MR imaging features of brain stem hypoplasia in familial horizontal gaze palsy and scoliosis.

We report the case of a child with horizontal gaze palsy, pendular nystagmus, and discrete thoracolumbar scoliosis. MR imaging of the brain depicted pons hypoplasia with an absence of the facial colliculi, hypoplasia, butterfly configuration of the medulla, and the presence of a deep midline pontine cleft (split pons sign). These MR imaging findings suggest familial horizontal gaze palsy with progressive kyphoscoliosis, a rare congenital disorder. To the best of our knowledge, MR imaging findings of only 4 similar cases, with or without progressive idiopathic scoliosis, have been reported. We discuss the pathogenesis substratum of this entity. Early recognition of this rare entity is important if supportive therapeutic measures in progressive scoliosis are to be applied.

Differential diagnosis of mesiotemporal lesions: case report of neurosyphilis.

We report a clinical and imaging case of suspected herpes simplex encephalitis subsequently diagnosed as neurosyphilis based on positive antibodies in the CSF. MRI of the brain showed cortical and subcortical lesions in the mesial temporal region, septal area, insula and cingulated gyrus of the right cerebral hemisphere. Neurosyphilis should be included in the differential diagnosis of mesial temporal region lesions on MRI.

Small-cell carcinoma of the lung resembling a brachial plexus tumour.

A small-cell carcinoma of the lung was identified in a six-year-old female German shepherd dog with a history of chronic lameness of the left forelimb, Horner's syndrome and sensory deficits on the caudal portion of the left forelimb below the elbow. A mass, the exact location of which was difficult to ascertain, was identified during radiographic examination of the thorax. It was easily identified, using magnetic resonance imaging, as an apical tumour of the left lung with dorsal extension and involvement of paraspinal structures, such as spinal nerve roots C8 to T1 and the sympathetic trunk. Postmortem examination confirmed a mass in the left apical lobe of the lung, compatible with a diagnosis of small-cell carcinoma by histopathology and immunohistochemistry. This clinical presentation is similar to Pancoast syndrome described in humans.

Intracranial angiolipoma as cause of subarachnoid haemorrhage. Case report and review of the literature.

A 33-year-old female with a longstanding history of seizures was admitted to our hospital with subarachnoid haemorrhage (SAH). Computed tomography (CT), magnetic resonance imaging (MRI) and digital subtraction angiography (DSA) depicted a vascular fat-containing lesion overlying a right frontal cortical polymicrogyria. The diagnosis of angiolipoma was established. Conservatory management was undertaken with full recovery. She has been followed for 5 years since, with neither re-bleeding nor morphologic change of the lesion. This is a rare intracranial lesion, with only 11 intracranial angiolipomas published in the literature, and is the first case reported which is associated with SAH caused by this lesion.

Ischemic stroke: carotid and vertebral artery disease.

Ischemic strokes may have distinct aetiologies, including several different intrinsic arterial pathological disorders. The diagnosis and understanding of these arterial diseases is critical for the correct management of stroke as different treatment approaches are undertaken according to the aetiology. Atherosclerosis is by far the most common arterial disease among adults, and other pathological processes include arterial dissection, small vessel disease, inflammatory and non-inflammatory vasculopathy and vasomotor disorders. In children, there are several vasculopathies responsible for vaso-occlusive disease such as sickle-cell anemia, acute regressive angiopathy and Moya-Moya disease, neurofibromatosis, dissections, vasculitis associated with intracranial and systemic infections. An overview of the major carotid and vertebral pathological diseases responsible for ischemic stroke in adults and children, highlighting the accuracy of the different imaging modalities for its diagnosis and the imaging appearance of these diseases, is given.

Endovascular Pressure Measurements: Validation with a Pulsatile Flow Model and Haemodynamic Assessment of Brain AVMs.

SUMMARY: Intravascular pressure measurements for several types of endovascular catheters were obtained in an in vitro model to validate the pressure readings obtained during the interventional procedures of brain AVM embolization. An experimental model was used where the beat rate, flow and pressures were as close as possible to the average human values of interest. It is shown that the corrections increase with the decreasing inner diameter of the catheter used and with increasing vascular pressure. We have also shown that there were no differences between measurements made with the catheter in the direction of flow or against it. An average pressure reading corrections for the various microcatheters to compensate the readings obtained during in vivo monitoring is presented. The haemodynamic assessment of 81 brain AVMs was performed using the endovascular measurement of arterial pressure in 389 feeding arteries during embolization. Mostly, the feeders' arterial median pressure was half the systemic arterial pressure but there was a wide variability of AV shunts in brain AVMs not only from one brain AVM to another but also within the same brain AVM. Measurement of arterial feeder pressure is an inexpensive, quick and accurate tool to evaluate the type of AV shunts within brain AVM.

[Angiographic evaluation and embolization of cervico-cranial tumors -- juvenile paraganglioma and angiofibroma of the nasopharynx]. / Avaliação angiográfica e embolização de tumores cérvico-cranianos--paragangliomas e angiofibromas juvenis da nasofaringe.

INTRODUCTION: The goal of pre-operative embolization is tumoral desvascularization, with decrease of intraoperative hemorrhage and shortening of operation time and, consequently, decrease operative morbility. The authors review their experience in angiographic evaluation and preoperative embolization of paragangliomas and juvenile nasopharyngeal angiofibroma (JNA). PATIENTS AND METHODS/RESULTS: There were reviewed the angiographic characteristics of 22 patients with paragangliomas, most of them jugular and/or tympanic, 10 of them embolized with PVA. There were angiographically evaluated 6 JNA, 5 of which were embolized with PVA. There weren't any neurological complications during the procedures, diagnostic angiography and embolization. In the cases submitted to endovascular treatment, there was a significative preoperative desvascularization rate, with subjective improving of intraoperative conditions in terms of blood loss. CONCLUSION: A detailed angiographic characterization of the tumor allows the evaluation of embolization risks, due to the presence of anastomoses or arterial feeding of important structures. Tumor preoperative embolization must be done in a restricted group of hypervascular tumors, in a multidisciplinary approach with the surgical team and must be a safe procedure, without carrying additional morbility to the surgery.

[Behçet's disease. Assessment with magnetic resonance of involvement of the central nervous system]. / Doença de Behçet. Avaliação por Ressonância Magnética do envolvimento do Sistema Nervoso Central.

UNLABELLED: Behçet's disease is a chronic multisystemic inflammatory disease that usually presents in the young adult. Central nervous lesions occur in 5 to 7% of patients and are the most severe manifestations of this disease. METHODS: We retrospectively reviewed the MR images of patients with neurological manifestations of Behçet's disease evaluated in the Neuroradiology Department of Garcia de Orta Hospital and the MRI center of Caselas, Portugal, between 1994 and January 2000. RESULTS: There were 8 cases of Neuro- Behçet. Patients' ages ranged from 24 to 46 years (mean 36.25). There were 4 males and 4 females (male/female ratio = 1:1). In 3 cases (37.5%) there was brainstem involvement, the basal ganglia and thalamus were affected in 2 cases (25%) and the internal capsule and corona radiata in 2 cases (25%). In 3 cases (37.5%) there was telencephalic white matter involvement and in 1 case (12.5%) the spinal cord was involved. CONCLUSION: The topography of the lesions, the absence of a defined arterial territory distribution and the partial or total regression of lesions over time help to distinguish BD from other vasculitic processes and inflammatory/demyelinating diseases.

[Magnetic resonance imaging of aqueductal flow in patients with normal hydrocephalus pressure]. / Estudo por ressonância magnética do fluxo aquedutal em doentes com hidrocefalia pressão normal.

The treatment of patients with the so-called Normal Pressure Hydrocephalus (NPH) consists of ventricular shunting, but only in some cases is there clinical improvement. The selection of patients for ventricular shunting is usually based on the response to the evacuating lumbar punctures of the cerebrospinal fluid (CSF), but new MRI techniques of flow measurement have been used successfully. In this study, a group of 58 patients, 28 of which with NPH, is presented. Flow quantification of the aqueductal CSF using the MR Phase Contrast technique was performed in all of them. The authors conclude that the method is sensitive and can be a valid criterium in the selection of patients for ventricular shunting.

[Cerebrovascular disease in pregnancy and puerperium]. / Doença cérebro-vascular na gravidez e no puerpério.

UNLABELLED: Cerebrovascular diseases are the main causes of neurological events occurring during pregnancy and puerperium. METHODS: We retrospectively reviewed the clinical records and imaging scans of females presenting with stroke during pregnancy or puerperium. We selected the cases with abnormal initial CT and/or MRI and a radiological follow-up until stabilization of the neurological condition. RESULTS: Eleven patients with ages ranging from 21-38 years were found. The hospital admission occurred between the second trimester of pregnancy and the first two weeks after delivery. In six cases there was a clinical setting of preeclampsia/eclampsia (PE/E): five with reversible encephalopathy syndromes (hypertensive-like encephalopathy) and one with a hematoma in a HELLP patient. Three other cases had a clinical setting of hypertension, not fulfilling the PE/E criteria, presented with hemorrhagic infarct in one case and lenticular hematoma in the other two. The other two cases were a subarachnoid hemorrhage in a patient with a middle cerebral aneurysm and a cortical venous infarct in a patient with lateral sinus thrombosis. CONCLUSION: Hypertension is the major underlying factor in peri-partum stroke. PE/E syndrome is the major leading cause of stroke in the peri-partum and maternal morbidity/mortality. MRI is very useful in evaluating this entity and, may have a positive impact on the management protocol.

[Fetal magnetic resonance]. / Ressonância Magnética fetal.

UNLABELLED: The increasing use of magnetic resonance imaging (MRI) in fetal evaluation is due to its excellent structural and morphological resolution. We report nine fetal MRI examinations and discuss some of the technical issues related to this technique. METHODS: We report nine fetal MRI done in the MRI Center in Caselas, Portugal, between January 1999 and March 2000. The fetal ages ranged from 24 and 33 weeks of gestation. RESULTS: The MRI diagnoses were: one normal case, two normal variants, two hydrocephalus due to intraventricular hemorrhage, one corpus callosum agenesis, one corpus callosum hypoplasia, one case with white matter encephaloclastic lesions and one case of torcular and superior sagittal sinus dilatation. In one case the MRI confirmed the ultrasonography (US) diagnosis, in two cases the MRI depicted the etiology of the pathologies found with US, in three cases there was a suspicion of pathology with US but the MRI was normal or had normal variants, and in three cases the MRI diagnoses were different from those made by US. CONCLUSIONS: MRI has the highest sensitivity for fetal imaging and should be used if the US is insufficient to establish the diagnosis.

Neuroradiological practices in Europe: Working ESNR Committee on Neuroradiological Practices in Neuroradiology. European Society of Neuroradiology.

In order to achieve an overview of neuroradiology in Europe a questionnaire was sent to all ESNR National Delegates. The answers received were submitted to a data-based analysis, leading to the conclusion that neuroradiology is an expanding discipline among neurological sciences.

Anatomoclinical Aspects of Dural Arteriovenous Shunts in Children. Review of 29 cases.

SUMMARY: We review 29 children (presenting between 1985-1996) with dural arteriovenous shunts. By analysing the anatomical features from axial and angiographic imaging and examining the clinical history and pathophysiological characteristics, we hypothesize that different diseases can be distinguished and divided into three groups: dural sinus malformation (DSM), infantile type of dural arteriovenous shunts (IDAVS) and adult type of dural arteriovenous shunts (ADAVS). It was helpful to classify these diseases when assessing the treatment options and long-term prognosis. Our group of 29 children comprised 19 DSM, 7 IDAVS, 3 ADAVS. A slight male preponderance was noted in the DSM group. The range of symptoms encountered included mild cardiac failure and coagulopathies, macrocrania, developmental delay, mental retardation, seizures and focal neurological deficits (in the neonates and early infancy age group) with or without haemorrhagic venous infarctions secondary to venous outlet restriction. We found all types of lesion in the neonatal age group, but in general the different types of lesion correspond to the paediatric subgroups with DSM occurring in the neonatal age group, IDAVS in infancy and ADAVS in children. DSMs are revealed in the first few months of live and the prognosis is good if the torcular is not involved. Two types can be seen: 1) DSM involving the posterior sinus with or without the confluens sinusum, with giant dural lakes and slow flow mural AV shunting. Spontaneous thrombosis may further restrict cerebral venous drainage and subsequently lead to intraparenchymatous haemorrhagic infarction. 2) DSM involving the jugular bulb with otherwise normal sinuses but associated with a high flow sigmoi'd sinus AVF. The prognosis is excellent with embolisation treament. IDAVS are high flow and low pressure. The sinuses are large and patent with no lakes. Clinical onset is seen in the first few years of life and the shunts are initially well tolerated. Progressive symptoms (symptoms of raised ICP and venous ischaemia) develop at a later age and initially respond to partial embolisation. The long term prognosis is poor with neurological deterioration in early adulthood. ADAVS present in all age groups and almost all of them are located in the cavernous venous plexus. Post embolisation outcome is excellent.

[A posttraumatic visual defect with late exacerbation associated with an aneurysm of the cervical internal carotid artery]. / Défice visual pós-traumático com agravamento tardio associado a aneurisma da artéria carótida interna cervical.

A posttraumatic visual deficit which worsened eleven weeks later, with sudden visual loss, is reported. The neuro-ophthalmologic examination was suggestive of central retina artery occlusion. The intra-arterial angiography revealed a traumatic pseudo-aneurysm of the ipsilateral high extracranial portion of the internal carotid artery. Based upon the clinical examination, the hypothesis of embolization has been considered the most probable mechanism, which is a rarely described etiopathogenesis. The clinical, pathogenic and diagnostic aspects of this situation are discussed. Finally, the authors describe the treatment, which consisted of the occlusion of the internal carotid artery with detachable latex balloons.

MRI in aqueduct compression and obstructive hydrocephalus due to an ecstatic basilar artery.

We describe a patient with an ecstatic basilar artery in whom MRI showed marked indentation of the floor of the third ventricle and backward displacement of the midbrain, probably causing aqueduct stenosis. It appeared likely that the associated hydrocephalus was due not only to any "water-hammer" effect, but also to occlusion of the aqueduct.

[Angiographic diagnosis of intracranial aneurysms: study of the experience of the neuroradiology service at the Egas Moniz Hospital]. / Diagnóstico angiográfico dos aneurismas intra-cranianos: estudo sobre a experiência do serviço de neurorradiologia do Hospital de Egas Moniz.

In this work, 139 intra-cranial aneurysms diagnosed at the Egas Moniz Hospital were studied, from 1980 to the first quarter of 1992. The nature of this type of lesions was discussed, and aneurysms were defined as an abnormal and segmental dilatation of an intracranial artery wall. A statistical study was performed, including 67 cases after selection, corresponding to 71 aneurysms. Of these, 39% originated from the anterior cerebral artery, 37% from the carotid siphon, 18% from the middle cerebral artery and 6% were found in the vertebro-basilar system. The observed topographic incidence of the symptomatic aneurysms was compared with neuropathology data. The results obtained with the hypothesis test for a proportion are suggestive of an increased incidence of symptoms for the aneurysms of the anterior cerebral artery, with a significance level alpha = 0.05.

[Development of the embolization technique for cerebral and spinal marrow arteriovenous malformations, and its clinical basis]. / Apontamento sobre a evolução da técnica de embolização das MAVs cerebrais e medulares, e seu fundamento clínico.

The authors revised 4 cases of large AVM's--3 cerebral and 1 medullary--illustrating the evolution of their technique of endovascular occlusion. These embolizations always preceding the surgery have their interest discussed in terms of the clinical grounds, the easiest access to the nidus and the possibilities of preventing some of the surgical risks.

[Contribution of angiography in the pre-operative evaluation of 24 jugulo-tympanic paragangliomas with otoneurologic manifestations]. / Contribuição da angiografia na avaliação pré-cirúrgica de 24 paragangliomas jugulotimpânicos com manifestações otoneurológicas.

The contribution of carotid and vertebral angiography for surgical planning, particularly for the infratemporal approach, in 24 jugulotympanic paragangliomas with otoneurological symptoms is discussed. These symptoms included peripheral facial palsy, sensorineural hypoacusis, labyrinthine and nervous syndrome of the jugular foramen. Angiography was essential for the diagnosis of these tumors and, above all, for the rigorous evaluation of intrapetrous and apical invasion of the carotid artery, and also of extra and intradural posterior fossa extensions. Presurgical embolization, a relevant step in treatment, was based on the criterious evaluation of the angiotopographic pattern of the tumoral hypervascularization.

Posterior fossa arteriovenous malformations. Angioarchitecture in relation to their hemorrhagic episodes.

Classically, posterior fossa arteriovenous malformations (PF-AVMs) have been considered as lesions with high tendency to bleed. However, careful analysis of clinical and autopsy data from the literature demonstrate that in fact the incidence of hemorrhage is similar in infratentorial and supratentorial locations. The clinical perception that most of the diagnosed PF-AVMs had bled does not mean that they have a high risk of hemorrhage. It suggests that bleeding is the dominant way of expression, since other symptoms are uncommon. Furthermore, angioarchitectural analysis is similar in supra- an infratentorial locations. The causes of hemorrhage are probably related to venous anatomic and hemodynamic changes or associated aneurysms as in other intracranial AVMs.