目的：研究原发性闭角型青光眼(PACG)患者一级亲属的眼前节结构特点。方法：选择2020-09/2022-10于南昌大学附属眼科医院就诊的40-60岁PACG一级亲属48例48眼作为观察组，同时纳入同年龄段、无青光眼及青光眼家族史的健康体检者40例40眼为对照组，按年龄分为低龄组(40-49岁)和高龄组(50-60岁)。所有研究对象均行超声生物显微镜(UBM)检查，使用camera measure测量软件进行测量，主要测量指标包括前房深度(ACD)、前房面积(ACA)、前房宽度(ACW)、眼前节深度(ASD)、房角开放距离(AOD500)、小梁虹膜夹角(TIA)、小梁虹膜间面积(TISA500)、晶状体拱高(LV)、虹膜曲率(IC)、虹膜厚度(IT500)、巩膜睫状突夹角(SCPA)及虹膜睫状突距离(ICPD)。比较两组各指标。结果：观察组ACD、ACA、AOD500、TISA500、TIA均比对照组小，LV、IC均比对照组大(均P<0.05)。高龄观察组ACD、ACA、AOD500、TISA500、TIA明显小于同龄对照组，LV、IC大于同龄对照组(均P<0.05)； 低龄观察组ACD、AOD500、TISA500、TIA明显小于同龄对照组，LV、IC显著大于同龄对照组(均P<0.05)。高龄观察组的ACD、ACA、AOD500、TISA500、TIA均显著小于低龄观察组，LV、IC显著大于低龄观察组(均P<0.05)。观察组与对照组ACD分布有差异(P<0.05)，其中中重度浅前房的占比约为对照组的10倍。相关性分析表明，TISA500与ACD、ACA呈正相关，与LV、IC呈负相关，TISA500主要受LV影响。IC与LV呈正相关，与ACD、ACA呈负相关。结论：正常眼轴的PACG一级亲属存在房角关闭的高风险性。PACG一级亲属的眼前节结构较正常人拥挤，晶状体前移可能是导致房角狭窄的始动影响因素。

AIM: To investigate the characteristics of anterior segment structure in first-degree relatives of patients with primary angle-closure glaucoma(PACG).METHODS: A total of 48 first-degree relatives of PACG patients aged 40-60 who were treated in the Affiliated Eye Hospital of Nanchang University from September 2020 to October 2022 were selected as the observation group. Additionally, 40 cases(40 eyes)of healthy individuals without glaucoma and family history of glaucoma at the same age group were collected as the control group. They were divided into younger group(40-49 years old)and elder group(50-60 years old). All subjects were examined with ultrasound biomicroscopy(UBM)and were measured using camera measure software. The parameters mainly included anterior chamber depth(ACD), anterior chamber area(ACA), anterior chamber width(ACW), anterior segment depth(ASD), angle open distance(AOD500), trabecular iris angle(TIA), trabecular iris area(TISA500), lens vault(LV), iris curve(IC), iris thickness(IT500), scleral ciliary process angle(SCPA), and iris ciliary process distance(ICPD).RESULTS: ACD, ACA, AOD500, TISA500 and TIA in the observation group were lower than those of the control group, and LV and IC were higher than those of the control group(all P<0.05). ACD, ACA, AOD500, TISA500, and TIA of the elder group were lower than those in the age-matched control group, while LV and IC were larger than those of the age-matched control group(all P<0.05). ACD, AOD500, TISA500, and TIA of the younger observation group were smaller than those of the age-matched control group, but LV and IC were significantly larger than those of the age-matched control group(all P<0.05). ACD, ACA, AOD500, TISA500 and TIA of the elder observation group were significantly lower than those of the younger observation group, and LV and IC were significantly larger than those of the younger observation group(all P<0.05). There was a difference in the distribution of ACD between the observation group and the control group(P<0.05), and the proportion of moderate to severe shallow anterior chambers was 10 times that of the control group. Correlation analysis showed that TISA500 was positively correlated with ACD and ACA, and negatively correlated with LV and IC, and TISA500 was mainly influenced by LV. IC had a positive correlation with LV and a negative correlation with ACD and ACA.CONCLUSION: First-degree relatives of PACG with normal axial length have a high risk of angle closure. The anterior segment structures of first-degree relatives of PACG are more crowded than normal individuals, and the lens forward shift may be the initial influencing factor for narrow angle.