Naotaka Nakama

IIzuka Hospital, Иидзука, Fukuoka, Japan

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Publications (7)22.07 Total impact

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    ABSTRACT: Colonic diverticular bleeding can stop spontaneously or be stopped by endoscopic hemostasis. We analyzed the clinical and colonoscopic features of patients with colonic diverticular bleeding to establish the predictive factors for rebleeding. A total of 111 patients (median age, 72 years) with colonic diverticular bleeding in Aso Iizuka Hospital between April 2007 and July 2010 were enrolled. Age, sex, body mass index (BMI), comorbidity, medication, location of bleeding, colonoscopic findings and hemostatic methods were analyzed retrospectively from the hospital records. The most common sites of bleeding were the ascending (39.6%) and sigmoid (29.7%) colon. Overt rebleeding occurred in 30 patients (27.0%). Spontaneous hemostasis was seen in 81 patients (73.0%), and endoscopic hemostatic treatment was performed in 30 patients. The BMI in the patients with colonic diverticular rebleeding was significantly higher than in patients without rebleeding. Colonoscopic findings of actively bleeding or nonbleeding visible vessels in the responsible diverticula were more frequent in the group with rebleeding. A higher BMI and colonoscopic findings of actively bleeding or nonbleeding visible vessels can be used as predictive factors for colonic diverticular rebleeding. Patients with such findings should be carefully followed up after hemostasis of the initial colonic diverticular bleeding.
    Gut and liver 07/2012; 6(3):334-8. · 1.31 Impact Factor
  • Endoscopy 05/2012; 44 Suppl 2:E162. · 5.74 Impact Factor
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    ABSTRACT: Endoscopic submucosal dissection (ESD) with a knife is a technically demanding procedure associated with a high complication rate. The shortcomings of this method are the deficiencies of fixing the knife to the target lesion, and of compressing it. These shortcomings can lead to major complications such as perforation and bleeding. To reduce the risk of complications related to ESD, we developed a new grasping type scissors forceps (Clutch Cutter®, Fujifilm, Japan) which can grasp and incise the targeted tissue using an electrosurgical current. Esophagogastroduodenoscopy on a 59-year-old Japanese man revealed a 16mm esophageal submucosal nodule with central depression. Endoscopic ultrasonography demonstrated a hypoechoic solid tumor limited to the submucosa without lymph node involvement. The histologic diagnosis of the specimen obtained by biopsy was granular cell tumor. It was safely and accurately resected without unexpected incision by ESD using the CC. No delayed hemorrhage or perforation occurred. Histological examination confirmed that the granular cell tumor was completely excised with negative resection margin.We report herein a case of esophageal granular cell tumor successfully treated by an ESD technique using the CC.
    World journal of gastrointestinal endoscopy. 01/2012; 4(1):17-21.
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    ABSTRACT: Endoscopic submucosal dissection (ESD) is accepted as minimally invasive therapy for early stage digestive tract tumors. It has allowed the achievement of histologically curative en-bloc resection of early stage digestive tract tumors regardless of size, including the resection of previously non-resectable tumors. Although numerous electrosurgical knives have been developed for ESD, technical difficulties and high complication rates (bleeding and perforation) have limited their use worldwide. Furthermore, conventional ESD usually needs several devices for each session. We developed the Clutch Cutter® (CC), which can grasp and incise the targeted tissue using electrosurgical current, to resolve such ESD-related problems. The ESD procedure using the CC is as follows: after marking using the CC and the injection of a solution into the submucosa, the lesion is separated from the surrounding normal mucosa by complete incision around the lesion using the CC. A piece of submucosal tissue is grasped and cut with the CC using electrosurgical current to achieve submucosal exfoliation. Intraoperative bleeding is also treated by the CC. Reported clinical studies showed that ESD using the CC is a safe, simple, easy-to-learn, technically efficient (en-bloc resection rate 100%), and a single-device method for the dissection of early stage digestive tract tumors. This new approach is promising to become the worldwide method of choice for early stage digestive tract tumors because it is technically simple and safe to perform.
    Digestion 01/2012; 85(2):80-4. · 1.94 Impact Factor
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    ABSTRACT: To reduce the risk of complications related to endoscopic submucosal dissection (ESD) using knives, we developed a new grasping-type scissors forceps (GSF) that can grasp and incise the target tissue using electrosurgical current. The aim of the present study was to evaluate the efficacy and safety of ESD using GSF for the removal of early gastric cancers and adenomas. ESD using GSF was carried out on 35 consecutive patients with early gastric cancers or adenomas who had preoperative EUS diagnoses of mucosal tumor without lymph node involvement. Therapeutic efficacy and safety were assessed. All lesions were treated easily and safely without unexpected incision. The mean size of epithelial tumors and resected specimens was 15.6mm and 32.7mm, respectively. Curative en-bloc resection rates according to tumor size and location were 96% (26/27) in tumors ≤20mm, 100% (8/8) in tumors >20mm, 100% (18/18) of tumors in the lower portion, 100% (8/8) of tumors in the middle portion, 89% (8/9) of tumors in the upper portion, and 97% (34/35) overall. The mean operating time according to tumor size and location was 93.4min in tumors ≤20mm, 140min in tumors >20mm, 77.6min for tumors in the lower portion, 113.4min for tumors in the middle portion, 148.6min for tumors in the upper portion, and 104.1min overall. No intraoperative complication occurred, and postoperative bleeding was seen in 3% (1/35). ESD using GSF allows simple and safe en-bloc resection of early gastric cancer or adenoma irrespective of tumor size and location.
    Digestive Endoscopy 01/2011; 23(1):24-9. · 1.61 Impact Factor
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    ABSTRACT: To reduce the risk of complications related to endoscopic submucosal dissection (ESD), we developed a new grasping-type scissors forceps (GSF), which can grasp and incise the targeted tissue using an electrosurgical current. We prospectively evaluated the efficacy and safety of ESD using GSF for the removal of colorectal tumors in 10 consecutive patients. After the submucosa had been injected with a solution, the lesion was separated from the surrounding normal mucosa by complete incision around the lesion using the GSF. A piece of submucosal tissue was grasped and cut with the GSF using an electrosurgical current to achieve submucosal excision. All lesions were treated easily and safely with no unexpected incisions. No delayed hemorrhage or perforation occurred. En bloc resection was obtained in all cases. The tumor-free lateral/basal margins were obtained in eight out of 10 patients. ESD using GSF appears to be an easy, safe, and technically efficient method for resecting early colorectal tumors.
    Endoscopy 03/2010; 42(5):419-22. · 5.74 Impact Factor
  • Endoscopy 01/2010; 42 Suppl 2:E199-200. · 5.74 Impact Factor