Does it Matter the Volume of Injectate on the Outcome of Ultrasound-guided Perineural Injection for Carpal Tunnel Syndrome

Exclusion Criteria

• •1- Age less than 20 years 2- severe CTS (abductor policies brevis muscle atrophy with distal latency time \>6.5 MS).
• •3- MN electrophysiology study revealing absent potentials. 4- its cross-sectional area (CSA) \>15 mm2 by sonographic checkup. 5- previous surgery of carpal tunnel. 6- previous wrist injection within 3 months 7- history of peripheral nerve injuries (brachial plexopathy, cervical radiculopathy or thoracic outlet syndrome) 8- CTS due to systemic causes, for example, endocrinal and/or pregnancy, rheumatoid arthritis, gouty or psoriatic osteoarthritis.
• •9- concurrent use of antihistaminic, or cortisone. 10- Participant refusal. 11- local infection. presence of coagulopathy, and/or allergy to the included medications were also points for patients' exclusion from the study