PURPOSE: To investigate the anatomic and histologic changes present in midfacial ptosis. METHODS: Experimental study applying gross anatomic and histologic techniques to formalin-preserved and fresh-frozen cadaver heads with and without midfacial ptosis. High-resolution surface coil magnetic resonance imaging (MRI) was performed to obtain radiologic correlations. RESULTS: The orbitomalar ligament was further characterized by identification of a well-developed lateral component in the sub-superficial musculoaponeurotic plane; abnormalities of this important supporting structure were present in the subcutaneous plane in 8 of 10 specimens with midfacial ptosis. The zygomatic and masseteric cutaneous ligaments also were further characterized on a gross anatomic level, and histologic evidence of these two structures was produced. The subcutaneous components of the zygomatic and masseteric cutaneous ligaments were attenuated or not identifiable in 40% and 30% of specimens with midfacial ptosis, respectively. High-resolution surface coil MRI provided exquisite correlations of midfacial anatomy. CONCLUSIONS: The lateral component of the orbitomalar ligament provides major osteocutaneous midfacial support. Subcutaneous attenuation of the orbitomalar, masseteric cutaneous, and zygomatic ligaments was associated with midfacial ptosis.
PURPOSE: To investigate the anatomic and histologic changes present in midfacial ptosis. METHODS: Experimental study applying gross anatomic and histologic techniques to formalin-preserved and fresh-frozen cadaver heads with and without midfacial ptosis. High-resolution surface coil magnetic resonance imaging (MRI) was performed to obtain radiologic correlations. RESULTS: The orbitomalar ligament was further characterized by identification of a well-developed lateral component in the sub-superficial musculoaponeurotic plane; abnormalities of this important supporting structure were present in the subcutaneous plane in 8 of 10 specimens with midfacial ptosis. The zygomatic and masseteric cutaneous ligaments also were further characterized on a gross anatomic level, and histologic evidence of these two structures was produced. The subcutaneous components of the zygomatic and masseteric cutaneous ligaments were attenuated or not identifiable in 40% and 30% of specimens with midfacial ptosis, respectively. High-resolution surface coil MRI provided exquisite correlations of midfacial anatomy. CONCLUSIONS: The lateral component of the orbitomalar ligament provides major osteocutaneous midfacial support. Subcutaneous attenuation of the orbitomalar, masseteric cutaneous, and zygomatic ligaments was associated with midfacial ptosis.