Diffuse Large B-Cell Epstein-Barr Virus-Positive Primary CNS Lymphoma in Non-AIDS Patients: High Diagnostic Accuracy of DSC Perfusion Metrics.

BACKGROUND AND PURPOSE: Immunodeficiency-associated CNS lymphoma may occur in different clinical scenarios beyond AIDS. This subtype of CNS lymphoma is diffuse large B-cell and Epstein-Barr virus-positive. Its accurate presurgical diagnosis is often unfeasible because it appears as ring-enhancing lesions mimicking glioblastoma or metastasis. In this article, we describe clinicoradiologic features and test the performance of DSC-PWI metrics for presurgical identification. MATERIALS AND METHODS: Patients without AIDS with histologically confirmed diffuse large B-cell Epstein-Barr virus-positive primary CNS lymphoma (December 2010 to January 2022) and diagnostic MR imaging without onco-specific treatment were retrospectively studied. Clinical, demographic, and conventional imaging data were reviewed. Previously published DSC-PWI time-intensity curve analysis methodology, to presurgically identify primary CNS lymphoma, was used in this particular lymphoma subtype and compared with a prior cohort of 33 patients with Epstein-Barr virus-negative CNS lymphoma, 35 with glioblastoma, and 36 with metastasis data. Normalized curves were analyzed and compared on a point-by-point basis, and previously published classifiers were tested. The standard percentage of signal recovery and CBV values were also evaluated. RESULTS: Seven patients with Epstein-Barr virus-positive primary CNS lymphoma were included in the study. DSC-PWI normalized time-intensity curve analysis performed the best for presurgical identification of Epstein-Barr virus-positive CNS lymphoma (area under the receiver operating characteristic curve of 0.984 for glioblastoma and 0.898 for metastasis), followed by the percentage of signal recovery (0.833 and 0.873) and CBV (0.855 and 0.687). CONCLUSIONS: When a necrotic tumor is found in a potentially immunocompromised host, neuroradiologists should consider Epstein-Barr virus-positive CNS lymphoma. DSC-PWI could be very useful for presurgical characterization, with especially strong performance of normalized time-intensity curves.

Presurgical Identification of Primary Central Nervous System Lymphoma with Normalized Time-Intensity Curve: A Pilot Study of a New Method to Analyze DSC-PWI.

BACKGROUND AND PURPOSE: DSC-PWI has demonstrated promising results in the presurgical diagnosis of brain tumors. While most studies analyze specific parameters derived from time-intensity curves, very few have directly analyzed the whole curves. The aims of this study were the following: 1) to design a new method of postprocessing time-intensity curves, which renders normalized curves, and 2) to test its feasibility and performance on the diagnosis of primary central nervous system lymphoma. MATERIALS AND METHODS: Diagnostic MR imaging of patients with histologically confirmed primary central nervous system lymphoma were retrospectively reviewed. Correlative cases of glioblastoma, anaplastic astrocytoma, metastasis, and meningioma, matched by date and number, were retrieved for comparison. Time-intensity curves of enhancing tumor and normal-appearing white matter were obtained for each case. Enhancing tumor curves were normalized relative to normal-appearing white matter. We performed pair-wise comparisons for primary central nervous system lymphoma against the other tumor type. The best discriminatory time points of the curves were obtained through a stepwise selection. Logistic binary regression was applied to obtain prediction models. The generated algorithms were applied in a test subset. RESULTS: A total of 233 patients were included in the study: 47 primary central nervous system lymphomas, 48 glioblastomas, 39 anaplastic astrocytomas, 49 metastases, and 50 meningiomas. The classifiers satisfactorily performed all bilateral comparisons in the test subset (primary central nervous system lymphoma versus glioblastoma, area under the curve = 0.96 and accuracy = 93%; versus anaplastic astrocytoma, 0.83 and 71%; versus metastases, 0.95 and 93%; versus meningioma, 0.93 and 96%). CONCLUSIONS: The proposed method for DSC-PWI time-intensity curve normalization renders comparable curves beyond technical and patient variability. Normalized time-intensity curves performed satisfactorily for the presurgical identification of primary central nervous system lymphoma.

Seizure-susceptible brain regions in glioblastoma: identification of patients at risk.

BACKGROUND AND PURPOSE: The main aim of this study was to identify which patients with glioblastoma multiforme (GBM) have a higher risk of presenting seizures during follow-up. METHODS: Patients with newly diagnosed GBM were reviewed (n = 306) and classified as patients with (Group 1) and without (Group 2) seizures at onset. Group 2 was split into patients with seizures during follow-up (Group 2A) and patients who never had seizures (Group 2B). The anatomical location of GBM was identified and compared by voxel-based lesion symptom mapping (discovery set). Seizure-susceptible brain regions obtained were assessed visually and automatically in external GBM validation series (n = 85). RESULTS: In patients with GBM who had no seizures at onset, an increased risk of presenting seizures during follow-up was identified in the superior frontal and inferior occipital lobe, as well as in inferoposterior regions of the temporal lobe. Conversely, those patients with GBM located in medial and inferoanterior temporal areas had a significantly lower risk of suffering from seizures during follow-up. Additionally, the seizure-susceptible brain region maps obtained classified patients in the validation set with high positive and negative predictive values. CONCLUSIONS: Tumor location is a useful marker to identify patients with GBM who are at risk of suffering from seizures during follow-up. These results may help to support the use of antiepileptic prophylaxis in a selected GBM population and to improve stratification in antiepileptic clinical trials.

Results of a multicenter survey showing interindividual variability among neurosurgeons when deciding on the radicality of surgical resection in glioblastoma highlight the need for more objective guidelines.

PURPOSE: We assessed agreement among neurosurgeons on surgical approaches to individual glioblastoma patients and between their approach and those recommended by the topographical staging system described by Shinoda. METHODS: Five neurosurgeons were provided with pre-surgical MRIs of 76 patients. They selected the surgical approach [biopsy, partial resection, or gross total resection (GTR)] that they would recommend for each patient. They were blinded to each other's response and they were told that patients were younger than 50 years old and without symptoms. Three neuroradiologists classified each case according to the Shinoda staging system. RESULTS: Biopsy was recommended in 35.5-82.9%, partial resection in 6.6-32.9%, and GTR in 3.9-31.6% of cases. Agreement among their responses was fair (global kappa = 0.28). Nineteen patients were classified as stage I, 14 as stage II, and 43 as stage III. Agreement between the neurosurgeons and the recommendations of the staging system was poor for stage I (kappa = 0.14) and stage II (kappa = 0.02) and fair for stage III patients (kappa = 0.29). An individual analysis revealed that in contrast to the Shinoda system, neurosurgeons took into account T2/FLAIR sequences and gave greater weight to the involvement of eloquent areas. CONCLUSIONS: The surgical approach to glioblastoma is highly variable. A staging system could be used to examine the impact of extent of resection, monitor post-operative complications, and stratify patients in clinical trials. Our findings suggest that the Shinoda staging system could be improved by including T2/FLAIR sequences and a more adequate weighting of eloquent areas.

Combination of corpus callosotomy and vagus nerve stimulation in the treatment of refractory epilepsy.

BACKGROUND: Palliative techniques such as partial corpus callosotomy (CC) and vagus nerve stimulation (VNS) may be effective for adequate control of seizures in pharmacoresistant patients who are not candidates for resective surgery. OBJECTIVE: The objective of this study was to analyze the efficacy of the combination of these two techniques in patients where the first surgery had not achieved adequate control. MATERIALS AND METHODS: This is a retrospective review of 6 patients with refractory epilepsy in which both types of surgery were performed, CC and VNS. We analyzed variables such as age, sex, age at onset of epilepsy, seizure types, electroencephalogram and magnetic resonance imaging results, and number of pre- and postoperative seizures. RESULTS: Three patients first underwent VNS and then CC, and 3 patients were treated in reverse order. All patients had some improvement after the first surgery, but they continued to experience persistent falls, so a second palliative technique was used. The mean improvement after both surgeries was 89% (90% in patients first receiving CC and 87% in patients who first underwent VNS). CONCLUSIONS: In adequately studied patients who are not optimal candidates for resective surgery, palliative surgery is a choice. The combination of VNS and CC shows good results in our series, although the right order to perform both procedures has not been defined. These results should be confirmed in a larger group of patients.

[Posterior spinal instrumentation image guided and assisted by neuronavigation. Experience in 120 cases]. / Fijación vertebral posterior guiada por neuronavegación. Experiencia en 121 casos.

INTRODUCTION: The authors present the results of a series of 121 cases of posterior vertebral fixation carried out from Sept 2008 to Sept 2010 using Flouro 2D-TC assisted Vector Vision o Kolibri navigator. ( Brain LAB, Feldkirchen, Germany). MATERIAL: The sample included 68 males and 53 females. Age range was 24-75 with an average of 50.35., all with indication for instrumentation by different pathologies. METHOD: Patients presenting vertebral lesions of varying ethiology and lesion level with vertebral posterior fixation indication were included in the study. All underwent a CT before surgery, according to navigation protocol, and the images obtained were merged in the navigator with those obtained in the operating room with a Flouro 2D, which allowed a high quality 3D reconstruction to be performed and thus the capacity to navigate in a real-virtual manner. To evaluate the results of the implant a post-op CT was performed and the position of the implant was defined according to the Heary scale. The calabration time of the material was also evaluated, number of shots with the Flouro-2D, and for clinical evaluation VAS scales were employed, Oswestry and JOA (L), as well as the degree of satisfaction and acceptance of the procedure. RESULTS: A total of 580 screws were implanted, distributed in 62 cervicals of which 24 were in C1-C2, 38 dorsals, 370 lumbar and 110 sacral. Open surgery was performed in 42 cases, MIS in 28 and percutaneous in 51. The presision of the implant was 98.45% with a global deviation of 1.55%, that according to the Heary scale was distributed in grade ll: 2 (1 cervical, 1 lumbar) grade lll: 4 (1 cervical, 2 dorsal, 1 lumbar), grade IV: 3 (1 cervical, 2 lumbar). General average time of calibration per procedure was 2 min. 49 seconds and the mean flouroscopic exposure was one shot at cervical and dorsal and two shots at lumbar level. The clinical evaluation at one month of 121 patients was 8.6/3.0 in the VAS, 68.0% / 23.0% in Oswestry and 6.4/13.1 in JOA (L), with those parameters remaining stable at 3 months in 100 and at 6 months in 87 patients respectively, and the degree of satisfaction between being completely and very satisfied with the procedure was 94.9%, and those who would submit to another treatment was more than 94%. CONCLUSION: Navigation with Flouro-2D-CT is a high precision technique that reduces complications of varying severity according to the level operated well as number of reinterventions, radiation exposure and surgical time.

[Intraoperative identification of the supplementary motor area in neurooncological surgery]. / Identificación intraoperatoria del área motora suplentaria en cirugía neurooncológica.

OBJECTIVES: The main objective of the present work was to identify, by means of intraoperative electrical stimulation, the supplementary motor area (SMA) region which is implicated in complex motor function. The functional prognostic relevance of the surgical preservation of this area was also analyzed. METHOD: Fifteen patients with tumors infiltrating the premotor cortex were selected. All patients were operated under awake conditions. Primary motor cortex was identified with intraoperative electrical stimulation (IES). To identify the SMA, patients were asked to do a finger opposition motor task with their hand contralateral to the lesion, that was blocked by electrically stimulating the premotor cerebral cortex. RESULTS: SMA was identified in all patients with IES. Complete surgical resection was achieved in 13 patients (86.6%) and subtotal in 2 patients (13.3%). SMA function was preserved in 14 patients (93.3%). In only one patient the SMA was partially resected because of tumor infiltration (6.6%). In the immediate postoperative period, 8 patients (53.3%) did not show changes in comparison to their preoperative clinical status, and 2 patients improved. At 6 months follow up, 5 patients (33.3%) were asymptomatic and 10 patients showed permanent deficits. In this last group, five patients (33.3%) showed mild deficits that did not interfere with a normal life. In the other 5 patients (33.3%), permanent deficits interfered with daily life activities: two patients presented severe hemiparesis 3/5 (same similar to their preoperative status with no improvement), one patient had motor aphasia, and two other patients (13.3%) showed permanent left SMA syndrome. In two patients with severe postoperative hemiparesis, tumor infiltration of primary motor cortex and piramidal pathway was observed; severe preoperative motor deficit (KPS <70) was associated with poor functional outcome. CONCLUSIONS: Intraoperative electrical cortical stimulation is useful to identify the SMA. Once identified, SMA preservation decreases the risk of postoperative symptoms and permanent SMA syndrome. When SMA is infiltrated by the tumor, radical resection may cause permanent neurological deficits, specially in the dominant hemisphere. Severe preoperative motor deficit was associated with poor outcome.

Intracranial retrograde dissemination in filum terminale myxopapillary ependymomas.

Myxopapillary ependymomas (ME) are considered benign tumours (WHO grade I) of the central nervous system with long term survival rates and a tendency to local recurrence. However an aggressive course has occasionally been described, leading to CSF dissemination and even systemic metastases. We describe the case of a 23-year-old man diagnosed with intracranial subarachnoid dissemination of a filum terminale ME three years after the initial diagnosis. We have performed a careful review of the literature on CSF dissemination in ME and finally propose treatment of these cases.

[Spinal epidural hematomas. Prognostic factors in a series of 22 cases and a proposal for management]. / Revisión de 22 casos de hematomas epidurales espinales. Factores pronósticos y manejo terapéutico.

INTRODUCTION: Spontaneous and non-spontaneous spinal epidural hematoma (SEH) is a rare condition in neurosurgical practice. It presents as an acute spinal cord compression and usually requires emergent surgical decompression. Recently non-surgical treatment (corticoid therapy) has been proposed in selected cases of SEH with good neurological recovery. OBJECTIVES: To identify the prognostic factors of this condition. A treatment management based upon our results is proposed. MATERIAL AND METHODS: Between 1985 and 2001, 22 patients suffering SEH were treated at our Department. Age, sex, initial neurological condition (evaluated using the Frankel grading scale), surgical timing, radiological data such as location, extension and degree of radiological cord compression, anticoagulation or antiplatelet therapy, epidural anesthesia and previous spinal surgery were analyzed in order to find prognostic factors. Finally, conservative or surgical treatment as well as final neurological condition were also considered for the analysis. RESULTS: The average age was 69 years with a male preponderance (72.7%). Surgical decompression was done in 17 cases, most of them (11 cases) presenting with high neurological deficit (Frankel A-B). Conservative treatment was used on 5 patients. Operated patients showed a larger degree of neurological recovery. The incidence of post-operative complications was of 13%. CONCLUSIONS: This study shows the efficiency of SEH surgical evacuation performed within the first 24 hours, particularly when the patient presents a severe neurological deficit (Frankel A-B). Patients presenting minimal neurological involvement (Frankel D-E) can be managed successfully with conservative treatment.