Lymphangioleiomyomatosis: CT of diurnal variation of lymphangioleiomyomas

PURPOSE: To evaluate the imaging and clinical features of lymphangioleiomyo mas and to describe the phenomenon of diurnal variation in the size of lymp hangioleiomyomas in patients with lymphangioleiomyomatosis. MATERIALS AND METHODS: One hundred twenty-eight patients with lymphangiolei omyomatosis underwent chest and abdominopelvic computed tomography (CT). Th irteen patients underwent CT in the morning and afternoon of the same day t o assess diurnal variation in lymphangioleiomyoma size. RESULTS: Twenty-seven of 128 patients (21%) had 54 lymphangioleiomyomas. Th e vast majority (96%) of these masses contained material of low attenuation at CT. Associated CT findings included enlarged abdominal lymph nodes, ple ural effusions, ascites, and dilatation of the thoracic duct. The prevalenc e of lymphangioleiomyomas was 15% in patients who had mild pulmonary diseas e, 19% in patients who had moderate disease, and 26% in patients who had se vere disease. Diurnal variation in size of masses was demonstrated in 12 of 13 patients. Seven of the 27 patients who had masses underwent biopsy; all seven were confirmed to have lymphangioleiomyomas. The most common symptom s associated with lymphangioleiomyomas were bloating, abdominal pain, and e dema of the lower extremities. The majority of the patients reported worsen ing of symptoms as the day progressed. CONCLUSION: Lymphangioleiomyomas are common in patients with lymphangioleio myomatosis. Diurnal variation in size may explain worsening of symptoms dur ing the day.