Biomedical subjects

J F Vieira

Publications and source records attributed to J F Vieira.

4 recordsLinked to original sources

PubMed1988

Impedance measurements of the spinal cord of man and animals.

The measurement of electrical impedance of normal and pathologic tissue has not been fully utilized in neurosurgery. This is a report of electrical impedance measurement in the central nervous system of both man and animals. We show the results of the laboratory study done in animals, in the brain and in the spinal cord as well. Also we show the clinical experience of the impedance recordings in the DREZ procedure for some chronic pain conditions, correlating the measurements at the time of the operation with normal conditions, with comments about the findings.

Animals↗

PubMed1988

Dorsal root entry zone coagulation for intractable sciatica.

Chronic back and leg pain which is unresponsive to medical and/or surgical treatment is a common and difficult neurosurgical problem. Twelve patients with this condition underwent dorsal root entry zone coagulation of that region of the conus medullaris which correlated with the pain. Only 2 patients had a favorable result. The implications of this finding are discussed.

Adult↗

PubMed1987

Electrical impedance recording for localization in functional neurosurgery of the spinal cord and lower brain stem.

Functional neurosurgery aims to modify or abolish neural messages. Established techniques use confirmatory electrical stimulation prior to ablation and require local anesthesia. Recently developed procedures take place under general anesthesia increasing the chance of damage to adjacent neural structures with postoperative morbidity. We describe a laboratory study correlating changes in measured electrical impedance with transition from white to grey matter in the brain and spinal cord of two mammalian species; this has not previously been easy to undertake, nor felt reliable. Impedances can now be measured simply and reliably. This study confirms our operating theater experience. We recommend that when stimulation cannot be used, impedance can and should be utilized to indicate the need for an electrode to be resited.

Animals↗

PubMed1986

Sacrococcygeal rhizotomy for perineal pain.

Chronic pain in the perineum is a difficult neurosurgical problem. This article evaluates the effectiveness of sacrococcygeal rhizotomy in 28 patients who had cancer-related pain or coccydynia, underwent rhizotomy, and were followed for an average of 3 years. Good pain relief was obtained in 53% (10 of 19 patients) with malignant pain, as opposed to 22% (2 of 9 patients) with nonmalignant pain. Sacral rhizotomy is a reasonable treatment for cancer-related perineal pain, but it is ineffective for coccydynia and other benign perineal pain problems.

Adult↗