RESUMO
Objective: To analyze clinical features and electroneuromyography (ENMG) results of chronic mild occupational carbon disulfide poisoning cases. Methods: A total of 344 patients diagnosed with chronic mild occupational carbon disulfide poisoning based on GBZ 4-2002 Diagnostic Criteria of Occupational Chronic Carbon Disulfide Poisoning were selected as study subjects from 2006 to 2019 using the retrospective study method. Their clinical data was collected and analyzed. Results: The main symptoms of the study subjects were dizziness, headache, insomnia, dreaming, memory impairment, numbness and weakness in the distal extremities. Positive signs mainly included symmetrical glove and stocking distribution like sensory disorders in the distal extremities, and the weakening or absent Achilles tendon reflex and knee reflex. The incidence of symptoms and signs increased with the length of service (all P<0.01). The incidence of fundus and venous changes in patients was 41.3%, which increased with the length of service (P<0.01). ENMG examination showed varying degrees of abnormalities in the peripheral motor and/or sensory nerves in all patients, with a higher incidence of motor nerve abnormalities than sensory nerve abnormalities (21.1% vs 3.7%, P<0.01). The incidence of motor nerve abnormality was higher on the right side than the left side (23.7% vs 18.5%, P<0.01). The incidences of motor nerve abnormalities from high to low in the order were median nerve, common peroneal nerve, ulnar nerve and posterior tibial nerve (34.9% vs 27.9% vs 16.6% vs 5.1%, P<0.01). The incidences of sensory nerve abnormalities from high to low in the order were median nerve, ulnar nerve and sural nerve (5.2% vs 5.1% vs 0.7%, P<0.01). The incidences of left ulnar nerve, right ulnar nerve and right median nerve were higher in male patients than in female patients (15.2% vs 5.3%, 24.0% vs 11.7%, 44.8% vs 28.7%, all P<0.05), while the incidences of the left and right common peroneal nerve in lower extremity motor nerve were lower in male patients than in female patients (18.4% vs 52.1%, 21.2% vs 46.8%, all P<0.01). Conclusion: Chronic mild occupational carbon disulfide poisoning was mainly manifested as multiple peripheral nerve injury. ENMG results showed that the distal motor nerve conduction abnormalities were more sensitive than the sensory nerve conduction abnormalities, with a higher degree of impairment in the upper limb than the lower limb, and more impairment in the right side than the left side.
RESUMO
OBJECTIVE: To find the correlation between dorsal root ganglion location and abnormal superficial peroneal sensory nerve action potential (SNAP) response in L5 radiculopathy. METHOD: This retrospective study included thirty-three patients with unilateral L5 radiculopathy, who had no peripheral polyneuropathy, focal neuropathy or other metabolic disease and were under 60 years. 33 patients were classified to two groups: group I with an abnormal superficial peroneal SNAP response and group II with a normal superficial peroneal SNAP response. Using axial view of MRI, the location of dorsal root ganglion (DRG) of the study group was classified into intraspinal, intraforaminal and extraforaminal space. RESULTS: In group I, 71% of L4 dorsal root ganglion was located in intraforaminal space, and 14% in extraforaminal space and 64% of L5 DRG was in intraforaminal space and 14% in intraspinal. In Group II, 42% of L4 DRG was located in intraforaminal space, and 58% in extraforaminal and 26% of L5 DRG in intraforaminal space and 63% in extraforaminal space. Group I subjects were more located in the intraforaminal space than Group II subjects (p <0.05). CONCLUSION: In spite of belief that "radiculopathy involves the nerve root proximal to DRG", the significant proportion of dorsal root ganglion was located inside intraforaminal space. Thus the intraspinal lesion such as disc protrusion or spondylotic encroachment may compress DRG and cause abnormal findings of SNAP in EMG study.