Purpose of the study: We proposed a new electrophysiological parameter medial plantar-to-radial amplitude ratio (MPRAR), similar to sural-to-radial amplitude ratio (SRAR), in the diagnosis of distal sensory polyneuropathy (DSP), based on the concept that distal nerves are affected more and earlier than proximal nerves in axonal neuropathies. We aimed to investigate the diagnostic sensitivity of this parameter in diabetic DSP, together with sensitivities of SRAR and medial plantar (MP) nerve action potential (NAP) amplitude. Materials and Methods: In 124 healthy controls and 87 diabetic patients with clinically defined DSP and normal sural responses, we prospectively performed sensory NCSs, and evaluated the MP NAP amplitude, MPRAR and SRAR values. We determined the lower limits of normal (LLN) of these parameters in the healthy controls and calculated their sensitivities and specificities in detecting DSP in diabetic patients. Results: MP nerve amplitude and MPRAR values were significantly lower in the patient group, compared to controls. However, SRAR values did not differ significantly between the two groups. The LLN of MP NAP amplitude was found to be 4.1. The cut-off values for SRAR and MPRAR were determined as 0.24 and 0.16, respectively. MPRAR was abnormal in 21.8% of patients. However, the most sensitive parameter in detection of DSP was MP NAP amplitude, which showed a sensitivity of 31% and a specificity of 100%. Conclusions: Although MPRAR is more sensitive than SRAR in detecting DSP, it does not provide additional diagnostic yield to the assessment of MP NCS alone in diabetic DSP patients with normal sural responses.
28 February 2013 in Case Reports in Neurological Medicine
Postcoital artery dissection is a rare condition. Here we report a 40-year-old male patient with painful Horner syndrome related to postcoital internal carotid artery (ICA) dissection. In neurologic examination of the patient, semiptosis, enophthalmus, and myosis were observed on the left side. There were no carotid bruits. On T1-weighted and fat-suppressed cranial MRI, hyperintensity consistent with intramural hematoma was observed within cervical and temporal petrous segments of left ICA. On cervical and cranial MRA, marked decrease in the calibration of C1 and C2 segments of the left ICA was remarkable. The patient was diagnosed as left ICA dissection and anticoagulant therapy was initiated. A prominent improvement was noted in clinical findings during two months of followup period.
Introduction: Juvenile myasthenia gravis (JMG) is a rare autoimmune disorder with a variable clinical course and limited pediatric-specific treatment guidelines. Objective clinical scales, such as the Quantitative Myasthenia Gravis (QMG) Score and the Pediatric Myasthenia Gravis Quality of Life 15 (PM-QOL15), may support individualized management, but their role in routine practice remains underexplored. Methods: We retrospectively reviewed 10 seropositive JMG patients followed at a single tertiary neuromuscular clinic between 2014 and 2024. All patients underwent a systematic assessment with QMG at each visit, while PM-QOL15 was administered at the final visit. Clinical data, comorbidities, antibody status, treatment modalities, and outcomes were analyzed. Associations between treatment strategies, comorbidities, and scale scores were explored using appropriate statistical methods. Results: Seven patients (70%) underwent thymectomy, resulting in a reduction in mean QMG scores from 7.7 to 2.4, though residual relapses were observed. Chronic intravenous immunoglobulin (IVIG) therapy, administered to 70% of patients, did not significantly reduce relapse rates or steroid exposure and was associated with higher QMG scores in the second year, suggesting use in more severe phenotypes rather than therapeutic efficacy. Prolonged corticosteroid therapy did not improve remission time or relapse frequency and was complicated by major adverse effects in two patients. Timing of azathioprine initiation showed no significant correlation with relapse frequency. PM-QOL15 correlated strongly with mean QMG (r = 0.88, p < 0.001), reflecting cumulative disease burden. Patients with comorbidities required longer stabilization, although differences were not statistically significant. Conclusions: The routine integration of QMG and PM-QOL15 into follow-up may facilitate the earlier recognition of subclinical deterioration, provide objective measures of treatment response, and guide personalized management in JMG. Thymectomy showed benefit in selected patients, while the long-term roles of IVIG and corticosteroids remain uncertain. Larger multicenter prospective studies are warranted to confirm these findings and refine evidence-based strategies for pediatric JMG.
Background: Sleep-disordered breathing (SDB) is increasingly recognized in myasthenia gravis (MG), yet potential differences in sleep respiratory patterns between antibody-defined MG subtypes remain poorly understood. We aimed to evaluate sleep disorders and polysomnographic characteristics in patients with acetylcholine receptor antibody–positive (AChR-MG) and muscle-specific tyrosine kinase antibody–positive (MuSK-MG) generalized MG. Methods: Eighteen clinically stable MG patients (9 AChR-MG, 9 MuSK-MG) and 9 healthy controls underwent attended overnight polysomnography followed by the Multiple Sleep Latency Test (MSLT). Standardized sleep questionnaires and MG clinical scales were administered to assess sleep-related symptoms and disease severity. Results: Obstructive sleep apnea was detected in 89% of AChR-MG and 78% of MuSK-MG patients. Both MG subgroups showed significantly higher apnea–hypopnea index values compared with controls ( p < 0.05). Although overall AHI severity did not differ significantly between antibody groups, distinct respiratory patterns were observed. Respiratory events clustered predominantly during REM sleep in AChR-MG, whereas MuSK-MG patients exhibited more frequent events during NREM or supine sleep. Conclusions: Sleep-disordered breathing appears to be common in MG, but polysomnographic patterns may differ according to antibody subtype. REM-predominant respiratory events in AChR-MG and NREM or positional predominance in MuSK-MG may reflect differences in muscle involvement between these subtypes. These findings suggest that antibody-specific mechanisms may influence nocturnal respiratory dysfunction in MG and highlight the importance of targeted sleep assessment in this population.