RE:RE:RE:RE:RE:RE:What a negative board now.....Hi Tom. In the NMIBC phase 2 trial Theralase is using green light delivered by the TLC-3400. According to the June 2017 news release:
"The TLC-3200 Medical Laser System (“TLC-3200”) combines laser light delivery and dosimetry via the TLC-3400 Dosimetry Fibre Optic Cage (“TLC-3400” or “DFOC”) to deliver laser light energy of a specific wavelength (“nm”) and energy density (“J/cm2”) to the bladder wall. The TLC-3200 then visibly signals the surgeon via a computer monitor when this irradiation has been achieved and to discontinue treatment.
The DFOC thus allows the surgeon to adjust Dose delivery in direct response to: bladder shape, volume and diffuse reflectance of the bladder wall, thus providing a consistent Dose to the patient’s inner bladder wall surface."
It seems that they underestimated the treatable area of the fully expanded bladders of the patients and therefore delivered an inadequate light dose.
In the intra-operative pdt for nsclc they are testing at Roswell Park the light delivery system is different. They delivered light using an optical surface applicator (OSA) which is decribed in the recent paper:
"In this paper we propose to activate TLD1433 with surface illumination using a recently developed optical surface applicator (OSA) [13]. The OSA was designed specifically for efficient light delivery in IO-PDT in the thoracic cavity. So far, the OSA has not yet been validated with TLD1433. The purpose of the present study was to test whether the OSA could be used to activate TLD1433 for the destruction of lung cancer cells in vitro before moving to in vivo studies. The OSA’s novel construction allows precise adjustments of the light irradiance (mW/cm2) and fluence that are key parameters for effective PDT [14,15]. The OSA includes optical fibers for laser light delivery, and dosimetry fibers for light measurements. A detailed description of the OSA can be found in Chamberlain et al. 2019 [13]. Briefly, the OSA is made of a flexible silicon-based mesh of interconnected spheres 10-mm in diameter with parallel channels that enable placement of optical fibers. The fibers are at fixed distance of 5 mm from the mesh surface. This design is expected to reduce the time of light administration with improved control of light irradiance and fluence [13]. Herein, we also present the first simulation of light irradiance and fluence propagation from the OSA."
In these tests both red and green light were tried and the green light was determined to be more potent. These were in vitro tests - the animal tests are yet to be reported on - they are probably already started.
Here's what the OSA looks like:
tomchoco wrote: Eog- can you explain the difference in what TLT is using in their Phase 2 as far as the light treatment from Lumeda's. From whaT I have read, the only stumbling block from Theralase was the amount of the dosage and everything else seems to be ok. Is Lumeda using the same type of light source as TLT for their initial trials on animals.