopathological examination, even when suggested by large regions of decreased density on the postembolization computed tomographic scan. Preoperative embolization of the feeding vessels arising from the external carotid artery system has proven to be a useful adjunct before the resection of intracranial meningiomas.

Effect of mannitol on increased intracranial pressure.

Abstract: We studied 61 patients with a closed head injury and increased intracranial pressure (ICP). The ICP was monitored continuously, concomitant with the administration of 20% mannitol. If the ICP remained higher than 25 mm Hg for 10 minutes or more, the patient was included in the study. Analysis of monitoring records delineated four variables that were related to the response of ICP to mannitol: (a) the level of ICP 1 hour before mannitol was administered, (b) the level of ICP when mannitol was administered, (c) the amount of mannitol that was administered immediately before the resulting changes in ICP were measured, and (d) the cumulative amount of mannitol given over the 6 hours before the most recent mannitol dosage was administered. The level of the ICP measurements and the cumulative amount of preceding doses of mannitol influenced the response of ICP to mannitol more than did the size of the dose of mannitol. These findings imply that: (a) the initial administration of more mannitol than is absolutely needed may lead to larger doses being required to control ICP and (b) for that reason, mannitol given on a gram/kilogram, an hourly, or a serum osmolarity basis to control increased ICP has negative long term effects because more mannitol may be required to decrease ICP when an excessive amount of it has been given previously.

Thoracic disc herniation: operative approaches and results.

Abstract: In a series of 12 cases of thoracic disc herniation operated upon at the University of Pittsburgh, 4 different operative approaches were used. These included laminectomy in 2 early cases, posterolateral extrapleural operation in 5 cases, transthoracic operation in 3 cases, and transpedicular operati

Postoperative intervertebral disc space infection.

Abstract: Intervertebral disc space infection is an uncommon, but serious, complication of disc surgery. By a retrospective chart review, we identified 27 patients at our institution who had a postoperative disc space infection; 14 were diagnosed and treated within the last 5 years. The characteristic symptoms were severe spinal pain and limited spinal mobility beginning 7 to 30 days postoperatively. The key physical findings were paravertebral muscle spasm and marked mechanical signs. The key laboratory findings were an elevated erythrocyte sedimentation rate and a mildly elevated white blood cell count. The diagnosis was based on the clinical presentation and early radiographic changes in the vertebral bodies adjacent to the involved disc, especially irregularities of the cortical margins seen best by tomography. Definitive bacteriological diagnosis by Craig needle biopsy was attempted in 14 patients; 7 had positive cultures and all yielded a Staphylococcus species. The usual treatment consisted of the administration of antistaphylococcal antibiotics and immobilization of the spine with a spica cast, a plastic body jacket, or complete bedrest. The final radiographic findings showed bony fusion or bridging in 19 patients, and 25 patients had a pain-free recovery after 1 to 9 months. There was 1 recurrent infection, and 3 patients eventually required an anterior discectomy and fusion. Based on a review of our own cases and those reported in the literature, we stress the importance of spinal tomography in establishing the diagnosis of postoperative disc space infection at a relatively early stage in a patient who is suspected of having this condition on the basis of typical symptoms and signs combined with an elevated sedimentation rate.(ABSTRACT TRUNCATED AT 250 WORDS)