Brian K. Willis

Burr-hole versus twist-drill drainage for theevacuation of chronic subdural haematoma:a comparison of clinical results

BACKGROUND Most neurosurgeons remove clinically symptomatic subdural haematomata, but the techniques they choose remain controversial. METHOD The results from sixty-two patients diagnosed with chronic subdural haematoma were evaluated for technique, postoperative computerized tomography (CT) scan results, and complications. RESULTS Eleven patients had haematomata evacuated using twist-drill plus drain, 37 patients had haematomata evacuated with burr-hole only, and 14 patients were evacuated with burr-hole plus drain. Of the patients who underwent twist-drill and closed system drainage (CSD), 43% had smaller lesions on CT follow-up scans, as compared with 74% of those who underwent the burr-hole only procedure, and 65% with burr-holes with drains. Clinical outcome results showed that 64% of twist-drill and CSD patients deteriorated as compared with 16% of those with burr-hole only and 7% with burr-holes and CSDs. Sixty-four per cent of twist-drill patients required repeat evacuations as compared with 11% of those with burr-holes only, and 7% with burr-holes plus drains. CONCLUSION The results at our institution indicate that burr-hole evacuation for chronic subdural haematoma is superior to twist-drill evacuation with respect to clinical outcomes and complications.

Ventriculosubgaleal Shunts for Posthemorrhagic Hydrocephalus in Premature Infants

Objective: The early management of posthemorrhagic hydrocephalus in premature infants is challenging and controversial. These infants need a temporary cerebrospinal fluid (CSF) diversion procedure until they gain adequate weight, and the blood and protein levels in CSF are reasonably low before permanent shunt can be placed. Various options are available with their associated advantages and disadvantages. Ventriculosubgaleal shunts have been recommended as a more physiologic and less invasive means of achieving this goal. We have performed this procedure in 6 premature infants to evaluate their effectiveness and complications. Methods: Six consecutive premature infants with posthemorrhagic hydrocephalus underwent placement of ventriculosubgaleal shunts over a 1-year period of time. We reviewed their clinical and imaging progress to assess the ability of the shunt to control hydrocephalus and the complication rates. Results: In all 6 patients, the ventriculosubgaleal shunt controlled the progression of hydrocephalus as assessed by clinical and imaging parameters. A permanent shunt was avoided in 1 patient (16.6%). However, 4 patients developed shunt infections, 1 involving the ventriculosubgaleal shunt itself, and 3 immediately after conversion to ventriculoperitoneal shunt. The total infection rate of the series was 66.6%. All infections were caused by staphylococcus species. There was only a 1% shunt infection rate in our institution for all nonventriculosubgaleal shunts during the same period of time. Conclusion: Placement of ventriculosubgaleal shunts for interim CSF diversion in neonates with posthemorrhagic hydrocephalus is effective as a temporary method of CSF diversion. However, our experience has shown that it is associated with a unacceptably high CSF infection rate. A potential cause for infection is CSF stasis just beneath the extremely thin skin of the premature infants, promoting colonization by skin flora. CSF sampling before conversion to a permanent shunt and replacement of the proximal hardware, which has been in situ for a prolonged period, may decrease the infection rates. At present, the procedure is no longer performed at our institution.

Ventricular reservoirs and ventriculoperitoneal shunts for premature infants with posthemorrhagic hydrocephalus : an institutional experience

OBJECT The aim of the study was to analyze the outcome of surgical treatment for posthemorrhagic hydrocephalus in premature infants. METHODS From 1990 to 2006, 32 premature infants underwent surgical treatment for posthemorrhagic hydrocephalus, and their charts were retrospectively reviewed to analyze the complications and outcome with respect to shunt revisions. Multivariate analysis and time series were used to identify factors that influence the outcome in terms of shunt revisions. RESULTS The mean gestational age was 27+/-3.3 weeks, and mean birth weight was 1192+/-660 g. Temporary reservoir placement was performed in 15 patients, while 17 underwent permanent CSF diversion with a ventriculoperitoneal (VP) shunt. In 2 patients, reservoir tapping alone was sufficient to halt the progression of hydrocephalus; 29 patients received VP shunts. The mean follow-up period was 37.3 months. The neonates who received VP shunts first were significantly older (p=0.02) and heavier (p=0.04) than those who initially underwent reservoir placement. Shunts were revised in 14 patients; 42% of patients in the reservoir group had their shunts revised, while 53% of infants who had initially received a VP shunt required a revision. The revision rate per patient in the reservoir group was half that in the direct VP shunt group (p=0.027). No patient in the reservoir group had >2 revisions. Shunt infections developed in 3 patients (10.3%), and 2 patients in the reservoir group died of nonneurological issues related to prematurity. CONCLUSIONS Birth weight and age are useful parameters in decision making. Preterm neonates with low birth weights benefit from initial CSF drainage procedures followed by permanent CSF diversion with respect to the number of shunt revisions.

Infection rate with replacement of bone fragment in compound depressed skull fractures.

BACKGROUND Traditional management of compound depressed skull fractures entails elevation and removal of all bone fragments with delayed cranioplasty. Bone fragment removal is intended to reduce the potential for infection. However, bone fragment removal often necessitates a second operation to repair the resultant calvarial defect. This study examines the postoperative infection rate when bone fragments are replaced primarily. METHODS A retrospective study was carried out of all patients admitted with the diagnosis of compound depressed skull fracture to a university hospital from 1991 to 1996. RESULTS Of 52 patients with the diagnosis of compound depressed skull fracture treated at our university hospital over the past 5 years, 32 underwent elevation and repair within 72 hours. All patients except one received antibiotics during surgery and for at least 1.5 days after surgery. Follow-up averaged just over 22 months. In all 32 consecutive patients treated with debridement and elevation of compound depressed skull fractures with primary replacement of bone fragments within 72 hours of injury, there were no infectious sequelae. CONCLUSIONS Immediate replacement of bone fragments in compound depressed skull fractures does not increase the risk of infectious complications.

Gamma Knife Radiosurgery for Brain Metastases: Do Patients Benefit from Adjuvant External-Beam Radiotherapy? An 18-Month Comparative Analysis

Objective: To analyze 18 months of results of gamma knife stereotactic radiosurgery in the treatment of brain metastases and determine factors affecting outcome by examining the effectiveness of additional external-beam radiotherapy (XRT). Materials and Methods: Between January 2000 and September 2001, 61 patients with 103 tumors diagnosed as cerebral metastases were treated with gamma knife. Mean patient age was 57 years (range = 36–81). Lung carcinoma (55.7%) was the most common primary cancer, followed by melanoma (14.8%) and breast carcinoma (11.5%). Mean KPS of the patients was 70 (range = 50–90). Twenty-seven patients had solitary metastases while 34 had multiple tumors. Forty-three patients (59 tumors in total) received only radiosurgery, while 18 patients (44 tumors in total) had prior XRT. Tumor volume ranged from 0.5 to 33 cm3 (mean = 9.74 cm3). Mean marginal dose prescription to the tumor was 15 Gy (range = 11–21 Gy). Results: Median follow-up was 11 months. Twenty-one patients (34.4%) were alive at last follow-up and 40 (65.6%) had died. Seventeen deaths (42.5%) were reported to be due to progressive brain disease, while 23 deaths (57.5%) were due to uncontrolled primary. Control of the treated lesions was achieved in 45 patients (73.8%) and 84 tumors (81.6%). Mean overall survival of the patients is 8 months (range = 1–19 months). The actuarial 12-month tumor control rate using the Kaplan-Meier method for this series is 68.2 ± 0.06%. Results of the log-rank test revealed that younger age (<55 years), small tumor volume (<10 cm3), and increasing tumor dose (>15 Gy) correlated with improved brain disease-free survival (p < 0.05). Overall survival, local tumor control rate and the freedom from brain disease period (based on the appearance of new brain tumors after radiosurgery) were analyzed separately for the groups receiving radiosurgery alone and those with prior XRT to detect any additional benefit of XRT. No statistically significant difference was found between the two groups for any of the considered outcomes. Conclusion: Gamma knife stereotactic radiosurgery is a safe and effective treatment option for patients with cerebral metastases. It provides survival benefits and improves quality of life by achieving excellent control of the brain disease, irrespective of patients’ age or number of brain tumors. The addition of XRT in younger patients with small brain metastases does not improve survival and/or control of the brain disease.

Selective intraoperative angiography in intracranial aneurysm surgery: intraoperative factors associated with aneurysmal remnants and vessel occlusions.

BACKGROUND The objective of this study was to assess the role of selective intraoperative angiography and to analyze the factors associated with faulty clip application. METHODS Two hundred thirty-eight patients undergoing surgery for intracranial aneurysms were studied consecutively for intraoperative angiography (IOA)-related events. The procedure was performed in 155 operations. Demographic details, clinical grade of the patient, location and size of the aneurysm, intraoperative rupture, application of the temporary clip, IOA findings, and final outcome were analyzed. RESULTS In the 155 patients in the series, there were 125 anterior circulation aneurysms and 30 on the vertebrobasilar system. Aneurysms were smaller than 10 mm in 63% of the patients, and 19 were giant aneurysms. Thirty-eight percent were unruptured, 36% were Hunt and Hess Grades I and II, 21% were Grade III, and 5% were Grades IV and V. An intraoperative rupture occurred in 18 operations. Intraoperative angiography was normal in 88%; in 11 cases (7%) there was a residual neck, and in 8 (5%), occlusion of the artery was observed. An incomplete clipping was significantly related to intraoperative rupture of the aneurysm (p < 0.008) and anterior location of the aneurysm (p = 0.05), whereas vessel occlusion had a significant association with posterior location of the aneurysm (p < 0.0005). An eventful IOA had significant association with poor outcome (p < 0.003). CONCLUSION Intraoperative rupture and a posterior location of the aneurysm had a significant correlation with residual aneurysm and vessel occlusion, respectively. The use of IOA is justified in aneurysms associated with these factors.

Magnetic resonance imaging evaluation of acute spine trauma

A comparison study of magnetic resonance imaging (MR), computed tomography (CT), and plain film evaluation of 113 consecutive spine trauma cases was conducted. The rate of true-positive findings (sensitivity) on MR was shown to be significantly higher than for CT or plain films in the evaluation of soft tissue or ligamentous injury (P<0.001). MR had a significantly lower rate of positive findings for fracture than CT (P<0.001) and was also shown to be significantly less sensitive for fracture than plain films (P<0.001). Spinal cord contusion, epidural hematoma, high-grade stenosis, and ligamentous or soft tissue injury were best evaluated with MR.MR, CT, and plain films are all important modalities for the evaluation of acute spine trauma. It is recommended that, after clinical examination, patients with spine trauma be evaluated first by plain film. If there is clinical or radiologic suspicion for acute spine injury, MR should be the next diagnostic procedure performed. If MR is positive for acute injury, CT may be indicated. CT best defines the extent of bony injury, and MR the extent of soft tissue injury, intrinsic spinal cord pathology, and extrinsic dural sac compression.

Metastatic disease in the cerebellum : The LSU experience in 1981-1993

We retrospectively determined the outcome of management of metastatic disease in the cerebellum (MDC) in 45 patients because MDC is considered to be more immediately life-threatening than metastases in other intracranial locations. Treatment consisted of tumor resection and radiotherapy (RR; n = 11) or of radiotherapy alone (RA; n = 34). Significant differences in the median survival (15 months for RR and 3 months for RA, p = 0.005) and in survival rates at 1 year (61 +/- 30% for RR and 9 +/- 10% for RA, p < 0.001) and at 2 years (15 +/- 22% for RR and 0% for RA, p < 0.05) were noted. This combined management program of surgery followed by radiotherapy for MDC produced a worthwhile gain in survival.

Pediatric spinal blastomycosis: case report.

A 5-year-old male patient presented with flank pain, limping, weight loss, and cachexia. Magnetic resonance imaging revealed destructive vertebral changes, an epidural mass, psoas abscesses, and lack of involvement of the disc spaces. Blastomyces dermatitidis was isolated from a needle aspiration specimen. Sparing of the disc spaces, an unusual finding, suggested that the spread of infection was by way of paravertebral structures and surrounding potential spaces. Management was simplified by using gadolinium contrast-enhanced magnetic resonance imaging, which indicated that the epidural mass was mainly solid, thereby obviating abscess drainage.

Posthemorrhagic hydrocephalus and shunts: what are the predictors of multiple revision surgeries?

OBJECT Cerebrospinal fluid shunts in patients with posthemorrhagic hydrocephalus are prone to failure, with some patients at risk for multiple failures. The objective of this study was to identify factors leading to multiple failures. METHODS The authors performed a retrospective analysis of cases of posthemorrhagic hydrocephalus requiring neurosurgical intervention between 1982 and 2010. RESULTS In the 109 cases analyzed, 54% of the patients were male, their mean birth weight was 1223 g, and their mean head circumference 25.75 cm. The mean duration of follow-up was 6 years, and 9 patients died. Grade III intraventricular hemorrhage was seen in 47.7% and Grade IV in 43.1%. Initial use of a ventricular access device was needed in 65 patients (59.6%), but permanent CSF shunting was needed in 104 (95.4%). A total of 454 surgical procedures were performed, including 304 shunt revisions in 78 patients (71.6%). Detailed surgical notes were available for 261 of these procedures, and of these, 51% were proximal revisions, 13% distal revisions, and 17% total shunt revisions. Revision rates were not affected by catheter type, patient sex, presence of congenital anomalies, or type of hydrocephalus. Age of less than 30 days at the initial procedure was associated with decreased survival of the first shunt. Regression analysis revealed that lower estimated gestational age (EGA) and obstructive hydrocephalus were significant predictors of multiple shunt revisions. CONCLUSIONS We found a high rate of need for permanent CSF shunts (95.4%) in patients with posthemorrhagic hydrocephalus. Shunt revision was required in 71.6% of patients, with those with lower birth weight and EGA at a higher risk for revisions.