Objective:To observe the effect of different clinical factors on the level of parathyroid hormone (PTH) and to predict the possibility of permanent hypothyroidism (PHP) after total thyroidectomy (TT) by monitoring the levels of PTH in serum and drainage fluid after TT.Methods:Retrospective analysis was made on 150 patients who underwent TT for papillary thyroid carcinoma (PTC) in the Department of Thyroid Head and Neck Surgery in Jilin Cancer Hospital from Jan. 2020 to Aug. 2021. The changes of serum PTH were recorded at 1, 3, 7, 30 days and 6 months after surgery. The risk factors of postoperative hypoparathyroidism (HP) were investigated by single factor and multi factor methods. The impairment of parathyroid function was predicted combined with the level of PTH in the drainage fluid 1 day after operation.Results:After TT, serum PTH returned to normal value in most patients 1 month after operation. The proportion of PHP was 3.33% (5/150). Univariate analysis showed that bilateral central lymph node dissection, Hashimoto’s thyroiditis, tumor diameter ≥2 cm and intraoperative selective parathyroid autologous transplantation were risk factors for temporary hypoparathyroidism (THP). Multivariate analysis showed that BCND ( OR=0.322, P=0.001) , intraoperative selective parathyroid autograft ( OR=5.442, P=0.001) and tumor diameter ≥2 cm ( OR=2.247, P=0.003) were independent risk factors for THP. ROC curve was used to compare the predictive effect of postoperative serum and drainage PTH levels on postoperative PHP. The statistical results showed that the highest predictive effect of postoperative PHP was found on the first day of drainage PTH level within 1 week after operation (AUC 0.81) . 54 cases whose serum PTH was lower than normal value on the first day after operation were divided into 4 groups according to the level of PTH in drainage fluid from high to low. The results showed that the lower the level of PTH in drainage fluid, the greater the possibility of PHP ( P<0.05). Conclusions:Most of the patients with low PTH one month after operation develop PHP, while bilateral central lymph node dissection, intraoperative selective parathyroid transplantation, tumor diameter ≥2 cm are risk factors for THP after TT. If the serum PTH is lower than the normal value on the first day after operation, there is a possibility of PTH. The lower the PTH in the drainage fluid, the greater the possibility of PHP, which should be paid attention to in clinical practice.

Objective:To observe the changes of retinal blood flow density and thickness in the macular region of eyes with high myopia (HM) combined with peripapillary intrachoroidal cavitation (PICC).Methods:A cross-sectional study. From March 2019 to May 2021, 65 patients (65 eyes) diagnosed as PICC (HM+PICC group) in Eye Hospital, China Academy of Chinese Medical Sciences, sex-and age-matched 69 HM patients of 69 eyes (HM group) and 65 healthy people of 65 eyes (control group) were enrolled in this study. The optical coherence tomography angiography was used to scan macular areas in 3 mm×3 mm, and measure the macular fovea and optic disc on superior, inferior, nasal, temporal superficial capillary plexus (SCP) and deep capillary plexus (DCP) vessel density in the foveal and parafoveal region, and macular retinal ganglion cell complex (mGCC) thickness, full retinal thickness. One-way analysis of variance were used to test the difference of the index values among three groups, and then two groups were compared with Bonferroni test. A paired t-test was used to test the difference of the macular vessel density and thickness between the superior and inferior hemifield in three groups. Pearson partial regression analysis was used to calculate the correlations between them at same sites. Results:PICC was located most frequently at the inferior temporal disc border, followed by the inferior nasal region, superior temporal region, and superior nasal region in the HM+PICC group on 57(87.7%, 57/65), 25(38.5%, 25/65), 3(4.6%, 3/65) and 1(1.5%, 1/65 ) eye. There were significant differences in the global and regional full retinal thickness, mGCC thickness, SCP and DCP vessel density among 3 groups ( F=29.097, 51.929, 16.253, 6.135; P<0.001). The macular SCP and DCP vessel density except in the fovea, all regional macular full retinal thickness and mGCC thickness in the HM+PICC group were significantly lower than those in the normal group ( P<0.05). Compared to the HM group, the HM+PICC group had lower all regional mGCC thickness and SCP vessel density, as well as full retinal thickness in the inferior hemifield and DCP vessel density in the foveal region ( P<0.05). Macular vessel density and thickness in the inferior hemifield were significantly lower than those in the superior hemifield ( t=6.356, 11.693, 6.212, 2.936; P<0.01). Pearson partial regression analysis showed the SCP vessel density was positively correlated with corresponding mGCC thickness and full retinal thickness ( r=0.584, 0.534, 0.592, 0.496, 0.485, 0.517; P<0.001). However, there was no significant correlation between the DCP vascular density and mGCC thickness ( P>0.05), and only a weak positive correlation between the DCP vascular density and the full retinal thickness in the inferior hemifield ( r=0.319, P=0.014). However, no association with average and superior full retinal thickness ( r=0.066, 0.002, 0.125, 0.184, 0.016, 0.319; P>0.05). Conclusion:The macular SCP vessel density, mGCC thickness and the full retinal thickness in the inferior hemifield in PICC eyes are lower than those in the HM eyes, especially the mGCC thickness and SCP vessel density in the inferior hemifield, and there is a strong positive correlation between them.