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Published on: August 9, 2024
Clinical characteristics of pachychoroid-associated choroidal ossification
Yi Xuan1,2,3, Jie Hong1,2,3, Qing Chang1,2,3
1Eye Institute and Department of Ophthalmology, Eye & ENT Hospital, Fudan University, Shanghai, 20031, China.
Summary
Pachychoroid-associated choroidal ossification (PACO) is an acquired condition secondary to pachychoroid diseases, distinct from choroidal osteoma. Multimodal imaging reveals unique features, aiding in understanding its pathophysiology.
Area of Science:
- Ophthalmology
- Medical Imaging
- Pathophysiology
Background:
- Pachychoroid diseases are characterized by a thickened choroid with overlying abnormalities.
- Choroidal ossification, a rare condition, has not been well-characterized in the context of pachychoroid diseases.
- Pachychoroid-associated choroidal ossification (PACO) is a newly proposed entity requiring detailed investigation.
Purpose of the Study:
- To characterize the multimodal imaging features of pachychoroid-associated choroidal ossification (PACO).
- To differentiate PACO from other choroidal ossification entities like choroidal osteoma.
- To explore the potential pathophysiological mechanisms of PACO in eyes with pachychoroid diseases.
Main Methods:
- Retrospective case series of 12 eyes with PACO and 14 age-matched eyes with choroidal osteoma.
- Multimodal fundus imaging, including B-scan ultrasonography, indocyanine green angiography, and optical coherence angiography.
- Manual measurement of subfoveal choroidal thickness (SFCT) and maximum choroidal vessel diameter (MCVD) on OCT images.
Main Results:
- PACO lesions showed hyperechoic appearance with posterior shadowing on ultrasonography.
- Distinct features included tortuous vascular tufts (ICGA) and abnormal vasculature (OCTA).
- PACO was associated with chronic central serous chorioretinopathy or polypoidal choroidal vasculopathy, and showed increased SFCT and MCVD compared to osteoma.
Conclusions:
- PACO is an acquired choroidal ossification secondary to pachychoroid diseases, distinct from choroidal osteoma and fibrosis.
- Multimodal imaging findings enhance the understanding and recognition of PACO.
- Further research, including histological investigation, is warranted to fully elucidate PACO.
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