Laser coagulation

Peyman, G.A., and D. Bok. 1972. Peroxidase diffusion in the normal and laser-coagulated primate retina. Invest Ophthalmol 11 35. 

Lentigines and keratoses should be treated by another method in parallel with AHA peels. There are other, more efficient, techniques to treat these problems liquid nitrogen, dry ice, Only Touch peel, intense pulsed light (IPL), laser, etc. Dr Robert Vergereau (France) compared the use of dry ice, Erbium laser, Q-switched laser, coagulation and Only Touch peel. He concluded that If all these methods are satisfactory, in my opinion, the technique using trichloroacetic acid is the most beneficial . 

The most recent study used interstitial laser coagulation in an in vivo canine prostate model.Histological damage to the prostate was correlated to two thermal models one was predictive using a threshold temperature of 324 2 K, and the other using a thermal dose of approximately 200 minutes at 316 K. Representative thermal images are shown in Fig. 19. 

Fig. 19. MR-derived thermal maps during interstitial laser coagulation studies in an in vivo canine prostate gland. The thermal maps are overlaid on a magnitude (localizer) image. The heated areas can be seen as the light coloured annulus growing in size with time (left-right). (Reprinted from ref. 270 by permission of John Wiley Sons, Inc. Copyright 2000 John Wiley.)...

Laser coagulation is performed using a Neodym-ium-YAG laser (Fig. 2.3.1) (Dornier MediLas 5060 or Dornier MediLas 5100) with a specially developed flexible laser applicator. Furthermore an application kit for percutaneous treatment was developed and optimized for our purposes. 

Peters RD, Chan E, Trachtenberg J, Jothy S, Kapusta L, Kucharczyk W, Henkelman RM (2000) Magnetic resonance thermometry for predicting thermal damage an application of interstitial laser coagulation in an in vivo canine prostate model [In Process Citation]. Magn Reson Med 44 873... 

Albrecht D, Germer CT, Isbert C, Ritz JP, Roggan A, Muller G, Buhr HJ (1998) Interstitial laser coagulation evaluation of the effect of normal liver blood perfusion and the application mode on lesion size. Lasers Surg Med 23 40-47... 

Verhoef C, Kuiper JW, Heisterkamp J et al (2003) Interstitial laser coagulation with temporary hepatic artery occlusion for patients with cirrhosis and irresectable hepatoma. Br J Surg 90 950-955... 

Laser coagulation was performed using a neodym-ium-YAG laser (Dornier MediLas 5060 or Dornier... 

Avni FE, Bali MA, Regnault M et al (2002) MR urography in children. Eur J Radiol 43 154-166 Beck M, Graf C, Ellenrieder B et al (2005) Long-term outcome of kidney function after twin-twin transfusion syndrome treated by intrauterine laser coagulation. Pediatr Nephrol 20 1657-1659... 

Within the last decade thermal ablations have been developed and clinically improved. Different technologies have been evaluated like magnetic resonance-guided laser-induced thermotherapy (MR-guided LITT), radiofrequency ablation (RF), microwave and cryotherapy. For this reason, there has been great interest in further developments of interstitial procedures such as laser coagulation or radiofrequency ablation over the last few years. 

In most experiments the smallest amount of electrolyte needed to coagulate the sols measured after 2 hours standing was chosen as the CCC. When using HC1, this point is the critical coagulation pH. A constant temperature water bath was used for temperature different than 23°C. The pH values were measured with a Beckman Model 96A pH meter and a Fisher combination electrode. The electrophoretic mobility measurements were made with a Laser Doppler Electrophoresis apparatus. These experiments were performed by Mr. J. Klein of the Chemistry Department, Syracuse University. 

Confocal laser scanning microscopy can be used in conjunction with microwave heating for examining the three-dimensional structure and cellular interrelationships in sections of paraffin-embedded tissues (Boon and Kok, 1994). Tissues are fixed with Kryofix, a coagulant fixative containing 50% ethyl alcohol and polyethylene glycol (PEG molecular weight 300) for 90 sec in a microwave oven. The use of thick paraffin sections (15 (xm) and fluorescently labeled antibodies is preferred. 

Combination therapy The use of local-interventional procedures is restricted to a maximum tumour size of 5 cm in diameter. Therefore, a combination of two local techniques is seen as promising. The joint application of PEI and TAB has proved its efficacy for some time. (177) Similarly, there have been reports about the successful use of TACE following laser thermal ablation. (136) Further encouraging options include a combination of TACE and RFTA, TACE with microwave coagulation (149) or TACE with cryotherapy. Using TACE, the size of the HCC can be reduced in some cases, making it possible to carry out subsequent ablation with better results. 

Laser-induced thermotherapy (LITT) In 1983, S.G. Bown applied this technique for the first time as minimally invasive percutaneous ablation therapy. By means of quartz fibres, Nd YAG laser light (1,064 nm) is conducted directly into the tumour via a probe. The laser light is converted into heat, thus causing a coagulation necrosis of the tumour. Necroses of up to 4(-5) cm in diameter may result. Probe application is carried out by MR-guiding this technique is also used for monitoring success. The procedure is considered to be both safe and efficacious. (45, 129) (s. p. 800)... 

C. T. Germer, A. Roggan, J. P. Ritz, C. Isbert, D. Albrecht, G. Muller, and H. J. Buhr, Optical Properties of Native and Coagulated Human Liver Tissue and Liver Metastases in the Near-Infrared Range, Lasers Surg. Med., 23(4), 194-203 (1998). 

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