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Dive into the research topics where Takamasa Maruyama is active.

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Featured researches published by Takamasa Maruyama.


Diseases of The Colon & Rectum | 1999

Enlargement of colonic pouch after proctectomy and colonanal anastomosis: Potential cause for evacuation difficulty

Jin-ichi Hida; Masayuki Yasutomi; Takamasa Maruyama; Tadao Tokoro; Tsukasa Wakano; Toshihiro Uchida

PURPOSE: Although the functional outcome after low anterior resection for rectal cancer using colonic J-pouch reconstruction is superior to that using conventional straight reconstruction, the one drawback of colonic J-pouch reconstruction is difficulty with evacuation. Recently it has been suggested that construction of a larger colonic J-pouch causes the evacuation difficulty. The purpose of this study was to elucidate the cause of evacuation difficulty with colonic J-pouch reconstruction. METHODS: We compared pouchography of 26 patients with 10-cm colonic J-pouch reconstructions (10-J group) and 27 patients with 5-cm colonic J-pouch reconstructions (5-J group) at three months, one year, and two years after surgery. Functional assessments were performed one year postoperatively. Clinical function was evaluated using a questionnaire. Evacuation function was evaluated by the balloon expulsion and saline evacuation tests. RESULTS: The greatest width of the pouch in the 10-J group in the anteroposterior view was significantly greater than that in the 5-J group at all three measurement times (3 months, 4.9vs. 4 cm;P=0.0011; 1 year, 9vs. 5.6 cm;P<0.0001; 2 years, 9.2vs. 5.8 cm;P<0.0001). The value in the 10-J group at one year after surgery was 1.9 times that at three postoperative months; in the 5-J group this ratio was 1.4. There was a significant difference between these ratios (P<0.0001). No significant difference existed between the values at two years and one year after surgery in either the 10-J or the 5-J group. An evacuation difficulty was significantly more common in the 10-J group than the 5-J group. Evacuation function in the 10-J group was significantly inferior to that in the 5-J group. CONCLUSIONS: The evacuation difficulty observed in patients with larger colonic J-pouch reconstructions is associated with excessive distention of the pouch occurring within one year of surgery.PURPOSE Although the functional outcome after low anterior resection for rectal cancer using colonic J-pouch reconstruction is superior to that using conventional straight reconstruction, the one drawback of colonic J-pouch reconstruction is difficulty with evacuation. Recently it has been suggested that construction of a larger colonic J-pouch causes the evacuation difficulty. The purpose of this study was to elucidate the cause of evacuation difficulty with colonic J-pouch reconstruction. METHODS We compared pouchography of 26 patients with 10-cm colonic J-pouch reconstructions (10-J group) and 27 patients with 5-cm colonic J-pouch reconstructions (5-J group) at three months, one year, and two years after surgery. Functional assessments were performed one year postoperatively. Clinical function was evaluated using a questionnaire. Evacuation function was evaluated by the balloon expulsion and saline evacuation tests. RESULTS The greatest width of the pouch in the 10-J group in the anteroposterior view was significantly greater than that in the 5-J group at all three measurement times (3 months, 4.9 vs. 4 cm; P = 0.0011; 1 year, 9 vs. 5.6 cm; P < 0.0001; 2 years, 9.2 vs. 5.8 cm; P < 0.0001). The value in the 10-J group at one year after surgery was 1.9 times that at three postoperative months; in the 5-J group this ratio was 1.4. There was a significant difference between these ratios (P < 0.0001). No significant difference existed between the values at two years and one year after surgery in either the 10-J or the 5-J group. An evacuation difficulty was significantly more common in the 10-J group than the 5-J group. Evacuation function in the 10-J group was significantly inferior to that in the 5-J group. CONCLUSIONS The evacuation difficulty observed in patients with larger colonic J-pouch reconstructions is associated with excessive distention of the pouch occurring within one year of surgery.


Diseases of The Colon & Rectum | 1998

Results from pelvic exenteration for locally advanced colorectal cancer with lymph node metastases

Jin-ichi Hida; Masayuki Yasutomi; Takamasa Maruyama; Akihiro Nakajima; Toshihiro Uchida; Tsukasa Wakano; Tadao Tokoro; Kiyoshige Fujimoto

PURPOSE: We examined the survival benefit of pelvic exenteration for locally advanced colorectal cancer with lymph node metastases, because this issue remains controversial. METHODS: Medical records of 50 patients who underwent curative pelvic exenteration for colorectal cancer were reviewed retrospectively. Nodal metastases were examined by the clearing method in 29 patients and by the conventional manual method in 21 patients. RESULTS: Invasion to contiguous pelvic organs was present in 40 patients (80 percent) and absent in 10 patients (20 percent). Node metastases were present in 33 patients (66 percent). Operative morbidity and mortality rates were 22 percent (11 patients) and 6 percent (3 patients), respectively. Respective five-year survival rates were 60 and 80 percent in the groups with and without organ invasion (no significant difference). Five-year survival rates in patients with nodal metastases was 54.6 percent but was significantly higher, 82.4 percent, in patients without nodal metastases. Five-year survival in 28 patients with both organ invasion and nodal metastases was 53.6 percent. CONCLUSIONS: Long-term survival was afforded by pelvic exenteration for locally advanced colorectal cancer with nodal metastases.


Archive | 1998

Indications for colonic J-pouch reconstruction after anterior resection for rectal cancer

Jin-ichi Hida; Masayuki Yasutomi; Takamasa Maruyama; Kiyoshige Fujimoto; Akihiro Nakajima; Toshihiro Uchida; Tsukasa Wakano; Tadao Tokoro; Ryuichi Kubo; Katsuhisa Shindo

PURPOSE: Functional outcome after anterior resection for rectal cancer is improved by colonic J-pouch reconstruction compared with straight anastomosis. The indications for colonic J-pouch reconstruction have yet to be determined. Therefore, we attempted to determine the level at which J-pouch reconstruction provides an advantage over straight anastomosis. METHODS: A total of 48 patients who underwent 5-cm colonic J-pouch reconstruction (J-pouch group) and 80 patients who underwent straight anastomosis (straight group) underwent functional assessment one year postoperatively. RESULTS: The functional outcome in the J-pouch group was significantly better than that in the straight group when the distance of the anastomosis from the anal verge was less than 8 cm. The difference was particularly obvious when the level of the anastomosis was below 4 cm. However, functional outcome in the straight group when the anastomosis was between 9 and 12 cm from the anal verge was also satisfactory and did not differ from that in the J-pouch group when the anastomosis was between 5 and 8 cm from the anal verge. CONCLUSIONS: Colonic J-pouch reconstruction is indicated when the distance of anastomosis from the anal verge is less than 8 cm, and it is essential when the distance is less than 4 cm.


Cancer | 1997

The extent of lymph node dissection for colon carcinoma

Jin-ichi Hida; Masayuki Yasutomi; Takamasa Maruyama; Kiyoshige Fujimoto; Toshihiro Uchida; Kiyotaka Okuno

The surgeon is no longer able to palpate the mesocolon for lymph node metastases during laparoscopic colectomy. The extent of lymph node dissection should be determined beforehand for cancer control.


Archive | 1998

Indication for using high ligation of the inferior mesenteric artery in rectal cancer surgery

Jin-ichi Hida; Masayuki Yasutomi; Takamasa Maruyama; Kiyoshige Fujimoto; Akihiro Nakajima; Toshihiro Uchida; Tsukasa Wakano; Tadao Tokoro; Ryuichi Kubo; Katsuhisa Shindo

PURPOSE: In surgery for rectal cancer, it is unclear whether the inferior mesenteric artery should be ligated at a high or low position. The study contained herein was undertaken to clarify the indications for high ligation of the inferior mesenteric artery. METHODS: Subjects included 198 patients with rectal cancer who underwent resection with high ligation of the inferior mesenteric artery. Nodal metastases were examined by the clearing method. RESULTS: The incidence of metastases to the lymph nodes surrounding the origin of the inferior mesenteric artery (root nodes) was 8.6 percent. Inferior mesenteric artery root nodal metastases occurred more frequently with pT3 and pT4 cancer. The five-year survival rate in patients with inferior mesenteric artery root nodal metastases was 38.5 percent; this rate was significantly lower than in those without inferior mesenteric artery root nodal metastases (73.4 percent). CONCLUSIONS: Although the five-year survival rate in patients with inferior mesenteric artery root nodal metastases was lower than in those without metastases, inferior mesenteric artery root nodal dissection should be performed after high ligation of the inferior mesenteric artery for patients with pT3 and pT4 cancers.


Archive | 1999

Horizontal inclination of the longitudinal axis of the colonic J-pouch

Jin-ichi Hida; Masayuki Yasutomi; Takamasa Maruyama; Tadao Tokoro; Toshihiro Uchida; Tsukasa Wakano; Ryuichi Kubo

PURPOSE: Functional outcome after low anterior resection for rectal cancer is improved by the construction of a colonic J-pouch. One disadvantage of this type of reconstruction is evacuation difficulty, which has been associated with large pouches. The purpose of this study was to elucidate the causes of evacuation difficulty in large pouches using pouchography. METHODS: The angle between the longitudinal axis of the pouch and the horizontal line (pouch-horizontal angle) on lateral pouchography was determined in 26 patients with 10-cm J-pouch reconstructions (10-J group) and 27 patients with 5-cm J-pouch reconstructions (5-J group). Measurement were made at three months, one year, and two years after surgery. Clinical function was evaluated using a questionnaire one year postoperatively. RESULTS: The pouch-horizontal angle in the 10-J group was significantly smaller than that in the 5-J group at all three time points. In both groups the pouch-horizontal angle at one year was significantly smaller than that at three months. There were no significant differences between the pouch-horizontal angles at one and two years. An evacuation difficulty was significantly more common in the 10-J group than the 5-J group. CONCLUSIONS: The evacuation difficulty observed in patients with large colonic J-pouch reconstructions may be attributed to the development of a horizontal inclination within one year of surgery.


Surgery Today | 1999

Detection of a rectocele-like prolapse in the colonic J-pouch using pouchography: cause or effect of evacuation difficulties?

Jin-ichi Hida; Masayuki Yasutomi; Takamasa Maruyama; Takehito Yoshifuji; Tadao Tokoro; Tsukasa Wakano; Toshihiro Uchida; Kazuki Ueda

The functional outcome after a low anterior resection for rectal cancer is improved by a colonic J-pouch reconstruction. One functional problem with J-pouches is difficulty in evacuation, which is more common with large reconstructions. Since rectoceles are common findings on defecography in patients with evacuation difficulties, we proposed that a rectocele-like prolapse may be thus found in patients with large J-pouches. Pouchography was used to identifya rectocele-like prolapse (RP) in 26 patients with a 10-cm J-pouch (10-J group) and 27 patients with a 5-cm J-pouch (5-J group). Pouchography was performed at 3 months, 1 year, and 2 years after surgery. Functional assessments were performed 1 year postoperatively. Clinical function was evaluated using a questionnaire. The evacuation function was evaluated by the balloon expulsion and saline evacuation test. No patients had an RP at 3 months or 1 year after surgery. An RP was significantly more common in the 10-J group than in the 5-J group at 2 years after surgery (P=0.0374). An evacuation difficulty was significantly more common in the 10-J group than in the 5-J group. The evacuation function in the 10-J group was also significantly inferior to that in the 5-J group. An RP appearing 2 years after surgery is more common in patients with evacuation difficulties and large colonic J-pouch reconstructions.


Surgery Today | 1999

High ligation of the inferior mesenteric artery with hypogastric nerve preservation in rectal cancer surgery

Jin-ichi Hida; Masayuki Yasutomi; Takamasa Maruyama; Toshihiro Uchida; Akihiro Nakajima; Tsukasa Wakano; Tadao Tokoro; Ryuichi Kubo

We describe herein a technique of performing upward node dissection following high ligation of the inferior mesenteric artery for patients with T3 and T4 rectal carcinomas. The course of the hypogastric nerve is confirmed macroscopically during the procedure to ensure its preservation. This technique offers both increased radicality and the prevention of ejaculatory dysfunction.


Surgery Today | 1997

Functional Outcome After Low Anterior Resection for Rectal Cancer Using the Colonic J-Pouch

Jin-ichi Hida; Masayuki Yasutomi; Kiyoshige Fujimoto; Takamasa Maruyama; Toshihiro Uchida; Kenzo Koh; Kiyotaka Okuno; Katsuhisa Shindo

The functional outcome after low anterior resection (LAR) using the colonic J-pouch was compared with that after LAR using straight anastomosis. Colonic J-pouch construction was performed in 58 patients who underwent resection of tumors located 5–10 cm from the anal verge (J-pouch group). Functional assessment was performed 1 year postoperatively. Clinical function was evaluated using a scoring system, while physiologic sphincter and reservoir function were evaluated by anorectal manometry. The historical control group consisted of 20 patients who underwent LAR with straight anastomoses (straight group). The functional score of the J-pouch group was significantly better than that of the straight group. Although sphincter function was similar in the two groups, reservoir function was significantly better in the J-pouch group than in the straight group. These results demonstrated that the functional outcome following LAR for rectal cancer is improved by the colonic J-pouch construction.


Surgery Today | 1999

COLOANAL ANASTOMOSIS USING A CIRCULAR STAPLING DEVICE FOLLOWING PERINEAL RECTOSIGMOIDECTOMY FOR RECTAL PROLAPSE

Jin-ichi Hida; Masayuki Yasutomi; Takamasa Maruyama; Akihiro Nakajima; Toshihiro Uchida; Tsukasa Wakano; Tadao Tokoro; Ryuichi Kubo; Hiroya Umemura; Katsuhisa Shindo

Perineal rectosigmodectomy with a hand-sewn anastomosis is thought to be the most appropriate procedure for elderly patients deemed unfit to tolerate a major abdominal operation. However, the use of a circular stapling device to perform the coloanal anastomosis following rectosigmoidectomy shortens the operative time and provides a more secure anastomosis than the traditional hand-sewn technique.

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