STUDIES OF THE ANATOMY AND PATHOLOGY OF THE ORBIT IN CARCINOMA OF THEMAXILLARY SINUS AND THEIR IMPACT ON PRESERVATION OF THE EYE IN MAXILLECTOMY

Background. The periorbita has been traditionally regarded as the deci sive layer whose involvement in carcinoma of maxillary sinus indicates orbital exenteration. Anatomic texts depict that the orbital fat rest s on the periorbita. Our experience at surgical dissections has been d ifferent. Methods. Twenty-five patients underwent total maxillectomy f or advanced (T3-T4) carcinoma of the maxillary sinus with postoperativ e radiotherapy during a 15-year period between 1981 and 1995. In 11 pa tients, despite radiologic evidence of orbital invasion, and in 5 pati ents with infiltration of the periorbita, the eye could be preserved w ithout evidence of recurrence. In 6 patients who in addition underwent orbital exenteration, histopathologic evidence of tumor invasion of t he orbit was present in only one surgical specimen. Results. Clinicoan atomic studies have clearly shown the presence of a thin, distinct fas cial layer which surrounds the periocular fat and separates it from th e periorbita. Neither clinical examination nor imaging could predict o rbital invasion with absolute accuracy. Histopathologic examination of the surgical specimens shows that tumor infiltration of the eye is ra re. Conclusion. Periocular fat is surrounded by a thin fascial layer a nd is not in direct contact with the periorbita. Intraoperative decisi on making with respect to preservation of the eye is sometimes essenti al. (C) 1998 John Wiley & Sons, Inc.