When evaluating the optic discs of glaucoma patients and suspects, optometrists have plenty of options. Heidelberg retinal tomography (HRT-3), optical coherence tomography (OCT) and scanning laser polarimetry (SLP) all do the job.
But those technologies can be expensive and not available at all centers in developing nations. And, most importantly, these modalities fail to work in opaque media, such as patients with dense cataracts, corneal opacities and vitreous hemorrhages. According to a newly published observational study, however, ultrasound can serve these patients with technology that is more common and affordable—especially in developing countries such as India (the site of the study), where patients with mature cataracts may also be suffering from undiagnosed glaucoma.
The research project, which ran from November 2009 to February 2011, looked at a total of 94 patients (182 eyes). Of them, 50 patients (95 eyes) had primary open-angle glaucoma and 44 patients (87 eyes) of similar age group were used as controls.
They found that sonographic imaging was able to procure a significantly superior vertical cup/disc ratio, cup area and cup area/disc area, compared with photographic methods. “We suggest ultrasound as a useful screening modality for glaucoma, though it cannot substitute clinical fundus evaluation,” the researchers noted.
|Chaurasia S, Garg R, Beri S, Pakhare A. Sonographic assessment of optic disc cupping and its diagnostic performance in glaucoma. J Glaucoma. [Epub ahead of print].|