Ryutaro Imai
Tokyo Medical University
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Publication
Featured researches published by Ryutaro Imai.
Annals of Plastic Surgery | 2008
Ryutaro Imai; Hajime Matsumura; Koji Tanaka; Ryuji Uchida; Katsueki Watanabe
Background:Multidetector-row computed tomography (MDCT) has been recently introduced to detect the perforator vessels. The aim of this study is to compare the MDCT with Doppler ultrasound and assess the usefulness of the MDCT for the preoperative planning. Methods:Five healthy adult men were first assessed for the perforators and marked with rubber using the Doppler ultrasound before MDCT was performed. Using these images, the number and the location of the perforator were evaluated. Results:We could detect 83 perforators on five cases, while could detect 35 perforators by the Doppler ultrasound. We measured the distance from the fascia perforating points to rubber markings points. It ranged from 0 to 22.47 mm (7.62 mm on average). Conclusion:MDCT angiography is useful for preoperative planning of deep inferior epigastric artery perforator flap at the point of more accurate anatomical findings and clear images of perforator vessels compared to the findings using Doppler ultrasound.
International Wound Journal | 2014
Hajime Matsumura; Ryutaro Imai; Niyaz Ahmatjan; Yukiko Ida; Masahide Gondo; Dai Shibata; Katsueki Wanatabe
In recent years, adhesive wound dressings have been increasingly applied postoperatively because of their ease of use as they can be kept in place without having to cut and apply surgical tapes and they can cover a wound securely. However, if a wound dressing strongly adheres to the wound, a large amount of stratum corneum is removed from the newly formed epithelium or healthy periwound skin. Various types of adhesives are used on adhesive wound dressings and the extent of skin damage depends on how much an adhesive sticks to the wound or skin surface. We quantitatively determined and compared the amount of stratum corneum removed by eight different wound dressings including polyurethane foam using acrylic adhesive, silicone‐based adhesive dressing, composite hydrocolloid and self‐adhesive polyurethane foam in healthy volunteers. The results showed that wound dressings with silicone adhesive and self‐adhesive polyurethane foam removed less stratum corneum, whereas composite hydrocolloid and polyurethane foam using acrylic adhesive removed more stratum corneum.
Burns | 2013
Hajime Matsumura; Masahide Gondo; Ryutaro Imai; Dai Shibata; Katsueki Watanabe
The application of cultured epidermal autograft (CEA) over bilayer artificial dermis theoretically should minimize surgical stress and donor site morbidity in severe burn patients. However, CEA over regenerated dermis is very fragile and easily detaches soon after application, because the very weak attachment. We performed chronological histological studies of the wounds of a 29 year-old patient, which was reconstructed using CEA (JACE(®)) and bilayer artificial dermis (Integra™). These studies included immunohistochemistry of anti-collagen (types III, IV, and VII) and anti-laminin, in addition to H&E and EVG staining. Reconstructed epidermis and dermis showed almost normal histological appearance with time, but formation of basement membrane proteins was delayed. Absent or immature basement membrane protein in the early phase after the CEA application was considered to be an important problem. In the late phase after the CEA application over the bilayer artificial dermis, the reconstructed skin was very durable and demonstrated no sign of skin stripping (although there was still a lack of basement membrane proteins).
Asia Pacific Journal of Clinical Nutrition | 2015
Kanae Nishizaki; Hitoshi Ikegami; Yukio Tanaka; Ryutaro Imai; Hajime Matsumura
OBJECTIVES Total knee arthroplasty (TKA) performed in knee osteoarthritis patients is reported to be immediately followed by a decrease in quadriceps muscle strength. We investigated the effects of supplementation with a combination β-hydroxy-β-methyl butyrate, L-arginine, and L-glutamine (HMB/Arg/Gln) on the postoperative recovery of quadriceps muscle strength in patients after TKA. METHODS Study subjects were 23 patients (12 women; mean age: 70.5) who underwent TKA. The patients were randomly allocated into the control group or the group that consumed HMB/Arg/Gln supplementation (HMB/Arg/Gln group). HMB/Arg/Gln supplementation or control food were consumed for 5 days before the surgery and for 28 days after the surgery, and maximal quadriceps strength was measured at 7 days before the surgery, and at 14, 28 and 42 days after the surgery. During the study, total energy expenditure was measured using a lifestyle recording device. The two groups followed the rehabilitation in the same way. RESULTS The maximal quadriceps strength was 1.1±0.62 Nm/Kg before surgery and 0.7±0.9 Nm/Kg after surgery 14 days in the control group (p=0.02), and 1.1±0.3 Nm/Kg before surgery and 0.9±0.4 Nm/Kg after surgery 14 days in the HMB/Arg/Gln group. Although the control group experienced a significant loss of muscle strength after the surgery, the HMB/Arg/Gln group did not. There was no significant difference in total energy expenditure between the two groups. CONCLUSIONS Consuming HMB/Arg/Gln supplementation may suppress the loss of muscle strength after TKA. Intervention with exercise and nutrition appears to enable patients to maintain their quadriceps strength.
Scandinavian Journal of Plastic and Reconstructive Surgery and Hand Surgery | 2009
Ryuji Uchida; Hajime Matsumura; Ryutaro Imai; Koji Tanaka; Katsueki Watanabe
Our aim was to explore the anatomical features of the cutaneous perforators from the ulnar palmar digital artery of the little finger and to establish the anatomical basis of the ulnar palmar digital artery perforator flap for reconstruction of the ulnar aspect of the palm and fingers. We found that at least one perforator is present between the metacarpophalangeal (MCP) joint and 9 mm proximal to the MCP joint. This finding establishes the anatomical basis of the distal base ulnar palmar digital artery perforator flap for reconstruction of the ulnar aspect of the palm and fingers.
International Wound Journal | 2016
Yukiko Ida; Hajime Matsumura; Masami Onishi; Sayaka Ono; Ryutaro Imai; Katsueki Watanabe
It has been reported that negative pressure wound therapy (NPWT) is effective in the treatment of contaminated wounds. We hypothesised that systemically administered antibiotics migrate to wound site effectively by NPWT, which provides the antibacterial effect. We measured and compared the concentrations of vancomycin in the exudate and blood serum. Eight patients with skin ulcers or skin defect wounds who were treated with NPWT and were administered an intravenous drip of vancomycin were enrolled in this study. The wound surfaces were muscle, muscle fascia or adipose tissue. We administered vancomycin intravenously to NPWT patients (1–3 g/day). The exudate was obtained using 500 ml V.A.C. ATS® canisters without gel. Three days later, the concentrations of vancomycin were measured. The mean concentration of vancomycin in the exudate from NPWT was 67% of the serum vancomycin concentration. We found that concentrations of vancomycin in NPWT exudates are higher than the previously reported concentrations in soft tissue without NPWT. The proactive use of NPWT might be considered in cases of suspected wound contamination when a systemic antibiotic is administered.
International Wound Journal | 2013
Hajime Matsumura; Niyaz Ahmatjan; Yukiko Ida; Ryutaro Imai; Katsueki Wanatabe
The removal of adhesive wound dressings from the wound surface involves a risk of damaging the intact stratum corneum and regenerating epithelium. Pain associated with the removal of wound dressings is a major issue for patients and medical personnel. Recently, wound dressings coated with a silicone adhesive have been developed to reduce such skin damage and pain on removal and they have received good evaluation in various clinical settings. However, there is neither a standard method to quantify whether or not the integrity of the stratum corneum and regenerating epithelium is retained or if both structures are damaged by the removal of wound dressings, nor are there standardised values with which to assess skin damage. We applied six different types of adhesive wound dressing on plain copy paper printed with black ink by a laser printer, removed the dressings, examined the adhesive‐coated surface of the wound dressings using a high‐power videoscope, and examined the stripped areas. Wound dressings coated with a silicone adhesive showed significantly less detachment of the stratum corneum and regenerating epithelium, followed by those coated with polyurethane, hydrocolloid, and acrylic adhesives. The assessment method utilised in this study revealed distinct differences between wound dressing types, but less variation in the evaluation outcome of each type. This assessment method may be useful for the evaluation of adhesive wound dressings, particularly during product development. However, further studies will be needed to examine the effectiveness of this assessment method in the clinical setting because the adherent properties of polyurethane and hydrocolloid adhesives may be altered by the absorption of water from the skin.
Antimicrobial Agents and Chemotherapy | 2015
Itaru Nakamura; Natsuki Sakamoto; Yukiko Ida; Ryutaro Imai; Kotaro Aoki; Rina Ando; Tetsuo Yamaguchi; Hajime Matsumura; Tetsuya Matsumoto
A 49-year-old male presented with continuous recurrent chronic gluteal pyoderma. A total surgical excision of a subcutaneous abscess, followed by skin graft surgery, was performed. Three days postsurgery, skin engraftment failure was observed with local infection signs, including pain and
Annals of Plastic Surgery | 2014
Natsuki Sakamoto; Hajime Matsumura; Takako Komiya; Ryutaro Imai; Ahmatjan Niyaz; Katsueki Watanabe
AbstractA combination of skin grafts and local flaps is widely used in the reconstruction of syndactyly of the toes. Covering the skin defect without skin grafts on the unilateral side of the toe is preferred, and for this purpose, a rotated flap from the plantar area is typically used. However, the flap can become ischemic or congested in some cases. To avoid this, we elevated a plantar flap with the plantar cutaneous venous arch using a triangular venous flap and covered the lateral side of the web in 7 cases of syndactyly. The dorsal flap was used to create the new web, and the opposite lateral side was reconstructed using a skin graft. The flap circulation was stable, the pedicle of the flap was narrow, and the flap relocation was simple. No flap in any patient showed any evidence of congestion or ischemia. Follow-up demonstrated that the new web was patent in all cases, with no evidence of contraction.
Injury-international Journal of The Care of The Injured | 2008
Ryutaro Imai; Hajime Matsumura; Ryuji Uchida; Katsueki Watanabe