No abstract

Platelet rich plasma (PRP) has attracted attention as a safe and cost-effective source of growth factors that stimulate cells to regenerate tissue. Bone marrow cells are also estimated as an effective material for treating chronic ulcers. With the same technique to concentrate PRP from peripheral blood, bone marrow aspirate was processed and marrow cells were concentrated as well as platelets. Impact of PRP derived from bone marrow aspirate (bm-PRP) and that from peripheral blood (pb-PRP) on wound healing of persistent ischaemic rabbits' limbs were observed. Full thickness skin defects were made on the thighs, which had been treated to be persistent ischaemic status 3 weeks previously. Saline, pb-PRP, and bm-PRP were injected into the wound floor, respectively. Skin defected areas on ischaemic limbs were significantly wider than those on non-ischaemic limbs. bm-PRP injected wounds showed a significantly smaller skin defect area compared with pb-PRP and ischaemic-saline wounds at all time points. Fluorescently dyed cells of bm-PRP, injected into the wounds, could be traced 4 weeks after, whereas those of pb-PRP could be traced no more than 2 weeks. Wound healing on an ischaemic limb was accelerated with bm-PRP, whereas pb-PRP could not show any significance from saline. This difference can be attributed to the kind of cells contained in the PRPs. Injection of bm-PRP is a good candidate for treating wounds on ischaemic limbs.

Currently, laser radiation is used routinely in medical applications. For infrared lasers, bone ablation and the healing process have been reported, but no laser systems are established and applied in clinical bone surgery. Furthermore, industrial laser applications utilize computer and robot assistance; medical laser radiations are still mostly conducted manually nowadays. The purpose of this study was to compare the histological appearance of bone ablation and healing response in rabbit radial bone osteotomy created by surgical saw and ytterbium-doped fiber laser controlled by a computer with use of nitrogen surface cooling spray. An Ytterbium (Yb)-doped fiber laser at a wavelength of 1,070 nm was guided by a computer-aided robotic system, with a spot size of 100 μm at a distance of approximately 80 mm from the surface. The output power of the laser was 60 W at the scanning speed of 20 mm/s scan using continuous wave system with nitrogen spray level 0.5 MPa (energy density, 3.8 × 10(4) W/cm(2)). Rabbits radial bone osteotomy was performed by an Yb-doped fiber laser and a surgical saw. Additionally, histological analyses of the osteotomy site were performed on day 0 and day 21. Yb-doped fiber laser osteotomy revealed a remarkable cutting efficiency. There were little signs of tissue damage to the muscle. Lased specimens have shown no delayed healing compared with the saw osteotomies. Computer-assisted robotic osteotomy with Yb-doped fiber laser was able to perform. In rabbit model, laser-induced osteotomy defects, compared to those by surgical saw, exhibited no delayed healing response.

Background:The frequency of encountering radiodermatitis caused by X-ray fluoroscopic procedures for ischaemic heart disease is increasing. In severe cases, devastating ulcers with pain, for which conservative therapy is ineffective, emerge. Radiation-induced ulcers are notorious for being difficult to treat. Simple skin grafting often fails because of the poor state of the wound bed. A vascularized flap is a very good option. However, the non-adherence of the well-vascularized flap with the irradiated wound bed is frequently experienced.Aim:To ameliorate the irradiated wound bed, bone marrow-derived platelet-rich plasma (bm-PRP) was delivered during the surgery.Materials and Methods:Four patients with severe cutaneous radiation injury accompanied by unbearable pain after multiple fluoroscopic procedures for ischaemic heart disease were treated. Wide excision of the lesion and coverage with a skin flap supplemented with bm-PRP injection was performed.Results:All patients obtained wound closure and were relieved from pain. No complication concerning the bone marrow aspiration and delivery of bm-PRP was observed.Conclusions:Supplementation of bm-PRP can be an option without major complications, time, and cost to improve the surgical outcome for irradiated wounds.

Radiation has many benefits and is an important treatment for cancer therapy. However, it also has unfavourable side-effects. Among these side-effects, the impairment of wound healing in the skin is a major problem in clinics. Although many attempts have been made to overcome this shortcoming, there are few effective treatments for impaired wound healing after irradiation. One reason for this is that it is hard to obtain good animal models for researching this topic. In this study, two different models were created and investigated. In one model, rectangular flaps were created on the backs of mice and irradiated while the other parts of their bodies were covered with a lead board. In another model, the lower limbs were exposed to radiation. In each model, several doses of irradiation were tested. Skin ulcers were created in the irradiated area, and the wound healing process was observed. In order to verify the usefulness of the model, adipose derived stromal cells were injected into the wound and the healing rate was calculated. In the flap model, the flaps contracted and formed linear scars. On the other hand, in the thigh model, 15 Gy irradiation resulted in slow wound healing but no strong inflammation or necrosis. The transplantation of adipose tissue derived stromal cells into the irradiated thigh wound improved the wound healing. This study suggested that irradiation of the lower limb at ∼ 15 Gy might be an appropriate model for basic research into wound healing in irradiated skin.