Anterior ischemic stroke: Comparison of two clinical outcome prediction scores through the investigation of cerebral collaterals using multiphase CT angiography.

PURPOSE: To compare the evaluation of collaterals on multiphase computed tomography (CT) angiography using the score proposed by the reference study by Menon et al. and the Alberta Stroke Program Early CT (ASPECT) score for the prediction of favorable clinical outcome in patients with anterior ischemic stroke (IS). MATERIALS AND METHODS: Retrospective single center study including 199 patients with anterior ischemic stroke and evaluated using multiphase CT angiography. Collaterals were assessed using the reference score and ASPECT score. The early clinical outcome [National Institute of Health Stroke Score (NIHSS) over day 1] and later clinical outcome [90-day modified Rankin Scale (mRS)] were collected. The primary analysis related to the association between collateral scores and clinical outcome. RESULTS: Collaterals are an independent predictive factor of favorable clinical outcome with the two scores, ranging from an odds ratio (OR) [95% confidence interval (CI)] = 1.84 [1.23; 2.76], P = 0.003 for the reference score to an OR [95% CI] = 2.63 [1.21; 5.73], p = 0.015 for the phase 3 ASPECT score. The phase 3 ASPECT score offers better sensitivity (Se) for the prediction of a favorable clinical outcome [Se = 95%, specificity (Sp) = 37% for a threshold of 7/7] than the reference score (Se = 83%, Sp = 47% for a threshold of 4/5). CONCLUSION: This study demonstrates the value of the ASPECT score in analyzing collaterals using multiphase CT angiography for the prediction of clinical outcome.

Personalized mapping of the deep brain with a white matter attenuated inversion recovery (WAIR) sequence at 1.5-tesla: Experience based on a series of 156 patients.

OBJECTIVE: Deep brain mapping has been proposed for direct targeting in stereotactic functional surgery, aiming to personalize electrode implantation according to individual MRI anatomy without atlas or statistical template. We report our clinical experience of direct targeting in a series of 156 patients operated on using a dedicated Inversion Recovery Turbo Spin Echo sequence at 1.5-tesla, called White Matter Attenuated Inversion Recovery (WAIR). METHODS: After manual contouring of all pertinent structures and 3D planning of trajectories, 312 DBS electrodes were implanted. Detailed anatomy of close neighbouring structures, whether gray nuclei or white matter regions, was identified during each planning procedure. We gathered the experience of these 312 deep brain mappings and elaborated consistent procedures of anatomical MRI mapping for pallidal, subthalamic and ventral thalamic regions. We studied the number of times the central track anatomically optimized was selected for implantation of definitive electrodes. RESULTS: WAIR sequence provided high-quality images of most common functional targets, successfully used for pure direct stereotactic targeting: the central track corresponding to the optimized primary anatomical trajectory was chosen for implantation of definitive electrodes in 90.38%. CONCLUSION: WAIR sequence is anatomically reliable, enabling precise deep brain mapping and direct stereotactic targeting under routine clinical conditions.

[Radiology of central nervous system cavernomas]. / Imagerie des cavernomes du système nerveux central.

MRI is the best radiological technique to explore cavernomas, vascular malformations affecting the entire central nervous system. The presence of blood degradation products produces a specific aspect which enables excellent contrast resolution. Certain diagnosis can be established with MRI which can also be used to follow growth and modifications, particularly in familial forms. In the emergency setting, the first exam is often a CT-scan for patients presenting acute neurological sign(s) and/or with a clinical suspicion of hemorrhagic stroke. Angiography is generally not contributive because cavernomas are occult vascular malformations. Nevertheless, this exam is often necessary when an associated vascular abnormality is suspected, particularly a developmental venous abnormality.

[Electronic imaging with photo-realistic rendering for neuroanatomy teaching. Methods and preliminary results]. / Imagerie électronique en rendu photo-réaliste pour l'enseignement de la Neuro-anatomie. Méthodes et résultats.

Advances in software, networking, and imaging technology provide a unique opportunity for developing information systems in anatomy that can deliver relevant knowledge to the clinicians, researchers, educators, and students. Recent software tools initially produced for graphic imaging are now available in the medical graphic design field. The authors describe an original method they used to create electronic images of the central nervous system and its coverings with photo-realistic rendering. They present preliminary results and discuss the potential of this new technique as a teaching tool for neuroanatomy.

Acute nontraumatic spinal subdural hematomas in three patients.

STUDY DESIGN: The clinical data, magnetic resonance imaging, intraoperative findings, and functional outcome were reviewed for three patients under anticoagulant therapy who experienced acute nontraumatic spinal subdural hematoma. OBJECTIVES: To draw attention to this rare complication of anticoagulant therapy and to assess the magnetic resonance findings and clinical outcome of patients with spinal subdural hematoma after surgical evacuation. SUMMARY OF BACKGROUND DATA: Among intraspinal hematomas, spinal subdural hematomas are by far the least common. Magnetic resonance findings have been demonstrated in only a few cases of spinal subdural hematomas. The timing of the operation and the anatomic location of the hematoma essentially determine the functional outcome. METHODS: Three case reports of spinal subdural hematomas in patients receiving anticoagulant therapy are presented. Particular interest was given to the clinical and magnetic resonance data, the intraoperative findings, and the functional outcome. RESULTS: The three patients each had a complete preoperative neurologic deficit. Sagittal T1- and T2-weighted magnetic resonance images of the spine proved to have high sensitivity for defining the type of bleeding and delineating the craniocaudal extension of the hematoma. Surgical evacuation was performed within 26 hours after the onset of symptoms. Intraoperative findings showed the hematoma to be confined between the dura and the arachnoid in two patients, and to be associated with rupture into the subarachnoid space in one patient. Postoperative recovery was incomplete in two patients, and did not improve in the remaining patient. CONCLUSIONS: Spinal subdural hematoma must be considered in patients under anticoagulant therapy with spontaneous signs of acute spinal cord or cauda equina compression. Magnetic resonance imaging with sagittal T1- and T2-weighted images were adequate and reliable for diagnosis of spinal subdural hematoma. On the basis of previous studies and the authors' intraoperative findings, spinal subdural hematomas could be viewed as spinal dural border hematomas. The level of preoperative neurologic deficit seemed to be critical for recovery despite prompt surgical evacuation.

Spinal epidural angiolipoma.

Spinal epidural angiolipoma is a rare benign tumor predominantly located in the mid-thoracic region. The authors report a case of spinal epidural angiolipoma in a 36-year old woman who presented with subacute paraplegia. Clinico-pathological and MRI findings of this uncommon tumor are discussed.

Spontaneous chronic spinal epidural hematoma of the lumbar spine.

We report an exceptional description of a spontaneous chronic spinal epidural hematoma presenting as lumbar radiculitis. The computed tomographic, magnetic resonance imaging, and intraoperative findings are presented. We discuss anatomical and pathophysiological considerations that could lead to such a condition. We estimate that spontaneous spinal epidural hematomas located in the ventral space are in fact premembranous or posterior longitudinal ligament hematomas.

[A case of giant craniopharyngioma in an adult]. / Un cas de craniopharyngiome géant chez l'adulte.

We report an unusual case of giant adamantinomatous craniopharyngioma in an adult who presented with impaired vision. The intra- and suprasellar tumor extended into the subfrontal, subtemporal and retroclival regions. CT and MRI allowed diagnosis and optimal surgical planning.

Rathke's cleft cysts: surgical-MRI correlation in 16 symptomatic cases.

Rathke's cleft cysts (RCCs) are non neoplastic epithelial lesions of the sellar region that have been rarely reported as a clinical entity. We retrospectively reviewed the magnetic resonance imaging (MRI), intraoperative, and pathological findings of a series of 16 cases of RCCs operated at our institution since 1992. Concurrently, we discussed the different hypotheses about their embryological origin. The patients included 12 females and 4 males, 11 to 73 years of age. Endocrine disturbance was the most common presentation, followed by headaches and visual impairment. The location of the cyst was intrasellar in 7 cases, intrasellar and suprasellar in 6 cases, and suprasellar in 3 cases. The size of the cyst ranged from 8 to 26 mm (mean 12 mm). MRI signal intensity was quite variable on T1-weighted images. The cyst appeared hyperintense in 6 cases, hypointense in 6 cases, isointence in 3 cases, and heterogeneous in one case. On T2-weighted images (available in 13 cases), the signal intensity was more constant and appeared hyperintense in 11 cases and hypointense in 2 cases. After Gd-DTPA, we did not observe enhancement either of the cyst contents or of the cyst wall, but only of the pituitary gland in all patient. Most often, the pituitary gland was displaced inferiorly by the cyst located above showing a typical image of "an egg in a cup". Fifteen patients were operated upon via the transsphenoidal approach and one upon a frontal craniotomy. Intraoperatively, the cyst contents were gelatinous or thick, and dark colored. In 2 cases, it was cerebrospinal fluid-like corresponding to the signal observed on MRI. The position of the pituitary gland confirmed by surgery in 15 cases coincided with enhancement seen and MR imaging. In 13 cases where biopsy of the cyst wall was performed, it confirmed focally ciliated columnar or cuboid epithelium. A coexistent adenoma was found in one case. In conclusion, we consider that RCCs have varied MRI characteristics so that no pathognomonic sign may be observed. Except in few cases, there were no correlation between MRI and intraoperative findings. Therefore, even with MRI studies, differential diagnoses with others cystic lesions of the sellar region remains extremely difficult. The most interesting findings on MRI studies of RCCs were to locate the pituitary gland to help the surgeon to preserve pituitary tissue during surgery.

Intramedullary cavernous malformations.

Five cases of intramedullary cavernous malformations were retrospectively reviewed. There were 4 women and one man ranging in age from 30 to 67 years. Thoracic spinal cord was involved twice and cervical cord in three cases. Four of them underwent surgery: two improved, one remained stable and symptoms worsened in one. Clinical, radiological features and surgical management are discussed in the light of the follow-up and literature analysis. The role of T2* weighted sequence in MR diagnosis of intramedullary cavernomas is emphasised.

Analysis of cerebrovascular diseases by a new 3-dimensional computerised X-ray angiography system.

We set out to validate the concept of three-dimensional (3D) angiography. We evaluated the sensitivity and the quality of morphological analysis mode possible by an experimental system for imaging cerebrovascular disease versus standard digital subtraction angiography (DSA). The system, the 3D Morphometer, is a computerised X-ray angiography unit capable of acquiring a set of two-dimensional (2D) projections during a rotation and then reconstructing a 3D volume from them. We studied 78 patients with suspected cerebrovascular disease. 3D and 2D images (standard 2D DSA performed during the same procedure), were reviewed blindly to assess detection and display of morphological characteristics of cerebrovascular diseases. We found 53 aneurysms, 22 arteriovenous malformations and two venous angiomas. On 3D angiography we detected two aneurysms we missed on 2D angiography. In 47 aneurysms on which further data were obtained during surgery or embolisation, the 3D angiography allowed more accurate analysis of the neck and surrounding vessels in cases in which the 2D angiographic findings were doubtful. Assessment of arteriovenous malformations was equivalent with both techniques. Under the conditions of our study, the technical constraints being the same for both methods, 3D angiography was superior to 2D angiography. Implementation on C-arm vascular systems is being evaluated.

[The role of 3-dimensional reconstructions in the angiographic evaluation of cerebral vascular malformations: 3D morphometry]. / Place des reconstructions tri-dimensionnelles dans le bilan angiographique des malformations vasculaires cérébrales: le morphomètre 3D.

The need for medical images which can directly contribute to therapeutic decision making has led to the development of 3D visualization techniques. With this objective, a procedure capable of producing 3D volume reconstructions using isotropic voxels from digitalized 2D films obtained by rotation around the object has been developed: 3D morphometry. The technique has been assessed from 1993 through 1996 for vascular malformations in the brain, particularly aneurysms. Recognition of collateral vessels originating at the malformation was helpful in better identifying the lesions and evaluating possible therapeutic difficulties. The morphometric sequence thus is a possibility for the future assessment of neurovascular arches.