Steger A C, Shorvon P, Walmsley K, Chisholm R, Bown S G, Lees W R
National Medical Laser Centre, University College and Middlesex Hospital.
Clin Radiol. 1992 Aug;46(2):88-93. doi: 10.1016/s0009-9260(05)80309-5.
Low power interstitial laser hyperthermia (ILH) is a reliable means of producing in situ thermal necrosis. Ultrasonic studies have been carried out of the changes that occur in canine liver during ILH performed at laparotomy. With a single fibre delivering Nd-YAG laser at 1-1.5 W for 670 s an hyperechoic region developed at the fibre tip measuring 5-6 mm in diameter; around this developed an area of hypoechoic change (up to 500s) giving a total area of changed echogenicity of 14-16 mm. With a multiple fibre system using 4 laser fibres simultaneously the sonographic changes were a summation of the changes seen with a single fibre, the hypoechoic areas overlapping. With this four fibre system the creation of large (3.5 x 2.8 cm) areas of thermal necrosis was possible. There was good correlation between the sonographic and pathological measurements of the region of thermal change. The sonographic studies showed the extension and overlap of regions of thermal necrosis and allowed visualization and accurate measurement of the area undergoing change. The same combined technique has been successfully applied in a small number of clinical cases and may be of use in the treatment of tumours in solid organs.
低功率间质激光热疗（ILH）是一种可靠的原位产生热坏死的方法。已对开腹进行ILH时犬肝脏中发生的变化进行了超声研究。使用单根光纤以1-1.5W的功率输送Nd-YAG激光670秒，光纤尖端会形成一个直径为5-6mm的高回声区域；在此区域周围会出现一个低回声变化区域（长达500秒），使回声性改变的总面积达到14-16mm。使用多光纤系统同时使用4根激光光纤时，超声变化是单根光纤所见变化的总和，低回声区域相互重叠。使用这种四光纤系统可以形成大的（3.5×2.8cm）热坏死区域。热变化区域的超声测量与病理测量之间具有良好的相关性。超声研究显示了热坏死区域的扩展和重叠，并能够可视化和准确测量发生变化的区域。同样的联合技术已成功应用于少数临床病例，可能对实体器官肿瘤的治疗有用。
