An otherwise healthy 38-year-old woman presented to the emergency department with a 1-day history of generalized left-sided weakness. She had no other significant medical history and was taking no medications. The patient was overweight. Physical examination findings were unremarkable; the initial neurologic examination yielded no signs of organic disease. Dysthymia was diagnosed; a CT scan of the head was obtained. Drs Ali Ahmadizadeh and Juan Perez of Hoboken, NJ, report that the CT scan of the head suggested Gardner syndrome, an autosomal dominant familial polyposis of the large bowel that affects in 8000 persons.1 The average age at diagnosis is 25 years; average life expectancy for untreated patients is 45 years.2 The disease is characterized by various soft tissue tumors; colorectal adenomas; and multiple osteomas, particularly of the skull. Colorectal adenocarcinoma develops in all untreated patients. Recommend that family members of affected patients be screened for the condition. Prophylactic colectomy is advisable for all patients with confirmed disease. Multiple osteomas of the cranial vault (most typically, familial-type) is the likely diagnosis in patients who have osteomas of the skull with no other associated abnormalities. Some specialists believe that familial osteomas of the cranial vault is a variant of Gardner syndrome.3 The patient was referred to a gastroenterologist for colonoscopic evaluation. She is being monitored closely for extracolonic manifestations of Gardner syndrome, which may precede the detection of the colonic disease. The left-sided weakness resolved during her hospital stay; no neurologic deficit remained.