Intrauterine light delivery for photodynamic therapy of the human endometrium.
Photodynamic therapy is currently being evaluated as a minimally invasive procedure for endometrial ablation not requiring anaesthesia. Light penetration depths at 630, 660 and 690 nm and the optimal configuration of intrauterine light-diffusing fibres were determined in 14 human uteri to assist in the design of a light intrauterine device. Post-menopausal ex-vivo uteri showed a significantly lower light penetration depth than pre-menopausal uteri. With a single central diffusing fibre inserted, the fluence rate measured in the uterine wall at the most remote point of the cavity decreased to 1.1 +/- 0.4% of that measured at closest proximity, whereas it decreased to only 40.0 +/- 9.0% with three fibres. Distension of the uterine cavity with 2 ml of an optically clear fluid increased the fluence rate at the fundus between the fibres at a depth of 2 mm by a factor of 4. We conclude that in normal-sized pre-menopausal uterine cavities, three diffusing fibres will deliver an optical dose above the photodynamic threshold level at a depth of 4 mm, even in the most remote areas, in < 30 min without causing thermal damage. For distorted and elongated cavities, either slight distension of the cavity or the insertion of a fourth diffusing fibre is required.
Fehr
M K
MK
Beckman Laser Institute and Medical Clinic, University of California, Irvine 92715, USA.
Madsen
S J
SJ
Svaasand
L O
LO
Tromberg
B J
BJ
Eusebio
J
J
Berns
M W
MW
Tadir
Y
Y
D000328:Adult; D004717:Endometrium / Q000187:drug effects* / Q000528:radiation effects*; D004867:Equipment Design; D005069:Evaluation Studies as Topic; D005260:Female; D005336:Fiber Optic Technology / Q000295:instrumentation; D006801:Humans; D008027:Light; D008593:Menopause; D008875:Middle Aged; D010778:Photochemotherapy / Q000295:instrumentation / Q000379:methods*