It displaces the eye’s pupil from its usual central position.
Usually, the pupil is located about 0.5 mm inferonasal from the center of the iris.
Minor deviations up to 1.0mm are generally cosmetically insignificant and should probably not be considered abnormal.
In this rare anomaly, visual acuity may be good, even with eccentric pupils, if it is not associated with other congenital anomalies or poor vision; you need peace of mind.
Most cases do not require intervention or respond well to the simple fibrous chain lysis characteristic of the condition.
Idiopathic traction correctness
It is an isolated unilateral pupillary congenital anomaly. It responds well to the simple fibrous chain lysis in this condition.
Types of corectopia
When corectopia is present from birth (i.e., “congenital”), the displacement of the pupil is usually toward the nose (medial).
When corectopia is acquired due to trauma or scarring of the iris (accidental or surgical) or ocular causes such as high myopia, ectopia lentis, coloboma iridis, Axenfeld-Reiger anomaly, persistent pupillary membrane, and hyperplastic pupillary membrane).
Symptoms of corectopia
Corectopia is identified by the displacement of the pupil from its center and is commonly deviated nasal. It is generally bilateral and symmetrical, and the direction of travel is up and out.
Unilateral cases are rare. Ectopia lentis is a common accompaniment, and other uveal tissue abnormalities can coexist.
This condition has a hereditary tendency as a recessive characteristic. Some of the reported cases have shown evidence of intrauterine inflammation.
Causes of corectopia
In a case series of five children with congenital corectopia without associated ocular cause, three had chromosomal abnormalities, one a probable prenatal diplegia, and a bilateral perisylvian dysplasia with vermian and midbrain hypoplasia.
The cause of corectopia can be congenital or acquired. The latter is usually associated with midbrain lesions and coma, and the poor prognosis is almost universal.
Bilateral congenital corectopia is an ophthalmic sign that deserves chromosomal analysis and neurodevelopmental evaluation.
Diseases associated with corectopia
It can be associated with high myopia or ectopia lentis, among other conditions. Hypoplasia of the sectoral iris or other colobomatous lesions can lead to corectopia, and an isolated noncolombotic autosomal dominant corectopia has also been reported.
More commonly, however, corectopia is associated with lens subluxation, and this combination is called ectopia lentis et pupillae. The condition is almost always bilateral, with the pupils and lenses displaced in opposite directions.
The pupils can be oval or slit-shaped and often poorly dilated. Iris transillumination can occur, and microspherophakia has been reported.
Progressive corectopia can be associated with the Axenfeld-Rieger spectrum and iridocorneal endothelial syndrome (ICE). Visual acuity can be good, even with eccentric pupils.
Lipoid proteinosis (Urbach-Wiethe disease) is a rare autosomal recessive disorder. Cases of association of bilateral corectopia with this condition have been reported.
Diagnosis of corectopia
If your child has a suspected unilateral pupillary abnormality, it is suggested that you consult an ophthalmologist, who will most likely rule out bilateral corectopia first.
Moreover, of course, it will assess the general condition of the eyes. Only an ophthalmologist will be the best place to advise you on other administration of your child.
The differential diagnosis of corectopia includes iridocorneal endothelial syndrome, Axenfeld-Rieger syndrome, trauma, sectoral iris hypoplasia, or other colobomatous lesions.
Treatment for corectopia
Management depends on the cause. It can be medical, surgical, or both. Bilateral congenital corectopia is a sign that deserves chromosomal analysis and neurodevelopmental evaluation.
In some cases, medical or surgical intervention may be indicated for treating corectopia.
Corectopia is an eccentric location of the pupil. The displacement follows an intracapsular cataract extraction.
Peripheral iridectomy at 12:30 does not prevent the occurrence of this rare but well-known complication of cataract surgery.
The peak of the distorted pupil points to the area of angle pathology. Gonioscopy reveals anterior synechia in that position. Fortunately, despite incarceration at the healed limbal incision, an actual prolapse of the iris does not develop.
Unilateral corectopia case
A 50-year-old laborer attended the outpatient department with a history and clinical features of upper respiratory infection.
There was no history of visual symptoms. There was no significant family history of congenital eye diseases. His vital signs and general and system examinations were typical.
However, examination of his left eye showed a small eccentrically placed pupil with a reduced papillary diameter. The right pupil was of average size and reaction.
Extraocular movements were regular and complete bilaterally. His visual acuity and optic fundus were normal. An ophthalmic consultation was performed, which demonstrated a standard visual field and visual acuity. He was diagnosed with unilateral idiopathic tractional corectopia.
Congenital abnormalities of pupil position and shape are rare. Average pupil sizes in adults range from 2 to 4 mm in diameter in bright light to 4-8 mm in the dark and are generally of equal size.
The pupils have typically located about 0.5 mm inferonasal from the center of the iris. Corectopia refers to the displacement of the pupil, which is usually around 0.5 mm inferonasally from the center of the iris.
Minor deviations of up to 1mm are generally cosmetically insignificant and should not be considered abnormal. In this case, the abnormal position of the pupil is caused by a fibrous structure that ties the pupillary margin of the iris to the peripheral cornea.
Idiopathic tractional corectopia is an isolated unilateral pupillary congenital anomaly with a highly characteristic appearance.
Case of bilateral corectopia
In a patient with a dural arteriovenous fistula resulting in a prominent basal vein of Rosenthal involving the midbrain.
A 37-year-old man presented to our neuro-ophthalmology clinic with complaints of light sensitivity and large pupils bilaterally for six months.
A year ago, he experienced pulsatile tinnitus and later began to misspell words on the computer.
On examination, the corrected visual acuity of the right and left eyes was 20/20 and 20/20, respectively. Color vision and sense of brightness were normal.
The pupils revealed anisocoria, more significant in the bright (outer diameter 5 mm, OS 7 mm) than in the dark (outer diameter 6 mm, OS 7 mm).
The pupillary reaction was slow. The relative afferent pupillary defect was absent.
Slit-lamp examination revealed corectopia in both pupils, noting a peak observed at the 8 o’clock position of the right pupil and in the 4 and 8 o’clock region of the left pupil.
Slight vermiform movements of both pupils were present, worse in the left eye than in the right, and the patellar reflexes were moderately diminished bilaterally.
These characteristics were suggestive of Adie’s pupil, so the cholinergic supersensitivity test for Adie’s pupil was performed with dilute pilocarpine (0.1%).
No pupillary changes were observed even after the second application of 0.1% pilocarpine after 40 minutes. The presence of corectopia justified the exclusion of any midbrain lesion.
An MRI of the brain was requested and revealed some asymmetric prominence of the left basal vein of Rosenthal.
In addition, an increased flow artifact was observed medial to the left cavernous portion of the internal carotid artery, suggesting an indirect carotid-cavernous fistula.
A subsequent study with diagnostic cerebral angiography and later computed tomography angiography of the brain confirmed a durable sphenoidal Cognard type 4 arteriovenous fistula of the left temporal pole located along the anterior aspect of the left middle cranial fossa.
Given the draining ectatic cortical veins, it was considered a severe injury with the potential to rupture and cause a posterior intracerebral hemorrhage.
Endovascular embolization of the arteriovenous fistula was attempted, and only partial embolization was achieved.
The patient was referred to the neurosurgery department and, after two months, underwent a craniotomy and successful ligation of the dural arteriovenous fistula, confirmed by diagnostic cerebral angiography the following day.
After three months, the corrected visual acuity was 20/25 and 20/20 on the right and left, respectively.
The pupil size in bright surroundings was 5 mm in the right eye and 7 mm in the left eye, while 6 mm and 7 mm in the dark in the right and left eyes, respectively.
Despite treatment, her corectopia persisted, more pronounced in the right eye than the left.
The report demonstrates and corroborates previous cases in that corectopia is associated with midbrain pathology. The basal vein of Rosenthal typically runs laterally along with the tectal plate of the midbrain.
The patient had a prominent left basal vein of Rosenthal that would most likely result in a midbrain injury and posterior corectopia.
Furthermore, this patient had large pupils and sensitivity to light in both eyes with decreased deep tendon reflexes, consistent with the idiopathic Adie pupil, although pilocarpine supersensitivity suggested otherwise.
If your corectopia was not recognized, the diagnosis of AVM might not have been made.
A negative cholinergic supersensitivity test (as seen in this patient) does not exclude Adie’s pupil because this test is demonstrated in only 80% of people with this condition.
The sensitivity of this test can be increased to more than 90% by the second round of 0.1% pilocarpine application.
Several factors can influence this test, including intersubjective variability, differential corneal penetration, baseline pupil size (iris stroma), and reinnervation status.
Another explanation for the negative cholinergic supersensitivity test is an inverse relationship between the innervation of the iris sphincter segments and the response to dilute pilocarpine.
The possibility exists that the iris sphincter segments are less sensitive to dilute pilocarpine due to the reinnervation of these segments.
Midbrain corectopia has previously been described in patients with clinically significant intracranial hypertension and decreased consciousness with a poor prognosis, especially in acute cerebrovascular disorders.
Initially described by Wilson, Selhorst et al. subsequently confirmed the observation of corectopia and its importance as a sign of rostral midbrain dysfunction.
Midbrain core copy has also been seen in cases with transient midbrain dysfunction and is not considered a final sign.
The patient with posterior fossa intracranial pathology was alert, oriented, and without apparent cognitive impairment.
The case showed a minor involvement of the midbrain. Interestingly, the corectopia in our patient persisted despite treatment.
Different mechanisms of core copy have been suggested; however, the general principle relates to the balance between the sympathetic and parasympathetic pupillary pathways.
Lesions in the midbrain (oculomotor nerve or nucleus) will non-uniformly paralyze the pupillary sphincter, and corectopia occurs with dilation of the pupils through the sympathetic pathway.
Lesions in the pupillary fibers of the midbrain, as seen in partially innervated Edinger-Westphal nuclei, produce uneven upward and inward movement of the pupil.
In patients with paralyzed dilator muscles, corectopia occurs from partial central inhibition of sphincter tone.
Also, various sections of the pupillary sphincter have different levels of parasympathetic tone.