We have performed hepatectomy using microwave tissue coagulator which we have developed in about 122 patients with liver cancer associated with cirrhosis. Merit of this high hemostatic performance has been put to use from the first and operations with this have been considered to be those which hardly require transfusion during operation. We introduce you the keys and points to be regarded of recent operative technique. Points in operation can be summarized as follows: 1. Portal blocking is not made, 2. Cholecystectomy is made and a catheter is placed in the cystic duct, 3. The line for incision is determined previously by ultrasonography, 4. Coagulation is made mimutely, strongly and in no hurry (80W. 45s), 5. A line for incision is determined to leave coagulation zone which extends from the electrode impaling site to 10mm thereof sufficiently on the side of the remaining liver. 6. Coagulation in the neighborhood of large vessels is avoided, 7. Even though cutting suture occurred at the ligature of small vessel systems, Z-type ligature is applied afterward, 8. When the resection is finished the absence of stump bleeding is confirmed and then indigocamine is infused from a tube which is placed previously and biliary leakage test is made without fail, 9. Omentopexy is made without fail to remove a dead space between the subdiaphragmatic surface and liver. 10. The drain is removed as early as possible to prevent retrograde infection.

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We devised double needle for microwave tissue coagulator in order to shorten the operative time and enlarge the coagulated area in liver resection. And thermal and histological changes of liver were estimated for using it as compared of single needle. It resulted that more than 100 Watt made an effective coagulation and enlarged its area. To prevent heat damage to the rest of liver it will be necessary that double needle should be inserted closer to the liver focus than in the single needle and/or during coagulation liver should be cooled in its clinical use.

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We evaluated the change of the resecting margin in the liver after hepatectomy using Microwave Tissue Coagulator by. Computed Tomography (CT).
CT scan revealed sharply demarcated low density area along with the resecting margin in the liver. The “volume” of the low densiy area was calculated by multiplying the low density area by the width of the slice of CT scan and adding them in all slice.
In this study the following results were found; 1) The “low density volume” decreased postoperatively and the “volume” at D1 postoperative day was estimated to reduce by half at 4.5×D₁ postoperative day. 2) As for the relationship between the “low density volume (V)” at 1 month after operation and the size of resected specimen, there was a correlation V=7.54R+29.2 (cm³)(coefficient of correlation 0.92, P<0.05), when R was the mean of the long and short diameter of the oval shaped resecting line which we mapped out on the surface of the liver.
The result of this study may be useful to estimate the damaged volume near the resecting margin in the liver using Microwave Tissue Coagulator.

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For the treatment of malignat gliomas, a hyperthermia microwave probe with a water-cooling system has been developed. This system can be utilized Iseki's CT-guided stereotactic frame and has the advantage of possibility of produce useful tissue temperature of up to 42.5°C within localized thermal field of 3cm in diameter without thermal toxity to critical normal brain tissue
The new water-cooling system consists of the outer catheter with circulating water of 0-1°C, the cooling container Model 93-520 and an infusion pump. Even if the microwave antenna to be operated at 30W power, the temperature surrounding the microwave pobe was limited less 35°C that induced no definite thermal damage to normal brain tissue. The tissue temperatue was measured in three patients with malignant glioma at three points 5mm, 10mm, and 15mm from the tip of the antenna. The antenna produced useful heating field of 43°C within 3cm in diameter 7-9 minites after starting hyperthermia treatment.
Combination of the microwave probe with the water-cooling system and CT-EHO-guided stereotactic appratus could be effective in the application of microwave brain hyperthermia for malignant deep-seated brain tumors that are impossible to perform conventional surgical treatnent.

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The superior coagulation capacity of the application of microwave energy in tissue has been established in hapatectomy and endoscopic therapy and the pathological features of internal hemorrhoids raise high expectations for the therapeutic efficacy of microwave use. We have studied the use of the microwave coagulation method for outpatients with internal hemorrhoids and we hereby our results.
We performed microwave coagulation therapy in 13 cases of internal hemorrhoids. There were nine cases (39%) of Stage II hemorrhoids according to the Goligher Classification System and four cases of Stage III (31%). The efficacy was broken up into three evaluations by clinical score: Extremely effective, Effectiva, and Ineffective. The ratio of cases that were effective or better were 77.8% for Stage II cases and 75.0% for Stage III cases. It was felt that this method was very satisfactory for use in treatments.
In addition, we applied microwave coagulation immediately before ligature and excision of hemorrhoids. The histological study, revealed that varicas of hemorrhoids were coagulated and swelled in the vessels wall and the interstial tissus.

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