Comparison of two high doses of oral methylprednisolone for multiple sclerosis relapses: a pilot, multicentre, randomized, double-blind, non-inferiority trial.

BACKGROUND AND PURPOSE: Oral or intravenous methylprednisolone (≥500 mg/day for 5 days) is recommended for multiple sclerosis (MS) relapses. Nonetheless, the optimal dose remains uncertain. We compared clinical and radiological effectiveness, safety and quality of life (QoL) of oral methylprednisolone [1250 mg/day (standard high dose)] versus 625 mg/day (lesser high dose), both for 3 days] in MS relapses. METHODS: A total of 49 patients with moderate to severe MS relapse within the previous 15 days were randomized in a pilot, double-blind, multicentre, non-inferiority trial (ClinicalTrial.gov, NCT01986998). The primary endpoint was non-inferiority of the lesser high dose by Expanded Disability Status Scale (EDSS) score improvement on day 30 (non-inferiority margin, 1 point). The secondary endpoints were EDSS score change on days 7 and 90, changes in T1 gadolinium-enhanced and new/enlarged T2 lesions on days 7 and 30, and safety and QoL results. RESULTS: The primary outcome was achieved [mean (95% confidence interval) EDSS score difference, -0.26 (-0.7 to 0.18) at 30 days (P = 0.246)]. The standard high dose yielded a superior EDSS score improvement on day 7 (P = 0.028). No differences were observed in EDSS score on day 90 (P = 0.352) or in the number of T1 gadolinium-enhanced or new/enlarged T2 lesions on day 7 (P = 0.401, 0.347) or day 30 (P = 0.349, 0.529). Safety and QoL were good at both doses. CONCLUSIONS: A lesser high-dose oral methylprednisolone regimen may not be inferior to the standard high dose in terms of clinical and radiological response.

Brainstem leukoaraiosis independently predicts poor outcome after ischemic stroke.

BACKGROUND AND PURPOSE: Increased supratentorial white matter hyperintensities volume (S-WMHV) has been reported to be a predictor of worse outcome in patients with acute ischemic stroke (AIS). However, few studies have focused on less common locations, such as brainstem white matter hyperintensities (B-WMH), and their relationship to S-WMHV. This study aimed to examine whether B-WMH affect clinical outcome after AIS or transient ischemic attack (TIA). METHODS: Based on magnetic resonance imaging evidence, B-WMH were evaluated in 313 prospectively identified patients with AIS/TIA and registered as absent or present. Standardized S-WMHV was quantified using a validated volumetric image analysis and natural log-transformed (Log_S-WMHV). Poor outcome was defined as a modified Rankin Scale score of 3-6 at 3 months after the index event. RESULTS: Brainstem white matter hyperintensities were detected in 57 (18.2%) patients. In unadjusted analyses for outcome, the presence of B-WMH was associated with worse outcome, compared with patients without B-WMH (P = 0.034). In multivariate analysis controlling for age, atrial fibrillation, stroke severity, reperfusion therapies and Log_S-WMHV, only B-WMH [odds ratio (OR), 2.46; P = 0.021] and stroke severity (OR, 1.23; P < 0.001) remained independently associated with unfavourable 90-day modified Rankin Scale score. Patients with B-WMH were older (OR, 1.06; P < 0.001) and tended to have more hyperlipidaemia (OR, 2.21; P = 0.023) and peripheral arterial disease (OR, 2.57; P = 0.031). CONCLUSIONS: Brainstem white matter hyperintensities are an independent predictor of poor outcome after AIS/TIA and this relationship persists after adjustment for important prognostic factors. Our results also show that leukoaraiosis in this location identifies patients with a specific risk factor profile, suggesting differences in the underlying pathogenesis.

Ultra-early hematoma growth in antithrombotic pretreated patients with intracerebral hemorrhage.

BACKGROUND AND PURPOSE: Patients with acute intracerebral hemorrhage (ICH) pretreated with antithrombotic drugs may have increased early hematoma growth, which would increase mortality risk. The effect of antiplatelet (AP) and vitamin K antagonist (VKA) pretreatment on ultra-early hematoma growth (uHG) and its relationship with mortality in patients with acute supratentorial ICH was analyzed. METHODS: This is an observational retrospective study of a prospective register of 197 ICH patients with first computed tomography (CT) scan taken <6 h from ICH symptom onset. ICH volume was calculated by the ABC/2 formula and uHG by the baseline ICH volume/onset-to-CT time (ml/h) formula. The uHG analysis took into account the patient's pretreatment (none, AP or VKA) and the relationship between uHG and very-early (first 24 h) and 3-month mortality. RESULTS: In the pretreatment group, 50 (25.4%) patients were treated with AP and 37 (18.8%) with VKA. The median (interquartile range 25-75) uHG was 19.7 ml/h (2.9-44.8) for AP pretreated patients, 16.2 ml/h (5.1-42.5) for VKA pretreated patients and 8.4 ml/h (2.4-21.8) for non-pretreated patients, P = 0.019. The uHG was higher in patients with very-early [42.1 ml/h (20.1-79.6)] and total 3-month mortality [28.0 ml/h (15.8-52.5)] compared with survivors [3.9 ml/h (1.5-10.4)], P < 0.0001. Adjusted by ICH severity and previous functional status, uHG was an independent factor related to very-early (P = 0.028) and total 3-month mortality (P = 0.014). CONCLUSIONS: Patients pretreated with antithrombotics have much higher uHG, which would explain the increased mortality in these patients compared to untreated patients.

Gadolinium-enhanced brain lesions in multiple sclerosis relapse.

OBJECTIVE: To study the clinico-radiological paradox in multiple sclerosis (MS) relapse by analyzing the number and location of gadolinium-enhanced (Gd+) lesions on brain MRI before methylprednisolone (MP) treatment. METHODS: We analyzed brain MRI from 90 relapsed MS patients in two Phase IV multicenter double-blind randomized clinical trials that showed the noninferiority of different routes and doses of MP administration. A 1.5- or 3-T brain MRI was performed at baseline before MP treatment and within 15 days of symptom onset. The number and location of Gd+ lesions were analyzed. Associations were studied using univariate analysis. RESULTS: Sixty-two percent of patients had at least 1 Gd+ brain lesion; the median number was 1 (interquartile range 0-4), and 41% of patients had 2 or more lesions. The most frequent location of Gd+ lesions was subcortical (41.4%). Gd+ brain lesions were found in 71.4% of patients with brainstem-cerebellum symptoms, 57.1% with spinal cord symptoms and 55.5% with optic neuritis (ON). Thirty percent of patients with brain symptoms did not have Gd+ lesions, and only 43.6% of patients had symptomatic Gd+ lesions. The univariate analysis showed a negative correlation between age and the number of Gd+ lesions (p=0.002). CONCLUSION: Most patients with relapse showed several Gd+ lesions on brain MRI, even when the clinical manifestation was outside of the brain. Our findings illustrate the clinico-radiological paradox in MS relapse and support the value of brain MRI in this scenario.

Wernicke encephalopathy: MR findings at clinical presentation in twenty-six alcoholic and nonalcoholic patients.

BACKGROUND AND PURPOSE: Wernicke encephalopathy is a severe neurologic disorder that results from a dietary vitamin B1 deficiency. It is characterized by changes in consciousness, ocular abnormalities, and ataxia. This study was undertaken to analyze and compare findings on MR imaging and neurologic symptoms at clinical presentations of patients with Wernicke encephalopathy with and without a history of alcohol abuse. MATERIALS AND METHODS: A multicenter study group retrospectively reviewed MR brain imaging findings, clinical histories, and presentations of 26 patients (14 female, 12 male) diagnosed between 1999 and 2006 with Wernicke encephalopathy. The age range was 6-81 years (mean age, 46 .6+/-19 years). RESULTS: Fifty percent of the patients had a history of alcohol abuse, and 50% had no history of alcohol abuse. Eighty percent showed changes in consciousness, 77% had ocular symptoms, and 54% had ataxia. Only 38% of the patients showed the classic triad of the disease at clinical presentation. At MR examination, 85% of the patients showed symmetric lesions in the medial thalami and the periventricular region of the third ventricle, 65% in the periaqueductal area, 58% in the mamillary bodies, 38% in the tectal plate, and 8% in the dorsal medulla. Contrast enhancement of the mamillary bodies was statistically positively correlated with the alcohol abuse group. CONCLUSIONS: Our study confirms the usefulness of MR in reaching a prompt diagnosis of Wernicke encephalopathy to avoid irreversible damage to brain tissue. Contrast enhancement in the mamillary bodies is a typical finding of the disease in the alcoholic population.

Clinical course of high-grade glioma patients with a "biopsy-only" surgical approach: a need for individualised treatment.

INTRODUCTION: 'Biopsy-only' high-grade glioma (HGG) patients get limited benefit from post-operative treatments, and as a group, negatively impact median survival outcomes. MATERIAL AND METHODS: We retrospectively evaluated clinical characteristics, treatment and overall survival of HGG patients with a 'biopsy- only' surgical approach diagnosed between 1997 and 2005 at a University Hospital in Spain. RESULTS: In 31% of 294 suspected gliomas, only a diagnostic biopsy was undertaken. Reasons for 'biopsy-only' for all patients were either location in eloquent areas: (motor area 18.7%, language area 25,3%, basal ganglia 7.7%, visual area 4.4%) or extension of the disease (corpus callosum invasion 14.3% and multicentricity/multifocality 28.6%). Seventy-four patients (80.4%) were HGG: 26% of all grade IV and 49% of all grade III tumours. For these patients, post-operative Karnofsky Performance Status of over 70%, median age and median survival were, respectively: 64 and 70%, 60.7 and 57 years old, and 23.1 and 42.7 weeks (p=0.0006). Patients lived longer if post-operative treatment was given, in all grades (p<0.0001). Nineteen patients (25.6%) died within 42 days after surgery. Only 60% of them initiated radiotherapy and 10% of them did not complete it. However, tumour grade, radiotherapy and temozolomide- based chemotherapy were independently associated with longer survival in multivariate analysis (p<0.05). CONCLUSION: Almost one third of HGG patients can undergo only a biopsy and not debulking surgery. Although radiotherapy improves survival, only 50% of them complete the treatment. An individualised approach to these patients is needed to facilitate a correct analysis of therapy results. New therapies must be investigated in these patients.

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.

Gadolinium-enhanced brain lesions in multiple sclerosis relapse / Lesiones cerebrales captantes de gadolinio en el brote de los pacientes con esclerosis múltiple

Objective: To study the clinico-radiological paradox in multiple sclerosis (MS) relapse by analyzing the number and location of gadolinium-enhanced (Gd+) lesions on brain MRI before methylprednisolone (MP) treatment. Methods: We analyzed brain MRI from 90 relapsed MS patients in two Phase IV multicenter double-blind randomized clinical trials that showed the noninferiority of different routes and doses of MP administration. A 1.5- or 3-T brain MRI was performed at baseline before MP treatment and within 15 days of symptom onset. The number and location of Gd+ lesions were analyzed. Associations were studied using univariate analysis. Results: Sixty-two percent of patients had at least 1 Gd+ brain lesion; the median number was 1 (interquartile range 0–4), and 41% of patients had 2 or more lesions. The most frequent location of Gd+ lesions was subcortical (41.4%). Gd+ brain lesions were found in 71.4% of patients with brainstem-cerebellum symptoms, 57.1% with spinal cord symptoms and 55.5% with optic neuritis (ON). Thirty percent of patients with brain symptoms did not have Gd+ lesions, and only 43.6% of patients had symptomatic Gd+ lesions. The univariate analysis showed a negative correlation between age and the number of Gd+ lesions (p = 0.002). Conclusion: Most patients with relapse showed several Gd+ lesions on brain MRI, even when the clinical manifestation was outside of the brain. Our findings illustrate the clinico-radiological paradox in MS relapse and support the value of brain MRI in this scenario. (AU)

Objetivo: Estudiar la paradoja clínico-radiológica en el brote de la esclerosis múltiple (EM) mediante el análisis de lesiones captantes de gadolinio (Gd+) en la RM cerebral antes del tratamiento con metilprednisolona (MP). Métodos: Analizamos la RM cerebral basal de 90 pacientes con EM en brote de 2 ensayos clínicos aleatorizados multicéntricos fase IV que demostraron la no inferioridad de diferentes vías y dosis de MP, realizadas antes del tratamiento con MP y en los 15 días siguientes a la aparición de los síntomas. Se analizaron el número y la localización de las lesiones Gd+. Se estudiaron las asociaciones mediante análisis univariado. Resultados: El 62% de los pacientes tenía al menos una lesión Gd+ cerebral y el 41% de los pacientes tenía 2 o más lesiones. La localización más frecuente fue la subcortical (41,4%). Se encontraron lesiones Gd+ cerebrales en el 71,4% de los pacientes con síntomas de tronco cerebral o cerebelo, en el 57,1% con síntomas medulares y en el 55,5% con neuritis óptica. El 30% de los pacientes con síntomas cerebrales no tenían lesiones Gd+ y sólo el 4,.6% de los pacientes tenían lesiones Gd+ sintomáticas. El análisis univariante mostró una correlación negativa entre la edad y el número de lesiones Gd+ (p = 0,002). Conclusiones: La mayoría de los pacientes en brote mostraron varias lesiones Gd+ en la RM cerebral, incluso cuando la manifestación clínica fue medular u óptica. Nuestros hallazgos ilustran la paradoja clínico-radiológica en el brote de la EM y apoyan el valor de la RM cerebral en este escenario. (AU)

A phase II study of feasibility and toxicity of bevacizumab in combination with temozolomide in patients with recurrent glioblastoma.

PURPOSE: The aim of this prospective and multicentric phase II study was to evaluate the efficacy and safety of temozolomide (TMZ) and bevacizumab (BV) in patients (pts) with recurrent glioblastoma (GB), previously treated with chemoradiotherapy and at least three cycles of adjuvant TMZ. PATIENTS AND METHODS: Patients with GB at first relapse received BV 10 mg/kg day every 2 weeks and TMZ 150 mg/m(2) days 1-7 and 15-21, every 28 days. Patients underwent brain magnetic resonance imaging every 8 weeks. RESULTS: Thirty-two evaluable pts were recruited in 8 sites. Fourteen pts (44%) had gross total resection. O(6)-methylguanine-DNA methyltransferase (MGMT) promoter was methylated in 12 pts, unmethylated in 6 pts, and missing in 14 pts. The estimated 6-month progression free survival (PFS) rate was 21.9% (95% CI 9.3-40.0%). The median PFS and overall survival (OS) were 4.2 months (95% CI 3.6-5.4 months) and 7.3 months (95% CI 5.8-8.8 months), respectively. No significant association with MGMT status was found in terms of OS or PFS. Six of 32 pts (19%; 95% CI 7.2-36.4) were long-term survivors, with a median PFS and OS (50% events) of 9.5 months (95% CI 7.9-23.6) and 15.4 (95% CI 8.9-NA), respectively: no differences in baseline characteristics were identified in comparison with total population. No unexpected toxicities or treatment-related deaths were observed. CONCLUSIONS: This regimen showed to be feasible and well tolerated in pts with recurrent GB pretreated with TMZ. Further investigation is warranted to identify subpopulations that are more likely to benefit from addition of BV to GB therapy.

31Phosphorus magnetic resonance spectroscopy in the assessment of head and neck tumors.

PURPOSE: 31Phosphorus magnetic resonance spectroscopy (31P-MRS) provides biochemical information in a noninvasive way. The aim of this work was: (a) to characterize the 31P spectrum of advanced head and neck tumors, and (b) to evaluate the spectral changes after treatment and to correlate them with the pathologic response. METHODS AND MATERIALS: A total of 20 patients diagnosed with advanced head and neck tumors and 7 healthy controls participated in the study. The tumor mass and its contralateral side were studied by means of 31P-MRS before and after treatment. Neck muscles of a control group were also studied. RESULTS: Tumors presented ratios of phosphomonoesters (PME), phosphodiesters (PDE), and inorganic phosphate (Pi) with respect to the adenosine triphosphate (ATP), significantly higher and a PCr (phosphocreatine)/ATP ratio lower than the neck muscle of volunteers or the contralateral side. The PDE/ATP and PME/ATP ratio values obtained before therapy were similar, independent of the later response to treatment. However, when there was a complete response, the ratios measured after treatment were decreased. CONCLUSION: These results show the existence of significant differences between the 31phosphorus spectrum of tumors and neck muscle, but also between the tumors and their contralateral sides. Moreover, 31P-MRS is able to detect metabolic changes after a complete response. These results suggest that 31P-MRS would be useful in the evaluation of the clinical response of head and neck tumors.

A multicenter proton magnetic resonance spectroscopy study of neurological complications of AIDS.

Human immunodeficiency virus (HIV) infection as seen in Europe and the United States has predominantly been contracted through male homosexual sex or intravenous drug abuse. In infected subjects, the brain is frequently affected both clinically and neuropathologically. The aim of this multicenter study has been to evaluate the value of single-voxel proton magnetic resonance spectroscopy (MRS) in the assessment of the neurological complications of acquired immunodeficiency syndrome (AIDS). MRS (voxel size = 8 ml, TR/TE = 1600/135 msec) was performed in 137 HIV-1-seropositive patients and 64 healthy controls without risk factors at three clinical MR sites operating at 1.5 T. The first result of this multicenter trial is that good reproducibility of results among participating sites was found. This demonstrates the reliability and robustness of MRS in the study of in vivo brain metabolism. In HIV patients, there was no significant correlation between metabolite ratios of brain detected by MRS and CDC grouping of patients or CD4 count. In contrast, the variations of brain metabolite ratios (NA/Cr, NA/Cho, and Cho/Cr) were related to the occurrence of encephalopathy, brain atrophy, or diffuse white matter lesions. There was no significant difference in brain metabolites between male homosexual AIDS patients and male intravenous drug user AIDS patients, whatever their neurological status (neurosymptomatic or neuroasymptomatic). Thus, the mode of transmission of HIV infection does not appear to affect the cerebral changes observed in the proton spectra from AIDS patients. Because of its ease of implementation and high information content, single-voxel proton MRS is likely to play a significant role in the evaluation of HIV-related encephalopathies.

Radiologic findings in two cases of acute Schmörl's nodes.

We describe two cases of atypical acute Schmörl's nodes, one benign, the other on a tumoral vertebra. In both cases, MR imaging showed a decreased vertebral T1 signal and a slightly increased T2 signal. These signal intensities are indistinguishable from tumoral disease or inflammatory lesions. The identification of endplate defects or intranuclear cleft bending of the disk by either CT or MR may be helpful for the correct diagnosis of acute Schmörl's nodes.

Lumbar extradural hemangiomas: report of three cases.

The CT, MR, and histologic findings of three patients with surgically proved lumbar extradural cavernous and arteriovenous hemangiomas are reported. All three patients suffered from radicular and low back pain that disappeared completely or nearly so after total surgical excision. In each case, neuroimaging studies showed a well-defined ventrally located extradural mass with no bone involvement. On MR images, all lesions were homogeneous and isointense on noncontrast T1-weighted images and hyperintense on T2-weighted images relative to the intervertebral disk. Homogeneous enhancement was seen in one of the two cases in which contrast-enhanced T1-weighted images were obtained. Purely extradural hemangiomas should be included in the differential diagnosis of lumbar extradural soft-tissue lesions. Features that may help to distinguish this entity from the more common extruded disk herniation or neurogenic tumors are its homogeneous high signal intensity on T2-weighted images, ovoid shape, and lack of anatomic relationship with the adjacent intervertebral disk or exiting nerve root.

Spontaneous ventriculostomy: report of three cases revealed by flow-sensitive phase-contrast cine MR imaging.

Spontaneous ventriculostomy is a rare condition that occurs with the spontaneous rupture of a ventricle, resulting in a communication between the ventricular system and the subarachnoid space. Three cases of spontaneous ventriculostomy through the floor of the third ventricle that occurred in cases of chronic obstructive hydrocephalus are presented. The communication was identified via flow-sensitive phase-contrast cine MR imaging. Spontaneous ventriculostomy is probably a result of a rupture of the normally thin membrane that forms the floor of the third ventricle and, with long-standing obstructive hydrocephalus, creates an internal drainage pathway that spontaneously compensates for the hydrocephalus.

Isolated demyelinating syndromes: comparison of different MR imaging criteria to predict conversion to clinically definite multiple sclerosis.

BACKGROUND AND PURPOSE: Various authors have developed criteria to classify MR imaging findings that suggest the possibility of multiple sclerosis. The purpose of this study was to evaluate and compare the capacity of three sets of MR imaging criteria for predicting the conversion of isolated demyelinating syndromes to clinically definite multiple sclerosis. METHODS: Seventy patients with clinically isolated neurologic symptoms suggestive of multiple sclerosis were prospectively studied with MR imaging. The MR imaging findings were evaluated by two independent neuroradiologists who were blinded to clinical follow-up data. Based on the clinical outcome at follow-up (presence of a second attack that established clinically definite multiple sclerosis), the sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of the criteria proposed by Paty et al, Fazekas et al, and Barkhof et al were calculated. RESULTS: Clinically definite multiple sclerosis developed in 22 (31%) patients after a mean follow-up time of 28.3 months. The criteria proposed by Paty et al and those proposed by Fazekas et al showed identical results: sensitivity, 86%; specificity, 54%; accuracy, 64%; positive predictive value, 46%; and negative predictive value, 89%. The criteria proposed by Barkhof et al showed the following: sensitivity, 73%; specificity, 73%; accuracy, 73%; positive predictive value, 55%; and negative predictive value, 85%. CONCLUSION: The four dichotomized MR imaging parameters proposed by Barkhof et al are more specific and accurate than the criteria proposed by Paty et al or Fazekas et al for predicting conversion to clinically definite multiple sclerosis.

Vertebral artery occlusion after acute cervical spine trauma.

STUDY DESIGN: A retrospective study of vertebral artery injury diagnosed during the last 6 years in our institution. OBJECTIVES: To determine the clinical and radiologic features of vertebral artery injury. SUMMARY OF BACKGROUND DATA: Extracranial occlusion of the vertebral artery associated with cervical spine fracture is uncommon and can cause serious and even fatal neurologic deficit due to back lifting and cerebellar infarction. Magnetic resonance imaging and magnetic resonance angiography are extremely helpful in the examination of acute injuries of the cervical spine. METHODS: Magnetic resonance imaging and magnetic resonance angiography were performed at the time of injury. RESULTS: The authors reviewed six patients with cervical spine fractures who were diagnosed with a unilateral occlusion of the vertebral artery by means of magnetic resonance imaging/magnetic resonance angiography. One patient had signs of vertebrobasilar insufficiency and another with complete cord lesion had cerebellar and back lifting infarctions. Surgical anterior spinal fusion was performed in five patients, and one was treated by traction and orthosis. At the time of discharge, five patients had no vertebrobasilar symptoms, and the patient who experienced vertebrobasilar territory infarctions showed no progression of the neurologic damage. CONCLUSIONS: Vertebral artery injury should be suspected in cervical trauma patients with facet joint dislocation or transverse foramen fracture. Magnetic resonance imaging/magnetic resonance angiography is a helpful test to rule out vascular injury. Vertebral artery injury affects the extracranial segment at the same level as the cervical fracture. This is a retrospective review that did not permit drawing conclusions about the effects of early surgical stabilization in the treatment of cervical spine injuries with associated vertebral artery injury; however, surgical stabilization may avoid propagation and embolization of the clot located at the site of the lesion.

Magnetic resonance anatomic study of iliocava junction and left iliac vein positions related to L5-S1 disc.

STUDY DESIGN: An in vivo anatomic study analyzing the venous anatomy in the lumbosacral area was performed. OBJECTIVES: To obtain in vivo data concerning iliocava junction and left common iliac vein positions at L5-S1. SUMMARY OF BACKGROUND DATA: The left common iliac vein and the iliocava junction are at risk during L5-S1 anterior lumbar interbody fusion. Anatomic studies have demonstrated great interindividual variability in this vascular anatomy. METHODS: Magnetic resonance angiography was used to study 134 patients. Image processing was carried out with maximum intensity projection algorithm and the maximum intensity projection and addition algorithm. Iliocava junction position was measured in the maximum intensity projection and addition image. Four groups of junction position were established: very high, high, low, and very low. The left common iliac vein position was measured in axial magnetic resonance images, and three groups were established: lateral, intermediate, and medial. To describe the operative window delimited by the venous structures at L5-S1, the study population was classified into 12 configurations by combining junction position and vein position values. RESULTS: Very high lateral included 3.76% of the patients, high lateral 48.12%, high intermediate 10.53%, high medial 0.75%, low lateral 15.04%, low intermediate 4.51%, low medial 6.77%, very low lateral 0.75%, very low intermediate 2.26%, and very low medial 7.52%. Medial vein position was significantly more frequent in men. CONCLUSIONS: In 18.05% of the study population, the venous structures overlapped the center of the L5-S1 disc, reducing the operative window.

Agreement between CSF flow dynamics in MRI and ICP monitoring in the diagnosis of normal pressure hydrocephalus. Sensitivity and specificity of CSF dynamics to predict outcome.

OBJECTIVES: The aims of the study were 1) to assess the degree of agreement between CSF flow dynamics determined by MR and ICP monitoring in the diagnosis of NPH, and 2) to determine the sensitivity and specificity of CSF flow dynamics studied by MR in predicting improvement after shunting. PATIENTS AND METHODS: A prospective study was carried out in 35 consecutive patients with suspected NPH. CSF velocity (Phase Contrast) through the aqueduct was determined in sagittal plane. Patients were classified as "normal" or hyperdynamic in comparison with a control group of 27 healthy volunteers. Continuous extradural ICP monitoring was performed for at least 72 hours and patients were classified as having active, compensated, or ex-vacuo hydrocephalus. Patients with active or compensated hydrocephalus were shunted. RESULTS: The degree of agreement between MR dynamics and ICP monitoring was 82%. Sensitivity of CSF velocity was 90% and specificity was 50%. CONCLUSIONS: The degree of agreement between ICP monitoring and CSF velocity is high. High CSF velocity through the aqueduct is a good predictor of improvement after surgery. However, patients with normal velocity in MR required additional tests before a diagnosis of NPH is ruled out.

[Cerebral proton spectroscopy of people infected with the human immunodeficiency virus]. / Espectroscopia de protón en el cerebro de personas infectadas por el virus de la inmunodeficiencia humana.

BACKGROUND: This article presents a combined magnetic resonance imaging and proton spectroscopy protocol (MRI/1H-MRS) applied to study the brain of human immunodeficiency virus (HIV) infected patients. The spectroscopic results were compared with clinical and radiological parameters. PATIENTS AND METHODS: The proton spectra of 57 HIV patients and 20 control subjects were obtained from a volume of interest of 8 cm3 located in the parietooccipital region of the brain that did not include any focal lesion. The resonance areas due to N-acetyl aspartate (NAA), creatine (Cr) and choline (Cho) were obtained. The MRI exam allowed us to determine the presence of focal or diffuse lesions and the degree of atrophy. Finally, the clinical exploration included the performance of a Mini-Mental test. The NAA/Cr, NAA/Cho and Cho/Cr ratios were correlated with clinical characteristics, the result of the Mini-Mental test, the presence of lesions and the degree of atrophy. RESULTS: There were altered spectral patterns in a volume of the brain that did not contain any focal lesion. The decrease in the NAA/Cr or NAA/Cho ratios was significative when considering the presence of atrophy, the existence of signs of cognitive deficiencies or the diagnosis of AIDS-dementia complex. CONCLUSIONS: The spectral changes found in the present study suggest the existence of neuronal lesions that would be due to the HIV-infection. A combined MRI/1H-MRS study may provide a more complete information about the neurological impairment by HIV and could constitute a marker of AIDS-dementia complex.

[Diffusion-weighted magnetic resonance in the diagnosis of acute subcortical infarcts]. / Difusión por resonancia magnética en el diagnóstico de los infartos subcorticales agudos.

INTRODUCTION: The diagnostic efficacy of radiological studies in acute subcortical infarcts is limited by the low sensitivity of conventional computerized tomography (CT) and magnetic resonance (MR) in detecting small-sized infarcts, and the difficulty in differentiating acute from chronic lesions. Diffusion-weighted MR (DMR) has shown great sensitivity and specificity in the detection of small vessel ischemic lesions during the acute phase. OBJECTIVE: To determine the diagnostic value of DMR in the study of patients with subcortical infarcts during the acute phase. PATIENTS AND METHODS: We made a prospective analysis of 100 consecutive patients with a clinical diagnosis of subcortical infarct. In all cases MR examination was done within the first 10 days (average 3.9 days) following onset, using conventional and diffusion-weighted sequences. RESULTS: In all cases the DMR showed the presence of ischemic lesions which explained, at least partly, the clinical features of the stroke. In 42 patients (42%) the DMR gave relevant information for diagnosis, as compared with the conventional MR studies, by confirming the presence of an ischemic lesion responsible for the clinical picture. The percentage rose to 50% when the examination was done within the first two days. CONCLUSIONS: DMR gives useful information in a high percentage of patients with acute subcortical infarcts. This is due to its great sensitivity in the detection of acute lesions of small size, and capacity to distinguish acute from chronic lesions.