Validation of the modified radiosurgery-based arteriovenous malformation score in a linear accelerator radiosurgery experience in Hong Kong.

The modified radiosurgery-based arteriovenous malformation (AVM) score (modified AVM score or Pollock-Flickinger AVM score [PFAS]) is a simplified grading system developed to predict outcome after gamma knife radiosurgery for cerebral AVM. The purpose of this study was to test the PFAS in a cohort of patients managed with linear accelerator (LINAC) radiosurgery. We analyzed 70 consecutive patients with cerebral AVM treated with LINAC radiosurgery in Hong Kong. The scores were determined by the following equation: Modified AVM score=(0.1×volume [cm(3)])+(0.02×age [years])+(0.5×location). The location values are as follows: hemispheric/corpus callosum/cerebellar=0; basal ganglia/thalamus/brainstem=1. A total of 74% of patients presented with ruptured AVM before radiosurgery. The overall obliteration rate was 86%. Five (7%) patients developed new permanent neurological deficits from delayed bleeding or radiation-induced complications. Modified AVM score correlated with the percentage of patients with AVM obliteration without new neurological deficits (≤1, 96%; 1.01-1.50, 78%; 1.51-2.00, 90%; >2, 50%; Spearman's rho 0.354, p=0.003). In conclusion, the modified AVM score is a good predictor of patient outcome after LINAC radiosurgery in our cohort. The modified AVM score can be used to guide treatment selection for cerebral AVM and stratify patients for future comparative analyses.

Changes of cognitive functioning following mild traumatic brain injury over a 3-month period.

PRIMARY OBJECTIVE: To examine the cognitive functioning in patients with complicated mild traumatic brain injury immediately post-injury and at 1 and 3 months post-injury. RESEARCH DESIGN, METHODS, AND PROCEDURES: Between-group comparisons were adopted for this study. Specifically, both patients and healthy controls were administered neuropsychological assessments measuring attention, memory and executive functions at three time points. RESULTS: Findings indicate that patients performed significantly more poorly in information processing and divided attention, sustained attention, verbal recognition and verbal fluency immediately post-injury. While the information processing and divided attention of mild TBI patients improved at 1 month and returned to normal at 3 months post-injury, their sustained attention remained significantly poorer over the 3-month period. CONCLUSIONS: Findings suggest that attention dysfunction is noticeable immediately following a mild TBI. Different attention functions appear to recover at a different pace over time, suggesting that the condition may have a differential impact on the different sub-types of attention.

Bryan artificial cervical disc arthroplasty in a patient with Klippel-Feil syndrome.

Technological advances have made more options available for surgical intervention in spinal disorders. From spinal fusion to artificial disc implantation, these advancements have brought great benefits, allowing preservation of spinal motion and flexibility after intervertebral discectomy. Yet the use of artificial discs as a treatment for congenital spinal disorders has been documented in only a handful of publications. We report a case where a Bryan artificial cervical disc arthroplasty was used to maintain and preserve the mobility and function of the cervical motion segments adjacent to fused vertebral lesions in a 33-year-old woman with Klippel-Feil syndrome who presented with chronic neck pain and signs of early myelopathy. The rationales for using the Bryan disc prosthesis system in patients with Klippel-Feil syndrome and its advantages over conventional surgical interventions are discussed.

The comparative impact of video consultation on emergency neurosurgical referrals.

OBJECTIVE: Neurosurgical resources are concentrated in tertiary referral centers, whereas emergencies identified from district general hospitals are traditionally referred by telephone consultation (TC). Recent advances in communication technology offer the alternative options of teleradiology (TR) and video consultation (VC). This study aimed to determine the differences among these three consultation methods on the basis of their process-of-care indicators, clinical outcomes, and cost-effectiveness. METHODS: Patients with emergency neurosurgical conditions (head injury, stroke, and miscellaneous) from a district general hospital were randomized to three different modes of consultation: TC, TR, or VC. Process-of-care indicators (postresuscitation Glasgow Coma Scale score, consultation time required, diagnostic accuracy, and transfer decision and safety), 6-month clinical outcome, and cost-effectiveness of the three consultation modes were correlated. RESULTS: In a 3-year period, 710 patients were recruited and randomized to the three consultation modes (n = 235, 239, and 236, respectively). Demographic and clinical data were comparable. TR and VC showed a definite advantage in diagnostic accuracy over TC (89.1 and 87.7% versus 63.8%; P < 0.001). However, duration of the corresponding consultation process was longer for TR and VC than TC (1.01 and 1.3 h versus 0.70 h). A high failure rate (30%) was noted in VC. Thirty-three percent of patients were transferred to the neurosurgical center after consultation. The difference in consultation modes did not have an impact on transfer rate and safety. There was a trend toward more favorable outcome (61%; P = 0.12) and a reduced mortality (25%; P = 0.025) in TR compared with TC (54 and 34%, respectively) and VC (54 and 33%, respectively). The mean cost per patient in the VC group was slightly higher than the other two groups (TC versus TR versus VC = 14,000 US dollars versus 14,400 US dollars versus 16,300 US dollars, respectively), but the differences were not statistically significant. CONCLUSION: Emergency neurosurgical consultation assisted by TR and VC achieved a higher diagnostic accuracy in comparison with conventional TC. Although VC did not show an advantage over TR in process-of-care indicators, clinical outcome, and cost, it has been proven to be a safe mode of consultation in emergency neurosurgery.

Cervical arthroplasty with the Bryan disc.

Cervical arthroplasty is a promising nonfusion alternative for the treatment of degenerative disc disease. After anterior cervical discectomy for neurological decompression, the intervertebral space is reconstructed by use of a metal and polymer prosthesis, allowing semiconstrained motion in multiple planes. This approach allows for preservation of cervical motion, potentially reducing the risk of transitional-level disease.

Apolipoprotein e genotype and outcome in aneurysmal subarachnoid hemorrhage.

BACKGROUND AND PURPOSE: Active management of ruptured intracranial aneurysm in subarachnoid hemorrhage is indicated in patients with favorable prognosis. Outcome prediction is based on patient characteristics and clinical and radiological factors. Current clinical grading scales are imprecise, with low interobserver reproducibility. Therefore, outcome prediction remains inconsistent and decision making becomes difficult, especially for patients with poor clinical grade. METHODS: The possible relationship between apolipoprotein E genotype and the outcome of patients suffering spontaneous subarachnoid hemorrhage was investigated. A prospective study was conducted on all patients with spontaneous aneurysmal subarachnoid hemorrhage admitted to our unit during a 2-year period. All patients were managed according to standard protocol, and treatments were given according to their clinical grading. Patient characteristics, clinical grade, radiological grade, and apolipoprotein E genotype were documented. The focus of the study was the 6-month neurological outcome for this group of patients after they were discharged. RESULTS: Seventy-two patients with aneurysmal subarachnoid hemorrhage were admitted to the Prince of Wales Hospital in Shatin, Hong Kong, China, from February 1998 to February 2000. Their ages ranged from 24 to 95 years of age, with a mean (SD) age of 58.3 (15.0) years. Apolipoprotein E epsilon4 was found in 15 patients (21%). At 6 months, Glasgow Outcome Scale score < or = 3 was found in 29 patients (40%). Univariate analysis showed that older patients (odds ratio [OR], 1.03; 95% CI, 1.00 to 1.07; P=0.07) and patients with poor Fisher's grade (OR, 4.5; 95% CI, 1.3 to 15.2; P=0.01), poor World Federation of Neurological Surgeons grade (OR, 5.8; 95% CI, 1.9 to 17.8; P=0.002), or apolipoprotein E epsilon4 (OR, 6.0; 95% CI, 1.7 to 21.3; P=0.006) were more likely to attain unfavorable outcome at 6 months. The additional effect of apolipoprotein E epsilon4 remained significant in the multiple logistic regression model (OR, 11.3; 95% CI, 2.2 to 57.0; P=0.003); the gain in predictive performance was not significant (P=0.26). CONCLUSIONS: Apolipoprotein E epsilon4 genotype is related to poor outcome in patients with subarachnoid hemorrhage.