PubMed Health⌕ Search

Biomedical subjects

U P Kalokhe

Publications and source records attributed to U P Kalokhe.

4 recordsLinked to original sources

Method for reducing scatter radiation dose to the contralateral breast during tangential breast irradiation therapy.

PURPOSE: To reduce scatter dose to the contralateral breast during tangential breast irradiation therapy. MATERIALS AND METHODS: The authors used a 4-mm-thick commercially available vinyl-coated flexible lead shield that contains a compound of vinyl resin and lead powder of 1-mm-equivalent lead density. Contralateral scatter dose was measured at 5 cm outside the geometric field edge and along the field axis, with and without use of block trays and different wedges. RESULTS: On the skin, contralateral scatter dose from the medial tangential beam was reduced from about 15% to about 5% of the therapeutic dose delivered to the treated breast. The bulk of scatter dose was absorbed within the first 2 cm of breast tissue. CONCLUSION: Reduction in unwanted scatter dose to the contralateral breast is in accord with the philosophy of keeping radiation exposure as low as reasonably achievable and might be of most benefit for young patients.

Breast↗

Monitoring the radiation dose to a multiprogrammable pacemaker during radical radiation therapy: a case report.

Multiprogrammable pacemakers, using complimentary metaloxide semiconductor (CMOS) circuitry, may fail during radiation therapy. We report about a patient who received 6,400 cGy for unresectable carcinoma of the left lung. In supine treatment position, arms raised above the head, the pacemaker was outside the treated area by a margin of at least 1 cm, shielded by cerrobend blocking mounted on a tray. From thermoluminescent dosimeter (TLD) measurements, we estimate that the pacemaker received 620 cGy in scatter doses. Its function was monitored before, during, and after completion of radiation therapy. The pacemaker was functioning normally until the patient's death 5 months after completion of treatment. The relevant electrocardiograms (ECGs) are presented.

Aged↗

Scatter dose from tangential breast irradiation to the uninvolved breast.

Thermoluminescent dosimeters (TLDs) were used to measure scatter radiation to the uninvolved breast in 30 patients who received tangential breast or chest-wall radiation with a technique in which the deep edges of the tangential fields were aligned. In most patients, measurements were made during the 1st week of radiation therapy, after port radiographs were obtained to ensure proper field position and accurate alignment of the posterior tangential field edges. Phantom measurements were made simultaneously with TLD measurements to systematically assess the scatter dose as a function of the wedging, number of fields, type of accelerator, beam energy, and bolus used in each treatment. For most patients, the scatter dose to the contralateral breast at a point on the skin 5 cm outside the edge of the medial beam was 8%-13% of the prescribed dose. However, higher doses (up to 36% of the therapeutic dose) were recorded in some patients.

Breast↗