The importance of corneal assessment in a glaucoma suspect – a review

Abstract

Glaucoma represents the main cause of irreversible blindness in the world and for this consideration, the interest in a quick and precise diagnosis and progression of the disease, prior to the appearance of irreversible damage, has been continuously rising. Glaucoma risk factors are already well known, but current studies reveal that it is necessary to make a proper analysis of the intraocular pressure (IOP) to obtain an accurate diagnosis, so we must take into consideration corneal properties that might affect IOP measurements. Starting from corneal geometrical properties represented by central corneal thickness (CCT) and continuing with biomechanical properties represented by corneal hysteresis (CH) and corneal resistance factor (CRF) we reviewed the value of investigating corneal properties in ocular hypertension (OH), primary open angle glaucoma (POAG) and normal tension glaucoma (NTG) patients. We can now say that CCT plays an important role in diagnosing glaucoma because it may mask the real value of the IOP and also, in setting the target for the IOP needed to stop disease progression. Also, CH is a factor that needs to be screened from the first consult of a glaucoma patient or suspect because it is correlated to the response to treatment, visual field (VF) and retinal nerve fiber layer (RNFL) progression and could anticipate the future evolution and patients prognosis. Both CCT and CH are factors that must be thought-about when we encounter a glaucoma suspect. CCT has a predictive role in OH and NTG patients, while CH has on the other hand a prognostic role in POAG, OH and NTG patients.

Corneal Biomechanical Assessment with Ultra-High-Speed Scheimpflug Imaging During Non-Contact Tonometry: A Prospective Review

“…In the last years, the role of corneal biomechanics in glaucoma setting has grown and both the CH and CRF from the ORA were proven to have a role both in diagnosis and prognosis, 125 , 126 with special attention in eyes with ocular hypertension or in normotension glaucoma patients. 16 …”

Sympathetic context of the disease - a new era in glaucoma management

“…Secondly, a low CCT acts as an independent risk factor in glaucoma. Furthermore, CCT should be considered when establishing an IOP treatment goal [ 15 ].…”

Modification of Corneal Biomechanics and Intraocular Pressure Following Non-Penetrating Deep Sclerectomy

“…Glaucoma represents one of the main underlying causes of irreversible blindness worldwide, with the most frequent type being primary open-angle glaucoma (POAG) [ 1 , 2 ]. The main risk factor for disease progression, and the only one we can influence, is intraocular pressure (IOP); for this reason, its detailed study, along with the corneal properties (both structural and biomechanical) that can affect its measurement, is essential [ 3 , 4 , 5 , 6 ].…”

“…Studies show that CH in subjects with glaucoma is significantly lower than in the general population [ 14 , 15 , 16 ]; this parameter has been associated with a greater defect in the optic disc. Further to this, a thinner layer of nerve fibers has been postulated as a risk factor for glaucoma progression, even in patients with well-controlled IOP measured by GAT [ 4 , 14 , 17 , 18 , 19 , 20 ]. In addition, the Ocular Hypertension Treatment Study (OHTS) concluded that CCT is a factor that can predict the evolution of ocular hypertension to POAG [ 21 ].…”