Carotid endarterectomy with regional anesthesia.

The senior author (REH) has changed his technique for performing carotid endarterectomy from the use of general anesthesia to the use of cervical block anesthesia. Because a randomized study was not performed, it is difficult to separate effects of increased surgical experience from those caused by a change in anesthetic regimen. Nonetheless, there has been a substantial decrease in complications, length of hospital stay, and costs concomitant with the change to regional anesthesia; we think there is a causal relationship. The use of cervical block anesthesia has practically eliminated the non-stroke-related complications associated with carotid endarterectomy in our practice. The technique for performing carotid endarterectomy under cervical block anesthesia is described in detail.

Laparoscopic anterior lumbar interbody fusion precipitating pituitary apoplexy.

OBJECTIVE: Pituitary apoplexy may be the first presentation of a previously undiagnosed pituitary adenoma. Although many mechanisms of pituitary apoplexy have been proposed in the literature, the exact pathogenesis remains unclear. Many predisposing events have been implicated in the pathogenesis, however, the role of laparoscopy precipitating pituitary apoplexy has not been previously described. The authors present a case of pituitary apoplexy in a previously undiagnosed pituitary adenoma, which presented in the immediate post-operative period after a laparoscopic anterior lumbar interbody fusion. CLINICAL PRESENTATION: A 45-year-old man presented with a sudden onset of headache, photophobia, diplopia, visual field deficits, and decreased visual acuity in the immediate post-operative period after an uneventful laparoscopic anterior lumbar interbody fusion. Results of computed tomography of the brain revealed a hyperdense suprasellar mass without any signs of subarachnoid blood. The patient underwent magnetic resonance imaging, which revealed a hemorrhagic pituitary tumor with lateral and suprasellar extension, with compression of the cavernous sinus and optic chiasm, respectively. An urgent transsphenoidal decompression of the hemorrhagic pituitary adenoma was performed. Post-operatively, the patient demonstrated marked neurological improvement with recovery of visual acuity and extraocular movements. CONCLUSION: To the authors' knowledge, this is the first case reported in the literature of a laparoscopic procedure precipitating pituitary apoplexy. Recognition of this rare complication of laparoscopic surgery, and the importance of rapid diagnosis and urgent surgical treatment are emphasized.

Stroke: indications for emergent surgical intervention.

As the brain attack message is disseminated throughout our medical community and the awareness of the public increases, neurosurgeons will have the opportunity to treat patients with stroke at a much earlier time in the evolution of the process than we have been accustomed. Are the relatively unimpressive results of acute surgical intervention in patients operated on later in the course of the disease applicable to those who seek medical attention early, within the first few hours of ictus? There is little firm data. However, there is an overwhelming amount of anecdotal and experimental evidence supporting the potential for ultra-early intervention, which frequently should be surgical. New surgical techniques may improve safety and feasibility of emergent operations. In the coming years, diagnostic techniques such as perfusion/diffusion magnetic resonance imaging will allow the clinician to determine who may benefit from intervention. These determinations will be made on physiological data, addressing the issues of tissue viability and degree of compromise of the blood-brain barrier. In the future, the window of opportunity for intervention will not be solely a function of time from ictus or a qualitative impression based on collateral circulation as extrapolated from angiography, transcranial Doppler, or magnetic resonance angiography. These new magnetic resonance imaging techniques, which are beginning to be tested clinically or are still in the developmental stages, will provide the functional data now provided by positron emission tomography and xenon computed tomography, but with improved sensitivity, specificity, and logistical ease. Neurosurgeons have been leaders in stroke care and have provided some of the most important experimental rationale for the brain attack concept. These contributions include demonstration of the ischemic penumbra, the importance of time and potential collateral circulation as factors determining viability of ischemic tissue, and the value of early revascularization and many neuroprotective maneuvers in preserving brain tissue after arterial occlusion. There is every reason to preserve and to enhance the role of the neurosurgeon as a "stroke expert" and as a leading member of the brain attack team. Early access to patients with stroke will offer us the opportunity to test clinically, in a rigorous fashion, the value of surgical revascularization procedures (open or endovascular) and medical maneuvers that we have developed clinically and tested in the laboratory. We have shown, as we did with the bypass study, that neurosurgeons know how to perform these trials and abide by their results, even when they are not to our liking.

Four-level cervical corpectomy.

STUDY DESIGN: Retrospective analysis of 31 cases of cervical spondylotic myelopathy treated by four-level subaxial cervical corpectomy. OBJECTIVE: To determine whether extremes of anterior decompression and fusion have inordinate or unique levels of morbidity. SUMMARY OF BACKGROUND DATA: There is a paucity of data on experience with four-level corpectomy. However, counsel against such surgery can be found. MATERIALS AND METHODS: The records and studies of 31 consecutive cases of cervical spondylotic myelopathy, treated by four-level corpectomy, were retrospectively analyzed. Patients in 26 cases were observed longer than 2 years. No hardware was used in the procedures. External orthosis, worn for 6 months, was a Philadelphia-type collar in 25 patients and a halo vest in 6. RESULTS: Three patients died within 3 weeks of surgery (9.7%). Delayed radiculopathy occurred in four patients after surgery, three had acute graft complications, and one had pseudomeningocele, for a morbidity rate of 25.8%. There was no infection or worsened myelopathy. CONCLUSIONS: No unique morbidity is associated with extremes of subaxial decompression when compared with surgery of lesser extent.

Surgical treatment of internal carotid and posterior communicating artery aneurysms.

Saccular aneurysms of the subarachnoid segment of the internal carotid artery (ICA) are very common. Although some of the aneurysms arising from the subarachnoid ICA have earned the reputation of easy to treat surgically, aneurysms in this region may be complex and quite difficult to repair. Even a simple aneurysm associated with the posterior communicating artery may harbor surprises for the unwary or inexperienced surgeon. This article details the pertinent anatomy of the subarachnoid internal carotid artery and associated saccular aneurysms, provides a guide to their diagnosis and surgical treatment, and briefly reviews some of the published surgical results. Pitfalls and technique tips are highlighted.

Microsurgical treatment of arteriovenous malformations: analysis and comparison with stereotactic radiosurgery.

OBJECT: To compare microsurgical and stereotactic radiosurgical treatment of arteriovenous malformations (AVMs), the authors analyzed a prospective series of 72 consecutive patients who were treated microsurgically for cerebral AVMs by one neurosurgeon. The authors then compared the results of microsurgical treatment with published results of stereotactic radiosurgical treatment of small AVMs. METHODS: Patients were categorized by age, gender, presentation, and preoperative neurological status. The AVMs were categorized by size, location, presence of deep venous drainage, and Spetzler-Martin grade. Outcome was assessed for angiographic obliteration, hemorrhage following treatment, presence of a new, persistent postoperative neurological deficit, and Glasgow Outcome Scale (GOS) score. Ordinal logistic regression was used to model the GOS score and to predict new postoperative deficits. Generalized estimating equations were used to compare published results of microsurgical and stereotactic radiosurgical treatment of AVMs. Kaplan-Meier event-free survival plots were generated to compare the two modalities with respect to hemorrhage following treatment. Overall, six patients (8.3%) exhibited a new persistent neurological deficit postoperatively. Sixty-five patients (90.3%) had a GOS score of 5. Three patients were moderately disabled and four patients were severely disabled. No patient was observed to be in a vegetative state and there were no treatment-related deaths. Seventy-one patients (98.6%) underwent intra- or postoperative angiography. Total excision of the AVM was angiographically confirmed in 70 patients (98.6% of those who underwent angiography). To date no patient has suffered from hemorrhage since the microsurgical treatment. When analysis was confined to patients whose AVMs were smaller than 3 cm in maximum diameter, the authors found a 100% angiographic obliteration rate, no new postoperative neurological deficit, and a good recovery in all patients. An analysis of all patients with Spetzler-Martin Grades I to III resulted in a 100% rate of angiographic obliteration, one patient with a new postoperative neurological deficit, and good recovery in 93% of the patients. Size of the AVM, preoperative neurological status, and patient age are associated with GOS score (for all, p < 0.02). The Spetzler-Martin grading system as well as each component of this system are associated with the development of a new postoperative neurological deficit (for all, p < 0.01). For the entire series there were fewer postoperative hemorrhages and deaths than those mentioned in published series of small AVMs treated with stereotactic radiosurgery. When these patients and published series of patients with microsurgically treated AVMs classified as Grade I to III were compared with similar patients treated radiosurgically there were significantly fewer postoperative hemorrhages (odds ratio = 0.210, p = 0.001), fewer deaths (odds ratio = 0.659, p = 0.019), fewer new posttreatment neurological deficits (odds ratio = 0.464, p = 0.013), and a higher incidence of obliteration (odds ratio = 28.2, p = 0.001) for the microsurgical group. Lifetable analysis confirms the statistically significant difference in hemorrhage-free survival time between the two groups (p = 0.002). CONCLUSIONS: Based on this analysis, microsurgical treatment of Grades I to III AVMs is superior to stereotactic radiosurgery.

Outcome, cost analysis, and long-term follow-up in preterm infants with massive grade IV germinal matrix hemorrhage and progressive hydrocephalus.

OBJECTIVE: The benefit of aggressive management and surgical intervention in preterm infants with massive Grade IV intracranial hemorrhage has been questioned based on the poor outcome of this group of patients despite such therapy. To further delineate this problem, we reviewed the records of premature neonates in this category as to outcome and initial hospital cost. METHODS: We performed a retrospective review of the medical records at our institution from 1977 to 1987 to identify premature neonates who had sustained massive hemorrhagic infarction of one hemisphere in addition to having blood in both ventricles and progressive hydrocephalus. RESULTS: During the study, a total of 52 such patients were identified, only 19 (6 female and 13 male patients) of whom survived. Intellectual function was observed to be greater than 2 standard deviations below the mean in 15 of the 19 patients, between 1 and 2 standard deviations below the mean in 1 of 19, and 1 standard deviation below the mean in 3 of 19. Motor function was as follows: 12 of 19 had marked spastic quadriparesis, 2 of 19 had moderate spastic quadriparesis, 3 of 19 had spastic hemiplegia, 1 of 19 had spastic diplegia, and 1 of 19 had mild spastic hemiparesis. Eleven of 19 had chronic seizure disorders. The first hospitalization cost for the group of patients exceeded, on the average, $150,000 per patient for the 19 long-term survivors. CONCLUSION: As we have previously reported, logistic regression analysis determined that grade of hemorrhage was the only significant predictor of cognitive and motor outcomes. Most premature neonates with massive intracranial hemorrhages do not survive. The outcomes in those who do is very poor and the cost so high that we suggest that until therapeutic intervention exhibits efficacy, the consideration of withdrawal of life support should be presented as an option to the parents of these unfortunate children.

Neuroprotective effects of preischemia intraarterial magnesium sulfate in reversible focal cerebral ischemia.

The known cytoprotective properties of MgSO4 led the authors to study its effects on infarct size in rats when administered intraarterially before reversible focal ischemia. Following an intracarotid infusion of MgSO4 in the amount of 30 mg/kg (24 animals), 90 mg/kg (18 animals), or an equal volume of vehicle (23 animals), middle cerebral artery occlusion was produced in rats by means of an intraluminal suture technique. Reperfusion occurred after 1.5 (42 animals) or 2 hours (23 animals) of ischemia. Automated, volumetric measurements of 2',3',5'-triphenyl-2H-tetrazolium chloride-stained coronal brain sections demonstrated a statistically significant decrease in infarct size for MgSO4 treatment groups compared to controls. Cytoprotection was greater in animals subjected to 1.5 hours of ischemia (28.4% reduction in infarct volume, p < 0.001, Student's t-test), than in those having 2 hours of ischemia (19.3% reduction, p < 0.05). Animals given 90 mg/kg MgSO4 prior to 1.5 hours of ischemia (12 animals) showed a 59.8% reduction in infarct volume compared to controls (11 animals, p < 0.001) and a 43.1% reduction compared to the 30 mg/kg group (11 animals, p < 0.001). Analysis of variance demonstrated the statistically significant effects of MgSO4 doses on infarct volume across all groups (F = 22.95, p < 0.0001). The neuroprotective effect of intraarterial MgSO4 in this model is robust, dose dependent, and related to the duration of ischemia. The compound may be valuable for limiting infarction if given intraarterially before induction of reversible ischemia during cerebrovascular surgery.

Outcome of surgical decompression of the second cervical root for cervicogenic headache.

OBJECTIVE: There is limited information on the surgical treatment of cervicogenic headache (CH). The objective of this study is to analyze the utility of microsurgical decompression of the second cervical (C2) root and ganglion as a treatment for CH. METHODS: Thirty-nine sequential C2 root and ganglion decompressions, performed for the treatment of CH on 35 patients at the Dartmouth-Hitchcock Medical Center during a 70-month period, were analyzed retrospectively. Preoperative factors and intraoperative findings were evaluated with respect to outcome. RESULTS: At a mean follow-up of 21 months, 12 patients (13 sides) were pain free, and 15 were adequately improved (18 sides). Treatment eventually failed in eight patients. No patient, however, was worse after surgical intervention. There was no major morbidity or mortality associated with the operation. The eight patients with unsatisfactory outcome were evaluated for a possible second operation, and four underwent it. One patient of the four is pain free after 28 months, and two gained adequate improvement at 3 and 12 months. The fourth patient required a third operation but has achieved adequate relief at 6 months. Thus, the overall success rate (either pain free or with adequate improvement) was 90%. No specific prognostic factors could be established, other than the accepted diagnostic criteria and successful anesthetic blockade of the C2 root and ganglion. CONCLUSION: The results suggest that microsurgical decompression of the C2 root and ganglion has some utility in treating CH. The accepted diagnostic criteria and success of anesthetic blockade of C2 should identify the subset of patients with CH predominantly caused by C2 root or ganglion effect at this level, which may favor surgical treatment.

Characteristics of patients successfully treated for cervicogenic headache by surgical decompression of the second cervical root.

We have recently reported 90% success in a series of patients undergoing microsurgical decompression of the second cervical (C2) nerve root and ganglion for cervicogenic headache. Review and analysis of our database was carried out in order to cull factors characterizing patients amenable to this surgical treatment. Thirty-five sequential C2 decompressions performed on 31 patients who were pain-free or significantly improved in follow-up were evaluated retrospectively. Preoperative factors and intraoperative findings were analyzed for prognostic significance. The diagnosis of cervicogenic headache was made using established criteria and success of CT-guided C2 anesthetic blockade in alleviating the headache. Numerous historical factors noted preoperatively including age, sex, history of trauma, autonomic symptoms, visual changes, and many others were not able to be well correlated with outcome in univariate analysis. Likewise, no strong correlation could be made for findings on physical examination. Thus, no specific prognostic factors could be established, other than the accepted diagnostic criteria and successful anesthetic blockade of the C2 root and ganglion. These factors should identify the subset of patients with cervicogenic headache predominantly due to C2 root or ganglion effect and thus may favor a surgical treatment.

Characteristics of cerebral gunshot injuries in the rural setting.

The rural CGW population has not yet undergone the metamorphosis experienced by its urban counterparts. Reminiscent of a past era, suicides far outweight homicides. Although many rural firearm injuries involve hunting accidents, these comprise only a small fraction of CGW at best. Similarly, although many rural firearm injuries involve shotguns or rifles, few CGW result from these weapons. Although the number of patients is small, those with shotgun or rifle injuries manifest lower mortality rates. The authors have confirmed the notion that caliber of civilian weapons is difficult to correlate with outcome. The geographic size of the rural catchment area is an important consideration because it must select a population able to withstand transfer. The authors noted an inverse relationship between length of time before arrival at the facility and mortality. The selection phenomenon probably accounts for the reduced mortality found in the authors series versus most others. Prognostic features of individual gunshot wounds are likely to be similar among varied populations when circumstances of the injury are matched. Thus, one expects similar features on initial examination and CT scan to have similar predictive value. The authors confirmed that CGS and specific deficits were strong predictors of outcome. No patient with a GCS score of 5 or less on admission survived. Absent pupillary response, absent brain stem function, presence of respiratory drive or cough only, and posturing were strong indicators of impending death. The authors confirmed the prognostic value associated with CT evidence of intraventricular hemorrhage, transventricular trajectory, transtentorial herniation, massive edema, and bihemispheric injury. Interestingly, presence of extensive facial fractures, an indicator of trajectory, suggested better outcome. Subarachnoid hemorrhage did not reach prognostic significance. Roughly half of the authors' patients had positive serum ethanol levels, although the test was unable to discern prognosis. Abnormality of any coagulation parameter and frank disseminated intravascular coagulation were correlated with poor outcome. Likewise, thrombocytopenia occurring within the first 24 hours was an indicator of poor prognosis. Although prophylactic antibiotics were not used in all cases, the authors encountered no deep or superficial infections in surviving patients. The prevalence of seizures in the authors' series despite prophylactic AED is unusually high. This feature merits further study.

Teratoma of the cavernous sinus: case report.

We report the case of an infant with a mature teratoma of the lateral wall of the cavernous sinus. A complete excision of the tumor was achieved. There was no evidence of recurrence at 1-year follow-up examination. Intracranial teratomas and the anatomy of the lateral wall of the cavernous sinus are briefly reviewed. To our knowledge, this is the first case of a teratoma confined to the cavernous sinus.

Fourteen genetically variant proteins of mouse brain: discovery of two new variants and chromosomal mapping of four loci.

With the description here of variant proteins A13 (pI 5.9, MW 62 kd) and A14 (pI 5.3, MW 26 kd), 14 polypeptides of mouse brain visualized by two-dimensional electrophoresis (2DE) exhibit genetic variation in isoelectric point. Using 22 B X D recombinant inbred strains, we map four of these loci and show that a fifth is independent of known loci. A pI 5.6, 81-kd protein of mouse brain mitochondria designated A1 is demonstrated to be an independent locus closely linked to LY-2 and LVP-1 on mouse chromosome 6. A pI 5.6, 28-kd genetically variant brain polypeptide designated A12 maps to chromosome 1 and shows identity with the known mouse locus LTW-4. The locus for A8 is not closely linked to any previously mapped locus. However, the locus for the newly described variant A13 shows 3 of 18 recombinants with the DNA polymorphism RN7S-2 and 2 of 18 recombinants with HC (hemolytic complement) and is thus probably located proximally to HC near the centromere of chromosome 2. Genetic and biochemical evidence is presented for the identification of A14 as ALP-1 (apolipoprotein 1), mapping to chromosome 9. In addition to these 13 genetically variant polypeptides, the positions of 12 other polypeptides which have been identified on 2DE gels of mouse brain are given.