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Object

Diffusion-weighted magnetic resonance (MR) imaging is an invaluable tool in the diagnosis of acute stroke and other types of brain injury. Abnormalities in and around the resection cavity on diffusion-weighted imaging have been observed following surgery for infiltrating glioma. The purpose of this study was to investigate prospectively the incidence, time course, and ultimate outcome of these abnormalities.

Methods

Forty-four consecutive patients with newly diagnosed gliomas were prospectively observed using serial MR imaging including diffusion-weighted sequences. Clinical and surgical data were also collected. Immediately postoperatively neuroimaging identified 28 patients (64%) in whom areas of reduced diffusion appeared in or around the resection cavity (mean volume 8.2 ± 1.5 cm³). Complete resolution of this reduced diffusion was demonstrated within 90 days in 24 patients (86%). On subsequent neuroimages these areas demonstrated Gd enhancement as early as postoperative Day 15 and as late as Day 198 and ultimately took on the appearance of encephalomalacia in 26 (93%) of 28 cases. Postoperative reduced diffusion was not predicted by the clinical or surgical parameters that were assessed. No clinical deficits were attributable to the reduced diffusion.

Conclusions

An abnormality related to diffusion-weighted sequences on postoperative MR imaging can occur after resection of newly diagnosed gliomas. In this study the abnormality typically resolved and was replaced by contrast enhancement on follow-up imaging, ultimately demonstrating encephalomalacia on long-term follow up. Findings on neuroimaging during the period of enhancement could be confused with recurrent tumor and interpreted as early treatment failure. Based on the findings of this study the authors strongly suggest that the inclusion of diffusion-weighted sequences in postoperative MR imaging is essential, as is MR imaging immediately before radiation therapy to monitor disease progression. A new enhancement observed after glioma surgery should be interpreted in the context of the diffusion-weighted image obtained immediately postoperatively.

Object

This study was designed to assess the presentation, management, and outcome of cases involving patients who had a supratentorial glioma that subsequently progressed in the posterior fossa (PF).

Methods

The authors performed a retrospective chart review of adult patients treated between 1997 and 2005 for supratentorial gliomas that progressed in the PF. The 29 patients with PF progression in this study were relatively young (median age of 34 years at original presentation). Twenty of these patients presented with symptoms. The symptoms were typically nonspecific to this population, at times leading to delays in diagnosis. Overall, these symptoms resolved in eight patients (40%) and progressed or remained unchanged in 12 (60%). Patients treated with more than 5000 cGy of radiation administered to the PF were more likely to have symptom resolution than those who received any other form of treatment, including reduced doses of radiation (p = 0.004). The patients treated with higher doses also survived significantly longer after PF progression (univariate analysis, p = 0.01, and after adjusting for tumor grade, p = 0.04).

Conclusions

Patients with PF progression of supratentorial infiltrative gliomas may benefit from treatment, and the authors recommend more than 5000 cGy of radiation to the PF if prior radiotherapy ports and doses allow.

Object

The clinical behavior of meningiomas is variable. Because multiple growth factor receptors have been identified in these tumors, the authors sought to assess the capacity of the expression patterns of a subset of these receptors to stratify meningioma cases.

Methods

Eighty-four meningiomas were analyzed, including 36 benign, 29 atypical, and 19 malignant lesions. Immunohistochemical staining was performed for epidermal growth factor receptor (EGFR), platelet-derived growth factor receptor (PDGFR)–β, basic fibroblast growth factor receptor (BFGFR), and MIB-1. Survival analyses were performed using follow-up data obtained in patients with newly diagnosed tumors.

Immunoreactivity for EGFR was observed in 47% of benign, 48% of atypical, and 42% of malignant tumors. Staining for BFGFR was identified in 89% of benign, 97% of atypical, and 95% of malignant lesions. Immunostaining for PDGFR-β was evident in all the lesions assessed. Mean MIB-1 indices for benign, atypical, and malignant cases were 3.6 (range 0.5–15.3), 8.2 (range 1.5–23.1) and 18.3 (range 1.0–55.8), respectively. Overall mean follow-up duration was 9.0 years (range 5.1–18.8 years). Lack of EGFR immunoreactivity was identified as a strong predictor of shorter overall survival in patients with atypical meningioma (p = 0.003, log-rank test). This association was not evident in cases of benign or malignant meningiomas.

Conclusions

There is a significant association between EGFR immunoreactivity and prolonged survival in patients with atypical meningioma. Given the variable behavior of atypical meningiomas, EGFR assessment could improve existing strategies for patient stratification and treatment.

Object

Adults with scoliosis often present with neurological symptoms and deficits. However, the incidence of these findings and how they may affect treatment decisions have not been clearly defined. The purpose of this study was to quantify the prevalence of neurological symptoms and deficits in adults with scoliosis presenting to a surgical clinic, and to assess for an association between these factors and the decision to pursue operative treatment.

Methods

In this study, the authors document the Oswestry Disability Index (ODI), radiographic findings, and the incidences of back pain, neurological symptoms (radiculopathy and claudication), and neurological deficits (weakness, myelopathy, and bowel/bladder dysfunction) and correlate these with operative versus nonoperative management. Pain was assessed using the visual analog scale (VAS) score. Of 207 patients, 25% underwent surgery.

Results

Incidences of back pain (VAS score > 0 points) and radiculopathy (VAS score > 0) were 99 and 85%, respectively. The incidences of severe (VAS score > 5) back pain and radiculopathy were 66 and 47%, respectively. Neurological symptoms and deficits included weakness in 8% of patients, claudication in 9%, myelopathy in 1%, and bowel/bladder dysfunction in 3%. Patients with severe radiculopathy had greater mean ODI scores (p < 0.001) and reduced lumbar lordosis (p = 0.04) and were more likely to have de novo scoliosis (p = 0.009). Patients who underwent surgery had higher ODI scores (p < 0.001) and a greater incidence of severe radiculopathy (p = 0.006), weakness (p < 0.001), and neurogenic claudication (p = 0.003). Factors associated with operative management on multivariate analysis included weakness (p < 0.001), severe radiculopathy (p = 0.02), and sagittal imbalance (p = 0.03).

Conclusions

Neurological symptoms and deficits are common among adults with scoliosis. Development of neurological symptoms and/or deficits is strongly associated with the decision to pursue operative treatment.

Object

Hemispheric low-grade gliomas (LGGs) have an unpredictable progression and overall survival (OS) profile. As a result, the objective in the present study was to design a preoperative scoring system to prognosticate long-term outcomes in patients with LGGs.

Methods

The authors conducted a retrospective review with long-term follow-up of 281 adults harboring hemispheric LGGs (World Health Organization Grade II lesions). Clinical and radiographic data were collected and analyzed to identify preoperative predictors of OS, progression-free survival (PFS), and extent of resection (EOR). These variables were used to devise a prognostic scoring system.

Results

The 5-year estimated survival probability was 0.86. Multivariate Cox proportional hazards modeling demonstrated that 4 factors were associated with lower OS: presumed eloquent location (hazard ratio [HR] 4.12, 95% confidence interval [CI] 1.71–10.42), Karnofsky Performance Scale score ≤ 80 (HR 3.53, 95% CI 1.56–8.00), patient age > 50 years (HR 1.96, 95% CI 1.47–3.77), and tumor diameter > 4 cm (HR 3.43, 95% CI 1.43–8.06). A scoring system calculated from the sum of these factors (range 0–4) demonstrated risk stratification across study groups, with the following 5-year cumulative survival estimates: Scores 0–1, OS = 0.97, PFS = 0.76; Score 2, OS = 0.81, PFS = 0.49; and Scores 3–4, OS = 0.56, PFS = 0.18 (p < 0.001 for both OS and PFS, log-rank test). This proposed scoring system demonstrated a high degree of interscorer reliability (kappa = 0.86). Four illustrative cases are described.

Conclusions

The authors propose a simple and reliable scoring system that can be used to preoperatively prognosticate the degree of lesion resectability, PFS, and OS in patients with LGGs. The application of a standardized scoring system for LGGs should improve clinical decision-making and allow physicians to reliably predict patient outcome at the time of the original imaging-based diagnosis.

Object

Medical and surgical management of low-grade gliomas (LGGs) is complicated by a highly variable clinical course. The authors recently developed a preoperative scoring system to prognosticate outcomes of progression and survival in a cohort of patients treated at a single institution (University of California, San Francisco [UCSF]). The objective of this study was to validate the scoring system in a large patient group drawn from multiple external institutions.

Methods

Clinical data from 3 outside institutions (University of Utah, Toronto Western Hospital, and University of California, Los Angeles) were collected for 256 patients (external validation set). Patients were assigned a prognostic score based upon the sum of points assigned to the presence of each of the 4 following factors: 1) location of tumor in presumed eloquent cortex, 2) Karnofsky Performance Scale (KPS) Score ≤ 80, 3) age > 50 years, and 4) maximum diameter > 4 cm. A chi-square analysis was used to analyze categorical differences between the institutions; Cox proportional hazard modeling was used to confirm that the individual factors were associated with shorter overall survival (OS) and progression-free survival (PFS); and Kaplan–Meier curves estimated OS and PFS for the score groups. Differences between score groups were analyzed by the log-rank test.

Results

The median OS duration was 120 months, and there was no significant difference in survival between the institutions. Cox proportional hazard modeling confirmed that the 4 components of the UCSF Low-Grade Glioma Scoring System were associated with lower OS in the external validation set; presumed eloquent location (hazard ratio [HR] 2.04, 95% CI 1.28–2.56), KPS score ≤ 80 (HR 5.88, 95% CI 2.44–13.7), age > 50 years (HR 1.82, 95% CI 1.02–3.23), and maximum tumor diameter > 4 cm (HR 2.63, 95% CI 1.58–4.35). The stratification of patients based on scores generated groups (0–4) with statistically different OS and PFS estimates (p < 0.0001, log-rank test). Lastly, the UCSF patient group (construction set) was combined with the external validation set (total of 537 patients) and analyzed for OS and PFS. For all patients, the 5-year survival probability was 0.79; the 5-year cumulative OS probabilities stratified by score group were: score of 0, 0.98; score of 1, 0.90; score of 2, 0.81; score of 3, 0.53; and score of 4, 0.46.

Conclusions

The UCSF scoring system accurately predicted OS and PFS in an external large, multiinstitutional population of patients with LGGs. The strengths of this system include ease of use and ability to be applied preoperatively, with the eventual goal of aiding in the design of individualized treatment plans for patients with LGG at diagnosis.

Object

The purpose of this study was to evaluate the prospectively collected Scoliosis Research Society (SRS) database to assess the incidences of morbidity and mortality (M&M) in the operative treatment of degenerative lumbar stenosis, one of the most common procedures performed by spine surgeons.

Methods

All patients who underwent surgical treatment for degenerative lumbar stenosis between 2004 and 2007 were identified from the SRS M&M database. Inclusion criteria for analysis included an age ≥ 21 years and no history of lumbar surgery. Patients were treated with either decompression alone or decompression with concomitant fusion. Statistical comparisons were performed using a 2-sided Fisher exact test.

Results

Of the 10,329 patients who met the inclusion criteria, 6609 (64%) were treated with decompression alone, and 3720 (36%) were treated with decompression and fusion. Among those who underwent fusion, instrumentation was placed in 3377 (91%). The overall mean patient age was 63 ± 13 years (range 21–96 years). Seven hundred nineteen complications (7.0%), including 13 deaths (0.1%), were identified. New neurological deficits were reported in 0.6% of patients. Deaths were related to cardiac (4 cases), respiratory (5 cases), pulmonary embolus (2 cases), and sepsis (1 case) etiologies, and a perforated gastric ulcer (1 case). Complication rates did not differ based on patient age or whether fusion was performed. Minimally invasive procedures were associated with fewer complications and fewer new neurological deficits (p = 0.01 and 0.03, respectively).

Conclusions

The results from this analysis of the SRS M&M database provide surgeons with useful information for preoperative counseling of patients contemplating surgical intervention for symptomatic degenerative lumbar stenosis.