In a recent retrospective study, ultra-widefield (UWF) imaging showed relatively poor ability to identify horseshoe tears (HSTs), suggesting that clinicians should not rely on use of UWF technology on its own to rule out the presence of tears. Performance was particularly lacking within the superior quadrant of the retina.
Study design
This single-institution, retrospective analysis sought to evaluate UWF imaging sensitivity for detecting HSTs as compared to locating tears through scleral-depressed examination (SDE). A total of 123 patients (123 eyes) with HSTs seen on SDE who also underwent UWF imaging were included. The primary outcome was the number of HSTs detected on UWF imaging with a secondary outcome of tear location.
Outcomes
Of the 135 tears identified by SDE, only 51% (69 tears) were detected by foveal-centered UWF images. Sensitivity varied by location, with UWF imaging identifying 17% (7/41), 32% (8/25), 50% (7/14), and 86% (47/55) tears in the superior, inferior, nasal, and temporal quadrants, respectively.
Limitations
Some limitations of this study include its retrospective nature as well as its focus on foveal-centered imaging. If decentered images were included, it is possible that more tears would have been found by UWF imaging. On the other hand, images were obtained by skilled ophthalmic photographers who are often not the operators in most offices and, therefore, image quality outside of this study would likely be less optimal, leading to a lower tear-detection sensitivity. In addition, UWF images are often used in telemedicine as well as in optometry offices to spare the patient from dilation. Lack of dilation certainly leads to poorer imaging capabilities and a diminished view of the retinal periphery. Finally, all patients with images in this study were known to have tears. This likely influenced the sensitivity of image grading.
Clinical significance
Nearly half of HSTs were missed by UWF imaging, demonstrating that UWF imaging has a low sensitivity for detecting HSTs, with especially poor sensitivity seen in the superior regions of the retina. Therefore, it is crucial that UWF imaging is not relied upon alone for the detection of HSTs. The false reassurance of a negative UWF image in a patient with new flashes and floaters could lead to a missed tear, delayed referral, and potential loss of vision.
Financial Disclosures: Dr. Lisa Schocket discloses no financial relationships.