The use of [ 99 mTc]methylene diphosphonate sequential scanning of experimental animals in evaluating the efficiency of wound healing in radical mastoidectomy

Abstract

The purpose of the present study was to evaluate by radiopharmaceuticals the efficiency of wound healing in radical mastoidectomy, using a graft of bone paste plus concentrated fibrinogen in the mastoid cavity. Twelve vervet monkeys ( Cercopithecus pygerethrus) were included in the experiment. The surgical procedures were the following:- 1. (A) The mastoid cavity was left without obliteration. And alternatively, the mastoid cavity was obliterated with 2. (B) fibrin adhesive only, 3. (C) bone paste only, 4. (D) fibrin adhesive and bone paste. The healing was controlled for 3 months by frequent [ 99 m Tc]methylene diphosphonate ([ 99 m Tc]MDP) scintigraphy and radiography of the skull. Histological slices were taken from a concomitant group at 4 weeks and 3 months after the surgical intervention. The results as confirmed by macroscopical viewing and x-rays demonstrated bony regrowth only with procedures (C) and (D). Greatly enhanced radionuclide uptake with respect to (A) and (B) also became apparent from the two last procedures, with bone activity peaking at about 3 weeks and continuing significantly for up to 60 days. Scintigraphically (C) and (D) demonstrate no meaningful differences between them. Histologically a better quality bone was indicated following procedures (D). This is possibly due to accelerated vascularisation, as is known to result from the fibrin adhesive.