Which of the following is NOT part of the sensory retina?

• A. Ganglion cell layer
• B. Outer plexiform layer
• C. Nerve fiber layer
• D. Bruch's membrane

Answer: (D)

The concept being tested is which structures form the neural (sensory) retina versus supporting tissues. The neural retina includes the layers that contain neurons and photoreceptors, such as the nerve fiber layer (axons of ganglion cells) and the ganglion cell layer (cell bodies of ganglion cells). The outer plexiform layer is where photoreceptors connect to bipolar and horizontal cells—also part of the sensory retina. Bruch's membrane, however, sits between the retinal pigment epithelium and the choroid; it is a boundary/structural support layer outside the neural retina, not part of the sensory retina itself. So Bruch's membrane is not part of the sensory retina. In OCT, you see Bruch's membrane as a boundary beneath the RPE, separate from the neurosensory layers.