Certified Ophthalmic Medical Technologist (COMT) Practice Exam

A patient's tight collar or breath-holding may cause what type of change in IOP?

1. Decrease

2. No change

3. Moderate increase

4. Increase

The correct answer is: Increase

Tight collars or breath-holding can lead to an increase in intraocular pressure (IOP) due to the physiological changes that occur in the body under these conditions. When a person holds their breath or experiences constriction around the neck, there is a resultant increase in intrathoracic pressure. This increased pressure can impede venous return and strain the cardiovascular system, leading to a rise in systemic blood pressure, which can subsequently affect the intraocular pressure. Increased intrathoracic pressure during breath-holding can also affect the pressure in the ocular vessels, contributing to a rise in IOP. As the blood flow dynamics change, the resistance within the eye can increase, further elevating IOP. Thus, the relationship between these physical states and IOP is understood to involve complex interactions between systemic circulation and ocular physiology, often culminating in an elevated IOP during episodes of breath-holding or physical constriction like a tight collar.