Spinal meningiomas, from biology to management - A literature review.

Meningiomas arise from arachnoidal cap cells of the meninges, constituting the most common type of central nervous system tumors, and are considered benign tumors in most cases. Their incidence increases with age, and they mainly affect females, constituting 25-46% of primary spinal tumors. Spinal meningiomas could be detected incidentally or be unraveled by various neurological symptoms (e.g., back pain, sphincter dysfunction, sensorimotor deficits). The gold standard diagnostic modality for spinal meningiomas is Magnetic resonance imaging (MRI) which permits their classification into four categories based on their radiological appearance. According to the World Health Organization (WHO) classification, the majority of spinal meningiomas are grade 1. Nevertheless, they can be of higher grade (grades 2 and 3) with atypical or malignant histology and a more aggressive course. To date, surgery is the best treatment where the big majority of meningiomas can be cured. Advances in surgical techniques (ultrasonic dissection, microsurgery, intraoperative monitoring) increase the complete resection rate. Operated patients have a satisfactory prognosis, even in those with poor preoperative neurological status. Adjuvant therapy has a growing role in treating spinal meningiomas, mainly in the case of subtotal resection and tumor recurrence. The current paper reviews the fundamental epidemiological and clinical aspects of spinal meningiomas, their histological and genetic characteristics, and their management, including the various surgical novelties and techniques.

Impact of New Systemic Treatment and Radiotherapy in Melanoma Patients with Leptomeningeal Metastases.

IMPORTANCE: Few data are available on patients with leptomeningeal disease (LM) from melanoma treated with new systemic therapies. OBJECTIVE: To gain a better understanding of patients, disease characteristics, and therapeutic interventions in melanoma patients with LM in the era of new systemic treatment. DESIGN: Clinical characteristics, treatments, and survival of melanoma patients diagnosed with LM, isolated or associated with brain metastases, were collected. The Cox regression model assessed the influence of patient and melanoma characteristics on survival. SETTING: Monocentric, retrospective, real-life cohort of patients with LM from melanoma. PARTICIPANTS: All patients followed up at Saint-Louis University Hospital and diagnosed with LM between December 2013 and February 2020 were included. For each patient identified, a central review by dermato-oncologist and neuro-oncologist experts was performed to confirm the diagnosis of LM. EXPOSURE: Impact of new systemic therapies and radiotherapy. RESULTS: Among the 452 advanced melanoma patients followed at St Louis Hospital between 2013 and 2020, 41 patients with LM from melanoma were identified. Among them, 29 patients with a diagnosis of LM "confirmed" or "probable" after central neuro-oncologists reviewing were included. Nineteen patients had known melanoma brain metastases at LM diagnosis. Among the 27 patients treated with systemic therapy, 17 patients were treated with immunotherapy, 5 patients received targeted therapy, 1 was treated with chemotherapy, and 4 patients were treated with anti-PD-1 in combination with BRAF inhibitor. The median overall survival (OS) from LM diagnosis was 5.1 months. Median OS was 7.1 months for the 9 patients receiving systemic therapy combined with radiotherapy, and 3.2 months for the 20 patients not receiving combined radiotherapy. Elevated serum lactate dehydrogenase (LDH) (HR 1.44, 95% CI 1.09-1.90, p < 0.01) and presence of neurological symptoms at LM diagnosis (HR 2.96, 95% CI 1.25-6.99, p = 0.01) were associated with poor survival. At the time of data analysis, five patients were still alive with a median follow-up of 47.4 months and had persistent complete response. CONCLUSION: Targeted therapy and immunotherapy are promising new treatment options in LM from melanoma that can increase overall survival, and may induce long lasting remission in some patients.

Small vessel disease in patients with subarachnoid hemorrhage: Prevalence and associations with vasospasm occurrence, severity and clinical outcomes.

PURPOSE: Investigating the associations between cerebral small vessel disease (cSVD) burden and cerebral vasospasm (CVS), delayed cerebral ischemia (DCI) and clinical outcomes in patients with aneurysmal subarachnoid hemorrhage (aSAH). METHODS: Consecutive aSAH patients with initial (<7 days after onset) and 3-month follow-up brain magnetic resonance imaging (MRI) and clinical evaluation at 6 months were included. The cSVD burden score was built using MRI criteria. CVS was defined according to transcranial Doppler examination and computed tomography (CT) or digital subtraction angiography. DCI was defined by the appearance of hyperintense fluid-attenuated inversion recovery lesions, with territorial or cortico-subcortical distribution, between initial MRI and 3-month MRI. The modified Rankin scale of ≤2 at 6 months was considered a favorable outcome. Using univariate and multivariable analyses, we investigated the associations between cSVD and CVS, DCI and clinical outcome. RESULTS: A total of 113 patients were included in the study sample (median age 49.1 years (IQR 42.1-60.8), 70/113 females). The burden of cSVD was mild with a median of 0 (IQR 0-1). When comparing patients with no/mild versus those with moderate/severe cSVD burden, we did not find a univariable difference regarding vasospasm occurrence (60% versus 46.1%, p = 0.54), DCI (20.2% versus 23%, p = 0.66) or favorable outcome at 3 months (94% versus 83.3%, p = 0.20). There was a univariable trend towards more frequent favorable outcome in patients with no/milde white matter hyperintensities versus those with moderate/severe white matter hyperintensities (92% versus 85%, p = 0.09). In multivariable models, cSVD markers were not associated with CVS occurrence and severity, DCI or clinical outcome. CONCLUSIONS: In patients with mild aSAH, the burden of cSVD as assessed by MRI is minimal and is not associated with CVS, DCI or clinical outcome.

Real-time Brain Tumor imaging with endogenous fluorophores: a diagnosis proof-of-concept study on fresh human samples.

The primary line of therapy for high-grade brain tumor is surgical resection, however, identifying tumor margins in vivo remains a major challenge. Despite the progress in computer-assisted imaging techniques, biopsy analysis remains the standard diagnostic tool when it comes to delineating tumor margins. Our group aims to answer this challenge by exploiting optical imaging of endogenous fluorescence in order to provide a reliable and reproducible diagnosis close to neuropathology. In this study, we first establish the ability of two-photon microscopy (TPM) to discriminate normal brain tissue from glioblastomas and brain metastasis using the endogenous fluorescence response of fresh human brain sample. Two-photon fluorescence images were compared to gold standard neuropathology. "Blind" diagnosis realized by a neuropathologist on a group of TPM images show a good sensitivity, 100%, and specificity, 50% to discriminate non tumoral brain tissue versus glioblastoma or brain metastasis. Quantitative analysis on spectral and fluorescence lifetime measurements resulted in building a scoring system to discriminate brain tissue samples.

Circumferential Thick Enhancement at Vessel Wall MRI Has High Specificity for Intracranial Aneurysm Instability.

Purpose To identify wall enhancement patterns on vessel wall MRI that discriminate between stable and unstable unruptured intracranial aneurysm (UIA). Materials and Methods Patients were included from November 2012 through January 2016. Vessel wall MR images were acquired at 3 T in patients with stable (incidental and nonchanging over 6 months) or unstable (symptomatic or changing over 6 months) UIA. Each aneurysm was evaluated by using a four-grade classification of enhancement: 0, none; 1, focal; 2, thin circumferential; and 3, thick (>1 mm) circumferential. Inter- and intrareader agreement for the presence and the grade of enhancement were assessed by using κ statistics and 95% confidence interval (CI). The sensitivity, specificity, and negative and positive predictive values of each enhancement grade for differentiating stable from unstable aneurysms was compared. Results The study included 263 patients with 333 aneurysms. Inter- and intrareader agreement was excellent for both the presence of enhancement (κ values, 0.82 [95% CI: 0.67, 0.99] and 0.87 [95% CI: 0.7, 1.0], respectively) and enhancement grade (κ = 0.92 [95% CI: 0.87, 0.95]). In unruptured aneurysms (n = 307), grade 3 enhancement exhibited the highest specificity (84.4%; 233 of 276; 95% CI: 80.1%, 88.7%; P = .02) and negative predictive value (94.3%; 233 of 247) for differentiating between stable and unstable lesions. There was a significant association between grade 3 enhancement and aneurysm instability (P < .0001). Conclusion In patients with intracranial aneurysm, a thick (>1 mm) circumferential pattern of wall enhancement demonstrated the highest specificity for differentiating between stable and unstable aneurysms. © RSNA, 2018.

Screening for intracranial aneurysms in autosomal dominant polycystic kidney disease is cost-effective.

Intracranial aneurysm rupture is a dramatic complication of autosomal dominant polycystic kidney disease (ADPKD). It remains uncertain whether screening should be widespread or only target patients with risk factors (personal or familial history of intracranial aneurysm), with an at-risk profession, or those who request screening. We evaluated this in a single-center cohort of 495 consecutive patients with ADPKD submitted to targeted intracranial aneurysm screening. Cerebral magnetic resonance angiography was proposed to 110 patients with a familial history of intracranial aneurysm (group 1), whereas it was not our intention to propose it to 385 patients without familial risk (group 2). Magnetic resonance angiography results, intracranial aneurysm prophylactic repair, rupture events, and cost-effectiveness of intracranial aneurysm screening strategies were retrospectively analyzed. During a median follow up of 5.9 years, five non-fatal intracranial aneurysm ruptures occurred (incidence rate 2.0 (0.87-4.6)/1000 patients-year). In group 1, 90% of patients were screened and an intracranial aneurysm was detected in 14, treated preventively in five, and ruptured in one patient despite surveillance. In group 2, 21% of patients were screened and an intracranial aneurysm was detected in five, and treated preventively in one. Intracranial aneurysm rupture occurred in four patients in group 2. Systematic screening was deemed cost-effective and provides a gain of 0.68 quality-adjusted life years compared to targeted screening. Thus, the intracranial aneurysm rupture rate is high in ADPKD despite targeted screening, and involves mostly patients without familial risk factors. Hence, cost-utility analysis suggests that intracranial aneurysm screening could be proposed to all ADPKD patients.

[Screening and management of intracranial aneurisms in patients with autosomal dominant polycystic kidney disease]. / Dépistage et prise en charge des anévrismes intracrâniens chez les patients atteints de polykystose rénale autosomique dominante.

Autosomal dominant polycystic kidney disease is the most frequent hereditary kidney disease. Intracranial aneurysm prevalence in this population is four to five times higher than the prevalence in the general population. The most frequent complication of intracranial aneurysms is rupture with subarachnoidal hemorrhage, which is associated with a high morbidity and mortality. The only identified risk factor for unruptured intracranial aneurysm is a family history of intracranial aneurysm. However, most cases of aneurysm rupture occur without any family history of intracranial aneurysm. Magnetic resonance angiography without contrast medium injection facilitates screening, and progress have been made in preventive (endovascular or neurosurgical) treatment of intracranial aneurysm. Recommendations have recently been published concerning intracranial aneurysm screening, and suggest screening patients with autosomal dominant polycystic kidney disease and a family history of intracranial aneurysm, those who have an at-risk activity and those who request screening despite adequate information. Conflicting opinions exist, however, in the literature. Furthermore, a study of practice was conducted among French-speaking nephrologists in Europe and showed that approximately a third of the participants were in favor of systematic screening for intracranial aneurysm in all patients with autosomal dominant polycystic kidney disease. Beyond intracranial aneurysm prevalence, it is necessary to better define rupture rates in the autosomal dominant polycystic kidney disease population, with and without familial history of intracranial aneurysm. This would allow optimizing intracranial aneurysm screening practices in autosomal dominant polycystic kidney disease.

Multimodal optical analysis discriminates freshly extracted human sample of gliomas, metastases and meningiomas from their appropriate controls.

Delineating tumor margins as accurately as possible is of primordial importance in surgical oncology: extent of resection is associated with survival but respect of healthy surrounding tissue is necessary for preserved quality of life. The real-time analysis of the endogeneous fluorescence signal of brain tissues is a promising tool for defining margins of brain tumors. The present study aims to demonstrate the feasibility of multimodal optical analysis to discriminate fresh samples of gliomas, metastases and meningiomas from their appropriate controls. Tumor samples were studied on an optical fibered endoscope using spectral and fluorescence lifetime analysis and then on a multimodal set-up for acquiring spectral, one and two-photon fluorescence images, second harmonic generation signals and two-photon fluorescence lifetime datasets. The obtained data allowed us to differentiate healthy samples from tumor samples. These results confirmed the possible clinical relevance of this real-time multimodal optical analysis. This technique can be easily applied to neurosurgical procedures for a better delineation of surgical margins.

Multimodal optical analysis of meningioma and comparison with histopathology.

Meningioma is the most frequent primary central nervous system tumor. The risk of recurrence and the prognosis are correlated with the extent of the resection that ideally encompasses the infiltrated dura mater and, if required, the infiltrated bone. No device can deliver real-time intraoperative histopathological information on the tumor environment to help the neurosurgeon to achieve a gross total removal. This study assessed the abilities of nonlinear microscopy to provide relevant and real-time data to help resection of meningiomas. Nine human meningioma samples (four World Health Organization Grade I, five Grade II) were analyzed using different optical modalities: spectral analysis and imaging, lifetime measurements, fluorescence lifetime imaging microscopy, fluorescence emitted under one- and two-photon excitation and the second-harmonic generation signal imaging using a multimodal setup. Nonlinear microscopy produced images close to histopathology as a gold standard. The second-harmonic generation signal delineated the collagen background and two-photon fluorescence underlined cell cytoplasm. The matching between fluorescence images and Hematoxylin and Eosin staining was possible in all cases. Grade I meningioma emitted less autofluorescence than Grade II meningioma and Grade II meningioma exhibited a distinct lifetime value. Autofluorescence was correlated with the proliferation rates and seemed to explain the observed differences between Grade I and II meningiomas. This preliminary multimodal study focused on human meningioma samples confirms the potential of tissue autofluorescence analysis and nonlinear microscopy in helping intraoperatively neurosurgeons to reach the actual boundaries of the tumor infiltration. Correspondence between H&E staining (top pictures) and the two-photon fluorescence imaging (bottom pictures).

Screening for Unruptured Intracranial Aneurysms in Autosomal Dominant Polycystic Kidney Disease: A Survey of 420 Nephrologists.

BACKGROUND: Despite a high prevalence of intracranial aneurysm (ICA) in autosomal dominant polycystic kidney disease (ADPKD), rupture events are rare. The current recommendations for ICA screening are based on expert opinions and studies with low levels of evidence. OBJECTIVES: The aim of our study was to describe the attitudes of practicing nephrologists in Europe towards screening for ICA using magnetic resonance angiography (MRA). METHODS: We conducted a web-based survey among 1315 European French-speaking nephrologists and nephrology residents. An anonymous, electronic questionnaire including 24 independent questions related to ICA screening modalities, indications and participant profiles was sent by email between September and December 2014. Four hundred and twenty nephrologists (mostly from France) participated, including 31 nephrology residents; the response rate was 32%. RESULTS: Systematic screening for ICA was advocated by 28% of the nephrologists. A family history of ICA rupture, sudden death, stroke and migraine were consensual indications for screening (> 90% of the panel). In other clinical situations largely not covered by the recommendations (pregnancy, nephrectomy, kidney transplantation, cardiac or hepatic surgery, uncontrolled hypertension, lack of familial ADPKD history, at-risk activity, tobacco use), the attitudes towards screening were highly divergent. ICA screening was influenced by nephrologists experience with ADPKD and by their practice setting. The majority of participants (57%) would not repeat a normal ICA screening. Only a few participants (22%) knew that non-contrast MRA was the reference diagnostic tool for ICA screening, whereas most participants thought that contrast enhancement was necessary to screen for ICA. The results from the nephrology residents were analyzed separately and yielded similar results. CONCLUSION: This practice survey revealed that most nephrologists follow the current recommendations for the initial screening of ICAs. However, more than a quarter of the panel was in favor of systematic ICA screening, most nephrologists did not know that contrast medium was not necessary to screen for ICA using MRA, and many areas of uncertainty remain.

Combining intraoperative carmustine wafers and Stupp regimen in multimodal first-line treatment of primary glioblastomas.

BACKGROUND: The study investigated if intraoperative use of carmustine wafers, particularly in combination with Stupp regimen, is a viable and safe first-line treatment option of glioblastomas. METHODS: Eighty-three consecutive adult patients (50 men; mean age 60 years) with newly diagnosed supratentorial primary glioblastomas that underwent surgical resection with intraoperative carmustine wafers implantation (n = 7.1 ± 1.7) were retrospectively studied. RESULTS: The median overall survival (OS) was 15.8 months with 56 patients dying over the course of the study. There was no significant association between the number of implanted carmustine wafers and complication rates (four surgical site infections, one death). The OS was significantly longer in Stupp regimen patients (19.5 months) as compared with patients with other postoperative treatments (13 months; p = 0.002). In addition patients with eight or more implanted carmustine wafers survived longer (24.5 months) than patients with seven or less implanted wafers (13 months; p = 0.021). Finally, regardless of the number of carmustine wafers, median OS was significantly longer in patients with a subtotal or total resection (21.5 months) than in patients with a partial resection (13 months; p = 0.011). CONCLUSIONS: The intraoperative use of carmustine wafers in combination with Stupp regimen is a viable first-line treatment option of glioblastomas. The prognostic value of this treatment association should be evaluated in a multicenter trial, ideally in a randomized and placebo-controlled one.

Does aneurysmal wall enhancement on vessel wall MRI help to distinguish stable from unstable intracranial aneurysms?

BACKGROUND AND PURPOSE: Arterial wall enhancement on vessel wall MRI was described in intracranial inflammatory arterial disease. We hypothesized that circumferential aneurysmal wall enhancement (CAWE) could be an indirect marker of aneurysmal wall inflammation and, therefore, would be more frequent in unstable (ruptured, symptomatic, or undergoing morphological modification) than in stable (incidental and nonevolving) intracranial aneurysms. METHODS: We prospectively performed vessel wall MRI in patients with stable or unstable intracranial aneurysms. Two readers independently had to determine whether a CAWE was present. RESULTS: We included 87 patients harboring 108 aneurysms. Interreader and intrareader agreement for CAWE was excellent (κ=0.85; 95% confidence interval, 0.75-0.95 and κ=0.90; 95% confidence interval, 0.83-0.98, respectively). A CAWE was significantly more frequently seen in unstable than in stable aneurysms (27/31, 87% versus 22/77, 28.5%, respectively; P<0.0001). Multivariate logistic regression, including CAWE, size, location, multiplicity of aneurysms, and daily aspirin intake, revealed that CAWE was the only independent factor associated with unstable status (odds ratio, 9.20; 95% confidence interval, 2.92-29.0; P=0.0002). CONCLUSIONS: CAWE was more frequently observed in unstable intracranial aneurysms and may be used as a surrogate of inflammatory activity in the aneurysmal wall.

[Subarachnoid hemorrhage in young patients]. / Hémorragie méningée du sujet jeune.

Subarachnoid hemorrhage (SAH) accounts for 5 % of strokes with a high rate of death and morbidity. It occurs in young patients, often hypertensive and smoking. Patients usually present with sudden headache. Initial clinical evaluation uses a prognosis grading scale including level of consciousness and motor deficit on admission (WFNS scale). Unenhanced CT brain imaging demonstrates the SHA together with evaluation of the initial blood amount, predictive of the occurrence of cerebral vasospasm that may lead to delayed cerebral ischemia. After referral to a multidisciplinary center with neurovascular expertise, MR, CT and/or catheter angiography detects the ruptured aneurysm, the cause of SAH in 85 % of cases. Since rebleeding is an imminent danger, occlusion of the aneurysm should be performed, as soon as possible and within the first 72 heures, either by an endovascular or microsurgical approach. Medical management includes early detection of hydrocephalus and cerebral vasospasm is a devastating complication inducing death and functional impairment. Prevention strategies remain limited and include maintenance of normovolemia and calcium antagonists such as nimodipine. Treatment of cerebral vasospasm associates maintenance of cerebral perfusion and more invasive techniques such as chemical or mechanical angioplasty.

The protective status of subtotal obliteration of arteriovenous malformations after radiosurgery: significance and risk of hemorrhage.

OBJECTIVE: Arteriovenous malformations (AVMs) treated by radiosurgery with complete obliteration of the nidus but a persisting early draining vein on follow-up angiography can be termed subtotally obliterated. However, these are persistent circulating AVMs. The significance of these lesions, their hemorrhage rate, and their management are analyzed. METHODS: In a series of 862 consecutive patients with AVMs treated by radiosurgery, 121 patients (14%) achieved subtotal obliteration (STO). The angiographic evolution and rate of obliteration were studied. The pretreatment angiographic features, dosimetric parameters, and postradiosurgery hemorrhage rate were compared with those in the rest of the treated population. Finally, the options for follow-up and treatment were analyzed. RESULTS: Of 121 subtotally obliterated AVMs, the bleeding rate was 0%; 53% of patients achieved complete obliteration. This occurred in 71% of those who had STO at 1 year. In the cases in which STO was detected at 2, 3, and 4 years, total obliteration eventually occurred in 43%, 28.5%, and 0%, respectively. Comparative analysis with AVMs in which a part of the nidus persisted showed a significant difference in the bleeding rate. Except for volume, no significant statistical difference in angiographic and dosimetric parameters was found between the STO group and the rest of the studied population with residual nidus. Six cases received further treatment, resulting in 2 cures and 2 treatment-related complications. CONCLUSION: Subtotally obliterated AVMs are different from other partially obliterated AVMs, with a 0% bleeding rate. Their complete obliteration is a function of delay of appearance on follow-up angiography. Invasive follow-up and further treatment of these AVMs do not seem warranted.

Three-dimensional dynamic time-resolved contrast-enhanced MRA using parallel imaging and a variable rate k-space sampling strategy in intracranial arteriovenous malformations.

PURPOSE: To evaluate the effectiveness of three-dimensional (3D) dynamic time-resolved contrast-enhanced MRA (TR-CE-MRA) using a combination of a parallel imaging technique (ASSET: array spatial sensitivity encoding technique) and a time-resolved method (TRICKS: time-resolved imaging of contrast kinetics) and to compare it with 3D dynamic TR-CE-MRA using ASSET alone in the assessment of intracranial arteriovenous malformations (AVMs). MATERIALS AND METHODS: Twenty consecutive patients with angiographically confirmed AVMs were investigated using both 3D dynamic TR-CE-MRA techniques. Examinations were compared with respect to image quality, spatial resolution, number and type of feeders and drainers, nidus size, presence of early venous filling and temporal resolution. Digital subtraction angiography was used as standard of reference. RESULTS: The higher temporal and spatial resolution of 3D dynamic TR-CE-MRA TRICKS ASSET allowed a better assessment of intracranial vascular malformations, namely better depiction of feeders, drainers and better detection of early venous drainage. There was no significant difference between them in terms of nidus size. CONCLUSION: 3D dynamic TR-CE-MRA combining parallel imaging and a time-resolved method with subsecond and submillimeter resolution could become the first-line investigation technique in both diagnosis and follow-up of intracranial AVMs.

Radiosurgery with or without A 2-mm margin for 93 single brain metastases.

PURPOSE: Retrospective comparison of Linac radiosurgery (RS) in 93 single brain metastases with or without a 2-mm margin. PATIENTS AND METHODS: A total of 153 patients had Linac RS (between April 1992 and June 2004), with 139 patients (90.8%) evaluable in June 2005. Sixty-one patients (44%) had extracranial lesions and 65 patients had neurologic symptoms (47%). RS alone: 105 patients (66%); RS +whole brain radiotherapy: 34 patients (24%). Single metastasis: 93/139 patients; classic RS: 42/93 patients; 2-mm margin: 51/93 patients; 30 multiple lesions patients were excluded. TREATMENT: 15 Mv X-ray Linac, circular minibeams, 8-30 mm, four to six noncoplanar coronal arcs. Isodose was 60-80%; doses were 10-20 Gy. FOLLOW-UP: 12 months-13 years; median, 14 months. RESULTS: Local control (LC) was not improved in 51 margin patients vs. 42 classic RS patients: 1 year: 69.1% and 72.4%. Two-year LC rate: 64% and 54.7%, respectively. Survival: median classic RS: 11.3 months; margin RS, 19 months (p = 0.34) and 1 year, 41.6% and 60.2%, respectively. Margin RS patients had a significantly higher rate of severe parenchymal complications: 19.6% vs. 7.1% (p = 0.02); surgery was necessary in 4 of 51 cases vs. 1 of 42 classic RS cases. CONCLUSION: No increase of 1- and 2-year LC rate in margin RS or survival and median survival: 11.3 vs. 19 months (NS) 2-mm margin associated with more severe parenchymal complications (p = 0.02). This procedure is therefore not recommended. Late CT images and 1-mm margin as recommended by pathologists, use of three-dimensional magnetic resonance imaging and fuzzy method to calculate volumes may yield better results. Stereotactic hypofractionation requires further studies.

Microsurgery or radiosurgery for cerebral arteriovenous malformations? A study of two paired series.

OBJECTIVE: To detect parameters that may augment the therapeutic strategy in patients with a cerebral arteriovenous malformation (AVM) that is considered equally suitable for treatment by neurosurgery or radiosurgery, we compared the efficacy and risks of these two methods in a paired series with similar patient and AVM characteristics. PATIENTS AND METHODS: Two series of patients with AVM were studied, including a series of 39 patients treated using microsurgery (MS) and another series of 39 patients treated via radiosurgery (RS). These series were paired for age and sex, initial symptoms, size, location and Spetzler-Martin grade, and presence of embolization preceding treatment. We compared the posttreatment outcome in the two groups with respect to obliteration rate, neurological status, mortality rate, and recurrent bleeding. Statistical analysis was performed using paired Student's t test. RESULTS: The Glasgow Outcome Scale values and Modified Rankin Scores measured at discharge and 12 to 24 months were significantly better in the RS series than in the MS series. The obliteration rate tended to be higher in the MS series (91% versus 81%; P = 0.10, not significant), whereas the rate of neurological deficit was higher in the MS series than in the RS series (P < 0.001). The mortality rate was not significantly different in the two series, but the rate of recurrent bleeding was higher in the RS group (10% versus 0%; P = 0.04). CONCLUSIONS: Although the rate of cure was similar for patients treated with MS and RS, neurological morbidity was higher after MS and recurrent bleeding was more frequent after RS.

Three-dimensional dynamic magnetic resonance angiography for the evaluation of radiosurgically treated cerebral arteriovenous malformations.

We assessed the value of three-dimensional (3D) dynamic magnetic resonance angiography (MRA) for the follow-up of patients with radiosurgically treated cerebral arteriovenous malformations (AVMs). Fifty-four patients with cerebral AVMs treated by radiosurgery (RS) were monitored using conventional catheter angiography (CCA) and 3D dynamic MRA with sensitivity encoding based on the parallel imaging. Cerebral AVM was qualitatively classified by two radiologists into one of five categories in terms of residual nidus size and persistence of early draining vein (I, >6 cm; II, 3-6 cm; III, <3 cm; IV, isolated early draining vein; V, complete obliteration). 3D MRA findings showed a good agreement with CCA in 40 cases (kappa=0.62). Of 23 nidus detected on CCA, 3D dynamic MRA showed 14 residual nidus. Of 28 occluded nidus on 3D dynamic MRA, 22 nidus were occluded on CCA. The sensitivity and specificity of 3D dynamic MRA for the detection of residual AVM were 81% and 100%. 3D dynamic MRA after RS may therefore be useful in association with MRI and can be repeated as long as opacification of the nidus or early venous drainage persists, one CCA remaining indispensable to affirm the complete occlusion at the end of follow-up.