1. From the Departments of Clinical Medical Sciences (M.A.G., D.N.) and Paraclinical Sciences (S.M.), Faculty of Medical Sciences, Eric Williams Medical Sciences Complex, Building 39, First Floor Uriah Butler Highway, Champ Fleurs, University of the West Indies, St Augustine Campus, St Augustine, Trinidad; and Departments of Urology (A.P.R., K.S.) and Radiology (C.M.G., M.D.M., R.B.), San Fernando General Hospital, Paradise Pasture Independence Avenue, San Fernando, Trinidad.