Objective:To investigate the reasons for efficacy heterogeneity analysis of 3 patients with pantothenate kinase associated neurodegeneration (PKAN) from one family after deep brain stimulation (DBS).Methods:Three PKAN patients with the same PANK2 gene mutation from one family, admitted to and accepted bilateral subthalamic nucleus (STN)-DBS in our hospital from May to August 2021, were selected. The clinical manifestations, including general condition, medical history, symptoms, and signs, of these 3 patients were collected; Burkefahn-Marsden Dystonia Movement Rating Scale (BFMDRS) scores and surface electromyography results were analyzed and compared before DBS and 2 weeks and 6 months after DBS. Results:The clinical phenotype of these 3 patients had obvious heterogeneity: patient 1 had the latest onset age and shortest duration, and the main manifestation included abnormal body activity and forced postures, without obvious body deformation; preoperative surface electromyography suggested that the involuntary muscle contractions intensity was the smallest, and involuntary movements characterized by alternating patterns of contractile discharge activity were the predominant. The patient 2 and patient 3 had early onset age and long course of disease with gradually aggravated disease, and manifested as lower limb claudication and involuntary limb torsion; patient 3 also had marked limb deformities; preoperative surface electromyography showed high intensity of involuntary muscle contraction and torsional spastic dystonia characterized by co-contractile firing activity. The BFMDRS scores and surface electromyography results of the 3 patients after DBS were significantly improved as compared with those before surgery, with obvious heterogeneity; the improvement rates of BFMDRS scores of patient 1, 2 and 3 were 88.1%, 60.5%, and 43.2%, and the improvement rates of surface electromyography were 82.36%, 63.79% and 72.25%, respectively,at 6 months after surgery as compared with those before surgery.Conclusion:PKAN exhibits complicated clinical heterogeneity, which is one of the reasons for efficacy heterogeneity for PKAN after DBS.

Objective:To investigate the reasons for efficacy heterogeneity analysis of 3 patients with pantothenate kinase associated neurodegeneration (PKAN) from one family after deep brain stimulation (DBS).Methods:Three PKAN patients with the same PANK2 gene mutation from one family, admitted to and accepted bilateral subthalamic nucleus (STN)-DBS in our hospital from May to August 2021, were selected. The clinical manifestations, including general condition, medical history, symptoms, and signs, of these 3 patients were collected; Burkefahn-Marsden Dystonia Movement Rating Scale (BFMDRS) scores and surface electromyography results were analyzed and compared before DBS and 2 weeks and 6 months after DBS. Results:The clinical phenotype of these 3 patients had obvious heterogeneity: patient 1 had the latest onset age and shortest duration, and the main manifestation included abnormal body activity and forced postures, without obvious body deformation; preoperative surface electromyography suggested that the involuntary muscle contractions intensity was the smallest, and involuntary movements characterized by alternating patterns of contractile discharge activity were the predominant. The patient 2 and patient 3 had early onset age and long course of disease with gradually aggravated disease, and manifested as lower limb claudication and involuntary limb torsion; patient 3 also had marked limb deformities; preoperative surface electromyography showed high intensity of involuntary muscle contraction and torsional spastic dystonia characterized by co-contractile firing activity. The BFMDRS scores and surface electromyography results of the 3 patients after DBS were significantly improved as compared with those before surgery, with obvious heterogeneity; the improvement rates of BFMDRS scores of patient 1, 2 and 3 were 88.1%, 60.5%, and 43.2%, and the improvement rates of surface electromyography were 82.36%, 63.79% and 72.25%, respectively,at 6 months after surgery as compared with those before surgery.Conclusion:PKAN exhibits complicated clinical heterogeneity, which is one of the reasons for efficacy heterogeneity for PKAN after DBS.

Objective Deep brain stimulation (DBS) can greatly improve the clinical symptoms of Parkinson's disease (PD),but it can poorly improve the similar clinical symptoms of multiple system atrophy P-type (MSA-P);therefore,identification is a necessity for the two diseases before DBS is carried out on these patients;surface electromyography (sEMG) was employed to analyze the surface electromyographic characteristics associated with tremor and rigidity of PD and MSA-P to explore the role of sEMG in the differential diagnosis of PD and MSA-P.Methods Twenty patients with PD and 25 patients with MSA-P,admitted to our hospital from June 2013 to January 2015,were enrolled in the study.The sEMG was performed on all patients on the 2nd d of hospitalization.Tremor frequency,tremor sEMG activity intensity and postural tremor latency were analyzed.Synchronous sEMG activity intensity during passive activities was analyzed.Root mean square (RMS) in two states was calculated,and t-test was applied to compare tremor frequency,postural tremor latency and sEMG activity intensity.Results The incidence of rest tremor in MSA-P patients was 36％ and that in PD patients was 60％,with significant difference (P＜0.05).And the incidence ofpostural tremor in MSA-P ones was 44％ and that in PD ones was 35％,with significant difference (P＜0.05).Besides,the postural tremor latency in MSA-P patients was significantly longer than that in PD patients ([9.3±3.2] s vs.[5.3±2.1] s,P＜0.05).Thepostural tremor and rest tremor frequencies of MSA-P patients ([7.3±2.1] and [6.4±3.6]-Hz) were significantly higher than those in PD patients ([5.3±2.4] and [4.9±1.2] Hz,P＜0.05).In rest tremor,RMS of flexor and extensor in MSA-P patients was significantly decreased as compared with that in PD patients (P＜0.05);in postural tremor,RMS of flexor and extensor in MSA-P patients was significantly decreased as compared with that in PD patients (P＜0.05).During passive activities,RMS of extensor in MSA-P patients was statistically higher than that in PD patients ([27.927.9± 11.4] vs.[18.318.3±6.4] μV,P＜0.05),while there was no significant difference between RMS of flexor in MSA-P and PD patients ([31.1±13.6] vs.[29.2±8.9] μV,P＞0.05).Conclusion The sEMG can be applied in the preoperative differential diagnosis for DBS of PD and MSAP.