MMPH is not typically associated with physiologic or prognostic consequences, but one case of respiratory failure due to MMPH has been reported. Ventilation-perfusion scans
In one study ventilation-perfusion scans were abnormal in 34 of 35 LAM patients. The most common abnormality was nonspecific diffuse heterogeneity, usually grossly matched. These authors also described an “unusual,” “speckling pattern” on the perfusion images in 74% of patients, consisting of “small, often peripheral collections of radioisotope.”

Positron emission tomography
LAM and AML lesions do not typically exhibit increased uptake of 18F-fluorodeoxyglucose on positron emission tomography (PET) scanning. Other neoplasms (or sources of inflammation) should therefore be considered in known or suspected LAM cases in which FDG-PET results are positive. Abdominal imaging
Abnormalities on abdominal imaging, such as renal AML and enlarged lymphatic structures, are also common in LAM. Fat density within a renal mass is pathognomonic of AMLs. AMLs are more prevalent and more frequently bilateral and large in patients with TSC-LAM than in patients with S-LAM. AML size correlates with the prevalence of pulmonary cysts in patients with TSC. One study CT imaged 256 patients with S-LAM and 67 with TSC-LAM. Renal AMLs were present in 32% of patients with S-LAM and 93% of patients with TSC-LAM. Hepatic AMLs were present in 2% of patients with S-LAM and 33% of patients with TSC-LAM. Ascites was uncommon, seen in fewer than 10% of patients with LAM. Abdominal lymphangiomatosis, often containing both cystic and solid components, were seen in 29% of patients with S-LAM and 9% of patients with TSC-LAM.
Thoracic duct ligation can be considered, but since thoracic effusions sometimes originate from ascites that are siphoned into the chest by the bellows action of the thorax, it is important to rule out an abdominal source before considering this option. Pleural symphysis may be required to prevent nutritional and lymphocyte deficiencies that can result from repeated taps or persistent drainage. Chemical pleurodesis is generally an effective therapy for chylothorax, as is mechanical abrasion and talc poudrage. Angiomyolipoma
Renal angiomyolipomas (AMLs) may require embolization or cauterization for control of bleeding, a complication that is thought to be more common when tumor diameter exceeds 4 cm. The extent of aneurysmal change may determine bleeding risk. Serial abdominal imaging should be performed to assess AML size at 6- to 12-month intervals, at least until trends in growth are clear. Nephron sparing partial resections may be considered for very large tumors. Nephrectomy is sometimes required for tumors with intravascular extension or other reasons, but is rarely the approach of choice for AMLs that can be managed by less invasive means. Everolimus is approved by the U.S. Food and Drug Administration (FDA) for AML treatment. Lymphangioleiomyoma
Lymphangioleiomyomatoses are fluid-filled hypodense structures present in the retroperitoneal regions of the abdomen and pelvis in about 30% of LAM patients. They generally do not require intervention. Biopsy or resection can lead to prolonged leakage. mTOR inhibitors are effective at shrinking the size of lymphangioleiomyomatosis, and can lead to total resolution. Management-other
Estrogen-containing medications can exacerbate LAM and are contraindicated.