Optic disc drusen in patients diagnosed with normal tension glaucoma.

PURPOSE: To investigate the prevalence of optic disc drusen (ODD) and optic nerve head (ONH) morphology in patients diagnosed with normal tension glaucoma (NTG). METHODS: In this prospective cross-sectional study, we included patients diagnosed with NTG from two glaucoma units. In both eyes, dense enhanced depth imaging optical coherence tomography volume scans of the ONH by means of standardized scanning guidelines were performed to examine for presence of ODD, and radial ONH scans were used for investigating parameters such as scleral canal diameter, cup/disc ratio and cup depth. RESULTS: We found ODD in 7 (3.6%) of 195 eyes, in 6 (6.1%) out of 98 patients diagnosed with NTG. The ODD were not ophthalmoscopically visible in five out of six patients. Eyes with ODD had lower cup/disc ratio, 0.44 ± 0.4 (p = 0.040), and less-prominent cup depth, 236.6 ± 204.4 µm (p = 0.041) compared to eyes without ODD, 0.81 ± 0.2 and 437.8 ± 139.1 µm, respectively. We found no significant difference in scleral canal diameter between the eyes without (1602.8 ± 193 µm) and those with ODD (1492 ± 123.4 µm, p = 0.057). CONCLUSION: The prevalence of ODD in patients diagnosed with NTG is substantially higher than in the background population. A low cup/disc ratio correlates with ODD presence. Therefore, due to the challenges associated with NTG diagnosis, we recommend examining the deep layers of the ONH in NTG patients with a cup/disc ratio lower than 0.5 to avoid misdiagnosing ODD as NTG.

Girl Power in Glaucoma: The Role of Estrogen in Primary Open Angle Glaucoma.

Estrogen is essential in maintaining various physiological features in women, and a decline in estrogen levels are known to give rise to numerous unfortunate symptoms associated with menopause. To alleviate these symptoms hormone replacement therapy with estrogen is often used, and has been shown to be fruitful in improving quality of life in women suffering from postmenopausal discomforts. An often forgotten condition associated with menopause is the optic nerve disorder, glaucoma. Thus, estrogen may also have an impact in maintaining the retinal ganglion cells (RGCs), which make up the optic nerve, thereby preventing glaucomatous neurodegeneration. This review aims to provide an overview of possible associations of estrogen and the glaucoma subtype, primary open-angle glaucoma (POAG), by evaluating the current literature through a PubMed-based literature search. Multiple in vitro and in vivo studies of RGC protection, as well as clinical and epidemiological data concerning the well-defined retinal neurodegenerative disorder POAG have been reviewed. Over all, deficiencies in retinal estrogen may potentially instigate RGC loss, visual disability, and eventual blindness. Estrogen replacement therapy may therefore be a beneficial future treatment. However, more studies are needed to confirm the relevance of estrogen in glaucoma prevention.