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Updated: Jan 27, 2026
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Large-Scale Purification of Porcine or Bovine Photoreceptor Outer Segments for Phagocytosis Assays on Retinal Pigment Epithelial Cells
Published on: December 12, 2014
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Evaluation of photoreceptor outer segment length in hydroxychloroquine users.
Akin Cakir1, Şeyma Gulcenur Ozturan2, Dilan Yildiz2
1Department of Ophthalmology, University of Health Sciences, Okmeydani Training and Research Hospital, Istanbul, Turkey. dracakir@gmail.com.
Eye (London, England)
|April 2, 2019
Summary
Long-term hydroxychloroquine (HCQ) users showed increased photoreceptor outer segment (PROS) length compared to controls. This finding in HCQ users may indicate early retinal pigment epithelium toxicity before retinopathy develops.
Area of Science:
- Ophthalmology
- Retinal Imaging
- Pharmacology
Background:
- Hydroxychloroquine (HCQ) is widely used for autoimmune conditions.
- HCQ retinopathy is a known complication, but early detection is crucial.
- Photoreceptor outer segment (PROS) length changes may serve as an early indicator.
Purpose of the Study:
- To evaluate PROS length in patients using HCQ before retinopathy onset.
- To compare PROS length between long-term HCQ users, short-term HCQ users, and healthy controls.
Main Methods:
- Prospective, single-center, comparative study.
- 44 patients using HCQ ≥5 years, 30 using HCQ <5 years, and 45 controls.
- Ophthalmologic examination, SD-OCT imaging, and automated visual field testing.
Main Results:
- Long-term HCQ users (≥5 years) had significantly greater PROS length than controls at all measurement points.
- Parafoveal PROS length was significantly greater in long-term users compared to short-term users.
- No significant difference in PROS length was observed between short-term users and controls.
Conclusions:
- Increased PROS length was observed in patients using HCQ for ≥5 years.
- This finding may suggest potential retinal pigment epithelium toxicity preceding overt retinopathy.
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