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K Maravilla

Publications and source records attributed to K Maravilla.

25 records · Page 2Linked to original sources

Computerized tomographic scan and gunshot wounds of the head: indications and radiographic findings.

The authors document their experience with the computerized tomographic (CT) scanner for evaluating gunshot wounds of the head. Only those patients who were considered to be operative candidates and who were neurologically stable were scanned. In the postoperative period, patients who were not scanned preoperatively and those whose condition did not improve were also scanned. In the preoperative period the CT scanner is useful for identifying and localizing missile tracks, bony and metallic fragments, intra- and extraparenchymal hematomas, intracranial air, and brain swelling. In the postoperative period the CT scanner may demonstrate retained bone fragments, edema, brain abscess, and intracranial air. The limitations of the CT scan in evaluating gunshot wounds include an inability to define vascular lesions suchas traumatic aneurysms and post-traumatic spasm. Metallic scatter from missile fragments may render certain CT cuts uninterpretable. In addition, the CT scan may appear minimally abnormal in spite of immediate and irreversible injury caused by a shock wave transmitted to brain stem structures. The CT scanner has superceded angiography as a diagnostic tool for evaluating gunshot wounds of the head because it is noninvasive and rapid, allows visualization of the entire head, can resolve very small lesions that produce little or no mass effect, can help to determine the nature of intracranial lesions and may quantitate the amount of hemorrhage and edema. Because it enables physicians to visualize intracranial structures in three dimensions, the CT scan may precisely define missile tracks and contiguous lesions in a manner not heretofore possible with other diagnostic modalities. Thus, it is invaluable for the rational planning of surgical therapy.

Brain Injuries↗

Serial computerized tomographic scanning and the prognosis of severe head injury.

Serial (two or three) computerized tomographic (CT) scans were performed on a series of 58 patients with severe head injury. The protocol called for scans to be done upon admission and on Days 3 and 7 after injury. New lesions (i.e., lesions not visualized on the initial CT scans but appearing on subsequent scans) were a frequent finding, occurring in over half of all patients. For the purposes of this study a new lesion was classified as edema involving two or more lobes, extra-axial hematoma, parenchymal hemorrhage, or infarction. Significant correlation was found between good outcome and the absence of new lesions and between bad outcome and the development of new lesions (p less than 0.001). Several patients did well in spite of the development of new lesions, but these patients were unique in that most had small, unilateral parenchymal hematomas located at or near the frontal or temporal poles. In most cases, patients who did poorly in spite of not developing new lesions had severe injuried visualized on their initial scans (massive intracerebral hematoma, hemorrhage of the corpus callosum) or succumbed to medical complications. The pertinent literature is reviewed, and other CT findings associated with a poor prognosis are noted. The authors suggest that serial CT scanning may be used to make prognostic assessments in severely head-injured patients and may be of value in increasing the confidence in and accuracy of assessments made on clinical grounds alone. (Neurosurgery, 5: 566--569, 1979).

Brain Edema↗

Dexamethasone and severe head injury. A prospective double-blind study.

A prospective double-blind study of the effects of dexamethasone administration on the outcome of patients with severe head injuries was performed. Patients were stratified for severity of neurological injury and were treated with placebo, low-dose dexamethasone (16 mg/day), or high-dose dexamethasone (96 mg/day) for a period of 6 days. Outcome was evaluated at 6 months following injury. Of the 76 patients available for analysis, a good outcome was achieved in 37% of placebo-treated patients, 44% of low-dose-treated patients, and 29% of high-dose-treated patients. These differences are not statistically significant. Similarly dexamethasone administration had no statistically significant effect on intracranial pressure patterns or serial neurological examinations during hospitalization. Gastrointestinal bleeding occurred in only one patient. Good outcome was associated with age under 10 years, lighter depth of coma on admission, and the preservation of brain-stem reflexes upon admission. A recalculation of data in previous clinical series purporting to show an improvement in outcome as a result of corticosteroid therapy shows no significant difference in outcome when steroid- and placebo-treated patients are compared. In our series, 90% of all deaths were caused by recurrent intracranial hematomas, medical complications, or diffuse brain injuries with parenchymal hemorrhage and tissue disruption -- causes of death which cannot be affected by corticosteroid therapy. The study suggests that dexamethasone in either high or low dosages has no significant effect on morbidity and mortality following severe head injury.

Adolescent↗

Sectional neuroanatomy of the upper limb I: brachial plexus.

This series of three articles is structured to provide anatomically accurate functional schematics of the motor and sensory innervation of the shoulder and upper limb. This first paper provides radiographically oriented sagittal sections through the brachial plexus to assist in directly identifying a plexal lesion. A coronal schematic of the brachial plexus and summary table allows prediction of unique patterns of denervation from 19 lesion sites. Correlation between the lesion and the denervation pattern ensures the lesion is, in fact, clinically significant. The next two articles will present a color-coded atlas that allows the radiologist to quickly assess patterns of denervated muscles and thereby indirectly localize the lesion site. Thus, the three articles can be used together to predict the clinical picture for a given nerve lesion or extrapolate lesion location when a constellation of denervated muscles are seen on an upper limb magnetic resonance imaging or electromyographic study.

Arm↗

Magnetic resonance imaging of the spinal cord in spinal dysraphisms.

Magnetic resonance imaging (MRI) was performed 49 times in 42 patients with spinal dysraphism. Scoliosis and a changing neurological picture were the primary indications. Spinal cord anomalies included hydromyelia, diastematomyelia, lipoma, thickened filum terminali, and spinal cord atrophy. All but one patient exhibited Arnold-Chiari malformation. Twenty-two of the 42 patients had computed tomography (CT) scans, myelograms, or operations that corroborated the 41 MRI findings. Three false-positive MRI findings of hydromyelia and no false-negative studies were observed. MRI is a noninvasive investigative technique that provides more information than myelography or CT in defining spinal cord anatomy in spinal dysraphism.

Arnold-Chiari Malformation↗

Magnetic resonance imaging findings and correlations in spasmodic dysphonia patients.

A sample of 19 spasmodic dysphonia (SD) patients was selected from a larger population of such patients to undergo magnetic resonance imaging (MRI), auditory brain stem response (ABR) testing, speech analysis, and extensive physical examination. Six patients had abnormal spin-echo MRI findings, ranging from infarcts within the basal ganglia to demyelinating lesions within the supralateral angles of the lateral ventricles. A weakly positive correlation was noted between the abnormal MRI findings and an abnormal ABR. The lack of a significant correlation between the MRI findings and other predictors of brain stem and midbrain disease, and the current spatial resolution limitations of MRI, suggest that we are visualizing the associated lesions rather than the actual foci of SD. The range of MRI findings is consistent with the concept that SD is a voice disorder in a heterogeneous patient population.

Adult↗