Diagnostics & Imaging Week

It should come as no surprise that knowing where the tumor is, and being able to avoid nearby organs and healthy tissue, is an important part of any cancer treatment. Several medtech companies are working toward this goal by developing image-guided systems to help clinicians locate the tumor before administering radiation therapy.

One company, Calypso Medical (Seattle), even has a GPS-like system designed to track the movement of cancerous tissue during radiation therapy. And another company, Visualase (Houston) has a system that puts a spin on the former technique by treating solid tumors using laser light to destroy the affected tissue through heat.

A 2005 spinoff from BioTex (Houston), Visualase uses image-guided technology, such as MRI, to place fiber optics directly into the tumor and deliver laser light energy within the desired region of treatment. Absorption of light energy by the tissue volume results in volumetric heating, which ultimately leads to thermal destruction of the tumor, according to the company. The method is called laser-induced interstitial thermal therapy (LITT). The advantage of LITT therapies is that the energy is applied directly to the tumor rather than passing through surrounding normal tissue, Visualase said.

"This little fiber goes in and it's very directed, very focused, the doctor's in control of what he's ablating and it's very cost-effective," Steve Price, the company's VP of sales and marketing, told Diagnostics & Imaging Week.

The minimally invasive treatment can be done in an outpatient setting or in the hospital, Price said, and patients can undergo multiple treatments with minimal side effects. In the company's clinical trials in Paris there were no side effects, pain, or treatment-related problems reported, he said. The company is now in clinical trials in the U.S. for multiple applications of its LITT treatment.

Visualase believes its system is going to reduce healthcare costs by minimizing surgical complications, reducing recovery time and hospital stays.

Last year Visualase reported that it, along with BioTex and the Assistance Publique - Hôpitaux de Paris healthcare network had enrolled and treated the first six patients in a pilot, Phase I study, with the objective to demonstrate the safety of its MRI-guided laser thermal ablation technique for the treatment of brain metastasis. An independent review after the first three treatments found that the technique was safe and that the trial should be allowed to progress to the next level, in which larger tumors from additional sources could be included, the company noted.

The Visualase thermal therapy system uses the company's cooled laser application system (V-CLAS) fiber, a PhoTex laser, and the Envision workstation in a cohesive system, the company said. Its V-CLAS delivers optical energy through a diffusing tip fiber optic applicator cooking the tissue from the inside out, according to Visualase.

The diffusing tip is used with a cooling catheter to circulate a cooling fluid to cool the diffusing fiber and to remove heat from tissue adjacent to the applicator, the company said. The Envision workstation provides real-time visualization of the thermal damage front as it is being created.

By processing data from compatible MRI sequences, the Envision computer is able to calculate the temperature at each point within the target volume and display this information on color-coded images during treatment, Visualase said. Because the workstation acquires MR images as they are generated, the system allows immediate manipulation, examination, or calculations based on image data.

Visualase is a private company, funded by government grants, including a $750,000 award from the State of Texas Emerging Technology Fund.

When asked about the company's exit strategy, Price told D&IW that Visualase has attracted a lot of interest from venture capital firms.

"I see us having several exit strategies," Price said, mentioning that being bought out by a bigger company is one option and that going public also is a possibility. "We're open for suggestions, but we are having a lot of interest in the company."