Objective To evaluate the application of cough reflex testing with various concentrations of citric acid for dysphagia post stroke. Methods 20 normal controls (NC), 20 stroke patients with dysphagia (SD) and 20 stroke patients without dysphagia (SND) were tested with cough reflex inhalated 4 kinds of dosage of citric acid: 0.2 mol/L, 0.4 mol/L, 0.6 mol/L and 0.8 mol/L. Results The incidence of pass (coughed twice or more) decreased in the SD compared with those in the NC as inhalated citric acid of 0.2 mol/L and 0.4 mol/L (P< 0.05), and decreased under 0.4 mol/L compared with the SND (P<0.05). There was no significant difference between the SND and the NC (P>0.05). 90% of the NC passed as inhalated citric acid of 0.4 mol/L; however, it was 45% in the SD, and increased when they inhalated more dosage of citric acid (P<0.05). The incidence of pass decreased under 0.2 mol/L citric acid in the SND compared with other concentration (P<0.05). The result of the test was reliable interrater (κ=0.97). The incidence of cough was consistent of 96.8% with the same concentration. No asthma and asphyxia was observed. Conclusion Cough reflex testing with citric acid inhalation can be used to assess the defensive function of airway in lower concentration for dysphagia after stroke.

Objective:To investigate the clinical features, molecular etiology, and treatment of a family with Treacher Collins Syndrome 2 (TCS2).Methods:Information of the proband (female, 8 years old) including medical history and family history was collected. Physical examination and examinations concerning laboratory, audiology, and radiology were performed on the proband. Physical examination was also performed on the family members. Genomic DNA of proband was extracted for whole exome sequencing, and then the genomic DNA of family members was extracted for Sanger sequencing. POLR1D and TCS2 related literatures published before August 31,2023 were searched and sifted in PubMed and CKNI databases. The clinical characteristics of TCS2 were summarized. Results:The proband had poor hearing since childhood, with pure tone audiometry indicating conductive hearing loss. She had a smaller jaw, bilateral preauricular fistulas and cup-shaped ear deformities. Temporal bone CT scan revealed deformities in the left external ear canal, bilateral middle ear and inner ear. A bone-conduction hearing aid device was surgically implanted, resulting in restoration of almost normal hearing levels. The proband′s mother also had a slightly smaller jaw. Genetic analysis revealed a novel heterozygous variant NM_015972.4:c.38_47del in the POLR1D gene in the proband, which was inherited from her mother. A review of the literature revealed no clear evidence of genotype-phenotype correlation in TCS2. Conclusions:Molecular diagnosis plays a vital role in the diagnosis of TCS2. Patients with normal facial phenotype may be carriers of pathogenic variants in the POLR1D gene and have the risk of passing it to the offsprings with complete penetrance. Proper bone conductive hearing devices can improve the quality of life of TCS2 patients.