An interstitial light assembly for photodynamic therapy in prostatic carcinoma.
AffiliationLaser Oncology Programme, CRC Department of Experimental Radiation Oncology, Paterson Institute for Cancer Research, Christie Hospital NHS Trust, Manchester, UK.
MetadataShow full item record
AbstractOBJECTIVE: To develop an interstitial laser light delivery system using multiple optical fibres for photodynamic therapy (PDT) in the treatment of prostate cancer. PATIENTS AND METHODS: A laser beam was divided equally with a 1 x 4 fibre splitter to deliver PDT simultaneously through four 2-cm long, flexible cylindrical optical diffusers. Biplanar transrectal ultrasonography (TRUS) and a template were used to position the optical fibres percutaneously. In vivo measurements of light penetration depth (1/micro[eff] ) in prostate tissue were made in seven patients, using a sheathed isoprobe to measure light fluence rates at varying radial distances from the diffuser. The prostate was fixed with stabilization needles to minimize displacement during needle placement. RESULTS: The mean (sd, range) micro(eff) in the prostates of the seven patients was 0.35 (0.07, 0.22-0.44) mm-1, which produced closely parallel slopes of light attenuation. However, there was up to a 10-fold variation in absolute light levels at the same diffuser-detector separation distances amongst the seven patients, probably caused by blood pooling around the diffuser light source. A similar problem around the isoprobe detector was overcome by sheathing the probe in clear plastic tubing. By stabilizing the prostate, the optical fibre positioning was precise to within 2 mm. CONCLUSION: Although this light delivery and TRUS assembly were developed for clinical PDT in the prostate, the same instrumentation can be used reliably for in vivo light-penetration studies. Haemorrhage was unpredictable and highlighted one of the main problems which needs to be overcome.
CitationAn interstitial light assembly for photodynamic therapy in prostatic carcinoma. 1999, 84 (7):821-6 BJU Int.
- Interstitial photodynamic therapy in the canine prostate.
- Authors: Lee LK, Whitehurst C, Chen Q, Pantelides ML, Hetzel FW, Moore JV
- Issue date: 1997 Dec
- Optimization of multifiber light delivery for the photodynamic therapy of localized prostate cancer.
- Authors: Whitehurst C, Pantelides ML, Moore JV, Blacklock NJ
- Issue date: 1993 Oct
- Novel flexible light diffuser and irradiation properties for photodynamic therapy.
- Authors: Selm B, Rothmaier M, Camenzind M, Khan T, Walt H
- Issue date: 2007 May-Jun
- In situ comparison of 665 nm and 633 nm wavelength light penetration in the human prostate gland.
- Authors: Lee LK, Whitehurst C, Pantelides ML, Moore JV
- Issue date: 1995 Nov
- Cylindrical fiberoptic light diffuser for medical applications.
- Authors: Mizeret JC, van den Bergh HE
- Issue date: 1996