The study aimed to design a reliable and straightforward
PBM method by implanting a medical scattering fiber above surgically exposed spinal cord in SCI patients. Moreover, the safety of this method was examined. Twelve patients with acute SCI (ASIA B) requiring posterior
decompression were recruited. The medical scattering fiber was implanted above the spinal cord, and was continuously irradiated at 810 nm, 300 mW, 30 min/day, once per day for 7 days. The vital signs (temperature, blood pressure, respiratory rate, heart rate, and oxygen saturation),
infection indicators (WBC, NEUT,
hs-CRP, and PCT), photo-
allergic reaction indicators (Eosinophil and Basophil), coagulation function indicators (PT, APTT, TT) and neurological stability indicators (ASIA sensory and motor scores) were recorded to evaluate the safety of
PBM. Three months after surgery, 12 patients completed follow-up. In our study, direct
PBM on SCI site did not cause clinically pathologic changes in vital signs of the patients. All patients had higher WBC, NEUT, and
hs-CRP at day 3 during irradiation than those before surgery, and returned to normal at day 7. The changes in Eosinophil and Basophil that were closely associated with
allergic reactions were within normal limits throughout the course of irradiation. The coagulation function (PT, APTT, and TT) of patients were also in the normal range. The ASIA sensory and motor scores of all patients had no changes throughout the irradiation process. However, in the follow-up, both ASIA sensory and motor scores of all patients had minor improvement than those in pre-irradiation, and 7 patients had adverse events, but they were not considered to be related to
PBM. Our study might firstly employ direct
PBM in the SCI by using scattered
optical fibers. In a limited sample size, our study concluded that direct
PBM at the site of SCI would not produce adverse effects within the appropriate irradiation parameters. The method is safe, feasible, and does not add additional
trauma to the patient. Our preliminary study might provide a new methodology for the clinical
PBM treatment of acute SCI.