This study concerned the effect of Ga-Al-As diode laser irradiation (780 nm, continuous wave, 31.8 J/s/cm2, spot size od 0.2 mm, 3 minutes/dose) on hyperalgesia induced in the hind paw of rats by injecting carrageenin. The pressure-pain thresholds of hind paws were measured by the Randall-Selitto test for evaluation of hyperalgesia. Two doses of laser irradiation, given to the inflamed region immediately before and after the injection of carrageenin, partially (approximately 50%) inhibited the occurrence of hyperalgesia accompanied with a progression of inflammation. This analgesic effect was equal to that of indomethacin (4 mg/kg, i.o.). In another group, the hyperalgesia was removed almost completely for at least 24 hours by one dose of laser irradiation, which was given 3 hours after the carrageenin injection, whereas the edema was not inhibited. This analgesic effect, however, was partially (approximately 50%) antagonized with a dose of 10 mg/kg (i.p.) of naloxone and totally inhibited with 30 mg/kg. These results suggest that low-power laser irradiation on inflamed regions of carrageenin-treated rats has a marked analgesic effect and that certain mechanisms that are not related to endogenous opioids are involved in a part of the mechanisms of the analgesic effects.

The purpose of this survey is to identify the health-related quality of life (HRQOL) and cost-effectiveness of inpatient rehabilitation services for traumatic brain injury (TBI), spinal cord injury (SCI) and osteoarthritis of the hip in our rehabilitation hospital. Subjects were 112 patients who could answer the questions, did not have serious complications and stayed to our hospital more than 30 days. In this survey the EuroQOL utility score, visual analogue scale, and Functional Independence Measure (FIM) scores were applied at hospitalization and discharge. The mean FIM scores in TBI and SCI improved significantly at discharge. The EuroQOL utility score and Visual analogue scale (VAS) for the three groups also improved at discharge. The mean hospital cost per person in TBI, SCI and osteoarthritis of the hip were 1,462+504 thousand yen, 1,822+790 thousand yen and 1,389+407 thousand yen, respectively. The costs to obtain 1 quality adjusted life year (QALY) were 431+124 thousand yen, 425+551 thousand yen and 478+487 thousand yen, respectively. This survey indicates that in-hospital rehabilitation services for these three groups are cost-effective.