Which angle grade is classified as MOST narrow and likely to close according to the Van Herick technique?

The Van Herick technique is a method used to assess the anterior chamber angle by comparing the width of the angle structure to the width of the corneal depth. The angle grades classified using this technique range from Grade 1 to Grade 4, with Grade 1 indicating the narrowest angle.

Grade 1 is characterized by a very shallow angle, often described as less than 10 degrees. This narrow angle configuration is significant because it is more prone to closure, which can lead to angle-closure glaucoma. In contrast, the other grades (Grade 2, Grade 3, and Grade 4) indicate progressively wider angles, with Grade 4 being open and spacious. Therefore, Grade 1 is the classification that represents the highest risk for angle closure due to its narrowness. This understanding is critical in clinical practice to manage and monitor patients who may be at risk for angle-closure and related complications.