Neurosurgery Blog

J Neurosurg 113:581–584, 2010. DOI: 10.3171/2009.10.JNS09930

Traumatic brain injury (TBI) is a major cause of serious morbidity and mortality. The incidence is 100–500/100,000 inhabitants/year. Chronic pituitary dysfunction is increasingly recognized after TBI. To define the incidence of endocrine dysfunction and risk factors, the authors describe a prospectively assessed group of patients in whom they documented hormonal functions, early diagnosis, and treatment of neuroendocrine dysfunction after TBI.

Methods. Patients aged 18–65 years were prospectively observed from the time of injury to 1 year postinjury; the Glasgow Coma Scale score ranged from 3 to 14. Patients underwent evaluation of hormonal function at the time of injury and at 3, 6, and 12 months postinjury. Magnetic resonance imaging was also conducted at 1 year postinjury.

Results. During the study period, 89 patients were observed. The mean age of the patients was 36 years, there were 23 women, and the median Glasgow Coma Scale score was 7. Nineteen patients (21%) had primary hormonal dysfunction. Major deficits included growth hormone dysfunction, hypogonadism, and diabetes insipidus. Patients in whom the deficiency was major had a worse Glasgow Outcome Scale score, and MR imaging demonstrated empty sella syndrome more often than in patients without a deficit.

Conclusions. To the authors’ knowledge, this is the third largest study of its kind worldwide. The incidence of chronic hypopituitarism after TBI was higher than the authors expected. After TBI, patients are usually observed on the neurological and rehabilitative wards, and endocrine dysfunction can be overlooked. This dysfunction can be life threatening and other clinical symptoms can worsen the neurological deficit, extend the duration of physiotherapy, and lead to mental illness. The authors recommend routine pituitary hormone testing after moderate or severe TBI within 6 months and 1 year of injury.

Neurosurgery 67:743-748, 2010 DOI: 10.1227/01.NEU.0000374770.09140.FB

We retrospectively evaluated whether antiplatelet preparation lowered the thromboembolic complication rate during the perioperative period.

METHODS:We reviewed 328 elective coil embolization procedures in which only microcatheters were used for coiling. No antiplatelet medication was prescribed before the procedure in 95 cases (29%, group 1), whereas antiplatelet therapy was used in 233 cases (71%, group 2; 61 [18.6%] with a single agent [aspirin or clopidogrel] and 172 [52.4%] with both agents). Antiplatelet agents were not given after coiling unless atherosclerosis, severe coil protrusion, or a thromboembolic complication occurred during the procedure. A thromboembolic complication was defined as a procedural thromboembolic event or transient ischemic attack or stroke occurring within 2 days of embolization.

RESULTS: Thromboembolic complications occurred in 11 cases (3.4%): 6 (6.3%) in group 1 and 5 (2.1%) in group 2 (P = .085). In 195 cases (59.5%) treated by the single microcatheter technique, the risk of thromboembolic complications was low and not affected by antiplatelet preparation (1.8% [no preparation] vs 2.2% [preparation]; P = 1.000). However, in 133 cases (40.5%) treated by the multiple microcatheter technique, antiplatelet preparation significantly reduced the thromboembolic complication risk by 85.2% (12.8% [no preparation] vs 2.1% [preparation]; odds ratio, 0.148; 95% confidence interval, 0.027-0.798; P = .023). The aneurysms treated by the multiple microcatheter technique had more complex configurations for coiling (P < .001). The risk of hemorrhage was not increased by antiplatelet preparation (P = .171).

CONCLUSION: Antiplatelet preparation lowered the periprocedural thromboembolic complication rate in unruptured aneurysms treated by the multiple microcatheter technique and did not increase the risk of hemorrhage. Therefore, antiplatelet preparation can help to reduce complications in patients in whom technical difficulties are expected without the risk of hemorrhage.

J Neurosurg Spine 13:403–406, 2010.DOI: 10.3171/2010.3.SPINE09657

Pedicle screws placed in the thoracic, lumbar, and sacral spine occasionally come in contact with the aorta, vena cava, or iliac vessels. When such screws are seen on postoperative imaging in an asymptomatic patient, the surgeon must decide whether it is riskier to revise the screw or to observe it. The authors hypothesized that the incidence of screw placement causing perioperative vessel injury is low and, further, that screws placed in contact with major vessels do not always result in vessel injury.

Methods. A retrospective review of the operative records of 182 consecutive patients undergoing thoracic, lumbar, and lumbosacral pedicle screw fusion was performed to determine the frequency of intraoperative vessel injury. Postoperative imaging for 107 patients was available to determine the incidence of screws in contact with major vessels. Charts were examined to determine if any adverse sequelae had resulted from malpositioned screws. Patient outcomes were documented.

Results. There were no intraoperative vessel injuries or deaths in 182 consecutive operations. One hundred seven patients with available postoperative films had 680 pedicle screws placed between T-3 and the sacrum during 115 operations. No patient had arterial screw penetration or deformation on postoperative imaging. Thirty-three of the 680 inserted screws were in contact with a major vessel on routine postoperative imaging. The contacted vessels included the aorta (4 cases), the iliac artery (7 cases), and the iliac veins (22 cases). Patients were followed up until death or November 2009, for a mean follow-up of 44 months (median 44 months, range 5–109 months). None of the patients with vessel contact was noted to suffer symptoms or sequelae as a result of vessel contact. Radiographic follow-up as long as 50 months after surgery revealed no detectable vessel abnormality at the contacted site.

Conclusions. Placing pedicle screws in contact with major vessels is a known risk of spinal surgery. The risk of repositioning a screw in contact with a major vessel but causing no symptoms must be weighed against the relative risk of leaving it in place.

J Neurosurg 113:161–166, 2010.DOI: 10.3171/2010.2.JNS09950

In select patient populations, hyperglycemia has been shown to increase the risk of surgical site infection (SSI), whereas stringent glucose control has improved outcomes. To date, no study has focused on whether SSIs in patients with brain tumors undergoing resection are associated with hyperglycemia. Methods. The authors performed a retrospective chart review of patients who underwent a craniotomy after receiving a diagnosis of brain tumor. From 2001 to 2008, 2485 patients underwent a craniotomy for tumor resection at the Brain Tumor & Neuro-Oncology Center at the Cleveland Clinic. Fifty-seven of these patients (2.3%) developed SSIs postoperatively. A matched case-control study design was used, with 57 patients who developed SSIs after craniotomy (cases) matched with 57 patients who did not develop SSIs (controls). The results were analyzed using both univariate and multivariate conditional logistic regression. Results. Glucose level was not a significant factor in postoperative SSI (p = 0.83) after adjusting for duration of surgery and adherence to antibiotic prophylaxis. However, duration of surgery was significantly associated with postoperative SSI (p = 0.047). Conclusions. For patients who undergo craniotomy for definitive resection of a brain tumor, duration of surgery described more variation in the model to predict SSI than blood glucose levels.

SPINE Volume 35, Number 17, pp 1595–1601.

Study Design. A retrospective study of clinical results of operative treatment for degenerative lumbar scoliosis.

Objective. To determine the risk factors of sagittal decompensation after long instrumentation and fusion to L5 or S1. Summary of Background Data. Little is known about the risk factors for sagittal decompensation, which was defined in this study as sagittal C7 plumb falling anterior 8 cm from the posterosuperior corner of the sacrum.

Methods. Forty-five patients (mean age: 64.4 year) with adult degenerative lumbar scoliosis were reviewed retrospectively with a minimum 2 years. The mean number of levels fused was 6.1  1.6 segments. The upper instrumented vertebra ranged from T9 to L2. The lower instrumented vertebra was L5 and S1 in 24 and 21 patients, respectively.

Results. Sagittal decompensation (SD) developed in 19 patients. The most significant risk factors of SD were preoperative sagittal imbalance and high pelvic incidence. The preoperative sagittal C7 plumb was more positive (67.9 mm) in the decompensation group than in the balance group (37.0 mm) (P = 0.002). There was a significant difference in pelvic incidence between 61.7° in the decompensation and 54.9° in the balance group (P = 0.01). The preoperative lumbar lordosis was hypolordotic in the decompensation group, however, it was not found to be a risk factor. Pseudarthrosis was identified at the lumbosacral junction in 5 patients, and 4 of them (80%) had SD. SD developed in 55% of patients who had loosening of the distal screws and 50% of patients with hypolordotic lumbar fusion. Distal adjacent segment disease was more likely to cause SD than proximal adjacent segment disease.

Conclusion. Sagittal decompensation is common after long posterior instrumentation and fusion for degenerative lumbar scoliosis. It is mostly associated with complications at the distal segments, including pseudarthrosis and implant failure at the lumbosacral junction. Restoration of optimal lumbar lordosis and secure lumbosacral fixation is necessary especially in patients with preoperative sagittal imbalance and high pelvic incidence in order to prevent sagittal decompensation after surgery. Key words: adult spinal deformity, degenerative lumbar scoliosis, sagittal imbalance, sagittal decompensation, risk factor

J Neurosurg Spine 13:144–157, 2010.DOI: 10.3171/2010.3.SPINE09369

The overall incidence of complications or adverse events in spinal surgery is unknown. Both prospective and retrospective analyses have been performed, but the results have not been critically assessed. Procedures for different regions of the spine (cervical and thoracolumbar) and the incidence of complications for each have been reported but not compared. Authors of previous reports have concentrated on complications in terms of their incidence relevant to healthcare providers: medical versus surgical etiology and the relevance of perioperative complications to perioperative events. Few authors have assessed complication incidence from the patient’s perspective. In this report the authors summarize the spine surgery complications literature and address the effect of study design on reported complication incidence.

Methods. A systematic evidence-based review was completed to identify within the published literature complication rates in spinal surgery. The MEDLINE database was queried using the key words “spine surgery” and “complications.” This initial search revealed more than 700 articles, which were further limited through an exclusion process. Each abstract was reviewed and papers were obtained. The authors gathered 105 relevant articles detailing 80 thoracolumbar and 25 cervical studies. Among the 105 articles were 84 retrospective studies and 21 prospective studies. The authors evaluated the study designs and compared cervical, thoracolumbar, prospective, and retrospective studies as well as the durations of follow-up for each study.

Results. In the 105 articles reviewed, there were 79,471 patients with 13,067 reported complications for an overall complication incidence of 16.4% per patient. Complications were more common in thoracolumbar (17.8%) than cervical procedures (8.9%; p < 0.0001, OR 2.23). Prospective studies yielded a higher incidence of complications (19.9%) than retrospective studies (16.1%; p < 0.0001, OR 1.3). The complication incidence for prospective thoracolumbar studies (20.4%) was greater than that for retrospective series (17.5%; p < 0.0001). This difference between prospective and retrospective reviews was not found in the cervical studies. The year of study publication did not correlate with the complication incidence, although the duration of follow-up did correlate with the complication incidence (p = 0.001).

Conclusions. Retrospective reviews significantly underestimate the overall incidence of complications in spine surgery. This analysis is the first to critically assess differing complication incidences reported in prospective and retrospective cervical and thoracolumbar spine surgery studies

Acta Neurochir (2010) 152:1197–1205. DOI 10.1007/s00701-010-0640-7

Early infarction that occurs at the time of initial subarachnoid hemorrhage (SAH) due to rupture of an aneurysm is a poorly understood phenomenon. We investigate the frequency of early infarction using diffusion-weighted images (DWI) at the time of admission. We then discuss the pathogenesis of infarction.

Materials and methods This study included 85 SAH patients who underwent serial DWI on admission. Early infarction detected by DWI and clinical features were investigated retrospectively.

Results The overall incidence of DWI-detected early infarction at the time of SAH onset was 8% (7 of 85 cases). In all seven patients, early infarctions were asymptomatic on admission. Types of early infarction seen on DWI included infarcts occurring in the territory of the vessel harboring a ruptured aneurysm (solitary, three cases) and infarcts occurring outside the territory of the vessel (multiple, two cases; solitary, two cases). Six of seven patients eventually developed delayed ischemic neurological deficit (DIND) and computed tomography (CT)-detected and DWI-detected delayed extensive infarction. Four of seven patients with early infarction had an unfavorable outcome. The occurrence of DWI-detected early infarction on admission was significantly correlated with delayed angiographic vasospasm, DIND, CT-detected delayed infarction, DWI-detected delayed infarction, and unfavorable outcome.

Conclusions In the present study, DWI-detected early infarction at the time of SAH onset was correlated with the occurrence of delayed extensive ischemic lesions. We believe that performing DWI at the time of admission is useful for evaluating the primary ischemic insult, which might play an important role in the pathogenesis of early brain injury and delayed vasospasm-related complications.

Neurosurgery 67:187-191, 2010 DOI: 10.1227/01.NEU.0000370247.11479.B6

Ventriculostomy infections create significant morbidity. To reduce infection rates, a standardized evidence-based catheter insertion protocol was implemented. A prospective observational study analyzed the effects of this protocol alone and with antibiotic-impregnated ventriculostomy catheters.

OBJECTIVE: To compare infection rates after implementing a standardized protocol for ventriculostomy catheter insertion with and without the use of antibiotic-impregnated catheters.

METHODS: Between 2003 and 2008, 1961 ventriculostomies and infections were documented. A ventriculostomy infection was defined as 2 positive CSF cultures from ventriculostomy catheters with a concurrent increase in cerebrospinal fluid white blood cell count. A baseline (preprotocol) infection rate was established (period 1). Infection rates were monitored after adoption of the standardized protocol (period 2), institution of antibioticimpregnated catheter A (period 3), discontinuation of antibiotic-impregnated catheter A (period 4), and institution of antibiotic-impregnated catheter B (period 5).

RESULTS: The baseline infection rate (period 1) was 6.7% (22/327 devices). Standardized protocol (period 2) implementation did not change the infection rate (8.2%; 23/281 devices). Introduction of catheter A (period 3) reduced infections to 1.0% (2/195 devices, P = .0005). Because of technical difficulties, this catheter was discontinued (period 4), resulting in an increase in infection rate (7.6%; 12/157 devices). Catheter B (period 5) significantly decreased infections to 0.9% (9 of 1001 devices, P = .0001). The Staphylococcus infection rate for periods 1, 2, and 4 was 6.1% (47/765) compared with 0.2% (1/577) during use of antibioticimpregnated catheters (periods 3 and 5).

CONCLUSION: The use of antibiotic-impregnated catheters resulted in a significant reduction of ventriculostomy infections and is recommended in the adult neurosurgical population.

Acta Neurochir (2010) 152:749–761.DOI 10.1007/s00701-009-0595-8

Pituitary apoplexy is a rare and life-threatening complication occurring in 0.6–10.5% of all cases of pituitary adenomas. Although the association between pituitary apoplexy and visual dysfunction has been recognized for a long time, the optimal management of this problem still remains controversial. The purpose of this overview was to present the surgical experience by analyzing the literature on the management of pituitary apoplexy for better treatment of these cases.

Materials and method To establish a new guideline for the surgical treatment of this entity, publications reported during the last century and databases containing medical literature were analyzed. In addition, an illustrative case with pituitary apoplexy presenting with complaints of sudden onset severe headache associated with nausea, vomiting, and a sudden loss of vision was described. In fact, the experience in our complicated patient prompted us to review the available literature on the management of pituitary apoplexy to date.

Conclusions Based on an overview of 186 cases of apoplectic pituitary adenoma presenting with monocular or binocular blindness, we highlight the importance of correct diagnosis and an early, but not necessarily emergency, surgery within the first week of admission to optimize visual outcome of such patients. The illustrative case further exemplifies the value of close interaction between members of the management team for optimal outcome.

Neurosurgery 66:1005-1012, 2010 DOI: 10.1227/01.NEU.0000367721.73220.C9

Gross total resection of intradural spinal tumors can be achieved in the majority of cases with preservation of long-term neurological function. However, postoperative progressive spinal deformity complicates outcome in a subset of patients after surgery. We set out to determine whether the use of laminoplasty (LP) vs laminectomy (LM) has reduced the incidence of subsequent spinal deformity following intradural tumor resection at our institution.

METHODS:We retrospectively reviewed the records of 238 consecutive patients undergoing resection of intradural tumor at a single institution. The incidence of subsequent progressive kyphosis or scoliosis, perioperative morbidity, and neurological outcome were compared between the LP and LM cohorts.

RESULTS: One hundred eighty patients underwent LM and 58 underwent LP. Patients were 46 ± 19 years old with median modified McCormick score of 2. Tumors were intramedullary in 102 (43%) and extramedullary in 102 (43%). All baseline clinical, radiographic, and operative variables were similar between the LP and LM cohorts. LP was associated with a decreased mean length of hospitalization (5 vs 7 days; P = .002) and trend of decreased incisional cerebrospinal fluid leak (3% vs 9%; P = .14). Following LP vs LM, 5 (9%) vs 21 (12%) patients developed progressive deformity (P = .728) a mean of 14 months after surgery. The incidence of progressive deformity was also similar between LP vs LM in pediatric patients < 18 years of age (43% vs 36%), with preoperative scoliosis or loss of cervical/lumbar lordosis (28% vs 22%), or with intramedullary tumors (11% vs 11%).

CONCLUSION: LP for the resection of intradural spinal tumors was not associated with a decreased incidence of short-term progressive spinal deformity or improved neurological function. However, LP may be associated with a reduction in incisional cerebrospinal fluid leak. Longer-term follow-up is warranted to definitively assess the long-term effect of LP and the risk of deformity over time.

Neurosurgery 66:714-721, 2010 DOI: 10.1227/01.NEU.0000367451.59090.D7

More elderly patients are presenting with intracranial aneurysms. Many are poor surgical candidates and often undergo endovascular treatment.

OBJECTIVE: We present our experience with embolization in elderly patients.

METHODS:We performed a retrospective review of a prospective database of elderly patients treated with coil embolization for intracranial aneurysms.

RESULTS: In a period of 16 years, 205 aneurysms were treated in 196 individuals (age range, 70–96 years; mean age, 77.3 years), including 159 females (average follow-up, 16.2 months). Ninety-seven patients presented with unruptured aneurysms, and 99 patients presented after subarachnoid hemorrhage; the diagnosis was confirmed by computed tomographic scan or lumbar puncture. Complete occlusion was achieved in 53 aneurysms (26%), with a neck remnant in 127 (62%), incomplete occlusion in 13 (6%), and 12 unsuccessful attempts. Postembolization, 89.3% of patients were neurologically intact or unchanged, whereas 8.7% had new deficits. Four patients died. By modified Rankin Scale score, at last clinical evaluation, 128 patients (65%) had a good outcome. Follow-up angiograms were available for 113 aneurysms; they revealed that 62% were unchanged, 21% were further thrombosed, and 17% had recanalized. Three aneurysms ruptured after treatment during follow-up. Rupture was not associated with incomplete occlusion or neck remnant results (P = .6). Twenty-five aneurysms required reembolization. Reembolization was not associated with new deficits or death (odds ratio, 0.56; 95% confidence interval, 0.19–1.58; P = .27).

CONCLUSION: Coil embolization of intracranial aneurysms is safe and effective in the elderly. Preembolization clinical condition strongly correlates with clinical outcome. Incomplete embolizations are not associated with a higher rerupture risk. Additional embolization does not affect the clinical results.

JAMA. 2010;303(13):1259-1265

In recent decades, the fastest growth in lumbar surgery occurred in older patients with spinal stenosis. Trials indicate that for selected patients, decompressive surgery offers an advantage over nonoperative treatment, but surgeons often recommend more invasive fusion procedures. Comorbidity is common in older patients, so benefits and risks must be carefully weighed in the choice of surgical procedure.

Objective: To examine trends in use of different types of stenosis operations and the association of complications and resource use with surgical complexity.

Design, Setting, and Patients: Retrospective cohort analysis of Medicare claims for 2002-2007, focusing on 2007 to assess complications and resource use in US hospitals. Operations for Medicare recipients undergoing surgery for lumbar stenosis (n=32 152 in the first 11 months of 2007) were grouped into 3 gradations of invasiveness: decompression alone, simple fusion (1 or 2 disk levels, single surgical approach), or complex fusion (more than 2 disk levels or combined anterior and posterior approach).

Main Outcome Measures: Rates of the 3 types of surgery, major complications, postoperative mortality, and resource use.

Results: Overall, surgical rates declined slightly from 2002-2007, but the rate of complex fusion procedures increased 15-fold, from 1.3 to 19.9 per 100.000 beneficiaries. Lifethreatening complications increased with increasing surgical invasiveness, from 2.3% among patients having decompression alone to 5.6% among those having complex fusions. After adjustment for age, comorbidity, previous spine surgery, and other features, the odds ratio (OR) of life-threatening complications for complex fusion compared with decompression alone was 2.95 (95% confidence interval [CI], 2.50-3.49). A similar pattern was observed for rehospitalization within 30 days, which occurred for 7.8% of patients undergoing decompression and 13.0% having a complex fusion (adjusted OR, 1.94; 95% CI, 1.74-2.17). Adjusted mean hospital charges for complex fusion procedures were US $80.888 compared with US $23.724 for decompression alone.

Conclusions: Among Medicare recipients, between 2002 and 2007, the frequency of complex fusion procedures for spinal stenosis increased while the frequency of decompression surgery and simple fusions decreased. In 2007, compared with decompression, simple fusion and complex fusion were associated with increased risk of major complications, 30-day mortality, and resource use.

Lancet Neurol 2010; 9: 353–62. DOI:10.1016/S1474- 4422(10)70057-0

The International Carotid Stenting Study (ICSS) of stenting and endarterectomy for symptomatic carotid stenosis found a higher incidence of stroke within 30 days of stenting compared with endarterectomy. We aimed to compare the rate of ischaemic brain injury detectable on MRI between the two groups.

Methods: Patients with recently symptomatic carotid artery stenosis enrolled in ICSS were randomly assigned in a 1:1 ratio to receive carotid artery stenting or endarterectomy. Of 50 centres in ICSS, seven took part in the MRI substudy. The protocol specified that MRI was done 1–7 days before treatment, 1–3 days after treatment (post-treatment scan), and 27–33 days after treatment. Scans were analysed by two or three investigators who were masked to treatment. The primary endpoint was the presence of at least one new ischaemic brain lesion on diffusion-weighted imaging (DWI) on the post-treatment scan. Analysis was per protocol. This is a substudy of a registered trial, ISRCTN 25337470.

Findings: 231 patients (124 in the stenting group and 107 in the endarterectomy group) had MRI before and after treatment. 62 (50%) of 124 patients in the stenting group and 18 (17%) of 107 patients in the endarterectomy group had at least one new DWI lesion detected on post-treatment scans done a median of 1 day after treatment (adjusted odds ratio [OR] 5∙21, 95% CI 2∙78–9∙79; p<0∙0001). At 1 month, there were changes on fluid-attenuated inversion recovery sequences in 28 (33%) of 86 patients in the stenting group and six (8%) of 75 in the endarterectomy group (adjusted OR 5·93, 95% CI 2·25–15·62; p=0·0003). In patients treated at a centre with a policy of using cerebral protection devices, 37 (73%) of 51 in the stenting group and eight (17%) of 46 in the endarterectomy group had at least one new DWI lesion on post-treatment scans (adjusted OR 12·20, 95% CI 4·53–32·84), whereas in those treated at a centre with a policy of unprotected stenting, 25 (34%) of 73 patients in the stenting group and ten (16%) of 61 in the endarterectomy group had new lesions on DWI (adjusted OR 2·70, 1·16–6·24; interaction p=0·019).

Interpretation: About three times more patients in the stenting group than in the endarterectomy group had new ischaemic lesions on DWI on post-treatment scans. The difference in clinical stroke risk in ICSS is therefore unlikely to have been caused by ascertainment bias. Protection devices did not seem to be effective in preventing cerebral ischaemia during stenting. DWI might serve as a surrogate outcome measure in future trials of carotid interventions.

J Neurosurg 112:497–502, 2010. DOI: 10.3171/2009.7.JNS09572

With the expanding indications and increasing number of patients undergoing deep brain stimulation (DBS), postoperative MR imaging is becoming even more important in guiding clinical care and practice-based learning; important safety concerns have recently emerged, however. Although phantom model studies have driven conservative recommendations regarding imaging parameters, highlighted by 2 recent reports describing adverse neurological events associated with MR imaging in patients with implanted DBS systems, the risks of MR imaging in such patients in clinical practice has not been well addressed. In this study, the authors capitalized on their large experience with serial MR imaging (3 times per patient) to use MR imaging itself and clinical outcomes to examine the safety of MR imaging in patients who underwent staged implantation of DBS electrodes for Parkinson disease, tremor, and dystonia.

Methods. Sixty-four patients underwent staged bilateral lead implantations between 1997 and 2006, and each patient underwent 3 separate MR imaging sessions subsequent to DBS placement. The first of these was performed after the first DBS placement, the second occurred prior to the second DBS placement, and third was after the second DBS placement. Follow-up was conducted to examine adverse events related either to MR imaging or to DBSinduced injury.

Results. One hundred and ninety-two MR images were obtained, and the mean follow-up time was 3.67 years. The average time between the first and second, and second and third MR imaging sessions was 19.4 months and 14.7 hours, respectively. Twenty-two MR imaging–detected new findings of hemorrhage were documented. However, all new findings were related to acute DBS insertion, whereas there were no new findings after imaging of the chronically implanted electrode.

Conclusions. Although potential risks of MR imaging in patients undergoing DBS may be linked to excessive heating, induced electrical currents, disruption of the normal operation of the device, and/or magnetic field interactions, MR imaging can be performed safely in these patients and provides useful information on DBS lead location to inform patient-specific programming and practice-based learning

Journal of Neurosurgery: Spine. March 2010.DOI: 10.3171/2009.9.SPINE09261

DOI: 10.1227/01.NEU.0000365364.87303.AC

OBJECTIVE: The objective of this study was to determine cognitive functioning and health related quality of life one year after aneurysmal subarachnoid hemorrhage in preoperative comatose patients.

METHODS: Patients were investigated for one year using a comprehensive neuropsychological test battery and two HRQOL questionnaires.

RESULTS: Thirty-five of 70 patients survived the bleed, and 26 underwent neuropsychological testing. Two distinct patient groups emerged; one (n = 14) with good cognitive function, and the other (n = 12) with poor cognitive and motor function. Patients performing poorly were older (p = 0.04), had fewer years of education, (p = 0.005) larger preoperative ventricular scores, and were more often shunted (p = 0.02). There were also differences between the two groups in the Glasgow Outcome Scale (p = 0.001), modified Rankin Scale (p = 0.001), and employment status. HRQOL was more reduced in patients with poor cognitive function.

CONCLUSION: A high fraction of survivors among preoperative comatose aneurysmal SAH patients (Hunt and Hess grade V patients) recover to a good physical and cognitive function.

J Neurosurg 112:345–353, 2010.(DOI: 10.3171/2009.6.JNS09223)

Object. An important complication of external CSF drainage is bacterial meningitis or ventriculitis, resulting in increased morbidity, mortality, and health care costs. In 2003, a high rate (37%) of probable drain-related infections was identified at the authors’ hospital. A multidisciplinary working group was installed to reduce this incidence to < 10% within 1.5 years.

Methods. An intervention strategy based on 5 pillars (increased awareness, focused standard operating procedures, a diagnostic and therapeutic algorithm, timely administration of prophylaxis, and improvement of the drainage system) was designed and implemented from 2004 to 2006. During this period all patients with external CSF drainage were prospectively monitored.

Results. Between 2004 and 2006, there were 467 patients in whom 579 drains (external ventricular and exter- nal lumbar) had been placed. The overall incidence of drain-related infections was 16.2% in 2004, 8.9% in 2005, and 11.3% in 2006. For external lumbar drains the number of infections per 100 drain days was 2.4 in 2004, 0.6 in 2005, and 0.8 in 2006. For external ventricular drains these rates were 1.7, 1.0, and 1.2, respectively. Meanwhile, the causative noncutaneous microorganisms, indicative for systemic-contamination during manipulation, decreased. By retrospective analysis, the proportion of patients with a probable drain-related infection decreased from 37% in 2003 to 9% in 2005 and 2006.

Conclusions. The authors’ multidisciplinary approach in which different preventive measures were combined was associated with a significant reduction in the incidence of drain-related secondary meningitis, and thus provides an important improvement of patient safety.