Peripheral Nerves, Anatomy and Physiology of

The Effects of Photobiomodulation Therapy in Cubital Tunnel Syndrome, Clinical Trial

Aim: We aimed to evaluate the effects of laser therapy together with rest splint and exercise on muscle strength, function, activities of daily living, and pain in individuals suffering from cubital tunnel syndrome (CuTS) by comparing it with placebo treatment. Materials and Methods: This prospective, single-blind, and randomized controlled study was conducted with 64 patients with CuTS in total. They were divided into two groups by randomization: Group 1 (n = 32) was provided with low-energy laser therapy + splint + exercise, and Group 2 (n = 32) was provided with low-energy sham laser therapy + splint + exercise. Patients in both groups received resting splints and nerve release exercises. Pretreatment and posttreatment (3rd week, 3rd month) evaluations were made with the Visual Analog Scale (VAS), the Quick Disability of Arm, Shoulder, and Hand Questionnaire, hand grip strength, fingertip grip strength, the Patient-Rated Ulnar Nerve Evaluation Scale (PRUNES), and Short Form-12. An electrophysiological evaluation was performed at baseline and at the 3rd month. Results: We observed significant improvements in both groups regarding pain, function, muscle strength, health profile, and quality of life in the early posttreatment (3rd week) stage and at the 3rd-month follow-up. When both groups were compared, a significant difference was determined between the VAS-Rest, VAS-Movement, PRUNES-Pain, PRUNES-Function, and PRUNES-Total parameters in the posttreatment (3rd week follow-ups), as well as PRUNES-Pain scores in the post-treatment (3rd month) stage, of the groups in favor of those in Group 1 (p < 0.05). Conclusion: The findings of our study have shown that in the treatment of CuTS, laser treatment is superior to placebo in the short term, but they have equivalent effects in the medium term. Further studies with large patient populations are needed to provide more diverse information about the therapeutic effectiveness of low-intensity laser therapy.

High-resolution in vivo imaging of peripheral nerves using optical coherence tomography: a feasibility study

OBJECTIVE

Because of their complex topography, long courses, and small diameters, peripheral nerves are challenging structures for radiological diagnostics. However, imaging techniques in the area of peripheral nerve diseases have undergone unexpected development in recent decades. They include MRI and high-resolution sonography (HRS). Yet none of those imaging techniques reaches a resolution comparable to that of histological sections. Fascicles are the smallest discernable structure. Optical coherence tomography (OCT) is the first imaging technique that is able to depict a nerve's ultrastructure at micrometer resolution. In the current study, the authors present an in vivo assessment of human peripheral nerves using OCT.

METHODS

OCT measurement was performed in 34 patients with different peripheral nerve pathologies, i.e., nerve compression syndromes. The nerves were examined during surgery after their exposure. Only the sural nerve was twice examined ex vivo. The Thorlabs OCT systems Callisto and Ganymede were used. For intraoperative use, a hand probe was covered with a sterile foil. Different postprocessing imaging techniques were applied and evaluated. In order to highlight certain structures, five texture parameters based on gray-level co-occurrence matrices were calculated according to Haralick.

RESULTS

The intraoperative use of OCT is easy and intuitive. Image artifacts are mainly caused by motion and the sterile foil. If the artifacts are kept at a low level, the hyporeflecting bundles of nerve fascicles and their inner parts can be displayed. In the Haralick evaluation, the second angular moment is most suitable to depict the connective tissue.

CONCLUSIONS

OCT is a new imaging technique that has shown promise in peripheral nerve surgery for particular questions. Its resolution exceeds that provided by recent radiological possibilities such as MRI and HRS. Since its field of view is relatively small, faster acquisition times would be highly desirable and have already been demonstrated by other groups. Currently, the method resembles an optical biopsy and can be a supplement to intraoperative sonography, giving high-resolution insight into a suspect area that has been located by sonography in advance.