Flashbulb memory recall in healthy adults - a functional magnetic resonance imaging study.

The present study investigated neural activations related to flashbulb memory (FM) recall and examined whether the amygdala and hippocampus are involved in FM recall. 20 healthy adults completed a block design with an FM-condition, where the reception events for a number of potential FM events had to be recalled, and a control condition (FMC) comprising reception events lacking FM characteristics. A definition naming task was used as an implicit baseline. The individual emotional reaction to the FM events (EMO) and self-rated retrieval success were included in the SPM model as modulating parameters. The main contrast of interest were FM > FMC and activations associated with EMO. ROI-analyses on mesiotemporal regions were performed. FM > FMC yielded activations in line with the autobiographical memory network, with mostly left sided-activations. EMO was associated with a more bilateral activation pattern. ROI-analysis revealed activations for EMO in the right amygdala and HATA. FM > FMC was associated with right hippocampal activations. The present findings are compatible with previous research into autobiographical memory, but also show activations for FM recall different from ordinary, not highly emotional autobiographical memories, as EMO is associated with a more bilateral network. Moreover, the amygdala seems to be involved in FM recall.

Management of the neck in T1 and T2 buccal squamous cell carcinoma.

Buccal squamous cell carcinoma (SCC) appears to behave more aggressively than other oral subsites, in particular with regards to regional disease at presentation and regional recurrence. Adequate management of the neck is of the utmost importance but is still the subject of debate. An international multicentre retrospective review of 101 patients treated for T1-T2 buccal SCC was performed. Twenty-four were staged clinical node positive (cN+) and underwent therapeutic neck dissection, while 77 were node negative (cN0), with 32 undergoing elective neck dissection (END), with an occult nodal metastasis rate of 28.1%. Depth of invasion (DOI) < 4 mm was associated with a significantly lower rate of cervical nodal metastasis (87.5% versus 12.5%; P = 0.033). END demonstrated a non-significantly lower regional recurrence rate compared to observation (6.3% versus 8.9%, P = 0.670). Regional recurrence was more common in pN+ (24%) and undissected cases (8.9%) than in pN0 patients (0%) (P = 0.011) and was associated with DOI > 5 mm (P = 0.002). Regional recurrence resulted in a reduction in survival (24 versus 93 months, P < 0.001). In the pT2cN0 group, END improved survival (123 versus 26 months, P = 0.009). It is suggested that END be performed in cT2N0 buccal SCC, particularly for tumours with DOI > 4 mm.

Registration of magnetic resonance and computed tomography images in patients with oral squamous cell carcinoma for three-dimensional virtual planning of mandibular resection and reconstruction.

The aim of this study was to evaluate and present an automated method for registration of magnetic resonance imaging (MRI) and computed tomography (CT) or cone beam CT (CBCT) images of the mandibular region for patients with oral squamous cell carcinoma (OSCC). Registered MRI and (CB)CT could facilitate the three-dimensional virtual planning of surgical guides employed for resection and reconstruction in patients with OSCC with mandibular invasion. MRI and (CB)CT images were collected retrospectively from 19 patients. MRI images were aligned with (CB)CT images employing a rigid registration approach (stage 1), a rigid registration approach using a mandibular mask (stage 2), and two non-rigid registration approaches (stage 3). Registration accuracy was quantified by the mean target registration error (mTRE), calculated over a set of landmarks annotated by two observers. Stage 2 achieved the best registration result, with an mTRE of 2.5±0.7mm, which was comparable to the inter- and intra-observer variabilities of landmark placement in MRI. Stage 2 was significantly better aligned compared to all approaches in stage 3. In conclusion, this study demonstrated that rigid registration with the use of a mask is an appropriate image registration method for aligning MRI and (CB)CT images of the mandibular region in patients with OSCC.

Evaluation of bone resection margins of segmental mandibulectomy for oral squamous cell carcinoma.

Resection margins are frequently studied in patients with oral squamous cell carcinoma and are accepted as a constant prognostic factor. While most evidence is based on soft tissue margins, reported data for bone resection margins are scarce. The aim of this retrospective study was to evaluate and determine the utility of surgical margins in bone resections for oral cavity squamous cell carcinoma (OCSCC). The status of bone resection margins and their impact on survival was investigated in patients who had undergone segmental mandibulectomy for OCSCC. Medical records were retrieved for the years 2000-2012; 127 patients were identified and included in the study. Tumour-positive bone resection margins were found in 21% of the patients. The 5-year overall survival was significantly lower in this group (P<0.005). Therefore, there is a need for intraoperative feedback on the status of bone resection margins to enable immediate additional resection where necessary. Although the lack of intraoperative methods for the evaluation of bone tissue has been addressed by many authors, there is still no reliable method for widespread use. Future research should focus on an objective, accurate, and rapid method of intraoperative assessment for the entire bone resection margin to optimize patient outcomes.

The possible premalignant character of oral lichen planus and oral lichenoid lesions: a prospective five-year follow-up study of 192 patients.

Recently, we reported the preliminary results of a prospective study on the possible premalignant character of oral lichen planus (OLP) and oral lichenoid lesions (OLL). Based on these data it was concluded that there was some but no convincing support for the hypothesis that patients with OLL have an increased risk of development of oral cancer, but not so in patients with OLP. In the present treatise the results of prolonged follow-up of this cohort of patients have been described. A study group of 192 patients, 67 patients diagnosed with OLP and 125 patients with OLL, according to revised World Health Organization diagnostic criteria, was followed for periods ranging from 7.6 to 96.9 months (mean, 55.9 months). The expected number of patients with oral cancer in the group of patients with OLP and in the group of patients with OLL was estimated by comparing the number of patients, their ages, sex, and the length of follow-up to annual incidence rates of oral cancer for the general population in The Netherlands. The binomial test was used to determine whether the observed number of cases of cancer in the OLP group and the OLL group exceeded the expected numbers. Four out of 192 patients, two men and two women, developed a squamous cell carcinoma of the oral mucosa during follow-up. All malignant transformations occurred in the OLL group. The malignant transformation of the OLL group, based on a mean follow-up of 53.8 months, was calculated at 0.71% per year. A comparison of the expected against actual figures for the development of carcinomas revealed no increase in patients with OLP and a 142-fold increase in patients with OLL, the latter being statistically significant, with a p-value of 0.044. The present data give support to the hypothesis that patients with OLL have an increased risk of development of oral cancer. There seems to be no increased risk in patients with OLP. In view of our results we advise to monitor only the subgroup of OLL patients twice a year for early detection of possible malignant transformation.

[A swelling in the midline of the mandible caused by a ossifying fibroma]. / Een zwelling in het onderfront: berustend op een ossificerend fibroom.

A 34-year-old woman complained of a swelling in the midline of the mandible, present for about six months and diagnosed as ossifying fibroma. Because of the rapid development and the extent of the tumour, treatment consisted of a partial mandibulectomy, followed by immediate reconstruction with a free vascularized fibula transplant.

Presurgical MR Imaging in Epilepsy.

Primary goal of magnetic resonance imaging in epilepsy patients is to detect epileptogenic lesions with small lesions best detectable on a 3D FLAIR SPACE sequence with 1 mm(3) voxels. Morphometric analysis of 3D T1-weighted data sets helps to find subtle lesions and may reveal the true extent of a lesion. In further presurgical work-up, language lateralization and spatial relationship of epileptogenic lesions to eloquent cortex and white matter tracts must be evaluated. With clear left lateralization language, fMRI is sufficient; in atypical lateralizations, Wada test and electrical stimulation mapping may be added. Primary motor cortex and corticospinal tract on one and visual cortex and optic radiation on the other side are displayed with fMRI and diffusion tensor tractography. For the corticospinal tract a "global" tracking algorithm, for the optic radiation including Meyer' loop, which may be damaged in anterior temporal lobe resections, a probabilistic algorithm is best suited.

Peripheral hemodialysis shunt with intracranial venous congestion.

BACKGROUND: Intracranial venous congestion is often caused by local venous thrombosis or brain arteriovenous fistulas. Hemodialysis shunts are known to cause venous enlargement in the arm or chest but have not been related to intracranial vascular pathology. Case Description- A 59-year-old woman who presented with increasing headache, gait instability, and memory loss was a renal transplant recipient who still carried a left upper arm shunt. Cranial CT scan showed enlarged veins in the posterior fossa with incipient hydrocephalus. Extracranial duplex sonography revealed reversed flow in the left internal jugular vein, which normalized on cuff inflation around the shunt-carrying arm. The reversed flow, intracranial venous congestion, and neurological status improved after surgical shunt ligation. CONCLUSIONS: To our knowledge, this is the first case description of an intracranial venous outflow obstruction caused by a peripheral arteriovenous shunt.

Dysplastic vessels after surgery for brain arteriovenous malformations.

BACKGROUND AND PURPOSE: The cause and clinical significance of residual dysplastic vessels after surgery for brain arteriovenous malformations (AVM) are unclear. We studied predictors and frequency of residual dysplastic vessels on cerebral angiography after AVM surgery. METHODS: The 240 prospectively enrolled surgical patients from the New York AVM Databank underwent 269 AVM-related surgical procedures. Reported postoperative brain angiographic findings were classified post hoc as showing (1) persistent dysplastic vessels, (2) a residual AVM, (3) focal hyperemia in the surgical bed, (4) other changes, or (5) a normal angiogram. Univariate and multivariate models were applied to test for an association between residual dysplastic vessels and patient age, sex, preoperative AVM size, anatomic AVM location, number of embolization procedures before surgery, and the time interval between AVM surgery and the postoperative angiogram. RESULTS: Of the 224 documented postoperative angiograms, 78 (35%) showed dysplastic vessels, 24 (11%) had evidence for a residual AVM, 16 (7%) showed focal hyperemia, 6 (2%) revealed other findings, and 100 (45%) were normal. The number of cases showing angiographic evidence for dysplastic vessels was significantly associated with increasing size of the AVM (in millimeter increments; P=0.0001); the mean diameter of AVMs in patients showing dysplastic vessels after surgery was significantly larger (41 mm, SD +/-14) than in those without residual dysplastic vessels (27 mm, SD +/-13; P<0.001). Symptomatic postoperative intracerebral hemorrhage occurred in 4 patients (1%), in 2 of whom dysplastic vessels were seen on the postoperative angiogram. CONCLUSIONS: The findings suggest that persistent dysplastic vessels may be found in approximately one third of angiograms after AVM surgery. Preoperative AVM size was found to be an independent predictor for the occurrence of dysplastic vessels on the postoperative angiogram.

Association of infratentorial brain arteriovenous malformations with hemorrhage at initial presentation.

BACKGROUND AND PURPOSE: The goal of this study was to analyze the association of hemorrhagic presentation with infratentorial brain arteriovenous malformations (AVMs). METHODS: The 623 consecutive, prospectively enrolled patients from the Columbia AVM Databank were analyzed in a cross-sectional study. Clinical presentation (diagnostic event) was categorized as intracranial hemorrhage or nonhemorrhagic presentation. From brain imaging and cerebral angiography, AVM location was classified as either infratentorial or supratentorial. Univariate and multivariate statistical models were applied to test the effect of age, sex, AVM size and location, venous drainage pattern, and associated (ie, feeding artery or intranidal) arterial aneurysms on the likelihood of hemorrhage at initial AVM presentation. RESULTS: Of the 623 patients, 72 (12%) had an infratentorial and 551 (88%) had a supratentorial AVM. Intracranial hemorrhage was the presenting symptom in 283 patients (45%), and infratentorial AVM location was significantly more frequent (18%) among patients who bled initially (6%; odds ratio [OR], 3.60; 95% confidence interval [CI], 2.09 to 6.20). This difference remained significant (OR, 1.99; 95% CI, 1.07 to 3.69) in the multivariate logistic regression model controlling for age, sex, AVM size, deep venous drainage, and associated arterial aneurysms. In the same model, the effect of other established determinants for AVM hemorrhage--ie, AVM size (in 1-mm increments; OR, 0.95; 95% CI, 0.94 to 0.96), deep venous drainage (OR, 3.09; 95% CI, 1.87 to 5.12), and associated aneurysms (OR, 2.78; 95% CI, 1.76 to 4.40)--remained significant. CONCLUSIONS: Our findings suggest that infratentorial AVM location is independently associated with hemorrhagic AVM presentation.

The New York Islands AVM Study: design, study progress, and initial results.

BACKGROUND AND PURPOSE: Prospective population-based data on the incidence of brain arteriovenous malformation (AVM) hemorrhage are scarce. We studied lifetime detection rates of brain AVM and incident AVM hemorrhage in a defined population. METHODS: The New York islands (ie, Manhattan Island, Staten Island, and Long Island) comprise a 9,429,541 population according to the 2000 census. Since March 15, 2000, all major New York islands hospitals have prospectively reported data on consecutive patients living in the study area with a diagnosis of brain AVM and whether the patient had suffered AVM hemorrhage. Patients living outside the ZIP code-defined study area were excluded from the study population. RESULTS: As of June 14, 2002, 284 prospective AVM patients (mean+/-SD age, 35+/-18 years; 49% women) were encountered during 21,216,467 person-years of observation, leading to an average annual AVM detection rate of 1.34 per 100,000 person-years (95% CI, 1.18 to 1.49). The incidence of first-ever AVM hemorrhage (n=108; mean age, 31+/-19 years; 45% women) was 0.51 per 100,000 person-years (95% CI, 0.41 to 0.61). The estimated prevalence of AVM hemorrhage among detected cases (n=144; mean age, 33+/-19 years; 50% women) was 0.68 per 100,000 (95% CI, 0.57 to 0.79). CONCLUSIONS: Our prospective data, spanning 27 months, suggest stable rates for AVM detection and incident AVM hemorrhage. Approximately half of AVM patients may suffer intracranial hemorrhage.

Effect of age on clinical and morphological characteristics in patients with brain arteriovenous malformation.

BACKGROUND AND PURPOSE: The goal of this work was to determine the effect of age at initial presentation on clinical and morphological characteristics in patients with brain arteriovenous malformation (AVM). METHODS: The 542 consecutive patients from the prospective Columbia AVM database (mean+/-SD age, 34+/-15 years) were analyzed. Univariate statistical models were used to test the effect of age at initial presentation on clinical (AVM hemorrhage, seizures, headaches, neurological deficit, other/asymptomatic) and morphological (AVM size, venous drainage pattern, AVM brain location, concurrent arterial aneurysms) characteristics. RESULTS: Hemorrhage was the presenting symptom in 46% (n=247); 29% (n=155) presented with seizures, 13% (n=71) with headaches, 7% (n=36) with a neurological deficit, and 6% (n=33) without AVM-related symptoms. Increasing age correlated positively with intracranial hemorrhage (P=0.001), focal neurological deficits (P=0.007), infratentorial AVMs (P<0.001), and concurrent arterial aneurysms (P<0.001); an inverse correlation was found with seizures (P<0.001), AVM size (P=0.001), and lobar (P<0.001), deep (P=0.008), and borderzone (P=0.014) location. No age differences were found for sex, headache, asymptomatic presentation, and venous drainage pattern. CONCLUSIONS: Our data suggest a significant interaction of patient age and clinical and morphological AVM features and argue against uniform AVM characteristics across different age classes at initial presentation. In particular, AVM patients diagnosed at a higher age show a higher fraction of AVM hemorrhage and are more likely to harbor additional risk factors such as concurrent arterial aneurysms and small AVM diameter. Longitudinal population-based AVM data are necessary to confirm these findings.

Determinants of neurological outcome after surgery for brain arteriovenous malformation.

BACKGROUND AND PURPOSE: We sought to define determinants of neurological deficit after surgery for brain arteriovenous malformation (AVM). METHODS: One hundred twenty-four prospective patients (48% women, mean age 33 years) underwent microsurgical brain AVM resection. Patients were examined by 3 study neurologists immediately before surgery, postoperatively in-hospital, by in-person long-term follow-up, and with a structured telephone follow-up. They were classified according to the 5-point Spetzler-Martin grading system, with its 3 elements: size, venous drainage pattern, and location. The functional neurological status was classified with the modified Rankin scale. Multivariate logistic regression models were applied to test the effect of patient age, gender, and the 3 Spetzler-Martin elements on early and long-term postoperative neurological complications. RESULTS: Twelve patients (10%) were classified as Spetzler-Martin grade 1; 36 (29%) as grade 2; 47 (38%) as grade 3; 26 (21%) as grade 4; and 3 (2%) as grade 5. Postoperatively, in-hospital, 51 patients (41%) showed new neurological deficits (15% disabling [ie, Rankin scale score >2] and 26% nondisabling [ie, Rankin 1 or 2]). At long-term follow-up (mean follow-up time 12 months), 47 patients (38%) revealed surgery-related neurological deficits (6% disabling; 32% nondisabling). The rate of neurological complications increased by Spetzler-Martin grade. Female gender, AVM size, and deep venous drainage were significantly associated with neurological deficits at in-hospital and long-term evaluation. For patient age and AVM location, no significant association was found. CONCLUSIONS: The findings suggest that female gender, AVM size, and AVM drainage into the deep venous system may be determinants of neurological deficit after microsurgical AVM resection.

Incident hemorrhage risk of brain arteriovenous malformations located in the arterial borderzones.

BACKGROUND AND PURPOSE: We sought to assess the relative risk of hemorrhagic presentation of brain arteriovenous malformations (AVMs) located in the arterial borderzone territories. METHODS: The 464 consecutive, prospectively enrolled patients from the New York AVM Databank were analyzed. AVM borderzone location was coded positive when the malformation was supplied by branches of at least 2 of the major circle of Willis arteries (anterior, middle, and/or posterior cerebral arteries). AVMs fed by branches of only 1 major pial or any other single artery served as a comparison group. Clinical presentation (diagnostic event) was categorized as (1) intracranial hemorrhage, proven by brain imaging, or (2) seizure, focal neurological deficit, headache, or other event with no signs of AVM hemorrhage on brain imaging. RESULTS: In 48% (n=222) of the patients, AVMs were located in the arterial borderzone territories; in 52% (n=242) a non-borderzone location was found. Hemorrhage was the presenting symptom in 44% (n=205); 28% (n=132) presented with seizures, 11% (n=52) with headaches, 7% (n=34) with a neurological deficit, and 9% (n=41) with other or no AVM-related symptoms. The frequency of incident AVM hemorrhage was significantly lower in borderzone AVMs (27%, n=61) than in non-borderzone malformations (60%, n=144; P:<0.001). This difference remained significant in a multivariate model controlling for age, sex, AVM size, deep venous drainage, and presence of aneurysms (odds ratio, 0.4; 95% CI, 0.25 to 0.66). CONCLUSIONS: Our findings suggest that borderzone location is an independent determinant for a lower risk of AVM hemorrhage at initial presentation.

Risk of endovascular treatment of brain arteriovenous malformations.

BACKGROUND AND PURPOSE: Independently assessed data on frequency, severity, and determinants of neurological deficits after endovascular treatment of brain arteriovenous malformations (AVMs) are scarce. METHODS: From the prospective Columbia AVM Study Project, 233 consecutive patients with brain AVM receiving > or =1 endovascular treatments were analyzed. Neurological impairment was assessed by a neurologist using the Rankin Scale before and after completed endovascular therapy. Multivariate logistic regression models were used to identify demographic, clinical, and morphological predictors of treatment-related neurological deficits. The analysis included the components used in the Spetzler-Martin risk score for AVM surgery (AVM size, venous drainage pattern, and eloquence of AVM location). RESULTS: The 233 patients were treated with 545 endovascular procedures. Mean follow-up time was 9.6 months (SD, 18.1 months). Two hundred patients (86%) experienced no change in neurological status after treatment, and 33 patients (14%) showed treatment-related neurological deficits. Of the latter, 5 (2%) had persistent disabling deficits (Rankin score >2), and 2 (1%) died. Increasing patient age [odds ratio (OR), 1.04; 95% confidence interval (CI), 1.01 to 1.08], number of embolizations (OR, 1.41; 95% CI, 1.16 to 1.70), and absence of a pretreatment neurological deficit (OR, 4.55; 95% CI, 1.03 to 20.0) were associated with new neurological deficits. None of the morphological AVM characteristics tested predicted treatment complications. CONCLUSIONS: From independent neurological assessment and prospective data collection, our findings suggest a low rate of disabling treatment complications in this center for endovascular brain AVM treatment. Risk predictors for endovascular treatment differ from those for AVM surgery.

Predictors of resource use after acute hospitalization: the Northern Manhattan Stroke Study.

OBJECTIVE: To determine demographic and clinical predictors of discharge destinations following acute care hospitalization for stroke in the community of northern Manhattan. METHODS: A group of 893 patients (mean age, 70 +/- 12 years; 56% women; 51% Hispanic, 30% African-American, 19% white) who survived acute care hospitalization for a first ischemic stroke were followed prospectively. Stroke severity was assessed by the NIH Stroke Scale and categorized as mild (< or = 5), moderate (6 to 13), and severe (> or = 14). Polytomous logistic regression was used to determine predictors for rehabilitation and nursing home placement versus returning home. RESULTS: Among the survivors of acute stroke care hospitalization, 611 (68%) patients were discharged to their homes, 168 (19%) to rehabilitation, and 114 (13%) to nursing homes. Patients with moderate and severe neurologic deficits had more than a threefold increased risk of being sent to a nursing home and more than an eightfold increased risk of being sent to rehabilitation. Age over 65 and cognitive impairment were associated with placement to a nursing home (age over 65: OR, 2.4; 95% CI, 1.0 to 5.6; cognitive impairment: OR, 2.9; 95%, CI 1.4 to 5.7), and rehabilitation (age over 65: OR, 1.8; 95% CI, 1.1 to 2.9; cognitive impairment: OR, 2.9; 95% CI, 1.4 to 5.7). CONCLUSION: Our results demonstrated that one-third of patients with acute stroke from the community of northern Manhattan required placement in a temporary or a long-term disability care institution following acute care hospitalization. Severity of stroke is an important factor that influences discharge planning following acute care hospitalization and its reduction can improve health care resource usage.

Dysarthria during basilar artery balloon occlusion.

A 49-year-old woman presenting with recurrent, reversible brainstem symptoms and a distal basilar artery aneurysm underwent balloon test occlusion. Five minutes after balloon inflation she developed a reversible isolated dysarthria. Despite failing the test occlusion (and after an additional brainstem event), the patient underwent surgery with placement of a clip across the basilar artery. The operation was tolerated without complication. The authors conclude that 1) pure dysarthria may be a symptom of temporary basilar artery occlusion and 2) balloon testing may overestimate the risk of basilar artery clipping.

Mortality and causes of death after first ischemic stroke: the Northern Manhattan Stroke Study.

OBJECTIVE: To analyze the early and long-term causes of death after first ischemic stroke in the multiethnic northern Manhattan community. METHODS: In the prospective, population-based Northern Manhattan Stroke Study, 980 patients with first ischemic stroke (mean age 70 years; 56% women; 49% Caribbean Hispanic, 31% black, 20% white) were followed for a mean of 3 years. Causes of death were classified as vascular (incident stroke, recurrent stroke, cardiac) or nonvascular. Life table analyses were used to assess mortality risks among different race-ethnic groups. Early (< or =1 month) vs long-term (> 1 month to 5 years) causes of death were compared. RESULTS: Among the 980 patients followed, 278 (28%) died; 47 (5%) died during the first month. Cumulative mortality risk was 5% at 1 month, 16% after 1 year, 29% after 3 years, and 41% after 5 years. The proportion of vascular deaths among all deaths was 75% at 1 month and 43% thereafter (p = 0.001). Stroke, either incident (53%) or recurrent (4%), caused early deaths in 57% and long-term deaths in 14% (p = 0.001). Overall mortality risks did not differ significantly among race-ethnic groups. However, the proportion of incident stroke-related early deaths was 85% in Caribbean Hispanic patients, 33% in white patients, and 25% in black patients (p = 0.002). CONCLUSIONS: Among patients with first ischemic stroke, incident stroke is the leading cause of early deaths. A large proportion of long-term deaths are nonvascular in origin. Despite similar overall mortality rates in race-ethnic groups, our data suggest a higher incident stroke-related early mortality among Caribbean Hispanics.

Outcome analysis of preoperative embolization with N-butyl cyanoacrylate in cerebral arteriovenous malformations.

PURPOSE: To determine the influence of preoperative N-butyl cyanoacrylate embolization on outcome in the treatment of cerebral arteriovenous malformations. METHODS: Two groups were compared: 30 patients who underwent surgery and embolization versus 41 patients who underwent surgery only. Both groups were categorized by Spetzler-Martin grade and evaluated with the Glasgow Outcome Scale at various intervals. The long-term follow-up in months was, for surgery only, mean of 35 and range of 4 to 59, and for surgery and embolization, mean of 10 and range of 1 to 19). RESULTS: The arteriovenous malformations in the surgery and embolization group had a larger average greatest diameter (4.2 +/- 1.5 cm versus 3.4 +/- 1.8 cm) and were of higher Spetzler-Martin grade (89% versus 68% grade III-V). No significant difference in the preoperative or immediate postoperative (less than 24 hours) Glasgow Outcome Scale was identified between the two groups. At I week after surgery, the surgery and embolization group displayed a significantly better outcome evaluation (70% versus 41% with Glasgow Outcome Scale score of 5). The long-term evaluation continued to favor the surgery and embolization patients (86% versus 66% with Glasgow Outcome Scale score of 5). CONCLUSION: Preoperative N-butyl cyanoacrylate embolization improves postsurgical outcome.

Determinants of resource utilization in the treatment of brain arteriovenous malformations.

BACKGROUND AND PURPOSE: Preoperative embolization of arteriovenous malformations (AVMs) is thought to improve outcome following surgical resection of these lesions. The purpose of this study was to examine the cost associated with preoperative embolization and different surgical risk categories in the surgical treatment of brain AVMs. METHODS: In a review of 126 patients treated surgically for resection of AVMs, we noted the total days spent in the hospital and calculated the associated costs (from hospital and estimated professional fees). Surgical risk category was determined using the Spetzler-Martin grading system. We examined the effect of risk category, preoperative embolization, and outcome (Rankin score) on cost and inpatient days. RESULTS: Preoperative embolization and greater surgical risk were independently associated with higher total costs. Average adjusted cost for embolization and surgery was $78,400 +/- $4,900 versus $49,300 +/- $5,800 for surgery alone. Patients ranged in preoperative risk category from Spetzler-Martin grades II through V, with an average increase of $20,100 in total cost per Spetzler-Martin grade (95% CI, $13,500 to $28,100). Higher surgical risk category was also associated with more days spent in hospital, with an average increase of 6 days per increment in Spetzler-Martin grade (95% CI, 4 to 8). After surgical resection of an AVM, new neurologic deficits were associated with large differences in cost: $68,500 +/- $6,100 and 15 +/- 2 days in hospital for patients who were neurologically worse after surgery, versus $44,700 +/- $3,900 and 10 +/- 1 days for patients who were unchanged. CONCLUSION: Preoperative embolization in the treatment of AVMs is associated with higher cost but not more days in the hospital. Patients with higher Spetzler-Martin grade AVMs utilize more hospital resources, in part because they have poorer neurologic outcome, and postoperative deficits are associated with higher costs and more days in the hospital.