Clemons Traci E, Gillies Marc C, Chew Emily Y, Bird Alan C, Peto Tunde, Figueroa Maria J, Harrington Molly W
The EMMES Corporation, Rockville, MD 20850, USA.
Ophthalmic Epidemiol. 2010 Jan-Feb;17(1):66-73. doi: 10.3109/09286580903450361.
To describe the baseline characteristics of a large international cohort of patients with macular telangiectasia type 2 (MacTel Type 2) in anticipation of a longitudinal natural history study to evaluate structural and functional changes, identify potential risk factors and related outcomes.
Images including fundus photographs, fluorescein angiograms, optical coherence tomography and fundus autofluorescence were collected. A grading system for MacTel type 2 was developed by the central reading center to evaluate lesion characteristics. Relationships between lesion characteristics and visual acuity were evaluated.
A total of 310 participants have been enrolled in the study. The mean time since diagnosis was 3 years (range 0 to 25 years). The mean age at the baseline examination was 61 +/- 9 years. The mean visual acuity in the better eye was approximately 20/32 Snellen equivalents and approximately 20/50 in the worse eye. The visual acuity in the better eye of half of the participants was 20/32 or better. We found some relationships between visual acuity and lesions characteristic of MacTel Type 2.
This is the first large-scale study of patients with MacTel Type 2. More than half of the patients had 20/32 or better vision in their better eye, which is a sign that decreased function in these participants may not be reflected in central visual acuity. These findings highlight the limitation of using visual acuity measurements as a measure of function and as an outcome measure in potential clinical trials in patients with MacTel Type 2.
为了开展一项纵向自然史研究，以评估黄斑毛细血管扩张症2型（MacTel 2型）患者的结构和功能变化、识别潜在风险因素及相关结局，本研究描述了一个大型国际队列患者的基线特征。
收集了包括眼底照片、荧光素血管造影、光学相干断层扫描和眼底自发荧光在内的图像。中央阅片中心开发了一种MacTel 2型分级系统，以评估病变特征。评估了病变特征与视力之间的关系。
共有310名参与者纳入本研究。自诊断以来的平均时间为3年（范围0至25年）。基线检查时的平均年龄为61±9岁。较好眼的平均视力约为20/32 Snellen等效视力，较差眼约为20/50。一半参与者较好眼的视力为20/32或更好。我们发现了MacTel 2型的视力与病变特征之间的一些关系。
这是首次对MacTel 2型患者进行的大规模研究。超过一半的患者较好眼的视力为20/32或更好，这表明这些参与者的功能下降可能未在中心视力中得到体现。这些发现凸显了在MacTel 2型患者潜在临床试验中，将视力测量用作功能指标和结局指标的局限性。
