Neurite growth of trigeminal ganglion neurons in vitro with near-infrared light irradiation.

Trigeminal ganglion (TG) neurons play an essential role in the sensory nerves of the face. Damaged TG neurons resulting from the accidental and non-intentional nerve lesions, commonly identified as neuropathic pain, which is known to cause intense pain and sensory abnormalities. For the treatment, surgical methods are conducted when the pharmacological treatment fails to provide satisfactory recovery. However, the process of surgery or drug intake can burden the patient or cause side effects. One of the logical choices of study becomes photobiomodulation (PBM) referred to as therapeutic approaches based on the interactions of visible or near-infrared (NIR) photons with biomolecules inside cells or tissues. In this study, we constructed a PBM illumination setup to stimulate the cultured primary TG neurons and compared the growth morphology between the non-irradiated control group and irradiation group with NIR laser of 808 nm wavelength. In addition, we applied various radiant exposures of 1, 2, and 10 J/cm2 with different pulse frequencies of 1, 10, and 100 Hz. We found that PBM could promote neurite growth of TG neurons, and it works at relatively low energy densities at 1 and 2 J/cm2. The irradiation group in the pulsed wave mode with the frequency of 10 Hz was found to be the most effective when compared to other frequencies. Thus, PBM on TG neurons facilitated neuronal growth in vitro in a dose and frequency-dependent fashion. PBM may provide a potential therapeutic approach to treat damaged peripheral nerves.

Short segment percutaneous pedicle screw fixation after direct spinal canal decompression in thoracolumbar burst fractures: An alternative option.

OBJECTIVE: To investigate the surgical results of percutaneous pedicle screw fixation (PPSF) after spinal canal decompression via a small laminectomy for the treatment of thoracolumbar burst fractures. METHOD: Twenty-seven patients underwent PPSF after spinal canal decompression via small laminectomies between April 2009 and April 2015. Inclusion criteria consisted of a single-level, closed, thoracolumbar burst fracture and neurological symptoms. Decompression was performed via a small laminectomy, followed by PPSF, including at the level of the fractured vertebra. Cobb angle, vertebral wedge angle, and vertebral body index were each measured from lateral radiographs before and after surgery, and at last follow-up. Neurological assessment was made using the Frankel grading system. RESULTS: The average follow-up period was 26 months. The preoperative average Cobb angle was 15.8°â€¯±â€¯6.6°, and significantly decreased to 6.5°â€¯±â€¯6.2° postoperatively (p < 0.001). Average Cobb angle at last follow-up increased slightly to 8.9°â€¯±â€¯6.9°, but this was not significant (p = 0.112). The preoperative average vertebral wedge angle was 20.6°â€¯±â€¯6.3°, and decreased significantly to 12.2°â€¯±â€¯6.2° postoperatively (p < 0.001). The vertebral body index significantly decreased from 0.58 ±â€¯0.11 to a postoperative value of 0.78 ±â€¯0.10 (p < 0.001). Clinically, no patient deteriorated subsequent to surgery. CONCLUSION: Percutaneous pedicle screw fixation after spinal canal decompression via small laminectomy provides significant kyphotic correction and improved neurological outcome while offering decreased surgical morbidity. This may be applied as an effective primary surgery in select patients with TLBFs with neurologic symptoms.