Patterns of Visual Field Loss in Glaucoma

The hallmark defect of glaucoma is the nerve fiber bundle defect that results from damage at the optic nerve head. The pattern of nerve fibers in the retinal area served by the damaged nerve fiber bundle will correspond to the specific defect. The common names for the classic visual field defects are derived from their appearance as plotted on a kinetic visual field chart. In static perimetry, however, the sample points are in a grid pattern, and the representation of visual field defects on a static perimetry chart generally lacks the smooth contours suggested by such terms as arcuate.

Figure 6-7 High false-positive rate. The top visual field contains characteristic “white scotomas,” which represent areas of impossibly high retinal sensitivity. On the return visit 3 weeks later, the patient was carefully instructed to respond only when she saw the light, resulting in the bottom visual field, which shows good reliability and demonstrates the patient’s dense superior visual field loss (Humphrey 30-2 program).

Glaucomatous visual field defects include the following:

• arcuate or Bjerrum scotoma (Fig 8-6)

• nasal step (Fig 9-6)

• paracentral scotoma (Fig 10-6)

• altitudinal defect (Fig 11-6)

• generalized depression (rare in glaucoma in the absence of localized loss)

• temporal wedge (rare)

Figure 6-8 An arcuate scotoma occurs in the area 10°–20° from fixation. Glaucomatous damage to a nerve fiber bundle containing axons from both the inferonasal and inferotemporal retina resulted in the arcuate defect shown. The scotoma often begins as a single area of relative loss, which then becomes larger, deeper, and multifocal. In its full form, an arcuate scotoma arches from the blind spot and ends at the nasal raphe, becoming wider and closer to fixation on the nasal side (Humphrey 24-2 program).

(Visual field courtesy of G.A. Cioffi, MD.)

The superior and inferior poles of the optic nerve are most susceptible to glaucomatous damage. However, damage to small, scattered bundles of optic nerve axons commonly produces a generalized decrease in sensitivity, which is harder to recognize than focal defects. Combinations of superior and inferior visual field loss, such as double arcuate scotomas, may occur, resulting in profound peripheral vision loss. Typically, the central island of vision and the inferotemporal visual field are retained until late in the course of glaucomatous optic nerve damage (see Fig 2-6).

• Heijl A, Bengtsson B, Patella VM. Effective Perimetry. 4th ed. Carl Zeiss Meditec AG; 2012.

Figure 6-9 A nasal step is a relative depression of 1 horizontal hemifield compared with the other. Damage to superior nerve fibers serving the superotemporal retina beyond the paracentral area resulted in this nasal step. In kinetic perimetry, the nasal step is defined as a discontinuity or depression in 1 or more nasal isopters near the horizontal raphe (Humphrey 24-2 program).

(Visual field courtesy of G.A. Cioffi, MD.)

Excerpted from BCSC 2020-2021 series: Section 10 - Glaucoma. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.