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R D Lobato

Publications and source records attributed to R D Lobato.

At least 55 records · Page 3Linked to original sources
PubMed2001

Ganglioglioma of the brainstem: report of three cases and review of the literature.

BACKGROUND: Brainstem gangliogliomas are rare low-grade tumors that usually have a long clinical history. However, they may cause sudden death. There are only 31 cases of brainstem ganglioglioma reported in the literature, and only one has been studied with magnetic resonance (MR). We present three new cases of brainstem ganglion cell tumor studied with computed tomography (CT) (3 cases) and MR (2 cases) and discuss the clinical presentation, diagnostic imaging and treatment of these tumors. CASE DESCRIPTION: Age at presentation ranged from 19 to 59 years old. Two patients were female and 1 male. Duration of symptoms before diagnosis ranged from 1 year to nearly 14 years. Presenting complaints included syncope spells, cranial nerve deficits, headache, and gait instability. Imaging studies revealed well-circumscribed lesions involving the brainstem; the lesion was cystic in one case and calcified in one. They were iso- or hyperdense on CT scan, isodense on T1-weighted and hyperdense on T2-weighted MRI and frequently showed contrast enhancement. All tumors were operated through a posterior fossa craniectomy. Using microsurgical techniques only partial resection could be achieved, as there was no sharp delineation from the surrounding tissue in any case. Two of our patients had increased neurological deficits after surgery. Radiotherapy was not given. Follow-up of tumoral remnants has not shown clear tumor growth after 1, 3.5, and 10 years. CONCLUSIONS: Imaging characteristics of brainstem gangliogliomas do not seem to differ from those in other locations and are not specific. Radical surgery is rarely if ever possible, nor is it advisable because of the risk of functional deterioration. However, because of their benign histology, partial resection seems to carry a similar prognosis as tumors in other locations that are amenable to complete resection.

Adult↗
PubMed2001

[Subarachnoid hemorrhage secondary to dissecting aneurysms of the vertebral artery. Description of 2 cases and review of the literature].

UNLABELLED: OBJECTIVES AND INTRODUCTION: The pathogenesis and natural history of intracranial vertebral artery dissection remain uncertain up to now due in part to its relative rarity. In this article we review the state of the art of this process and remark the good outcome obtained with embolization using Guglielmi detachable coiling (GDC). METHODS: Two cases with subarachnoid hemorrhage secondary to rupture of a vertebral dissection aneurysms are described. The first patient initially suffered brain stem infarction, followed by a subarachnoid hemorrhage a year later. The second patient who had a severe subarachnoid hemorrhage with two early rebleedings was successfully treated with embolization using GDC. CONCLUSIONS: Subarachnoid hemorrhage due to rupture of vertebral dissecting aneurysm is a relatively unknown disease with some important aspects that should be known. The high incidence of early rebleeding (up to 60%), makes early diagnosis and treatment important goals. Classically the preferred treatment has been proximal vertebral artery occlusion. However, the recent introduction of embolization with GDC has made possible the occlusion of the dissection with very good final outcome.

Aged↗
PubMed2001

Parosteal osteosarcoma of the skull.

Parosteal osteosarcoma of the skull is a distinct surface bone tumor, with a better prognosis than conventional osteosarcoma. The most common location is on the surface of the distal femur which accounts for 46-66% of the cases. The presentation in the skull is uncommon and there are few cases reported in the literature. We describe the case of a man who developed a parosteal osteosarcoma arising from the occipital bone with extension to the parietal bone. The patient was operated and had a complete tumor resection.

Cerebral Angiography↗
PubMed2001

[Research training in the programs of neurosurgery residency. Analysis of the situation in other developed countries and proposals to implementing the current program in Spain].

Research performed by neurosurgeons has been always linked to the progress of our specialty, and research training is included in the Neurosurgery Residency Programs in developed countries. Since the methodology of research related to the basic knowledge of the nervous system function is becoming increasingly complex, it could be proposed that neurosurgeons can not longer contribute to productive research in neurosciences, and this idea might be easily accepted in certain countries such as Spain, where research training is not contemplated in the Residency Program of Neurosurgery. However, all neurosurgeons academic or not, should exhibit a critical and inquiring mentality which enables them to evaluate scientific information and communicate their own clinical experience to the neurosurgical community. Such a critical capacity can not be acquired by a resident trained only in the art of clinical diagnosis and the surgical technique. The new medical practice is based on both basic and clinical-epidemiological research, and the new residents must be immersed into a motivating and inquisitive environment in which the scientific method is continuously applied to the clinical practice. In this paper I consider research training in Neurosurgery in developed countries with the aim of identifying a strategy for introducing a period devoted to research in the Spanish Residency Program. Thus, the methodologies, objectives, contents, duration and the moment for receiving research training in other countries are analysed and some alternatives for solving the problem in our country are pointed out.

Developed Countries↗
PubMed2001

[Meningioma of the olfactory groove: review of a series of 27 cases].

OBJECTIVE: To describe our experience with olfactory groove meningiomas, analysing their clinical and radiological form of presentation and their surgical treatment. METHODS: The clinical records of 27 patients diagnosed of olfactory groove meningioma, extracted from the series of meningiomas operated on in our department since 1973, were retrospectively reviewed. Demographical data, the clinical presentation and duration of the symptoms before diagnosis were collected. Several radiological characteristics were also reviewed such as the tumour size, associated brain edema, type of contrast enhancement, presence of endostosis and invasion of the cranial base. The surgical resection grade, the histological type and the presence of recurrences in the follow-up were also analysed. RESULTS: The average age at presentation was 59 years. Average duration of symptoms prior to diagnosis was 39 months. The most frequent symptom at presentation was higher function impairment (52%), The average maximum tumoral diameter was 6.2 cm. 61% of the patients presented moderate or severe brain edema, which was quite frequently bilateral (74%). Radiological endostosis was present in 37% of the cases, but there were no signs of bone invasion in any case. The approach used was the basal frontal, uni or bilateral. In all cases the grade of resection was Simpson II. The majority of the cases presented a typical histology. Over 80% of the cases presented a good recovery at discharge. None of the patients presented with a tumoral recurrence after an average radiological follow-up of 74 months. CONCLUSIONS: The olfactory groove is an infrequent location for intracranial meningiomas, accounting for only 4.5% of all meningiomas in our experience. These tumours reach a big size due to the delay in diagnosis. Drilling of the cranial base does not seem necessary for preventing tumoral recurrence.

Adult↗
PubMed2001

Basal ganglia hematomas in severely head injured patients: clinicoradiological analysis of 37 cases.

OBJECT: The authors analyzed the clinicoradiological presentation of traumatic basal ganglia hematomas (TBGHs) in severely head injured (SHI) patients. METHODS: The records of 37 patients (28 male and nine female patients with a mean age of 28 years) in whom computerized tomography (CT) scans revealed TBGHs 2 ml or more in volume were retrospectively reviewed. These cases represented 2.4% of the total series of 1526 SHI patients admitted to the authors' institution between 1979 and 1998. Thirty-five patients (94%) were involved in traffic accidents and only two exhibited a period of lucidity. Associated extracranial injuries were seen in 21 patients (57%) and coagulation disorders in 32 (86%). Skull fracture was present in 10 (43%) of the 23 patients in whom skull x-ray films were obtained. Computerized tomography findings indicated diffuse axonal injury in 27 patients (73%), intraventricular hemorrhage in 22 patients (59%), and subarachnoid hemorrhage in 16 patients (43%). In all but two patients, the TBGHs were visible on the initial CT scan, and in 28 cases (76%) these hematomas were contralateral to the side of impact. Hematoma enlargement over the first few posttraumatic days was noted in 65% of the patients in whom control CT scans had been obtained (22 of 34 patients). Four patients (11%) underwent surgery to remove their TBGHs. Final outcomes were poor: 22 patients (59%) died, two (5%) became vegetative, seven (19%) experienced severe disabilities, and only six patients (16%) made a favorable recovery. CONCLUSIONS: Traumatic basal ganglia hematomas are dynamic lesions that tend to enlarge during the acute posttraumatic period. The overall prognosis in this series was poor. Patients in whom the volume of the hematoma was larger than 25 ml and those in whom hematoma volume enlargement or raised intracranial pressure occurred had the worst outcomes, perhaps indicating the need for a more aggressive surgical treatment.

Adolescent↗
PubMed2001

[Tentorial meningiomas. A study of 14 surgically verified cases].

OBJECTIVE: Complete surgical resection is considered to be the elective treatment for tentorial meningiomas. The objective of this work is to describe the clinical and radiological characteristics of these tumours, the best surgical approach, complications related to surgery and long term outcome of patients harbouring a meningioma at this location. MATERIALS AND METHODS: A series of 14 patients with tentorial meningiomas consecutively operated at our department between 1977 and 1999 is analyzed. Twelve patients were studied with CT and the last 8 with MR. Arteriography or angio-MR were performed in some patients when dural sinuses involvement was suspected. Tumoral resection was evaluated by means of Simpson Scale and final outcome according to the Glasgow Outcome Scale (GOS). RESULTS: Nine patients were female and 5 male. Mean age was 64 years (41-82). The average duration of presenting symptoms was 17 months. Headache was the most frequent presenting symptom. The tumour was implanted at the tentorial free edge in 4 cases, at the lateral region in 9 and at the falcotentorial region in 1 case. Complete surgical resection (Simpson I-II) was achieved in 10 cases. Final outcome was good recovery in 9 cases, moderate disability in 1, severe disability in 2 and two patients died. CONCLUSIONS: Surgery is the elective treatment for tentorial meningiomas. In most cases, complete surgical resection should be the objective. Subtotal resection may be considered when the tumour invades a patent dural sinus or the cavernous sinus or when the tumour is closely adherent to the brain stem. In these cases a close follow up is needed and reoperation or radiosurgical treatment may be contemplated if residual tumour growth occurs.

Adult↗
PubMed2000

Suprasellar chordoid glioma.

Brat et al. (J Neuropathol Exp Neurol 57:288-290, 1998) reported eight cases of a new clinico-pathological entity, which occurs mainly in the third ventricle of middle-aged females, which they described as chordoid glioma of the third ventricle. We report a new case of a 41-year-old woman with a suprasellar chordoid glioma with histological, immunohistochemical and ultrastructural studies. We discuss the differential diagnosis between chordoma, chordoid meningioma, germinoma and pituitary adenoma. Histologically, the tumour showed cords and lobules of isomorphic epithelioid cells in a vacuolated matrix with prominent multifocal lymphoplasmacytic infiltrates in which some histiocytes and isolated Touton-type giant cells were seen; cells were immunoreactive for glial fibrillary acidic protein but negative for epithelial membrane antigen. Ultrastructural examination revealed abundant intermediate filament but no desmosomes, microvilli nor cilia were seen.

Adult↗
PubMed2000

Age and outcome after severe head injury.

The authors analyzed the relationship between patient age and the final outcome in a series of 810 patients aged 14 years or older who were consecutively admitted between 1987 and 1996 after suffering a severe closed head injury. The most relevant clinico-radiological variables were prospectively collected in a Data Bank. Stratified and logistic regression analyses were performed in order to assess the influence of age on adverse outcome and the interaction between patient age and other prognostic indicators. Our results reaffirm that the adverse outcome rate increases steadily with age in severe head injured patients and that age effect on outcome is independent of other prognostic variables. The odds of having an adverse outcome increases significantly over 35 years of age being 10 times higher in patients older than 65 years as compared to those aged 15-25 years (reference age group). The adverse influence of an advanced age on the final outcome has not yet been satisfactorily explained but an older brain may have an impaired ability to recover after a pathological insult as compared to a younger one.

Accidents, Traffic↗
PubMed2000

Spinal cord ependymoma presenting with acute paraplegia due to tumoral bleeding.

Acute paraplegia is a rare presentation for a spinal cord ependymoma Among spinal cord tumors ependymomas are most commonly associated with subarachnoid hemorrhage and there is evidence that some have had intratumoral hemorrhage, but most of these bleedings pass without symptoms. In this report, a case of spinal cord ependymoma debutting with acute neurological deterioration due to tumoral bleeding is presented. We discuss the clinical and neuroradiological findings and review the literature related to this unusual presentation.

Adult↗
PubMed1999

Surgical findings in idiopathic trigeminal neuropathy mimicking a trigeminal neurinoma.

Idiopathic trigeminal neuropathy is a benign disorder where the main clinical feature is facial numbness limited to the territory of one or more divisions of the trigeminal nerve, persisting for a few weeks to several years and in which no underlying disease can be identified. The case of a 37-year-old man with a brief history of sensory and motor trigeminal symptoms who showed magnetic resonance imaging (MRI) findings consistent with a small trigeminal neurinoma is reported. The patient was operated on but no tumour could be found during surgery and a biopsy was taken from the portio major. Pathological diagnosis was chronic non granulomatous inflammatory reaction with areas of coagulation necrosis. Control MRI showed complete resolution of the trigeminal abnormalities. It is concluded that in patients with MRI findings suggestive of a small trigeminal schwannoma, benign idiopathic trigeminal neuropathy should also be considered in the differential diagnosis. A conservative approach with sequential MRI studies may avoid an unnecessary surgical exploration.

Adult↗
PubMed1999

Risk factors predicting recurrence in patients operated on for intracranial meningioma. A multivariate analysis.

The authors undertook a follow-up study of 286 patients who underwent surgical treatment for intracranial meningioma between 1973 and 1994, in order to analyse clinical, radiological, topographic, histopathological and therapeutic factors significantly influencing tumour recurrence. All patients were followed by using either computed tomography (CT) or magnetic resonance from 3 months to 17 years since first surgery (mean follow-up: 4.1 years). Forty-four (15.4%) recurrences were detected during this time period. Overall recurrence rates were 14%, 37% and 61% at 5, 10 and 15 years, respectively. Factors significantly associated with tumour relapse in bivariate analysis were: tumour location at petroclival and parasagittal (middle third) regions, incomplete surgical resection (assessed by Simpson's classification), atypical and malignant histological types (WHO classification), presence of nucleolar prominence, presence of more than 2 mitosis per 10 high-power fields, and heterogeneous tumour contrast enhancement on the CT scan. The multivariate analysis using the Cox's proportional hazards model identified the following risk factors for recurrence: incomplete surgical resection (Relative risk: 2.2; 95% Confidence interval: 1.33-3.64), non conventional histological type (RR: 2.13; 95%CI: 1-4.53), heterogeneous contrast enhancement on the CT scan (RR: 2.25; 95%CI: 1.1-4.72) and presence of more than 2 mitosis per 10 high-power fields (RR: 2.28; 95%CI: 0.99-5.27). Patients without any of these features showed low recurrence rates (4% and 18% at 5 and 10 years), and thus, they need less clinical and radiological controls through the follow-up than patients with some of these risk factors.

Adolescent↗
PubMed1999

Cerebral aneurysm rupture after r-TPA thrombolysis for acute myocardial infarction.

BACKGROUND: Intracranial hemorrhage is the most dreaded risk of thrombolytic therapy for acute myocardial infarction because of the high mortality and disability rates associated with this complication. Brain structural lesions may predispose a patient to bleeding. To date, aneurysm rupture has not been described as a complication of such therapy. CASE DESCRIPTION: A 66-year-old hypertensive woman was admitted because of chest pain. Myocardial infarction was diagnosed and fibrinolytic therapy with recombinant tissue plasminogen activator (r-TPA) was initiated. Eight hours after admission she became unconscious. Brain computed tomography scan showed subarachnoid hemorrhage, and a cerebral arteriography showed an anterior communicating artery aneurysm. Because of her poor clinical condition treatment was postponed. Death occurred 7 days later because of multiorgan failure. CONCLUSIONS: Cerebral aneurysms should be considered as a possible contributing factor to intracranial bleeding after thrombolytic therapy.

Aged↗
PubMed1997

Idiopathic normal pressure hydrocephalus: analysis of factors related to cerebrospinal fluid dynamics determining functional prognosis.

This investigation has been undertaken to analyze the findings with both the cerebrospinal fluid (CSF) pressure (Pcsf) and CSF pulse pressure (PP) in order to predict the outcome of patients with the syndrome of idiopathic normal pressure hydrocephalus (NPH). Accordingly, a prospective clinical study was planned in which two groups of patients with NPH, having analogous prevalence of several matched clinical and radiological parameters, were separated on the basis of their positive or negative response to shunting. Both the resting Pcsf and CSF PP profiles were compared in these two groups, and between them and normal controls. CSF PP amplitude and CSF PP latency correlated directly in conditions associated with either normal or high compliance (controls and patients with Alzheimer-like disorders), whereas this correlation was inverse in states of low compliance (NPH). On the other hand, shunt-responders showed a resting Pcsf significantly higher than both non-responders and controls. The following conclusions were obtained: 1) CSF PP is a high-amplitude and relative low-latency wave in NPH when compared with controls: 2) CSF PP amplitude and latency correlate directly in normal subjects and in those with primary cerebral atrophy; 3) a non-reversible stage of NPH could be conceived in contradistinction to the reversible one, in both of which an inverse correlation between the amplitude and the latency takes place, the main difference between them being the resting Pcsf, which is significantly lower in the former than in the latter, depending on the degree of atrophic changes developed.

Adult↗