Objective:To summarize the clinical characteristics of children with dystonia 28 (DYT28) caused by KMT2B gene variations so as to improve clinicians′ understanding of the disease. Methods:The clinical manifestations, treatment and gene variation data of 11 children with DYT28 caused by KMT2B gene variations were retrospectively collected and analyzed.The subjects were recruited from the Department of Neurology, Beijing Children′s Hospital, Capital Medical University from March 2018 to January 2021.The patients were followed up. Results:There were 8 males and 3 females.The age at onset was ranging from 1 month to 6 years without inducement.Eight cases were gene-ralized dystonia and 3 cases were multifocal dystonia.The initial symptoms of 7 cases were unilateral or bilateral lower limbs tiptoeing.Four cases presented dysarthria, retching or swallowing difficulties at onset.As the disease progressed, all the cases had laryngeal dystonia, 10 cases had lower limbs dystonia, and 8 cases had upper limbs dystonia.Six cases were complicated with other dyskinesia symptoms.Ten cases had varying degrees of short stature, microcephalus, micrognathia, musculoskeletal abnormalities, intellectual disability, endocrinopathies and sleep difficulties.The brain magnetic resonance imaging showed abnormal in only 1 case.Eleven KMT2B gene pathogenic variants were found, including 8 frameshift variants, 1 in-frame variant and 2 missense variants.Four variants were novel.Eleven cases were followed up at the age of 1 year and 7 months to 17 years and 9 months.One case wasn′t given therapy.The dystonia in 3 cases was mildly improved after medication.Dysfunction of urination and defecation was disappeared in 1 case after medication.The symptom of 6 cases had no improvement after drug therapy.Among the above 6 cases, 5 drug refractory cases had deep brain stimulation, and their dystonia symptoms are all obviously improved; 2 cases had normal control of urination and defecation after deep brain stimulation.The motor scores in the Burke-Fahn-Marsden dystonia rating scale were improved by 55.8%-90.7%, and the disability scores were improved by 14.8%-69.6%. Conclusions:DYT28 caused by KMT2B gene variations is one of the most common and early-onset genetic dystonia in children.The dystonia symptom progresses from local parts to the whole body, prominently involving laryngeal muscles and lower limbs.Control of urination and defecation requires attention.Patients with mild dystonia symptoms can be effectively treated by drugs.However, patients with severe dystonia symptoms were drug refractory, and their dystonia symptoms can be effectively improved by deep brain stimulation.

Objective To investigate the safety of using a self-made new type non-inflatable retractor for transoral endoscopic thyroidectomy via submental and vestibular approach(TOETSMVA).Methods A retrospective analysis was conducted on the surgical records of 119 cases of unilateral thyroid lobe tumor from January 2021 to June 2022.Among them,37 cases underwent non-inflatable TOETSMVA by using a new type non-inflatable retractor(non-inflatable group),37 cases underwent traditional inflatable TOETSMVA(inflatable group),and 45 cases underwent traditional open anterior cervical thyroid surgery(open group).The differences in surgical indicators,postoperative complications,and patient satisfaction with incision were compared among the three groups.Results Compared with the open group,the non-inflatable group had longer operation time[(131.0±20.1)min vs.(81.1±15.7)min,P=0.000],but less intraoperative blood loss[19(15,27)ml vs.30(25,37)ml,P=0.000],lower pain score on the first day after surgery[(4.8±2.1)points vs.(6.4±1.9)points,P=0.000],and higher patient's satisfaction with the incision(the number of cases of very dissatisfied,dissatisfied,satisfied,comparatively satisfied,and very satisfied were 0,0,6,16,15 vs.4,3,19,17,2,P=0.000).Compared with the inflatable group,the non-inflatable group had shorter surgical time[(131.0±20.1)min vs.(141.8±22.9)min,P=0.019],and there were no statistically significant differences in intraoperative bleeding volume,pain score on the first day after surgery,and patient satisfaction with the incision(P＞0.05).There were no statistically significant differences in the number of lymph node dissection,total postoperative drainage volume,and parathyroid hormone(PTH)levels on the first day after surgery among the three groups(P＞0.05).Postoperative bleeding occurred in 1 case in the open group,and 1 case of hoarseness and 1 case of subcutaneous ecchymosis of the neck were noted in the non-inflatable group.No tracheoesophageal injury,severe subcutaneous emphysema,hypercapnia,or gas embolism happened among the three groups.Conclusions The new type non-inflatable retractor can effectively maintain space during TOETSMVA surgery.Compared with traditional open anterior cervical thyroid surgery and conventional inflatable TOETSMVA,it has better surgical safety.