跳至主要内容

First Intraluminal Temperature Measurement during Ho:YAG-Laser Exposure at an In-Vitro URS

Read  full  paper  at:
http://www.scirp.org/journal/PaperInformation.aspx?PaperID=52946#.VK3gj8nQrzE

ABSTRACT
Introduction: The laser is a high energy instrument which can melt metals like nitinol. So it is very important to know under which conditions it is dangerous to perform an endourologic lithotripsy. We measure the temperature increase during laser exposure in an underwater in-vitro ureter model. For comparison, temperatures with and without irrigation and with different distances from the laser fiber to the thermometer are measured. Materials and Methods: We used the Ho:YAG-laser (Vera PulseTM, Coherent) with a 365 μm laser fiber. The settings of the laser were 0.6 J with a frequency of 5 Hz which is the minimum setting for that type of laser. The experimental setup was closely aligned with the clinical situation. A metal container was filled with 0.9% sodium chloride (NaCl) solution (Temp. 36.8°) and a catheter with an inner diameter of 4 mm was attached to the rim of the container. The tip of the thermometer was attached inside the catheter through a waterproof hole. The laser fiber was guided by means of a rigid URS video device (11.5 F). We had four different settings during the measurement: 1) Distance of 0.5 cm between the laser and the thermometer; without irrigation, 2) Distance of 0.5 cm between the laser and the thermometer; with irrigation, 3) Distance of 1 cm between the laser and the thermometer; without irrigation, 4) Distance of 1 cm between the laser and the thermometer; with irrigation. Results: The maximum overall temperature was recorded in the 1) and 3) setting, both featuring no irrigation. The maximum temperature was ~50°C in both settings, with the 1) setting reaching the maximum temperature after 50 seconds and hence approximately twice as fast as the 3) setting. During measurements with a NaCl solution flow we couldn’t detect any noticeable increase in temperature, neither at short nor at long distance between the laser fiber and the thermometer. Conclusion: There is a relevant heating in the ureter beside an endourologic lithotripsy. In our model we could reproduce a maximum heating until ~50°C without irrigation and no heating with irrigation. Without irrigation there is a relevant bubble formation which should be an indicator for the surgeon to stop lithotripsy due to a temperature increase which could harm surrounding tissue.
 
Cite this paper
Cordes, J. , Nguyen, F. and Sievert, K. (2015) First Intraluminal Temperature Measurement during Ho:YAG-Laser Exposure at an In-Vitro URS. Open Journal of Urology, 5, 1-5. doi: 10.4236/oju.2015.51001.
 
References
[1]Marks, A.J. and Teichman, J.M. (2007) Lasers in Clinical Urology: State of the Art and New Horizons. World Journal of Urology, 25, 227-233. http://dx.doi.org/10.1007/s00345-007-0163-x
 
[2]Rosette, J., Denstedt, J., Geavlete, P., Keeley, F., Matsuda, T., Pearle, M., Preminger, G. and Traxer, O. (2014) The Clinical Research Office of the Endourological Society Ureteroscopy Global Study: Indications, Complications and Outcomes in 11,885 Patients. Journal of Endourology, 28, 131-139.
http://dx.doi.org/10.1089/end.2013.0436
 
[3]Piergiovanni, M., Desgrandchamps, F., Cochand-Priollet, B., et al. (1994) Ureteral and Bladder Lesions after Ballistic, Ultrasonic, Electrohydraulic, or Laser Lithotripsy. Journal of Endourology, 8, 293-299. http://dx.doi.org/10.1089/end.1994.8.293
 
[4]Cordes, J., Lange, B., Jocham, D. and Kausch, I. (2011) Destruction of Stone Extraction Basket during an in Vitro Lithotripsy—A Comparison of Four Lithotripters. Journal of Endourology, 25, 1-4.
http://dx.doi.org/10.1089/end.2011.0019                                                                             eww150108lx
 
[5]Molina, W.R., Silva, I.N., Donalisio da Silva, R., Gustafson, D., Sehrt, D. and Kim, F.J. (2014) Influence of Saline on Temperature Profile of Laser Lithotripsy Activation. Journal of Endourology, 26. (Epub Ahead of Print)
标签：

评论

发表评论

此博客中的热门博文

A Comparison of Methods Used to Determine the Oleic/Linoleic Acid Ratio in Cultivated Peanut (Arachis hypogaea L.)

Cultivated peanut ( Arachis hypogaea L.) is an important oil and food crop. It is also a cheap source of protein, a good source of essential vitamins and minerals, and a component of many food products. The fatty acid composition of peanuts has become increasingly important with the realization that oleic acid content significantly affects the development of rancidity. And oil content of peanuts significantly affects flavor and shelf-life. Early generation screening of breeding lines for high oleic acid content greatly increases the efficiency of developing new peanut varieties. The objective of this study was to compare the accuracy of methods used to classify individual peanut seed as high oleic or not high oleic. Three hundred and seventy-four (374) seeds, spanning twenty-three (23) genotypes varying in oil composition (i.e. high oleic (H) or normal/not high oleic (NH) inclusive of all four peanut market-types (runner, Spanish, Valencia and Virginia), were individually tested ...
发表评论
阅读全文

Location Optimization of a Coal Power Plant to Balance Costs against Plant’s Emission Exposure

Fuel and its delivery cost comprise the biggest expense in coal power plant operations. Delivery of electricity from generation to consumers requires investment in power lines and transmission grids. Placing a coal power plant or multiple power plants near dense population centers can lower transmission costs. If a coalmine is nearby, transportation costs can also be reduced. However, emissions from coal plants play a key role in worsening health crises in many countries. And coal upon combustion produces CO 2 , SO 2 , NO x , CO, Metallic and Particle Matter (PM10 & PM2.5). The presence of these chemical compounds in the atmosphere in close vicinity to humans, livestock, and agriculture carries detrimental health consequences. The goal of the research was to develop a methodology to minimize the public’s exposure to harmful emissions from coal power plants while maintaining minimal operational costs related to electric distribution losses and coal logistics. The objective was...
发表评论
阅读全文

Evaluation of the Safety and Efficacy of Continuous Use of a Home-Use High-Frequency Facial Treatment Appliance

At present, many home-use beauty devices are available in the market. In particular, many products developed for facial treatment use light, e.g., a flash lamp or a light-emitting diode (LED). In this study, the safety of 4 weeks’ continuous use of NEWA TM , a high-frequency facial treatment appliance, every alternate day at home was verified, and its efficacy was evaluated in Japanese individuals with healthy skin aged 30 years or older who complained of sagging of the facial skin.  Transepidermal water loss (TEWL), melanin levels, erythema levels, sebum secretion levels, skin color changes and wrinkle improvement in the facial skin were measured before the appliance began to be used (study baseline), at 2 and 4 weeks after it had begun to be used, and at 2 weeks after completion of the 4-week treatment period (6 weeks from the study baseline). In addition, data obtained by subjective evaluation by the subjects themselves on a visual analog scale (VAS) were also analyzed. Fur...
发表评论
阅读全文