Ultra-Widefield Fundus Photography Combined with Traditional Imaging Identifies More Advanced Diabetic Retinopathy Cases
核心洞察
Ultra-widefield (UWF) imaging combined with ETDRS 7-field photography detects more cases of advanced diabetic retinopathy (搜索) than standard imaging alone, according to a prospective study of 147 eyes.
Extended imaging integrating both central and peripheral retina showed near-perfect agreement with the ETDRS reference standard while consistently identifying more severe disease.
Peripheral-only grading was found to underestimate disease burden; researchers recommend extended widefield imaging as the new standard for DR severity classification in clinical trials and routine practice.
A prospective study from Portugal has demonstrated that combining ultra-widefield (UWF) fundus photography with traditional ETDRS 7-field imaging identifies significantly more eyes with advanced diabetic retinopathy (搜索) (DR), supporting a paradigm shift toward extended widefield imaging as the new standard for disease severity classification.
The findings, published in the British Journal of Ophthalmology, compared DR severity grading across three imaging modalities: ETDRS 7-field color fundus photography, Clarus 500 two-field UWF, and Optos (搜索) California single-field UWF in 81 participants (147 eyes) with type 2 diabetes (搜索) and ETDRS-Diabetic Retinopathy (搜索) Severity Scale levels 35 to 47.
Both UWF systems showed strong agreement with ETDRS 7-field color fundus photography in DR severity grading. However, the study revealed that peripheral lesions were frequent and, when combined with ETDRS fields, identified eyes with more advanced disease that would otherwise have been missed.
"Adopting extended widefield imaging as the new standard will modernize trial endpoints, streamline workflows in clinical practice and ensure that severity classification better reflects the full extent of disease," the study authors wrote.
Peripheral-Only Grading Falls Short
A critical finding was that analysis of peripheral fields alone does not provide additional severity information and may in fact underestimate disease burden. In contrast, extended imaging that integrates both central and peripheral retina yielded the most reliable classification, showing near-perfect agreement with the ETDRS reference while consistently detecting more severe disease.
The tendency toward higher severity grading with UWF imaging, particularly with the Clarus system, appeared to be driven not only by the wider field of view but also by enhanced lesion detection within the ETDRS-equivalent region. Improved visualization of features such as hemorrhages and intraretinal microvascular abnormalities may contribute to higher ETDRS scores compared with standard fundus photography.
"From a clinical perspective, these results support the use of extended UWF imaging as a practical and reliable approach to DR severity grading in clinical trials and routine practice," the researchers emphasized. "Extended montages capture peripheral disease without sacrificing alignment with the ETDRS standard, offering a feasible pathway toward modernization of DR classification. Conversely, peripheral-only grading should not be used for severity staging, as it may underestimate risk."
Implications for Clinical Practice
The traditional ETDRS 7-field protocol, long regarded as the gold standard for DR grading, covers only approximately 35% of the retinal surface, leaving large peripheral areas undocumented. UWF imaging systems, including Clarus (Zeiss (搜索)) and Optos (搜索), provide up to 200° retinal coverage with fewer acquisitions, overcoming this fundamental limitation.
The study employed a methodology in which ETDRS grids were superimposed on UWF images, allowing direct evaluation of agreement in DRSS grading while also assessing the contribution of peripheral lesions beyond the ETDRS fields to disease severity and progression.
These findings carry significant implications for both clinical trial design and routine ophthalmology practice, suggesting that extended UWF imaging can modernize DR classification without sacrificing alignment with the established ETDRS standard that has guided the field for decades.