Diplocoria
| Diplocoria | |
|---|---|
| Other names | Double pupil; two pupils in one iris; a subset of polycoria (when exactly two) |
| A case of diplocoria | |
| Specialty | Ophthalmology |
| Symptoms | Glare, photophobia, reduced contrast, monocular diplopia |
| Complications | Amblyopia (in childhood), visual discomfort |
| Usual onset | Congenital (rare) or acquired |
| Causes | True accessory pupil with its own sphincter (very rare); more commonly, non-sphincter iris holes (pseudopolycoria) from surgery, trauma, or iris atrophy (e.g., ICE syndrome) |
| Diagnostic method | Slit-lamp examination, pharmacologic testing of pupillary reactivity, anterior-segment imaging |
| Treatment | Tinted/prosthetic contact lens; surgical pupilloplasty in selected cases |
| Frequency | Extremely rare (mostly case reports) |
Diplocoria is an ophthalmic term for the presence of two pupillary openings in a single iris ("double pupil"). In contemporary usage most reported "double pupils" represent pseudopolycoria: additional iris holes that lack their own sphincter muscle, whereas true diplocoria (a form of true polycoria) requires that each opening has a functional sphincter with synchronous constriction and dilation.[1][2] The term derives from Greek diplo- ("double") and korē ("pupil").[3]
Signs and symptoms
People with diplocoria or pseudopolycoria may experience glare, photophobia, ghosting, or monocular diplopia, due to multiple apertures disrupting the eye's optical system; reducing the effective pupil size can improve optical quality ("pinhole" effect).[4][5] In children, small reactive pupils and multiple apertures have been associated with intense miosis and amblyopia in case reports.[6]
Classification
Ophthalmic literature distinguishes:
- True diplocoria/true polycoria: each opening has a circumferential sphincter that reacts to light and pharmacologic agents; extremely rare.[1][7]
- Pseudopolycoria (false diplocoria): additional iris holes without sphincter muscle; these do not constrict independently and account for most "double pupil" appearances.[2]
Causes
True diplocoria is generally congenital and exceptionally uncommon. Apparent diplocoria is more often acquired pseudopolycoria from:
- iris procedures (e.g., surgical iridectomy/iridotomy, iris biopsy), trauma, or degeneration;[4]
- progressive iris atrophy in iridocorneal endothelial (ICE) syndrome, where tractional iris changes and stromal loss can produce iris holes (false pupils).[8][9]
Diagnosis
Slit-lamp examination documents the number, position, and shape of openings. In true diplocoria, both pupils constrict and dilate together to light or pharmacologic stimuli, indicating separate sphincters; in pseudopolycoria, only the primary pupil reacts.[1][2] Anterior-segment imaging and careful pharmacologic testing of the pupillary light reflex help differentiate true from false accessory pupils.[10]
Management
Treatment depends on symptoms and the underlying cause. Visual symptoms from pseudopolycoria may be reduced with prosthetic or tinted contact lenses that limit stray light or create a single functional aperture.[4] Selected cases of true diplocoria (true polycoria) have been treated surgically (e.g., pupilloplasty) to reconstruct a single round pupil.[11]
Epidemiology
Diplocoria in the strict, "true" sense is very rare and mainly documented in isolated case reports; most "double pupil" appearances are pseudopolycoria rather than true accessory pupils.[1][2]
See also
References
- ^ a b c d Islam, Niaz; Mehta, Jodhbir S.; Plant, Gordon T. (November 2007). "True polycoria or pseudo-polycoria?". Acta Ophthalmologica Scandinavica. 85 (7). Wiley: 805–806. doi:10.1111/j.1600-0420.2007.00985.x. PMID 17711542. Retrieved October 17, 2025.
- ^ a b c d Safi, A. (September 10, 2020). "Polycoria in a Young Girl". JAMA Ophthalmology. 138 (9). American Medical Association: e200656. doi:10.1001/jamaophthalmol.2020.0656. hdl:2078.1/251329. PMID 32910138. Retrieved October 17, 2025.
- ^ Venes, Donald (2025). "diplocoria". Taber's Medical Dictionary. F. A. Davis Company. Retrieved October 17, 2025.
- ^ a b c Sherman, Sarah W.; Khouri, Akrit S.; Campbell, Jeffrey P.; Say, Edwin A. T. (April 2021). "Relief of symptomatic pseudo-polycoria due to iris biopsy using a daily disposable prosthetic colored hydrogel lens". American Journal of Ophthalmology Case Reports. 22 101033. Elsevier. doi:10.1016/j.ajoc.2021.101033. PMC 8056339. PMID 33898861.
- ^ Manion, Garrett N. (February 28, 2024). "The Effect of Pupil Size on Visual Resolution - StatPearls". NCBI Bookshelf. StatPearls Publishing. Retrieved October 17, 2025.
- ^ Hofeldt, Gregory T.; Simon, John W. (October 2002). "Polycoria, Miosis, and Amblyopia". Journal of AAPOS. 6 (5). Elsevier: 328–329. doi:10.1067/mpa.2002.124649. PMID 12381993.
- ^ Jaffe, Norman S.; Knie, Paul (1952). "True polycoria". American Journal of Ophthalmology. 35 (2). Elsevier: 253–255. doi:10.1016/0002-9394(52)90856-8. PMID 14903014. Retrieved October 17, 2025.
- ^ Hollands, H. (September–October 2012). "Iridocorneal Endothelial Syndrome: Keys to Diagnosis and Management". Glaucoma Today. BMJ USA/Glaucoma Today. Retrieved October 17, 2025.
- ^ Chandran, P. (2017). "Glaucoma associated with iridocorneal endothelial syndrome in Indian population". PLOS ONE. 12 e0171884. Public Library of Science. doi:10.1371/journal.pone.0171884. PMC 5345787.
- ^ Belliveau, Arden P. (October 24, 2023). "Pupillary Light Reflex - StatPearls". NCBI Bookshelf. StatPearls Publishing. Retrieved October 17, 2025.
- ^ Bardak, Hüseyin; Ercalik, Neslihan Yalçın; Gunay, Mehmet; Bolac, R.; Bardak, Yusuf (November–December 2016). "Pupilloplasty in a patient with true polycoria: a case report". Arquivos Brasileiros de Oftalmologia. 79 (6). Sociedade Brasileira de Oftalmologia: 404–406. doi:10.5935/0004-2749.20160114. PMC 5344659. PMID 28099585.