Which of the following is the MOST common early pattern of a glaucomatous visual field defect?

The most common early pattern of a glaucomatous visual field defect is characterized by the presence of a para-central scotoma. This type of visual field loss typically occurs in the early stages of glaucoma as a result of damage to the retinal ganglion cells.

In the context of glaucoma, the initial effects on the visual field often manifest as small scotomas near the center of vision rather than more pronounced or extensive defects. The para-central scotoma can be subtle and may not be easily detected without careful testing.

As glaucoma progresses, more specific defects might develop, such as a superior arcuate defect or a nasal step, but these are generally seen in later stages. The enlarged blind spot can also occur in glaucoma but is not as characteristic or early an indicator of the disease as the para-central scotoma. Understanding this pattern is vital for early diagnosis and intervention, allowing for better management of the disease and preservation of vision.