Nine-point photographic vitreous haze grading technique proves reliable

Am J Ophthalmol. 2011;152(2):170-176.

A nine-step logarithmic scale enabled predictable photographic grading of vitreous haze, a study found.

However, further study is needed to gauge the validity of using a vitreous haze scale in clinical trials, the study authors said.

"Photographic grading has the advantage of greater precision, log linearity based on optical blur, and the ability to train and test graders for reproducibility, but there are fundamental issues that remain unresolved," they said. "Additional study is needed to determine if the photographic vitreous haze scale can be used for haze grading in a clinical setting."

The retrospective study included 271 eyes of 142 patients with uveitis who participated in the Multicenter Uveitis Steroid Treatment trial. Patients were randomized to treatment with the Retisert intraocular implant (fluocinolone acetonide, Bausch + Lomb) or oral corticosteroids with immunosuppressive agents as needed.

Three examiners used the nine-step scale to evaluate baseline fundus photographs. Photographic haze scores were compared to clinical haze rankings.

Primary outcome measures were interobserver and intraobserver correlations for photographic haze grading, correlation between photographic and clinical vitreous haze scores, and assessment of clinical findings that influenced photographic haze scores.

Study results showed high interobserver and intraobserver intraclass correlations. Correlation coefficients ranged from 0.84 to 0.93. Data showed moderately strong correlation between photographic scores and clinical vitreous haze scores (P < .001).

Visual acuity of 20/50 or worse (P = .003), degrees of posterior synechiae (P < .001), lens abnormality (P = .023), posterior capsule obscuration (P = .001) and amount of anterior vitreous cells (P = .002) correlated strongly with photographic vitreous haze scores, the authors reported.