[Behavior of fatty tissue in frontal sinus obliteration].

The purpose of obliterating the frontal sinus is to provide a permanent solution to the underlying problem. The material of choice for obliteration is freshly removed abdominal fat. Using magnetic resonance imaging, one can assess the vitality of fat tissue in an obliterated frontal sinus without surgery. Eight patients ranging in age from 22 to 65 years underwent osteoplastic frontal sinus surgery with fat obliteration. The freshly implanted abdominal fat was postoperatively investigated using magnetic resonance tomography. The magnetic resonance examinations were carried out on a supraconductive 0.5 T Magnet (Gyroscan T S II, Philips Medicine Systems, Eindhoven, Netherlands) with a square head spool. We produced T1-weighted spin echo images (TR: 450-550 ms, TE: 20-25 ms), T2-weighted fast spin echo images or in double echo technique in transverse orientation (Tubo SE or TR-2000-2500 ms, TE: 50, 90 ms) and STIR sequences for fat suppression (TJ: 140 ms, TR: 1400 ms, TE: 30 ms). Our goal was to determine the time-dependent distribution of vital fat or fibrous tissue, development of necrosis, cysts, recurrences, inflammatory complications, or re-epithelization of the frontal sinus. Six to 24 months postoperatively, we found vital fat tissue in only three of eight cases. In the other five cases fat necrosis was present. The frontal sinus was filled by granulation tissue or fibrous tissue (once). It is not yet possible to determine when the fat changes to connective tissue. This process varies between individual patients. All eight patients were free of symptoms.(ABSTRACT TRUNCATED AT 250 WORDS)