Читать книгу Imaging Techniques - Группа авторов - Страница 13

The ETDRS photography protocol is estimated to cover only 30% of the entire retinal surface. Lesions in the peripheral retina may not be fully evaluated even with ETDRS standard 7-field photographs. Ultrawide-field (UWF) retinal imaging systems using scanning laser ophthalmoscope technology combined with a large ellipsoidal mirror allows imaging of up to 90° of the retina in a single image without the need for pupil dilation. This is estimated to cover 82% of the entire retina surface (Fig. 4). Previous comparative studies have demonstrated a high degree of agreement between UWF photography and ETDRS film photographs. In addition, UWF enables more peripheral lesions to be detected, leading to an estimated reclassification of DR in 10% of eyes [7, 8]. UWF photography is also valuable in the follow-up of peripheral retinal pathologies, such as viral retinitis (Fig. 5), peripheral vascular diseases (Fig. 6), and retinal degeneration and tears.

Fig. 4. Ultrawide-field photograph of an eye with proliferative diabetic retinopathy and diabetic macular edema. Multiple areas of new vessels elsewhere can be seen (arrows). There are hard exudates and microaneurysms at the macula. Panretinal photocoagulation laser burns can be seen.