Squint angle

Squint Angle refers to the angular deviation between the visual axes of the eyes, a condition more formally known as Strabismus. This deviation can be either constant or intermittent and may affect one or both eyes. The squint angle is a critical measure in diagnosing and managing strabismus, as it quantifies the degree of misalignment between the eyes. Understanding and accurately measuring this angle is essential for effective treatment planning, including orthoptic exercises, glasses, or surgical interventions.

Causes and Types

Strabismus, and by extension the squint angle, can result from various causes, including genetic predispositions, muscle dysfunction, neurological disorders, or trauma. The condition is categorized into several types based on the direction of the eye misalignment:

• Esotropia: Inward deviation of the eye
• Exotropia: Outward deviation of the eye
• Hypertropia: Upward deviation of the eye
• Hypotropia: Downward deviation of the eye

Each type affects the squint angle differently, necessitating a tailored approach to measurement and treatment.

Measurement

The squint angle is measured in degrees using various techniques, with the Cover test and the use of a prism bar being among the most common. Precise measurement is crucial for determining the severity of strabismus and monitoring treatment progress. Advanced methods, such as Photorefraction and Video-oculography, offer more detailed analyses but are less commonly used due to their complexity and cost.

Treatment

Treatment aims to correct the squint angle, improve binocular vision, and prevent "lazy eye". Options include:

• Orthoptic exercises: Designed to strengthen the eye muscles and improve coordination
• Corrective glasses: Especially effective in cases where strabismus is caused by refractive errors
• Surgery: Involves adjusting the length or position of eye muscles to correct the squint angle

The choice of treatment depends on the squint angle's size, the strabismus type, and the patient's age and overall health.

Impact

An uncorrected squint angle can lead to significant visual impairment, including reduced depth perception and the development of amblyopia. Social and psychological impacts, particularly in children, can also arise from untreated strabismus, making early detection and treatment essential.