abnormal retina inner plexiform layer morphology thin retina inner plexiform layer MP:0008513 thin retinal IPL reduced thickness of the retinal cell layer where bipolar and amacrine cell axons synapse with ganglion cell dendrites decreased retinal inner plexiform layer thickness thin retina IPL reduced retina inner plexiform layer thickness decreased retina inner plexiform layer thickness MPheno.ontology thin retinal inner plexiform layer reduced retinal inner plexiform layer thickness decreased thickness of the inner plexiform layer of retina