The Role of Muscle Ultrasound in the Assessment of Peripheral Neuropathy
Bashaer H. Obayes, Zahraa A. Al-mudhafar, Zahid M. Kadhim, Qebas H. AlsultaniAbstract
Background:
Peripheral neuropathy (PN) is a group of disorders that affects peripheral nerves with variable pathologic and etiologic mechanisms.
Objectives:
The aims of this study are to measure muscle thickness and echogenicity and evaluate its role in the diagnosis of patients with different PN who were classified according to pathology (A: axonal, D: demyelinating, and M: mixed [axonal and demyelinating] PN).
Materials and Methods:
This is a case–control conducted in the Department of Neurophysiology at Al Imam Al Sadeq Teaching Hospital in Al-Hilla Governorate. It includes 135 (58 male and 77 female) with a diagnosis of PN by an experienced neurological confirmed by the history, physical examination, and electrodiagnostic study (nerve conduction study and electromyography). Also, Electrodiagnostic studies are used to classify patients according to the pathology into axonal, demyelinating, and mixed polyneuropathies. We matched 138 controls for age and sex with participants. The patient is examined and monitored “by high-resolution ultrasound” (Philips ultrasound machine with 12 MHz linear probes). We evaluate. The muscles in the lower limbs, including the tibialis anterior, the biceps femoris, and the abductor halluces brevis, as well as the muscles in the upper limbs, including the biceps brachialis, the flexor carpi radialis, and the first interosseous, are measured and analyzed for thickness and echogenicity. Results are compared between cases and controls and then matched between different types of polyneuropathies according to pathology.
Results:
The study indicated that there were statistically significant differences in the mean muscle thickness. In all tested muscles of the upper and lower limbs between patients and control group. The demyelinating group had less mean muscle thickness in biceps brachialis and tibialis anterior muscles than other groups, then the mixed group in biceps femoris and the first interosseous muscles, and lastly, the axonal group in. the flexor carpi radialis, and the abductor halluces brevis. All groups have a reduced muscle thickness of all examined muscles more than the control group. Also, there is a significant difference in echogenicity between different groups, with a demyelinating group showing a low percentage of normal echogenicity while a high percentage of normal echogenicity in axonal PN. All groups have hypoechogenicity of examined muscles more than the control group.
Conclusion:
Muscle ultrasound is a useful and complementary test for the diagnosis of patients with PN, differentiating between its variable pathologies.