PHOTONICS INTERVIEW with Prof. Dr. Lubatschowski from the Laser Zentrum Hannover

August 26th, 2010

Prof. Dr. Lubatschowski is head of the Biomedical Optics Department at the Laser Zentrum Hannover and CEO of the Rowiak GmbH, a spin-off of the Laser Zentrum in 2004, which develops laser systems for micro-processing of biological tissue.

 1. Lasers have been used in medicine for many years now, and new applications are continually being found. What are the most recent practical applications?

 Prof. Dr. Holger Lubatschowski: A new method of correcting defective vision is presently being tested by the company Carl Zeiss Meditec. Up to now, the so-called LASIK method has been used to cut a 100 µm layer of the cornea of the eye, using either a scalpel or a femtosecond laser. Following this, an excimer laser is used to model the surface of the eye lens by removing cell layers to correct vision defects. The new process by Zeiss aims at employing a femtosecond laser, making a one-step process possible.

Femtosecond lasers will also soon be used for cataract operations. Currently, ultrasound and a hollow needle are used to shatter and siphon off the hardened, grey lens. Subsequently, an artificial lens is inserted into the capsule. The use of a femtosecond laser should make the operation simpler, less invasive and more precise. The artificial lens can then be more precisely positioned, and the seeing ability of the patient can thus be improved. The cataract operation is the most commonly performed operation, and the market potential for this new method is correspondingly high.

 2. The laser often is used as an alternative to established methods. Which therapies are only possible using the laser?
 
Prof. Dr. Holger Lubatschowski: The correction of defective vision using refractive cornea surgery (LASIK) is impossible without the laser.

Diabetics often have an increased growth rate of very small blood vessels in the retina. They threaten to be a disturbance for the photoreceptor cells, and can lead to blindness. The laser can be used to atrophy these blood vessels, without having to surgically open the eye.

Retina ruptures can also be atrophied using thermal effects. This is popularly referred to as retina welding. Actually, the laser makes a controlled scar, which encloses the part of the retina which is detached.

After a cataract operation, the posterior lens capsule may become clouded. A pulsed laser can be used to "shoot away" the cloudiness. Here too, the scalpel doesn't have to be used.

 3. Nd:YAG and CO₂ lasers have been used in medicine for some tine now. Will they be replaced at least in some areas by less expensive diode lasers?

Prof. Dr. Holger Lubatschowski: The diode laser is already in standard use in many areas of application. In part, it has already replaced the Nd:YAG laser, and in other cases has created new applications. There is presently no real alternative for the CO2 laser. The Er:YAG laser can be used for some applications.
 
4. Do doctors need special training if they use a laser?

Prof. Dr. Holger Lubatschowski: No, most of the time they only need to follow the manufacturer's instructions, like for many medicinal instruments. However, there are groups in the field of ophthalmology, especially in refractive surgery, which require extra training, and most surgeons follow this course.

 5. How are the so-called soft lasers for use at home connected to medicinal lasers?

Prof. Dr. Holger Lubatschowski: Lasers often are considered to be something very special. They can be used to achieve a placebo effect. My personal opinion is that this is the only effect these kinds of lasers can be used for.
 
6. What are the most interesting, future applications in laser medicine?

Prof. Dr. Holger Lubatschowski: The femtosecond laser has already created a new era in the field of ophthalmology. After the unbelievable success in the field of corneal surgery, this laser will probably also be used for cataract surgery.

I could imagine that in the future, this laser could also be used to treat presbyopia by making hardened lenses more flexible. That would be a gigantic market, considering that everyone older than 45 begins to experience presbyopia.

7. Apart from your activities at the LZH, you are CEO of the spin-off Rowiak. What exactly does Rowiak do?

Prof. Dr. Holger Lubatschowski: I founded the Rowiak GmbH in 2003. Rowiak develops and produces innovative laser systems for non-invasive treatment of biological tissue and cells, as well as for materials for use in laser surgery. Our laser units are used mainly in medicinal and pharmaceutical laboratories, in biotechnology and genetics, or in cell and molecular biology.
Recently we began cooperative work with the LZH to create a prototype unit for correcting presbyopia.

Source: World of Photonics News.