Use of thermography to evaluate the optimum time for surgery after preoperative radiation.

At the University of Virginia Hospital, patients undergoing preoperative irradiation for carcinoma in the head and neck region are usually scheduled for surgery four to six weeks after completion of therapy. Since preoperative irradiation produces no significant difference in the operative difficulty or postoperative morbidity, it is assumed that the vascularity of the area has returned to the pre-treatemtn level. Thermography is being used to quantitatively gauge the amount of vascularity and thus, help predict the optimum time for surgery. Thermography is obtained at two-week intervals after a pre-treatment baseline and is carried out for eight weeks after completion of therapy. During therapy the vascularity as determined by thermography is noted to increase to a maximum at approximately three to four weeks or 3 to 4,000 rads. Following completion of treatment, the vascularity subsides gradually and returns to the pre-treatment level at four to six weeks after completion of therapy.