Biomedical subjects

Yoshiyuki Yonehara

Publications and source records attributed to Yoshiyuki Yonehara.

6 recordsLinked to original sources

PubMed2005

Treatment of zygomatic fractures without inferior orbital rim fixation.

Zygomatic fractures can be associated with functional and esthetic problems. Recent improvements in surgical techniques and materials have enabled stable fixation of zygmomatic fractures. Multiple-point fixation is most commonly used for internal fixation. Generally, reduction and fixation are performed through lateral brow, subciliary, temporal, or intraoral incisions (three-point fixation). Our experience indicates that postoperative scarring and sensory disturbances are caused by a subciliary incision with inferior orbital rim fixation. It is thus recommended that inferior orbital rim fixation with mini- or microplates be avoided. In patients in whom the fracture does not involve the orbital floor, reduction of the zygoma and zygomatic arch through a temporal incision is performed at this institution. Fixation of the lateral zygomaticomaxillary buttress and anterior wall of the maxilla with miniplates through an intraoral incision is also performed. If necessary, zygomaticofrontal suture fixation with a miniplate or wire is performed through a lateral brow incision. The status of inferior orbital rim reduction is confirmed by palpitation. Inferior orbital rim fixation with mini- or microplates is recommended for reduction of comminuted fractures and orbital floor fractures with herniation of internal orbit components. Patients who did not undergo inferior orbital rim fixation were free of inferior orbital rim deformity, diplopia, and postreduction rotation.

Adolescent↗

PubMed2004

Topical negative pressure using a drainage pouch without foam dressing for the treatment of undermined pressure ulcers.

UNLABELLED: Topical negative pressure is gaining popularity as an acute and chronic wound management technique. In general, foam dressing is applied to the wound surface to maintain negative pressure. Due to the potential for clogging by the foam dressing, topical negative pressure cannot be used when there is a high volume of necrotic tissue or massive infection present. In this study, topical negative pressure was applied using a drainage pouch without any dressing. Topical negative pressure was applied to 8 patients with 9 pressure ulcers complicated by undermining. This approach was effective in the treatment of all 9 ulcers and allowed the wounds to be visualized while maintaining negative pressure. Since this technique can be performed without foam dressing, it can be used to treat early-stage infectious pressure ulcers in which there is a lot of necrotic tissue. CONCLUSION: Topical negative pressure without dressing is an extremely effective treatment of pressure ulcers complicated by undermining.

Adult↗

PubMed2004

Comparison of bacteria-retaining ability of absorbent wound dressings.

Fibrous materials in some modern absorbent wound dressings have the ability to sequester and retain bacteria; however, this ability varies according to the nature of the fibres. We studied the bacterial retention capacity of alginate and carboxymethylcellulose dressings, using an infected skin ulcer model on the backs of rats. Wound surfaces were inoculated with either Staphylococcus aureus or Pseudomonas aeruginosa at a concentration of 1.5 x 10(6) colony-forming units per wound. AQUACEL; Hydrofiber;, Kaltostat; or Sorbsan; were applied to the contaminated wounds for 12 h. Each dressing was then divided into two pieces. Total viable bacterial count within the dressing was calculated using one piece, and bacterial count released from the dressing into physiological saline was determined using the other piece, enabling bacterial retention rate to be calculated. Bacterial counts in tissue were also determined. Each dressing was tested on each of 10 wounds contaminated with each bacterium. Statistical analyses were performed using one-way analysis of variance (ANOVA) for replicated measures combined with Duncan's multiple comparison test. AQUACEL; Hydrofiber; dressing was most effective in its ability to retain both Staphylococcus aureus and Pseudomonas aeruginosa (p < 0.05). Bacterial counts in tissue showed no significant change with respect to pathogen or the type of dressing used. It can be concluded that the bacterial retaining ability of AQUACEL; Hydrofiber; dressing was found to be significantly higher than that of alginate dressings in an infected animal wound model.

Absorption↗

PubMed2004

Development of an experimental model of infected skin ulcer.

A model of infected skin ulceration could prove useful in assessing the clinical effectiveness of antimicrobial ointments and dressings. However, no such models have been previously established. Three types of wound were induced in rats: full-thickness wounds covered with gauze, burn wounds and wounds resulting from mechanical trauma. Wounds were inoculated with S. aureus or P. aeruginosa. Persistent infected wounds were observed only in full-thickness wounds covered with gauze. In a second experiment, colonies of P. aeruginosa or S. aureus were counted within 15 x 15 mm full-thickness wounds covered with gauze. Wounds were inoculated with 1.0 x 10(6) colony-forming units (CFU) of P. aeruginosa or S. aureus and then sealed to ensure an enclosed environment. Tissue bacterial counts exceeded 10(6) CFU/g from the next day until day 9 after infection. Bacterial counts exceeded 10(8) CFU/ml in wound exudate collected between days 1 and 7. We have developed a model of wound infection in which persistence of infection can be achieved for 9 days following ulceration due to the application of gauze to the base of a full-thickness wound.

Animals↗

PubMed2003

Complications associated with gradual cranial vault distraction osteogenesis for the treatment of craniofacial synostosis.

Distraction osteogenesis has become a standard technique for craniomaxillofacial reconstruction. The authors performed gradual cranial vault distraction osteogenesis in 19 patients with craniosynostosis to study the outcome and complications of this procedure. Postoperative infections developed around the shaft puncture wounds in four patients, including one who required surgical removal of the device. Advanced bone was deformed in one patient. In another, the expansion device was exposed, resulting in a postoperative scar. Despite these complications, the cranium was successfully expanded in all patients.

Child↗

PubMed2002

CATCH 22 Syndrome.

CATCH 22 syndrome is characterized by cardiac defects, abnormal facial features, thymic hypoplasia, cleft palate, and hypocalcemia. It results from a deletion within chromosome 22q11. This syndrome is not a simple disease. It includes DiGeorge syndrome, conotruncal anomaly face syndrome, and velocardiofacial syndrome. The authors report two cases of CATCH 22 syndrome.

Abnormalities, Multiple↗