Table 2.

Summary of findings on post-mortem examination in five cats with hyaline degeneration

	Macroscopic findings	Microscopic findings: brain	Microscopic findings: spinal cord
Cat 1	Hemorrhage – ventral brainstem/cervical SC	AD, HyD (BA), thrombosis, WM degeneration (caudal medulla)	AD (VSA) C3-C5, thrombosis, ventral funiculus WM degeneration
Cat 2	Hemorrhage – ventral brainstem/cervical SC (Figure 3)	HyD (meninges), thrombosis (BA branch), leptomeningeal fibrosis, acute, chronic hemorrhage (medulla) (Figure 5c). WM degeneration cerebellar peduncle hemorrhage	Cranial cervical SC, bilateral WM/GM necrosis
Cat 3	Red nodule (vascular ectasia [aneurysm]) – ventral C2	HyD (meninges), mixed perivascular/vascular inflammation	AD (VSA), chronic perivascular hemorrhage, GM degeneration, hemorrhage, gliosis, HyD (C3)
Cat 4	Red nodules (vascular ectasia [aneurysm]) – ventral C3–C5, L3–L4, medulla (Figure 4)	AD, HyD (BA branch), compression, midline shift, regional WM degeneration, necrosis, chromatolysis	AD, HyD (VSA) C3–C5, L3, L4, thrombosis, compression (Figures 5a,b), WM degeneration, occasional necrosis, chronic hemorrhage, inflammation
Cat 5	Red nodules (vascular ectasia [aneurysm]) – C7–T1, L3	HyD (BA branches), mineralization, meningeal chronic inflammation and hemorrhage, focal cerebellar necrosis	AD, HyD (VSA) C7–T1, L3, thrombosis, compression, ventral funiculi WM degeneration, gliosis, chromatolysis

SC = spinal cord; AD = aneurysmal dilation; HyD = hyaline degeneration; BA = basilar artery; WM = white matter; VSA = ventral spinal artery; GM = gray matter