Evaluating the use of prolonged video-EEG monitoring to assess future seizure risk and fitness to drive

ObjectiveThe use of prolonged video-electroencephalography monitoring (VEM), rather than routine electroencephalography (EEG), in predicting the risk of future seizures in patients with epilepsy is not well studied. A longer period of monitoring could be more likely to capture either ictal or interictal epileptiform activity. This information may better assist clinical decision making on driving fitness. The goal of this study was to evaluate the use of 6-hour prolonged VEM versus routine EEG in the assessment of future seizure risk and driving fitness for patients with epilepsy.MethodsData on consecutive patients referred for 6-hour prolonged VEM were retrospectively analyzed. Criteria were developed that combined EEG findings and clinical factors to determine each patient's fitness to drive. Seizure relapse outcomes were followed over 2 years.ResultsOf 34 patients, 27 were considered safe to drive following prolonged VEM. Five (19%) of these 27 patients had seizure relapses; all had an obvious precipitant(s) identified including sleep deprivation, excessive alcohol, and missed medication doses. Seven of the 34 patients were deemed unsafe to drive. All seven (100%) had seizure relapses, with unprovoked seizures in four patients. The relative risk of seizure in patients deemed unfit to drive was 5.4 (P = 0.00015). If only the routine EEG component of the recordings were used with the criteria, the relative risk would have been 3.4 (P = 0.037), with nearly double the number of active drivers having seizures. The majority of patients (76%) in this study had idiopathic generalized epilepsy, with a relative seizure risk of 4.0 (P = 0.002) for patients deemed unfit to drive in this subgroup. The focal epilepsy group was small (eight patients) and did not quite achieve statistical significance.ConclusionSix-hour VEM improves the evaluation of driving fitness by better predicting the risk of subsequent seizure relapse for idiopathic generalized epilepsy and possibly focal epilepsy. Prolonged monitoring is superior to routine EEG. Ongoing avoidance of seizure-provoking factors remains paramount to driving safety.     

Disobedience and driving in patients with epilepsy

ObjectiveMotor vehicle accidents direct legislators to ensure pubic safety. We attempted to characterize and quantify driving risk in patients with seizures (PWS).MethodsWe delivered 12-question surveys to 287 consecutive PWS at an epilepsy clinic in Florida. Illegal and disobedient driving practices were analyzed.ResultsEighty-three of 236 (35.2%) PWS were eligible to drive and 62.3% were ineligible with a seizure in < 6 months (P < 0.001, 95% CI: 0.57–0.70). Among the ineligible responders, 23.8% (35/147) of ineligible responders were illegally driving (14.83% of cohort); 11.86% (28/236) of PWS were disobedient refusing to obey the law, and 8.9% (21/236) of PWS were defiant and knew the law. Sadness (75/236, 31.8%) was the most common reaction to restriction, but disobedient PWS were angry (10/28, 35.7%).ConclusionOverall, a small number of PWS are disobedient and illegally driving. A targeted approach to high-risk drivers with repeated verbal and supplemental driving information may help avoid unnecessary universal physician reporting for PWS.     

Drivers with parkinson's disease: Who participates in research studies?

BackgroundConcern about the effects of Parkinson's disease (PD) on driving competence has precipitated many studies, although most have consisted of small samples. Findings are difficult to interpret and compare as researchers have employed different inclusion/exclusion criteria and rarely provide information on the number of PD patients who are no longer driving, fail to meet other criteria, or refuse to participate.MethodsThe present study examined barriers to participation and representativeness of research participants by screening PD patients at a movement disorder research center to develop a profile of patients who were currently driving versus those who had stopped driving, and to ascertain eligibility and willingness to participate in driving research.ResultsOver 13 months, 128 PD patients were screened (mean age 69.2 ± 10.1; range 39–90); 62% men; with UPDRS motor scores ranging from 8.5 to 68 (mean 30.3 ± 11.3). Only 66% were still driving, and compared to those who had stopped driving, current drivers were more likely to be men (p < .05), younger (p < .05), experienced less severe motor dysfunction (p < .001) and were less likely to report freezing symptoms (p < .05). Less than half (48%) who were eligible for the study agreed to participate. The primary reasons for refusal was having their driving assessed and fear of being reported to licensing authorities.ConclusionsRecruitment of women and participants from various ethnic, educational and socioeconomic backgrounds are important when considering the generalizability of study findings and are needed to develop fitness to drive guidelines in persons with PD.     

Impact of experimentally manipulated sleep on adolescent simulated driving

Objective/BackgroundSleep restriction (SR) impairs adolescents' attention, which could contribute to high rates of driving crashes. Here, we examine the impact of experimental SR on adolescent drivers, considering whether that impact is moderated by the nature of the drive (urban/suburban vs. rural) or how vulnerable each adolescent is to attentional decline after SR.Participants/MethodsA total of 17 healthy 16–18-year-old licensed drivers completed two five-night sleep conditions: SR (6.5 h in bed) versus extended sleep (ES; 10 h in bed) in counterbalanced order. After each, participants completed rural and urban/suburban courses in a driving simulator, and parents rated participants' attention in day-to-day settings. Vulnerability to SR was computed as cross-condition change in parent ratings. Dependent variables included standard deviation (SD) of lateral lane position (SDLP), mean speed, SD of speed, and crashes. Multivariate models examined the main and interaction effects of sleep condition, driving environment, and vulnerability to SR, covarying for years licensed.ResultsAlthough the effects for the other outcomes were nonsignificant, there were three-way interactions (sleep × drive × vulnerability) for mean speed and SDLP (p <0.02). During the rural drive, adolescents had less consistent lateral vehicle control in SR than ES, despite slower driving among those reported to be vulnerable to SR. During the urban/suburban drive, SR worsened SDLP only among adolescents reported to be vulnerable to SR.ConclusionsThese preliminary findings suggest that even a moderate degree of SR may be a modifiable contributor to adolescent driving problems for some. This impact is widely present during monotonous rural drives and in a subgroup during interesting urban/suburban drives.     

Self-reported functional outcome after surgical intervention in patients with idiopathic normal pressure hydrocephalus

The goal of this study was to characterize long-term social and functional outcomes in adults treated for idiopathic normal pressure hydrocephalus (NPH). Data for 252 patients treated medically or surgically for idiopathic NPH were obtained through the Hydrocephalus Association Database Project. Data on post-surgical outcomes including improvement in symptoms, the need for in-home care, ability to drive, and employment status were analyzed. Most patients (73.7%) surveyed were treated with a shunt, an endoscopic third ventriculostomy (ETV), or both. More patients who underwent surgery reported driving and being employed compared to those who did not have surgery. Most shunt patients had improvements in gait (81.1%), urinary incontinence (55.9%), and dementia (64.4%). Overall, shunt patients reported more dramatic improvements in quality of life as compared to ETV patients (72.2% versus 55.6%). Treating idiopathic NPH with cerebrospinal fluid diversion facilitates a return to independence through improved functional and social outcomes.     

Understanding variability in driving recommendations for patients with seizures

BackgroundThere is lack of consensus regarding driving restrictions for patients with epilepsy. Regulations vary by state. New York State (NYS) recommends driving restrictions for one year in a person with an episode of loss of consciousness (LOC), with physician discretion. Often, providers make recommendations to permit their patients to drive after a shorter seizure-free period than proposed guidelines. The prevalence and reasons behind more lenient recommendations have not been elucidated.MethodsForty-one neurologists were surveyed anonymously in Nassau County, New York. They were questioned about the length of recommended driving restrictions (≤ 1, 3, 6, or ≥ 12 months) that they typically provide to patients with suspected seizures in different clinical scenarios and overall reasons for doing so. Data about level of training, setting of practice, use of antiepileptic drug (AED) levels, and electroencephalogram (EEG) were also collected.ResultsOf the 41 neurologists surveyed, 72% reported recommending driving restrictions < 12 months for patients who experienced LOC, without a confirmed diagnosis of seizure. The majority also recommended driving restriction of < 12 months for other scenarios including acute symptomatic seizure, exclusively simple partial seizures, nocturnal seizures, psychogenic nonepileptic seizures (PNES), and seizures occurring with or during AED reduction. The most common rationale was to improve patient autonomy and independence. Less than a third of neurologists estimated that the majority of their patients were noncompliant with driving recommendations.ConclusionWe found that many neurologists' recommendations for limiting driving for patients with seizure-related episodes are shorter than those recommended by NYS. Furthermore, as there are no specific guidelines for questionable epileptic scenarios and seizures occurring nocturnally or without LOC, this appears to contribute to substantial variability in the duration of recommended driving restrictions. This opens a broad discussion about approaches towards advising driving limitations in order to protect public and patient safety while maintaining patient autonomy.     

Socio-demographic factors and their impact on the number of resections for patients with recurrent glioblastoma

Glioblastoma multiforme (GBM) is the most aggressive malignant brain tumour. Having a second or subsequent operation at recurrence may be a positive prognostic factor for survival. Recent studies suggest that socio-demographic variables may influence survival, raising the question whether surgical care differs based on these variables. We examined the relationship between selected socio-demographic variables and the number of repeat operations undergone by patients with recurrent GBM. Data from all patients diagnosed with GBM between 2001 and 2011 was obtained from a clinical database maintained across two institutions (one public, one private). The clinical and socio-demographic factors for patients who received one operation were compared to those who had two or more operations, using chi-squared analyses to determine statistical differences between groups. Socioeconomic status was measured using the Index of Relative Socioeconomic Advantage and Disadvantage scores. Of 553 patients, 449 (81%) had one operation and 104 (19%) had ?2 operations. Patients who had ?2 operations were significantly younger (median 55 years versus 64 years, p < 0.001), less likely to have multifocal (p = 0.043) or bilateral (p = 0.037) disease and more likely to have initial macroscopic resection (p = 0.006), than those who had only one operation. Socioeconomic status did not significantly differ between the groups (p = 0.31). Similarly, there was no significant difference between the number of operations in patients from regional versus city residence and public versus private hospital. This is reassuring as it suggests similar surgical management options are available for patients regardless of socio-demographic background.     

Epileptic seizures at the wheel: An 11-year experience

Over a period of 11 years, patients who suffered an epileptic seizure while driving a motor vehicle were prospectively identified from a private neurology clinic. There were 34 such patients, 23 of whom were male, and the mean age was 33.3 years. Twenty-one of the patients (62%) had complex partial seizures with or without secondary generalization, and 13 (38%) had primary generalized epilepsy. Twenty-seven of the patients (79%) had sustained at least one seizure in the 2 years prior to the driving incident, 24 (71%) within the previous year. Eleven of the patients (32%) were driving despite experiencing at least one seizure per month. Six patients continued to drive despite involvement in multiple accidents. There were two instances of serious personal injury, four instances of minor personal injury, and 21 instances of vehicle or property damage, generally of a minor degree. Seizures while driving are not uncommon. Reasonable and realistic guidelines for traffic safety can be offered in order to encourage a responsible attitude to seizure control in the majority of patients.     

Microvascular decompression for elderly patients with trigeminal neuralgia

Microvascular decompression (MVD) has been demonstrated to be an excellent surgical treatment approach in younger patients with trigeminal neuralgia (TN). However, it is not clear whether there are additional morbidity and mortality risks for MVD in the elderly population. We performed a systematic literature review using six electronic databases for studies that compared outcomes for MVD for TN in elderly (cut-off ⩾60, 65, 70 years) versus younger populations. Outcomes examined included success rate, deaths, strokes, thromboembolism, meningitis, cranial nerve deficits and cerebrospinal fluid leaks. There were 1524 patients in the elderly cohort and 3488 patients in the younger cohort. There was no significant difference in success rates in elderly versus younger patients (87.5% versus 84.8%; P = 0.47). However, recurrence rates were lower in the elderly (11.9% versus 15.6%; P = 0.03). The number of deaths in the elderly cohort was higher (0.9% versus 0.1%; P = 0.003). Rates of stroke (2.5% versus 1%) and thromboembolism (1.1% versus 0%) were also higher for elderly TN patients. No differences were found for rates of meningitis, cranial nerve deficits or cerebrospinal fluid leak. MVD remains an effective and reasonable strategy in the elderly population. There is evidence to suggest that rates of complications such as death, stroke, and thromboembolism may be significantly higher in the elderly population. The presented results may be useful in the decision-making process for MVD in elderly patients with TN.     

Visual vigilance in drivers with obstructive sleep apnea

Objective

To determine the effects of obstructive sleep apnea (OSA) on visual vigilance during simulated automobile driving.

Methods

Twenty-five drivers with OSA and 41 comparison drivers participated in an hour-long drive in a high-fidelity driving simulator. Drivers responded to light targets flashed at seven locations across the forward horizon. Dependent measures were percent correct [hit rate (HR)] and reaction time (RT). Self-assessment of sleepiness used the Stanford Sleepiness Scale (SSS) before and after the drive and the Epworth Sleepiness Scale (ESS).

Results

OSA drivers showed reduced vigilance based on lower HR than comparison drivers, especially for peripheral targets (80.7±14.8% vs. 86.7±8.8%, P=.03). OSA drivers were sleepier at the end of the drive than comparison drivers (SSS=4.2±1.2 vs. 3.6±1.2, P=.03), and increased sleepiness correlated with decreased HR only in those with OSA (r=−0.49, P=.01). Lower HR and higher post-drive SSS predicted greater numbers of driving errors in all subjects. Yet, ESS, predrive SSS, and most objective measures of disease severity failed to predict driving and vigilance performance in OSA.

Conclusions

Reduced vigilance for peripheral visual targets indicates that OSA drivers have restriction of their effective field of view, which may partly explain their increased crash risk. This fatigue-related decline in attention is predicted by increased subjective sleepiness during driving. These findings may suggest a means of identifying and counseling high-risk drivers and aid in the development of in-vehicle alerting and warning devices.     

Fitness to drive with neurological disabilities

To restore the ability to drive is one aim of the rehabilitation of patients with neurological disabilities. In some instances, an evaluation is required to judge a patient's fitness to drive in today's traffic. Forty-three patients of the neurorehabilitation unit of the Valens Clinic were assessed by a standard traffic psychological test protocol and a control drive. In 88%, there was agreement between the judgments based on each procedure. Four patients had failed either the psychological tests or the control drive but not both. Six patients had failed the psychological test and the control drive. Two drove nevertheless, and three patients stopped driving. Nineteen of 32 patients cleared to drive were followed up. Eleven drove without accidents or traffic fines. The traffic psychological tests and control drive yield complementary information on the fitness to drive. However, the assessments need to be improved. New generations of interactive driving simulators may refine the fitness to drive evaluation and become useful tools in driving rehabilitation.     

Attitudes towards epilepsy surgery: A nationwide survey among Swedish neurologists

PurposeEpilepsy surgery is safe and effective for epilepsy that is refractory to medical treatment. However, only a minority of candidates for epilepsy surgery are referred for surgical evaluation. We investigated Swedish neurologists’ views on and criteria for referral for epilepsy surgery.Materials and methodsA survey was sent out to neurologists who treat patients with epilepsy. We received responses from 81% of referring hospitals and 57% of private practices.ResultsSixty-one percent of respondents considered that epilepsy surgery reduced seizure frequency and 53% that it improved quality of life. Surgical treatment was thought to be cost-effective by 90% of respondents. Referral for surgery was considered if three or more antiepileptic drugs had failed. Seizure frequency and severity and, the patient's own wishes were regarded as the most important criteria for surgical referral. MRI and EEG findings were also important whereas duration of illness was considered less important. Age below 65 years and lack of mental retardation were important for considering referral.ConclusionIn general Swedish neurologists have a cautious but positive attitude towards epilepsy surgery. Uncertainties about eligibility criteria among referring clinicians may contribute to the underutilization of epilepsy surgery.     

Outcomes of single-level cervical disc arthroplasty versus anterior cervical discectomy and fusion

Several studies have established the short-term safety and efficacy of cervical disc arthroplasty (CDA) as compared to anterior cervical discectomy and fusion (ACDF). However, few single-center comparative trials have been performed, and current studies do not contain large numbers of patients. We retrospectively reviewed all patients from a single military tertiary medical center between August 2008 to August 2012 who underwent single-level CDA or single-level ACDF and compared their clinical outcomes and complications. A total of 259 consecutive patients were included in the study, 171 patients in the CDA group with an average follow-up of 9.8 (±9.9) months and 88 patients in the ACDF group with an average follow-up of 11.8 (±9.6) months. Relief of pre-operative symptoms was 90.1% in the CDA group and 86.4% in the ACDF group with rates of return to full pre-operative activity of 93.0% and 88.6%, respectively. Patients who underwent CDA had a higher rate of persistent posterior neck pain (15.8% versus 12.5%), and patients who underwent ACDF were at risk for symptomatic pseudarthrosis at a rate of 3.4%. Reoperation rates were higher in the ACDF group (5.7% versus 3.5%). To our knowledge, this review is the largest, non-funded, comparison study between single-level CDA and single-level ACDF. This study demonstrates that CDA is a safe and reliable alternative to ACDF in the treatment of cervical radiculopathy and myelopathy resulting from spondylosis and acute disc herniation.     

Individual state driving restrictions for people with epilepsy in the US.

BACKGROUND: States in the United States vary widely in their approaches to restricting driving for patients with epilepsy. Many states have shortened seizure-free restrictions or have adopted flexible regulations that consider individual clinical factors in determining driving privileges. The authors summarized state driving restrictions for patients with seizures, particularly unpublished regulatory practices, and determined the role and liability of physicians in judging driving safety for patients with epilepsy. METHODS: The authors surveyed motor vehicle administration bureaus in the 50 states and the District of Columbia and compared the laws, regulations, and practices restricting driving for people with epilepsy. Key responses from a questionnaire were confirmed by state motor vehicle administrations with phone interviews and by a signed executive summary. RESULTS: Twenty-eight states, including the District of Columbia, have laws requiring patients with epilepsy to be free of seizures for single fixed periods, with a median restriction of six months (range, 3 to 12 months). Twenty-three states have adopted more flexible approaches to restricting driving, such as varying seizure-free restrictions based on individual clinical factors. Many states allow patients to drive after shorter seizure-free periods than stated in their laws. These practices, however, are usually unpublished and not easily accessible. Physicians helped determine when their patients may drive in 13 states and were not legally shielded for their assessments in six of these states. CONCLUSIONS: States vary widely in how they regulate driving for patients with seizures. These varied regulatory approaches present potentially valuable models to determine how driving might be best regulated to protect public and patient safety optimally while permitting patients with controlled seizures to drive.     

Seizures occurring while driving in patients with and without diagnosis of epilepsy: Frequency and association with automobile accidents

Seizure may occur during any human activity, including driving. The objectives of this study were to report the frequency of seizure occurring while driving, clarify patient characteristics and analyze the behavioral patterns of drivers afflicted by seizure. A single-center, retrospective study was conducted using prospectively acquired data. Data of 658 adult seizure patients who visited our emergency department between January 2011 and December 2016 were used for analysis, focusing on daily activities immediately before seizure. Nineteen of the 658 patients (2.9%) sustained seizure while driving. The 658 patients were dichotomized on the basis of whether he or she had been diagnosed with epileptic seizure (ES). Seven of the 307 patients with ES vs. 12 of the 351 patients without ES sustained seizure while driving. The frequencies did not differ significantly between the two groups (2.3% vs. 3.4%, p = 0.49). Structural lesions on brain imaging studies were found in 6 of the 12 patients without ES (50%). Sixteen of the 19 patients (84%) caused automobile accidents after seizure. Among the 7 patients with ES, antiepileptic drugs had not been prescribed in 3 (43%). Although seizures occurring while driving have been studied extensively, most researchers focused on patients with ES. This study was unique because it focused on patients without ES, and the current findings that seizures in patients without ES outnumbered seizures in those with ES may be informative to clinical neuroscientists and emergency physicians. Prospective studies are expected to identify individuals at risk for first seizure occurring while driving.     

Concurrent neoadjuvant chemotherapy is an independent risk factor of stroke,all-cause morbidity,and mortality in patients undergoing brain tumor resection

Neoadjuvant chemotherapy (NC) may be utilized for treatment of various tumors, and a proportion of patients on active NC may require resection of a primary or secondary brain tumor. The objective of this study is to examine the impact of NC on postoperative neurosurgical outcomes. Elective cranial neurosurgical patient data was obtained from the American College of Surgeons National Surgical Quality Improvement Program database between 2006 and 2012. The impact of NC on 30 day stroke, all-cause postoperative morbidity, and mortality were assessed. Adjusted odds ratios (OR) were estimated for stroke, overall morbidity, and mortality using a multivariable logistic regression model, accomplished in stepwise fashion, for patients receiving NC versus those not receiving NC. This study analyzed 3812 patients undergoing elective cranial surgery, with 152 on concurrent NC. NC patients had a complication rate of 23.68%, while patients not receiving NC had a lower complication rate at 17.65% (p = 0.057). Multivariable regression analysis revealed that patients who received NC had significantly increased odds of developing a stroke with neurological deficit (OR 3.39; 95% confidence interval [CI] 1.37–8.40) and all-cause postoperative morbidity (OR 1.57; 95% CI 1.04–2.37) over the control group. Finally, the NC cohort demonstrated higher odds of mortality following surgery than their non-NC counterparts (OR 3.81; 95% CI 1.81–8.02). Ninety-two patients (2.41%) died within 30 days, of whom 10 (6.58%) were receiving NC versus 82 non-NC (2.24%) patients (p = 0.001). Concurrent NC is associated with an increased risk of short-term stroke with neurological deficit, all-cause morbidity, and mortality in patients undergoing brain tumor resection.     

Risk factors for unfavorable clinical outcome in patients with documented heparin-induced thrombocytopenia

Background

Prognostic factors for unfavorable clinical outcome in patients with heparin-induced thrombocytopenia (HIT) are largely unknown.

Design and methods

In this multicenter, retrospective, case-control study, all HIT patients were treated with danaparoid. Study cases were HIT patients with an unfavorable clinical outcome. Controls were HIT patients who were not study cases. Unfavorable clinical outcome was defined as the occurrence of at least one of the following clinical events: death within 60 days after HIT start date, or venous or arterial thromboembolism, amputation, major bleeding, or disseminated intra-vascular coagulation between 48 hours and 60 days after HIT start date.

Results

Compared with controls (n = 65), thrombotic episodes within 48 hours of HIT start date were more frequent (59.2% versus 32.3%; p = 0.004), the median time between HIT start date and initiation of danaparoid infusion was longer (3.0 versus 1.0 days; p = 0.001), and this treatment was more frequently underdosed (43.8% versus 18.8%; p = 0.004) in study cases (n = 49). Upon multivariate analysis, all these three parameters were significant predictive factors for unfavorable clinical outcome. The adjusted odds ratios [95% confidence interval] were 6.6 [2.5-17.3] for time between HIT start date and danaparoid initiation over 48 hours, 4.3 [1.5-12.0] for danaparoid underdosing, and 3.2 [1.3-8.0] for presence of a thromboembolic episode at HIT start date.

Conclusions

This study supports the recommendations concerning the management of HIT patients, namely discontinuation of all heparin administration once the diagnosis is suspected and prompt initiation of an alternative anticoagulant drug with a strict adherence to doses specifically recommended for these patients.     

Efficacy of antibiotic-impregnated external ventricular drains in reducing ventriculostomy-associated infections

Use of an external ventricular drain (EVD) is essential for managing patients with hydrocephalus or intracranial hypertension. While this procedure is safe and efficacious, ventriculostomy-associated infections (VAI) continue to cause significant morbidity. In this study, we evaluated the efficacy of antibiotic-coated EVD (AC-EVD) in reducing the occurrence of VAI. Between July 2007 and July 2009, 203 patients underwent placement of an EVD. A total of 145 of these patients met the inclusion criteria, with 76 patients (52.4%) receiving AC-EVD and 69 patients (47.6%) receiving uncoated EVD. Ten patients (6.9%) developed VAI, of whom three were in the AC-EVD group and seven were in the uncoated EVD group (p = 0.19). The mean duration between catheter insertion and positive cerebrospinal fluid culture was significantly greater in the AC-EVD group versus the uncoated EVD group (15 ± 4 days versus 4 ± 2 days, respectively; p = 0.001). In the uncoated EVD group, 17 of 69 patients (24.6%) were dead at 3 years versus 12 of 76 (15.8%) patients in the AC-EVD group (p = 0.21). The overall VAI rate was 6.9% with a trend toward lower infection rates in the AC-EVD group compared to the uncoated EVD group (3.9% versus 10.1%, respectively; p > 0.05).     

Evaluation of cerebrovascular reserve using xenon-enhanced CT scanning in patients with symptomatic middle cerebral artery stenosis

Cerebrovascular reserve (CVR) is an important prognostic factor in patients with major cerebral arterial steno-occlusive disease. However, few studies have examined CVR in symptomatic intracranial stenosis without ipsilateral extracranial internal carotid artery stenosis. This study sought to evaluate CVR in patients with symptomatic middle cerebral artery (MCA) stenosis using xenon-enhanced computed tomography (Xe/CT) with acetazolamide (ACZ) challenge. Twelve patients with symptomatic MCA stenosis were recruited. All patients were examined by Xe/CT to quantitatively measure resting cerebral blood flow (CBF) and received ACZ challenge to evaluate CVR. For resting CBF, no significant differences were found between the sides in four regions of interest. After the ACZ challenge test, the CVR was significantly different between hemispheres (ipsilateral versus contralateral CVR: 12.9 ± 24.3% versus 28.0 ± 16.8%, respectively; p = 0.005) and in the MCA territory (ipsilateral versus contralateral CVR: 8.7 ± 24.7% versus 29.3 ± 24%, respectively; p = 0.003). However, no significant differences in CVR were detected between cortical comparisons and white matter comparisons from the two sides. Thus, ACZ-challenge Xe/CT is useful for the measurement of CBF and CVR in these patients. Impaired CVR is an important characteristic of patients with symptomatic MCA stenosis.     

Perioperative complications in open versus percutaneous treatment of spinal fractures in patients with an ankylosed spine

We compared open stabilization of vertebral fractures to percutaneous spinal fixation techniques in patients with a diagnosis of either ankylosing spondylitis (AS) or diffuse idiopathic skeletal hyperostosis (DISH). A retrospective review of patients known to have AS or DISH treated for spinal column fracture at a single institution between 1995 and 2011 was performed. Patients were analyzed by the type of fixation, divided into either a percutaneous group (PG) or an open group (OG). There were 41 patients identified with a spinal column fracture and history of AS or DISH who received surgical intervention. There were 17 (42%) patients with AS and 24 (58%) with DISH. Patients in the PG and OG cohorts presented with similar mechanisms of injury, Injury Severity Scale, number of vertebral fractures, number of additional injuries, and Arbeitsgemeinschaft für Osteosynthesefragen (AO) classification scores. Mean operative time (254.76 minutes versus 334.67 minutes, p = 0.040), estimated blood loss (166.8 versus 1240.36 mL, p < 0.001), blood transfusion volume (178.32 versus 848.69 mL, p < 0.001), and time to discharge (9.58 days versus 16.73 days, p = 0.008) were significantly less in the PG cohort. The rate of blood transfusion (36% versus 87.5%, p = 0.001) and complications (56% versus 87%, p = 0.045) were significantly less in the PG cohort. Percutaneous stabilization of fractures in patients with AS or DISH was associated with lower blood loss, shorter operative times and decreased need for transfusion, shorter hospitalization time and a lower perioperative complication rate.