Which probe orientation is ideal for demonstrating the insertion of membranes into the optic disc?

The ideal probe orientation for demonstrating the insertion of membranes into the optic disc is a longitudinal scan. This scanning technique provides a clear view of the optic nerve and its surrounding structures along the axis of the eye. When performing a longitudinal scan, the sonographer can visualize the posterior pole, allowing for assessment of the optic disc and any associated membranes or pathologies.

A longitudinal scan captures a cross-section of the optic nerve head, which is crucial for identifying structures like epiretinal membranes or other abnormalities that may be present at the optic disc. The orientation aligns with the anatomical features of the disc, ensuring a detailed representation of the membranes' insertion points.

Other scan types, such as transverse, radial, or axial scans, may not provide the same level of clarity or detail in this specific area. While radial scans can also provide good views of the optic disc, they may not focus on the insertion points as effectively as a longitudinal scan. Therefore, selecting the longitudinal orientation enables optimal visualization for diagnosing conditions related to the optic disc and its membranes.