Kazuki Yokota
Nagoya University
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Publication
Featured researches published by Kazuki Yokota.
BioMed Research International | 2015
Naruhiko Murase; Hiroo Uchida; Yasuyuki Ono; Takahisa Tainaka; Kazuki Yokota; Akihide Tanano; Chiyoe Shirota; Ryo Shirotsuki
Purpose. Kasai portoenterostomy is the standard therapy for biliary atresia (BA). If Kasai is unsuccessful, there is controversy over whether revision of Kasai restores adequate biliary drainage. Although there are several reports of laparoscopic Kasai (Lap-Kasai), none has described laparoscopic revision (Lap-revision). The purposes of this study were to evaluate the feasibility and efficacy of Lap-revision. Methods. 65 patients underwent open Kasai between November 2001 and November 2013, and 12 patients underwent Lap-Kasai between December 2013 to January 2015. The indications for revision included bile flow cessation and recurrent cholangitis. Clinical data were compared between open and laparoscopic revisions of Kasai. Results. Open revision of Kasai was performed in 20 patients after open Kasai, and Lap-revision was performed in 4 patients after Lap-Kasai. Lap-revision was completed without conversion or major complication in any patient. The bilirubin level was normalized by Lap-revision in all four patients, and three of them were alive with their native liver. Open and laparoscopic revisions of Kasai were comparable in terms of the operation time, blood loss, and surgical outcomes. Conclusion. Lap-revision is a feasible and effective method for the treatment of BA and might herald a new era for the treatment of this disease.
Pediatrics International | 2015
Naruhiko Murase; Hiroo Uchida; Kenitiro Kaneko; Yasuyuki Ono; Satoshi Makita; Kazuki Yokota
Anastomotic stricture is the main complication after esophageal atresia (EA) repair. In this study, we assessed the efficacy of long‐term prophylactic H2 blocker treatment in preventing stricture.
Jsls-journal of The Society of Laparoendoscopic Surgeons | 2015
Hizuru Amano; Hiroo Uchida; Hiroshi Kawashima; Kyoichi Deie; Naruhiko Murase; Satoshi Makita; Kazuki Yokota; Yujiro Tanaka
Background and Objectives: For reduced port surgery in pediatric patients, the initial umbilical incision plays an important role in both functional ability and cosmetic impact. Larger umbilical incisions enable better manipulation of forceps, extraction of larger surgical specimens, and easier exteriorization of the intestine for anastomosis. We have pursued an incision of the small pediatric umbilicus that allows for enlargement of the orifice of the abdominal opening with preservation of the natural umbilical profile. This article aims to present a new umbilical incision technique and describe the outcomes. Methods: We devised a new umbilical incision technique for reduced port surgery in pediatric patients. Our incision is made in an inverted Y shape (Benz incision), allowing for access port device insertion. The Benz incision technique was applied between November 2010 and May 2014 and was retrospectively studied. Results: Seventy-five patients underwent Benz incisions. The median age of all patients was 6 years 6 months (range, 26 days to 18 years), and the median body weight was 21.7 kg (range, 3.1–54.3 kg). Benz incisions were applied for various procedures, including reduced port surgery with hepaticojejunostomy for congenital biliary dilatation, portojejunostomy for biliary atresia, Meckel diverticulectomy, tumor resection, varicocelectomy, cholecystectomy, splenectomy, ileus surgery, ileocecal resection, and total colectomy. All patients were successfully treated, without a significant increase in operating time or severe complications. The cosmetic profile of the umbilicus was maintained after surgery. Conclusion: The Benz incision is a feasible, effective, and scarless approach for reduced port surgery in pediatric patients whose umbilical rings are too small for the conventional approach.
Journal of Laparoendoscopic & Advanced Surgical Techniques | 2017
Takahisa Tainaka; Hiroo Uchida; Akihide Tanano; Chiyoe Shirota; Akinari Hinoki; Naruhiko Murase; Kazuki Yokota; Kazuo Oshima; Ryo Shirotsuki; Kosuke Chiba; Hizuru Amano; Hiroshi Kawashima; Yujiro Tanaka
BACKGROUND The treatment of long-gap esophageal atresia remains an issue for pediatric surgeons. Many techniques for treating long-gap esophageal atresia have been proposed, but the optimal method has not been established. The thoracoscopic esophageal elongation technique has recently been developed. We previously reported a case in which two-stage thoracoscopic repair was performed using internal esophageal traction without esophageal tearing, and we retrospectively reviewed the outcomes of this procedure in this study. METHODS Five patients underwent thoracoscopic treatment involving internal esophageal traction for esophageal atresia involving a long gap or vascular ring over a 5-year period. RESULTS Between November 2010 and November 2015, 5 patients were treated with thoracoscopic traction. All of these patients successfully underwent thoracoscopic-delayed primary anastomosis. Conversion to open thoracotomy was not required in any case. The postoperative complications experienced by the patients included minor anastomotic leakage in 2 cases, anastomotic stenosis in 1 case, gastroesophageal reflux (GER) in 4 cases, and a hiatal hernia in 1 case. None of the patients died. CONCLUSIONS Two-stage thoracoscopic repair for esophageal atresia involving a long gap or vascular ring is a safe and feasible procedure; however, we must develop methods for treating minor anastomotic complications and GER due to esophageal traction in future.
Journal of Hepato-biliary-pancreatic Sciences | 2016
Chiyoe Shirota; Hiroo Uchida; Yasuyuki Ono; Naruhiko Murase; Takahisa Tainaka; Kazuki Yokota; Kazuo Oshima; Ryo Shirotsuki; Akinari Hinoki; Hisami Ando
The indications for and efficacy of revision of portoenterostomy (PE) for biliary atresia (BA) needs to be reassessed in an era of liver transplantation. We therefore reviewed the long‐term outcomes following revision of PE.
Pediatric Surgery International | 2018
Kazuki Yokota; Hiroo Uchida; Takahisa Tainaka; Yujiro Tanaka; Chiyoe Shirota; Akinari Hinoki; Takazumi Kato; Wataru Sumida; Kazuo Oshima; Kosuke Chiba; Tetsuya Ishimaru; Hiroshi Kawashima
PurposeThe Soave procedure (SO) is performed most commonly for Hirschsprung disease. SO reduces the risk of injury to the pelvic structures; however, a residual aganglionic muscle cuff could interfere with bowel movement and lead to obstructive enterocolitis. The Swenson procedure is considered ideal in terms of peristalsis. Currently, laparoscopic surgery provides better visualization and facilitates precise dissection, possibly leading to feasible performance of the laparoscopic modified Swenson procedure (SW). We present our operative technique and the efficacy of the SW compared with that of SO.MethodsWe retrospectively reviewed the records of 16 and 27 patients who underwent SW and SO, respectively, between 2012 and 2017.ResultsOperative time, blood loss, length of stay, and frequency of bowel movements showed no significant difference between the two groups. In the SW group, temporary dysuria occurred in one patient, postoperative enterocolitis in two, wound infection in one, and severe perianal excoriation in four, whereas in the SO group, obstructive symptoms occurred in three patients, small-bowel obstruction in one, and severe perianal excoriation in three. The complications and outcomes were comparable between both groups.ConclusionLaparoscopic SW was safe and feasible for the short-term follow-up outcomes.
Journal of Pediatric Surgery | 2018
Ryo Shirotsuki; Hiroo Uchida; Yujiro Tanaka; Chiyoe Shirota; Kazuki Yokota; Naruhiko Murase; Akinari Hinoki; Kazuo Oshima; Kosuke Chiba; Wataru Sumida; Masahiro Hayakawa; Takahisa Tainaka
BACKGROUND Postoperative chylothorax after surgery for esophageal atresia/tracheoesophageal fistula (TEF) is a rare but serious complication, especially in neonates. This study aimed to identify the thoracic duct and ligate chylous leakage sites, using thoracoscopic navigation of an indocyanine-green (ICG)-based near-infrared (NIR) fluorescence imaging system. METHODS From November 2014 to April 2017, thoracoscopic intraoperative ICG-NIR imaging was performed in 10 newborns (11 surgeries) with first TEF operation or with persistent postoperative chylothorax after TEF operation. NIR imaging was performed 1h after an inter-toe injection of ICG. Thoracoscopic ligations against the NIR-detected leakage sites were performed with sutures. RESULTS The thoracic duct or lymphatic leakage was directly visualized in each patient. In 8 surgeries with first thoracoscopic TEF operation, one case had suspected minor chylous leakage without postoperative chylothorax. Another case with no chylous leakage at the first operation resulted in chylothorax at postoperative day 11. In three neonates with postoperative chylothorax, leakage points were detected near the ablation site of the azygos vein during the first operation. These points were properly ligated, and postoperative chylous leakage ceased with no adverse events. CONCLUSIONS Thoracoscopic ICG-NIR imaging encourages the repair of refractory chylothorax and seems reliable. LEVEL OF EVIDENCE IV.
Journal of Minimal Access Surgery | 2017
Kazuo Oshima; Hiroo Uchida; Takahisa Tainaka; Akihide Tanano; Chiyoe Shirota; Kazuki Yokota; Naruhiko Murase; Ryo Shirotsuki; Kosuke Chiba; Akinari Hinoki
A right aortic arch (RAA) is found in 5% of neonates with tracheoesophageal fistulae (TEF) and may be associated with vascular rings. Oesophageal repairs for TEF with an RAA via the right chest often pose surgical difficulties. We report for the first time in the world a successful two-stage repair by left-sided thoracoscope for TEF with an RAA and a vascular ring. We switched from right to left thoracoscopy after finding an RAA. A proximal oesophageal pouch was hemmed into the vascular ring; therefore, we selected a two-stage repair. The TEF was resected and simple internal traction was placed into the oesophagus at the first stage. Detailed examination showed the patent ductus arteriosus (PDA) completing a vascular ring. The subsequent primary oesophago-oesophagostomy and dissection of PDA was performed by left-sided thoracoscope. Therefore, left thoracoscopic repair is safe and feasible for treating TEF with an RAA and a vascular ring.
Journal of Investigative Surgery | 2017
Naruhiko Murase; Takahisa Tainaka; Hiroo Uchida; Akinari Hinoki; Chiyoe Shirota; Kazuki Yokota; Kazuo Oshima; Ryo Shirotsuki; Kosuke Chiba; Yujiro Tanaka
ABSTRACT Purpose: Experimental models of laparoscopic surgery generally use large animals owing to a sufficient abdominal working space. We developed a novel laparoscopic surgery model in rats. We performed intestinal anastomosis to demonstrate the feasibility and reliability of this model. Materials and Methods: We designed a device for rats that expanded the abdominal working space and allowed us to manipulate the intraperitoneal organs by hand under direct vision with pneumoperitoneum. We performed small bowel resection and intestinal anastomosis in rats using this model. To elucidate the effects of pneumoperitoneum and skin incision length, rats were randomly divided into four groups with differing surgical techniques: small incision group, large incision group, small incision + pneumoperitoneum group, and large incision + pneumoperitoneum group. Intraoperative abdominal pressure and postoperative cytokines were measured. Results: One experimenter completed small bowel resection and hand-sewn anastomosis under direct vision without any difficulties or assistance. Carbon dioxide pneumoperitoneum was maintained at 8–10 mmHg during surgery in both pneumoperitoneum groups. Necropsies revealed no evidence of anastomotic leakage at 24 h after surgery. The interleukin-6 and C-reactive protein concentrations were significantly greater in large incision group than in small incision group, but were not significantly different between small incision + pneumoperitoneum group and small incision group. These cytokines concentrations were the greatest in large incision + pneumoperitoneum group. Conclusions: Our laparoscopic surgery model in rats is a simple and reliable experimental model. The length of skin incision might be a more influential determinant of surgical invasiveness than pneumoperitoneum.
Nagoya Journal of Medical Science | 2016
Takahisa Tainaka; Hiroo Uchida; Yujiro Tanaka; Chiyoe Shirota; Kazuki Yokota; Naruhiko Murase; Kazuo Oshima; Ryo Shirotsuki; Kosuke Chiba; Akinari Hinoki
ABSTRACT Thoracoscopic lobectomy has recently become a widely used surgical treatment for congenital cystic lung disease, but significant issues can arise in some cases, such as a limited working space in neonates, a limited view in cases involving large cystic lesions. We reviewed the treatment outcomes of neonates that underwent complete thoracoscopic lobectomy or segmentectomy and evaluated the operative difficulties. From January 2008 to October 2015, 38 patients under the age of 1 year underwent complete thoracoscopic lobectomy or segmentectomy for cystic lung disease at our institution. We compared the intra- and postoperative data of the neonate group (N group) with those of the infant group (I group). Fourteen and 24 patients underwent thoracoscopic lobectomy or segmentectomy in the N group and I group, respectively. The operative time and amount of intraoperative blood loss did not differ significantly between the two groups (p=0.694 and p=0.878, respectively), but the duration of the postoperative hospitalization period was significantly longer (p<0.01) in the N group. The frequencies of postoperative complications did not differ significantly between the two groups. The operative time of thoracoscopic lobectomy was significantly longer in cases involving incomplete lobar fissures than in those involving normal lobar fissures. Surgical outcomes of complete thoracoscopic lobectomy for neonatal cases are almost equivalent compared with infantile cases, and thoracoscopic lobectomy takes longer in cases involving incomplete lobar fissures.