Abstract and Introduction
Purpose of review: Patients with glaucoma with disease progression despite low or normal intraocular pressure (IOP) present special challenges to the treating clinician. Treatment goals may depend on whether patients have apparent low IOP with concurrent treatment or have low IOP at baseline without treatment. We review the diagnostic and therapeutic approaches to these patients.
Recent findings: Apparent progression at low IOP should start with confirmation of IOP, made easier by devices enabling patient home self-tonometry. Suspected visual field progression should be confirmed by repeat testing prior to advancement of therapy. Trabeculectomy remains the most effective surgical method of achieving long-term success, particularly when there is a low starting IOP. Drainage tube implantation or the use of novel micro-incisional non-bleb-forming procedures are less likely to be successful in achieving low IOP goals.
Summary: Diagnostic testing is important in confirming progressive glaucomatous disease at low IOP levels. The most effective way of slowing the progression of glaucoma in a patient with low IOP is to lower the IOP further, sometimes to single digit levels, which is most often achievable with trabeculectomy.
Patients with glaucoma with apparent progression despite low or normal intraocular pressure (IOP) engender several diagnostic and therapeutic dilemmas for the treating clinician, and the approach to their treatment remains controversial. Even more contentious is whether 'normal tension glaucoma' (NTG) should be a distinct disease entity, given that the relationship between IOP and glaucoma prevalence is continuous and without inflection point. Conveying to patients with lower than average IOP that they have a different disease than those with higher IOP is not necessarily based on sound evidence, especially as applanation IOP is affected by many factors, including central corneal thickness (CCT). Further, specific therapeutic approaches and goals for patients progressing at low IOP may depend on whether they had lower than average IOP at baseline or if they are progressing despite having had high IOP previously which was treated into the normal range. In this review, we discuss the clinical approach towards the patient with glaucoma with disease progression despite low or normal IOP.
Curr Opin Ophthalmol. 2020;31(2):107-113. © 2020 Lippincott Williams & Wilkins