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Biomedical subjects

J J Rivas

Publications and source records attributed to J J Rivas.

53 records · Page 3Linked to original sources
PubMed1986

Symptomatic subependymoma: report of four new cases studied with computed tomography and review of the literature.

The authors describe four cases of subependymoma studied with computed tomography (CT) and review 18 previously reported cases in an attempt to define the most characteristic CT presentation of this rare, benign tumor. Subependymoma usually appears as an isodense, or even hypodense, intraventricular tumor on plain CT scan and shows minimal or no enhancement in postcontrast studies. Differential diagnosis between subependymoma and the more malignant true ependymoma is difficult, particularly when the tumor occurs in the posterior fossa. Recognition of subependymoma should prompt the surgeon to attempt radical tumor removal because it can be achieved without sacrificing contiguous tissue and carries a good prognosis.

Adolescent↗
PubMed1986

Normal computerized tomography scans in severe head injury. Prognostic and clinical management implications.

The authors analyze the clinical course of 46 severely head-injured patients who had completely normal computerized tomography (CT) scans through the immediate posttraumatic period (1 to 7 days after trauma). These patients represent 10.2% of a consecutive series of 448 cases of severe head injuries and two-thirds of the cases showing a normal CT scan on admission (the other one-third of the cases developed new pathology). The usual course in these 46 patients after the initial coma was toward progressive neurological improvement, and 35 patients (76%) achieved a functional level of survival. Nine patients (19.5%) remained comatose for several weeks and developed severe disability. There were two fatalities due to medical complications. The final outcome was more closely related to the duration of coma (the longer the duration the worse the result) than to the initial Glasgow Coma Scale (GCS) score. In fact, 26% of the patients in the lower GCS score ranges (3 to 4 points) made a good recovery and 46% developed moderate disability only. These findings indicate that the grim prognostic significance of deep posttraumatic coma is tempered in the presence of a normal scan. However, the absence of CT abnormalities in severely head-injured patients cannot be equated with a good prognosis because in one-fifth of the cases serious permanent disability develops. Sustained elevation of the intracranial pressure (ICP) was not seen in these patients, indicating that ICP monitoring may be omitted in cases with a normal scan. However, since one-third of the patients with a normal admission scan developed new pathology within the first few days of injury, a strategy for control scanning is recommended. Control CT scans performed more than 6 months after injury showed a significantly higher incidence of brain atrophy in patients developing permanent disability than in those who made a good recovery.

Adult↗
PubMed1985

CT-assisted stereotaxic aspiration of colloid cysts of the third ventricle.

A technique is reported for the stereotaxic evacuation of colloid cysts of the third ventricle using a stereotaxic system adapted for computerized tomography (CT) scanning. This is an accurate, simple, and reproducible method that avoids the risks of direct approaches. Successful intracystic aspiration resulting in the cure of the patient may be difficult when the viscosity of the cyst contents is high. Thus, the authors use a large cannula (1.8 mm in inner diameter) to evacuate cysts that appear hyperdense on CT scans; these seem to contain a thicker colloid material than hypodense or isodense cysts.

Aged↗
PubMed1984

Spinal metastatic disease: analysis of factors determining functional prognosis and the choice of treatment.

The authors surveyed 31 surgical and radiotherapy series comprising over 2300 patients with spinal metastases to determine the influence of factors such as tumor biology and topography, pretreatment neurological status, the presence of a myelographic block, the progression rate of symptoms, and the general medical condition of the patient on both the functional prognosis and the choice of treatment. Both life expectancy and the functional results after therapy are mainly dependent on tumor biology, which in turn determines radiosensitivity. The remaining factors seem to have only complementary predictive power. Because radiotherapy has been found to be as effective as operation plus radiotherapy in the management of the majority of patients with spinal metastases, it is very important to improve the selection of surgical candidates (less than 42% of the total cases) to prevent unnecessary surgery-related morbidity and mortality. Factors considered important in the selection of therapy are the location of the tumor within the spinal canal, the neurological status at the time of treatment, and the systemic condition of the patient.

Combined Modality Therapy↗
PubMed1983

Intraventricular morphine for control of pain in terminal cancer patients.

Satisfactory control of intractable pain has been achieved in 17 terminal cancer patients by injecting small doses of morphine into the lateral cerebral ventricle via an Ommaya reservoir. Pain relief together with a favorable behavioral response was obtained without interference with other sensory modalities, noticeable physical changes, or side effects annoying or severe enough for the patient to discontinue therapy. Eleven patients developed tolerance, but this phenomenon does not require withdrawal of treatment. Chronic intraventricular morphine administration can be safely performed on an outpatient basis, and results in control of midline, bilateral, and diffuse pain associated with orofacial and disseminated cancer. However, this experience is preliminary and further clinical trials are needed to determine the place of this method of therapy in the management of chronic pain.

Aged↗
PubMed1983

Outcome from severe head injury related to the type of intracranial lesion. A computerized tomography study.

The influence of the type of intracranial lesion on the final outcome in a consecutive series of 277 severely head-injured patients was analyzed. Patients were studied with computerized tomography (CT) and underwent continuous measurement of intracranial pressure. They received identical treatment according to a standardized protocol. Outcome of patients with either epidural hematoma (38 cases), subdural hematoma (56 cases), brain contusion (87 cases), or diffuse brain damage (96 cases) was rather heterogeneous, and serial CT scanning allowed the authors to outline eight consistent anatomical patterns in the whole series which have stronger prognostic significance than the four major lesion categories mentioned above. Patients with pure extracerebral hematoma (19 cases), single brain contusion (45 cases), general brain swelling (41 cases), and normal CT scans (28 cases) had a significantly better outcome than patients developing acute hemispheric swelling after operation for a large extracerebral hematoma (27 cases), patients with multiple brain contusion, either unilateral or bilateral (74 cases), and patients with diffuse axonal injury (43 cases). These anatomical patterns are interesting because, in addition to having clinical and physiopathological significance, they provide useful prognostic information and facilitate improved therapeutic decision-making in severely head-injured patients.

Adolescent↗
PubMed1982

Intermittent exophthalmos studied with computerized tomography. Report of two cases.

Two cases of intermittent exophthalmos are reported. In both instances, cerebral angiography and orbital venography failed to outline the lesion, which was clearly demonstrated with the aid of computerized tomography. An orbital varix was seen to be the cause of proptosis in one surgically verified case, whereas in the other this same diagnosis was suspected on the basis of the clinicoradiological findings. The etiology, clinical manifestations, and management of orbital varix are briefly discussed.

Adult↗
PubMed1981

Observations on 82 patients with extradural hematoma. Comparison of results before and after the advent of computerized tomography.

A consecutive, unselected series of 82 patients with epidural hematoma treated between 1973 and 1980 is presented. Forty-one patients were managed before the advent of computerized tomography (CT) and the other 41 after this neuroradiological method was available. Mortality and disability rates which were 29.2% and 31.7% during the pre-CT period decreased to 12.1% and 19.5%, respectively, with the aid of CT scanning. This technique allowed a more rapid and accurate diagnosis of the hematomas than angiography, and defined better the presence and the evolutional changes of the associated cerebral lesions. As a consequence, surgery has been more effectively planned and executed during the CT era.

Adolescent↗
PubMed1981

Hydrocephalus in cerebral cysticercosis. Pathogenic and therapeutic considerations.

The cases of 11 patients with hydrocephalus secondary to cerebral cysticercosis are analyzed. Most of the patients had suffered from epilepsy before they developed hydrocephalic symptoms, and computerized tomography showed that infestation of the parenchyma coexisted with ventricular or cisternal colonization. In four cases, the parasitic vesicles compromised cerebrospinal fluid (CSF) flow in the ventricular system, resulting in internal hydrocephalus. Communicating hydrocephalus, caused by the presence of Cysticercus larvae in the basal cisterns (Cysticercus racemosus), or by the occurrence of a chronic basal meningitis, or both, developed in seven more patients. Changes in CSF pressure were related to the number and location of the cysts and to the leptomeningeal inflammatory reactions evoked by them. The majority of patients presented with a chronic and relatively normotensive hydrocephalus. All patients except one had identifiable ventricular or cisternal Cysticercus larvae; these patients were treated with open removal of the cysts, and did well. However, most of them had impairment of CSF flow through the basal cisterns and required permanent CSF shunting. Communicating hydrocephalus due to leptomeningeal scarring was also successfully managed with extracranial shunting. Epilepsy was controlled with anticonvulsant therapy. Although good lasting results may be obtained with aggressive treatment of neurocysticercosis, patients are liable to relapse because surgery is only palliative in most instances.

Adult↗
PubMed1978

Primary calvarial hemangioma: angiographic study.

Two cases of primary hemangioma of the calvarium are reported. Preoperative diagnosis was easily made in both cases because of the typical roentgenographic presentation. Clinical and radiological aspects of this vascular benign tumor of the skull are discussed.

Cerebral Angiography↗
PubMedDate not supplied

[Idiopathic spinal cord herniation. Presentation of a new case and review of the literature].

INTRODUCTION: Idiopathic herniation of the spinal cord is a rarely diagnosed condition. It is important since this cause of paraparesis is potentially curable if diagnosis is made early. Our aim is to report a new case, review the relevant literature, describe the radiological findings and consider the etiopathogenic findings. CLINICAL CASE: We report the case of a 56 year old man with increasing difficulty in walking attributed to stenosis of the lumbar spinal canal, which did not improve after laminectomy. On examination he had sensory and motor deficits compatible with the Brown-Séquard syndrome. Dorsal MR showed ventral displacement of the thoracic spinal cord with disappearance of the anterior subarachnoid space together with a posterior arachnoid cyst at the same site. A further operation was done at the same place and the cyst removed. However, it was impossible to free the spinal cord since there was severe spinal arachnoiditis. The patient made little improvement. CONCLUSIONS: Herniation of the spinal cord is a rarely diagnosed condition. After careful study of the literature it seems that all patients present in a similar manner. Clinically there is a disorder of gait compatible with the Brown-Séquard syndrome. On MR there is sudden ventral displacement of the thoracic spinal cord, associated in some cases with an arachnoid cyst. When surgery is effective there is great improvement, so this diagnosis should be remembered in all cases of progressive paraparesis.

Aged↗
PubMedDate not supplied

[Bilateral thalamic gliomas: report of a case with cognitive impairment].

INTRODUCTION: Bilateral thalamic tumours are very rare and have been recently identified as a subgroup of thalamic neoplasms due to their characteristic clinical presentation, with behavioural and memory disorders and without sensory or motor changes. We describe a patient who presented with mood and behaviour changes due to a bilateral thalamic glioma, discuss the literature related to these rare neoplasms and review the anatomical bases of their particular clinical presentation. CASE REPORT: A 67-year-old woman consulted because of behavioural changes and frequent forgetfulness. Neurological examination was normal except from a deficit in the retention of words and numbers. MR images revealed bilateral thalamic swelling by a isointense in T1, hyperintense in T2 and protonic density mass that did not enhance. The tumour was diagnosed as an astrocytoma by stereotactic biopsy. She continued to deteriorate and a year after diagnosis she was bedridden and with a severe dementia. CONCLUSION: Bithalamic tumors, as other lesions that affect the thalamus bilaterally, characteristically present with mood and behaviour changes and memory impairment.

Aged↗
PubMedDate not supplied

Actinomycotic brain abscess.

Actinomycosis is a chronic, suppurative and granulomatous bacterial infection, which tends to form abscesses. Involvement of the central nervous system (CNS) is rare. We describe the clinical and neuroradiological findings of four patients (3 men and one female) diagnosed of actinomycotic brain abscesses. Risk factors were dental pathology, intrauterine device use, alcohol abuse and Rendu-Osler-Weber disease. Clinical manifestations were those of a space-occupying lesion. CT scan findings were varied and little specific: hemispheric or periventricular location, pyocephalus, rim-enhancing and edema. MRI was superior in disclosing pyocephalus. Diagnosis was performed by microbiological and pathological findings. Despite surgery and antibiotics, two of the patients died. In conclusion, the infection of the CNS by Actinomyces is potentially fatal and should be considered in those patients with cerebral abscess.

Abscess↗