Today, surgical interventions with lasers are nothing out of the ordinary. Since the cutting and welding tool found its way into medicine from the plastics processing industry in the 1980s, its range of applications has steadily expanded. The laser is used particularly frequently in ophthalmology. But lasers are also used for skin diseases or in urology.
Laser treatment – light and heat
In laser treatment, doctors and physicians use the conversion of light into heat in the tissue. The energy particles of the light, the photons, are accelerated by the decay of an added noble gas. Depending on which gas is used, the wavelength of the light produced varies greatly and different types of tissue can be treated. The gas argon, for example, is used in the argon laser to obliterate vessels because it delivers its energy particularly well to the red blood pigment hemoglobin. During treatment with the CO2 laser, the tissue absorbs a particularly large amount of energy, which is why this laser is particularly good at cutting and ablating tissue.
Eyes open.
The laser works particularly finely in the area of eye disorders. Short-sightedness, long-sightedness or astigmatism can be treated well with laser surgery when conventional corrections are not sufficient. The two most important procedures are LasIK (“laser in situ keratomileusis”) and LasEK (“laser epithelial keratomileusis”). In laser treatment, the laser beam partially “abrades” the cornea, altering its refractive value. Although there is a higher risk of scarring, the LasIK method has high and sustained success rates of 70% to 80% for values as low as -10 diopters.
LasIK method
During the procedure, the cornea is marked and the eyeball is aspirated with a ring so that the eye does not see anything for a few seconds. Then, a very thin layer (lamella) is cut off with a fine plane, leaving a small ridge of tissue. The cut layer is folded over and the actual ablation of the tissue inside the cornea with the excimer laser can begin. The areas are then rinsed well and the folded back flap is reaspirated from the cornea. This is followed by eye drops, dressing or bandage lens. The procedure is described as almost painless and is performed on an outpatient basis. The operation lasts less than 15 minutes and is controlled already 1-2 hours after the procedure. The eye should not be rubbed for the first few days afterward to avoid displacement of the lamella. Those who work in very dusty environments must refrain from doing so for 2 weeks after the surgery. Basically, the new visual acuity must first stabilize; therefore, one should refrain from driving in the dark for some time after the procedure.
LasEK method
The LasEK treatment is somewhat gentler than the LasIK method. Here, the outer, extremely thin layer of cornea is peeled off with alcohol and rolled to the side before being treated with the excimer laser, as in LasIK. LasEK is used primarily for patients with thinner corneas. The complication rate of the treatment is 1-4%. Only a few cases of ocular perforation due to the laser have been reported worldwide. The treatments are usually not covered by health insurance. Retinal detachments can be successfully rewelded with the laser, and new vascular growths in diabetic eye patients can be sclerosed with the argon laser. However, the laser is not used for chronic progressive corneal diseases or systemic immune diseases.
Psoriasis and vein problems
While laser treatment is widely established in ophthalmology, an interesting new treatment option has been developed for patients with psoriasis using an excimer laser. The laser light is applied to the plaques of the affected skin; the dosage is precisely determined. Since the light is applied selectively and in a targeted manner, the spread can be stopped immediately, and a small area can be made to disappear after a few treatments – usually less than 10 irradiations. owing to the “pinpoint accuracy” of the laser, unaffected parts of the body are spared. At the next visits – depending on the results – the doses are increased or reduced and thus adapted to the given healing. As a rule, one treatment per week is sufficient. In the initial period, up to two treatments per week are also possible.Treatment costs range from 100 to 200 euros per session, but are based on the size of the affected skin region and the light dose to be applied. They are usually covered only by private health insurance.
Aftercare is precaution
With the excimer laser technique, aftercare of psoriasis is also possible. After the psoriasis has healed accordingly, the patient presents again at more or less regular intervals. At the beginning psoriasis does not appear on large areas, but initially on small areas. This means that foci the size of a penny appear either in healed areas or in new areas. If these foci are treated in time with a light UVB laser, a single irradiation is sufficient until they disappear completely. This makes it possible to perform aftercare for psoriasis by means of precisely targeted laser treatment. In this case, aftercare is precaution, so that long intervals free of appearance are possible. Compared to the costs of the initial treatment, the follow-up costs for aftercare are rather low at about 30 euros. Ineffective ointment therapy can be dispensed with, and preparations containing cortisone are not used.
Removal of spider veins – still a young procedure.
Spider veins, the very thin and fei n branched superficial vein dilatations, can also be treated with laser beams. However, completely satisfactory results are not yet available for this, so that in many cases multiple retreatments are necessary. Because lasers have not been used to treat spider veins for very long, sufficient empirical data are still lacking.
Well established in angiology
In contrast, the use of lasers in angiology, or vascular medicine, is quite common. It is precisely because of the gentle method of dissolving clots that they can be used to good effect. In this case, the thin examination tube is extended with a laser head during an angiography. The laser can then work directly on site with pinpoint accuracy without damaging the surrounding tissue. Interventions with the scapell are not necessary for this.
Use in urology
Laser treatments are also performed endoscopically in urology. Smaller prostate enlargements can be treated by inserting a so-called “resectoscope” into the urethra. The laser also directly removes trapped ureteral stones or bladder stones: The high-energy light pulses create a shock wave that shatters the calculi. In addition, benign growths on the penis in the area of the glans can be removed with a CO2 laser. However, the treatment of prostate cancer is not possible in this way. The application possibilities of modern lasers are increasing, and the devices are constantly being improved and expanded. The combination of modern imaging techniques, medical data processing and information technology also leads to new procedures in laser treatments. Whether and to what extent laser treatment is possible and useful for an individual disease should be clarified with the attending physician.
