malar

The term 'malar' pertains to the zygomatic (cheek) bone and the overlying soft tissue of the cheek region. Clinically, it is most commonly referenced in the context of the 'malar rash' or 'butterfly rash' seen in systemic lupus erythematosus, which is an erythematous, raised rash over the malar eminences and bridge of the nose, characteristically sparing the nasolabial folds. This sparing helps distinguish it from other facial rashes like seborrheic dermatitis or rosacea. The malar rash is often photosensitive, worsening with sun exposure, and is one of the 11 classification criteria (SLICC/ACR) for SLE. Pathophysiology involves immune complex deposition and interface dermatitis at the dermal-epidermal junction, with UV light exposure triggering keratinocyte apoptosis and subsequent autoantigen exposure. 'Malar flush' is another related finding—a bluish-purple discoloration of the cheeks classically associated with mitral stenosis, caused by chronic low cardiac output and peripheral vasoconstriction leading to cutaneous vasodilation of capillaries with deoxygenated blood. The malar region is also relevant in facial fracture classification (e.g., malar/zygomatic complex fractures from trauma, causing flattening of the cheek and possible infraorbital nerve involvement).