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R D Lobato

Publications and source records attributed to R D Lobato.

At least 91 records · Page 5Linked to original sources
PubMed1988

Posttraumatic cerebral hemispheric swelling. Analysis of 55 cases studied with computerized tomography.

The authors have analyzed the clinical course and intracranial pressure (ICP) changes in 55 severely head-injured patients presenting with bulk enlargement of one cerebral hemisphere within a few hours after trauma. These patients represent 10.5% of a series of 520 patients with severe head injury studied with computerized tomography (CT). Cerebral hemispheric swelling has the highest mortality rate and the shortest survival period after trauma in all series of severe head injury. In this series, it was associated with an ipsilateral subdural hematoma of variable size in 47 patients (85%) or with a large epidural hematoma in five patients (9%); in three patients (5.4%) it occurred as an isolated lesion. Evacuation of an associated extracerebral hematoma, which was performed within 4 hours after injury in only 20% of cases, scarcely changed the patients' preoperative neurological status. The high incidence of arterial hypotension and/or hypoxemia at admission (47% of cases) and the severity of the clinical presentation (82% of patients scored 5 points or less on the Glasgow Coma Scale, 74% had unilateral or bilateral mydriasis, and 80% had an initial ICP above normal) correlated with a very poor final outcome (87% mortality). Only one of the 11 patients with normal initial ICP continued to have normal pressure throughout the course. High-dose thiopental failed to control severe intracranial hypertension in 24 patients (51%) who had a fulminant, malignant course. A transient decrease in ICP elevation was achieved in 15 patients (31.4%) and definitive control in eight patients (17%), among whom were the seven survivors in this series. In the authors' experience, once ICP is controlled, barbiturate administration should not be discontinued until a control CT scan shows complete disappearance of the mass effect.

Adolescent↗
PubMed1988

Clinical, radiological, and pathological spectrum of angiographically occult intracranial vascular malformations. Analysis of 21 cases and review of the literature.

The clinical, radiological, and histopathological features of 21 cases of angiographically occult intracranial vascular malformations (AOIVM's) are analyzed, and a review of 241 additional appropriately documented, histologically verified cases collected from the literature is presented. In all, there were 115 (43.8%) arteriovenous malformations, 82 (31.2%) cavernous angiomas, 26 (9.9%) venous angiomas, 10 (3.8%) cases of capillary telangiectasis, and 29 (11%) mixed or unclassified angiomas. The result of the analysis shows that there are no essential differences in the patterns of clinical presentation, the computerized tomography (CT) appearance, or the surgical prognosis among these pathological types of vascular malformations. Certain histological features common to all AOIVM's (such as the small caliber, the more or less complete thrombosis of the malformed vessels, and the changes induced in the surrounding brain tissue by repeated microhemorrhages) seem to determine the biological behavior of the anomaly rather than the predominant type of vessel involved. Thus, subdivision of AOIVM's into the four classical pathological types has little practical value. Most AOIVM's are visualized by the CT scan and show a rather typical appearance. Surgical removal, which prevents rebleeding and ameliorates or suppresses seizure activity, is usually easy to perform and represents the treatment of choice for patients with clinically symptomatic AOIVM's.

Adolescent↗
PubMed1987

Post-traumatic diffuse brain swelling: isolated or associated with cerebral axonal injury. Clinical course and intracranial pressure in 18 children.

Eighteen children with severe head injuries and diffuse brain swelling were studied. They were separated into two groups based on the computed tomography (CT) findings. Seven patients had small ventricles in the normal location and small or absent cisterns. Eleven had these signs plus small deep-seated intraparenchymal hemorrhagic foci and/or intraventricular hemorrhage. Patients in the first group were in relatively good neurological condition; their intracranial pressure was easily controlled and all had a favourable outcome. On contrast, children in the second group had a more severe clinical presentation, frequently had uncontrollable intracranial hypertension, and more than 50% died.

Axons↗
PubMed1987

Applications of CT-adapted stereotaxis for the diagnosis and treatment of intracranial lesions.

Two hundred twenty five patients with intracranial lesions underwent diagnostic and therapeutic stereotactic surgery during the period 1978-1985. In the first 98 cases target coordinates were determined by transferring the information from the CT images to the standard stereotactic films. In the remainder, a simple, CT adapted stereotactic system has been used. Operations were as a rule performed under local anaesthesia. Positive histological diagnosis using paraffin embedding was achieved in 96% of the patients (biopsy success rate). Therapeutic procedures included abscess and cyst aspiration, cyst shunting, interstitial (Ir 192) or intracavitary (Y 90) irradiation and ventriculocisternostomy. Stereotactic surgery implied a refinement of the eventual therapeutic management in 90% of the cases. Transient neurological deficit occurred in 5.7% of the patients and there were three deaths (mortality rate 1.3%). Infection or other complications were not seen. The rationale and indications for non-functional stereotaxis are discussed.

Adolescent↗
PubMed1987

Intrathecal therapy: rationale, technique, clinical results.

In 35 patients a subcutaneously implanted injection port/reservoir was used to provide intrathecal morphine to relieve pain due to cancer. The reservoir offers an alternative to rather expensive devices. It can be used for repeated injections or for infusion. It is easy to locate and facilitates ambulatory treatment. The injections were carried out by members of the patient's family after they had been taught how to do it. Initially, doses of 0.25-0.5 mg of morphine resulted in pain relief for 14 to 24 hours. After 5 weeks of treatment morphine requirements increased to 0.75-2 mg. Side-effects were minimal, and three delayed CSF fistula, two of them confirmed by isotope tracking with Tc99m, closed spontaneously.

Adolescent↗
PubMed1987

Intraventricular morphine for intractable cancer pain: rationale, methods, clinical results.

The experience with the administration of intraventricular morphine for the control of malignant pain in 197 patients is analyzed. Small doses of morphine injected via a ventricular reservoir provided satisfactory control of otherwise intractable pain in terminal cancer-patients. Complete analgesia together with a favourable behavioral response was obtained without noticeable neurological changes or side-effects annoying or severe enough for the patients to discontinue therapy. Tolerance was much less marked than with parenteral opiates. Chronic intraventricular therapy can be safely performed on an outpatient basis by injecting the opiate once or twice a day. The method may be improved by using refillable continuous-infusion devices and new drugs, able to retain the analgesic effects of morphine while eliminating the unwanted ones.

Adolescent↗
PubMed1986

Post-traumatic diffuse axonal brain injury. Analysis of 78 patients studied with computed tomography.

A group of 78 severe head injury patients showing computerized tomography (CT) findings of the so-called "diffuse axonal injury" is analyzed. These patients represent 20% of the authors' series of severe head injury. Twenty-three patients showed small intraparenchymal haemorrhages in the CT scan study, 15 intraventricular haemorrhage and 40 patients had both intraparenchymal and intraventricular haemorrhages. Signs of brainstem haemorrhagic contusion were seen in 29 (38%) patients. Generalized brain swelling superimposed on the above findings was present in 75% of the cases. Raised intracranial pressure, which was found in 50% of the patients, correlated with the presence of ventriculocisternal collapse in the CT scan and an unfavourable outcome. Only 4 patients in this series made a good recovery, 13 developed a moderate disability, 11 a severe disability, 12 became vegetative and 38 (49%) died. The prognosis with this post-traumatic lesion is the worst in the authors' severe head injury series after excluding cases with subdural haematoma.

Adolescent↗
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↗
PubMed1985

[Effect of experimental subarachnoid hemorrhage on calcium incorporation and adrenergic innervation of the cerebral arteries of the cat].

The effect of experimental subarachnoid hemorrhage (SAH) on the adrenergic innervation and on the 45Ca2+ uptake of cat cerebral arteries was analyzed. Intracisternal injections of autologous blood reduced the noradrenaline content of perivascular nerve endings and 3H-noradrenaline uptake. These values returned to normal levels in a period of two weeks after SAH. The activity of dopamine-beta-hydroxylase was also reduced 3 and 7 days after SAH. Superior cervical gangliectomy and intracisternal injection of 6-hydroxydopamine also reduced these three parameters. The uptake of 45Ca2+ by arteries from animals submitted to SAH was greater than if the blood vessels were from untreated cats. Lantanum brought about a less 45Ca2+ displacement in the arterial segments from untreated animals than in those from cats after SAH. These results suggest that SAH induces a transient adrenergic denervation as well as changes in the membrane of smooth muscle cell which increase the quantity of Ca2+ bound to it. All these modifications might be involved in the cause of chronic cerebral vasospasm that appears after SAH.

Animals↗
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 hemorrhage in severe head injury.

A series of 30 patients suffering posttraumatic intraventricular hemorrhage (IVH) after closed head injury is reviewed. Clotted blood and a mixture of blood and cerebrospinal fluid could be distinguished by computerized tomography (CT). Posttraumatic IVH was associated with diffuse brain lesions in most cases; intracerebral lesions with contusion, and subdural hematomas coexisted with posttraumatic IVH in eight and four instances, respectively. In two more cases, no CT abnormality other than IVH was noted. All patients in this series were in deep coma at the time of CT examination, and only seven survived. The early clinical findings, the site of ventricular hematoma, and the final outcome are analyzed.

Adolescent↗
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↗