Trichorhinophalangeal syndrome (TRPS) comprises TRPS I (caused by a heterozygous pathogenic variant in TRPS1) and TRPS II (caused by contiguous gene deletion of TRPS1, RAD21, and EXT1). Both types of TRPS are characterized by distinctive facial features; ectodermal features (fine, sparse, depigmented, and slow growing hair; dystrophic nails; and small breasts); and skeletal findings (short stature; short feet; brachydactyly with ulnar or radial deviation of the fingers; and early, marked hip dysplasia). TRPS II is characterized by multiple osteochondromas (typically first observed clinically on the scapulae and around the elbows and knees between ages 1 month and 6 years) and an increased risk of mild-to-moderate intellectual disability.

Rupture of an intracranial aneurysm (IA), an outpouching or sac-like widening of a cerebral artery, leads to a subarachnoid hemorrhage (SAH), a sudden-onset disease that can lead to severe disability and death. Several risk factors such as smoking, hypertension, and excessive alcohol intake are associated with subarachnoid hemorrhage (summary by Krischek and Inoue, 2006).