title: [Laser treatment of benign prostatic hypertrophy: the correlation of histologic results to nuclear magnetic resonance imaging].
abstract: Minimally invasive treatments for benign prostatic hyperplasia (BPH) are currently very controversial. Nd:YAG laser transurethral thermocoagulation of the prostate is the technique most frequently used. The objective of this study was to assess the correlation between the morphological effects observed and the changes visible on magnetic resonance imaging during this type or treatment in the human prostate, in order to evaluate the tissue effects obtained according to the power and the interaction time applied. In 10 patients requiring radical prostatectomy for urological cancer, visual laser ablation of the prostate (VLAP) was performed during the 10 days preceding the radical operation (range: 1 to 9 days). The entire gland was submitted to pathological examination in order to correlate the histological result with contrast magnetic resonance imaging performed in 6 patients, using a standard transrectal coil, 12 to 24 hours before complete resection of the prostate. The morphological examination showed zones of periurethral necrosis of variable volume, accompanied by extensive peripheral haemorrhage, containing vessels with a partially obliterated lumen. Contrast magnetic resonance imaging (T1) showed that laser-induced lesions had a low density appearance and were perfectly demarcated with peripheral heterogeneous and hyperdense zones. In contrast with the experimental investigations performed to date, we demonstrated a clearly delayed tissue effect. Our experience demonstrates that a period of several hours between laser treatment and removal of the operative specimen is not sufficient to evaluate the extent of laser-induced lesions. High resolution magnetic resonance imaging with a standard transrectal coil, sometimes combined with a multiple coil, is very valuable to assess the effects of laser.
authors.affiliation: Urologische Klinik and Poliklinik, Universitätsspital Zürich.
authors.forename: T
authors.initials: T
authors.lastname: Sulser
authors.forename: W
authors.initials: W
authors.lastname: Jochum
authors.forename: R A
authors.initials: RA
authors.lastname: Huch Böni
authors.forename: J
authors.initials: J
authors.lastname: Briner
authors.forename: G P
authors.initials: GP
authors.lastname: Krestin
authors.forename: D
authors.initials: D
authors.lastname: Hauri
mesh_terms: D000368:Aged; D000538:Aluminum Silicates; D003287:Contrast Media; D006470:Hemorrhage / Q000175:diagnosis / Q000473:pathology; D006801:Humans; D017075:Laser Coagulation / Q000379:methods; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D019060:Minimally Invasive Surgical Procedures; D009336:Necrosis; D009354:Neodymium; D011467:Prostate / Q000473:pathology; D011468:Prostatectomy; D011470:Prostatic Hyperplasia / Q000473:pathology / Q000601:surgery*; D013997:Time Factors; D014521:Urethra / Q000473:pathology; D015019:Yttrium
chemical_list: D000538:Aluminum Silicates; D003287:Contrast Media; D009354:Neodymium; D015019:Yttrium
vernacular_title: Traitement laser de l'hypertrophie bénigne de la prostate: corrélation du résultat histologique a l'imagerie par résonance magnétique nucléaire.