CASE REPORT of Plateau Iris
A 69-year-old woman first presented with left eye acute angle-closure with bilateral laser PI done in 1990. She subsequently developed another episode of bilateral acute angle-closure following pupil dilatation despite patent PI in January 2012 and was diagnosed as having Plateau Iris.
Gonioscopy revealed bilateral appositional angle closure with no peripheral anterior synechiae, but no double hump sign was seen. Bilateral ALPI was performed and the attack was subsequently aborted. Since the angles were still narrow, bilateral cataract extraction was performed, right eye in February and left eye in April 2012.
The intraocular pressure (IOP) remained in the range of teens in both eyes with no signs of glaucoma in subsequent follow-up.
In November 2013,
she presented with right eye AAC (IOP 48 mmHg). The cornea was edematous, the anterior chamber was quiet and the central anterior chamber was deep. The PI was patent and the ALPI marks were mostly at peripheral 2/3 of the iris.
The cup-disc ratio was normal. Gonioscopy was suboptimal due to poor corneal clarity but appeared to show grossly narrow angles with patchy closure. The attack was aborted medically. Anterior segment optical coherence tomography confirmed bilateral plateau iris configuration.
DISEASE Plateau Iris
PIS is a type of narrow-angle more commonly seen in younger adults that can lead to chronic angle-closure glaucoma.
Plateau iris refers to the anatomical configuration of the iris. Plateau iris is caused by a narrowing of the anterior chamber angle due to insertion of the iris anteriorly on the ciliary body or displacement of the ciliary body anteriorly, which in turn alters the position of the peripheral iris in relation to the trabecular meshwork (i.e. placing them in apposition).
Plateau iris syndrome is defined as a persistently narrow-angle capable of closure in spite of a patent iridotomy. It is an ocular condition that requires appropriate diagnosis and treatment in order to prevent vision loss.
Early recognition and intervention are key components to a good overall prognosis in this patient population.
All-fit Slit-Lamp Adapter
Record and share exactly what you see at the slit lamp. One adapter fits any slit lamp or surgical microscope — and any smartphone.
From Choroida — the team behind this siteMANAGEMENT
The primary treatment modality for patients with plateau iris configuration is surgical. Many clinicians, however, will first treat with miotic agents such as pilocarpine to prevent pupillary dilation leading up to surgery.
Low dose or dilute pilocarpine can produce thinning of the iris and facilitate the opening of the angle by pulling the iris away from the trabecular meshwork.
Document what you see
Two smartphone imaging tools built for everyday clinic use — one for the slit lamp, one for the fundus.
From Choroida — the team behind this siteREFERENCES
- Diniz Filho A, Cronemberger S, Merula RV, Calixto N. Plateau Iris. Arq Bras Oftalmol 2008;71(5):752-8.
- Wand M, Grant WM, Simmons RJ, Hutchinson BT. Plateau Iris Syndrome. Trans Sect Ophthalmol Am Acad Ophthalmol Otolaryngol. 1977;83(1):122-30.
- Ritch R, Chang B, Liebmann J. Angle Closure in Younger Patients. Ophthalmology. 2003; 110(10):1880-9. Review.
- Ultrasound Biomicroscopy (UBM) Clinical Database. Retrieved February 19, 2012.
- Kumar RS, Baskaran M, Chew PT, Friedman DS, Handa S, Lavanya R, et al. Prevalence of plateau iris in primary angle-closure suspects an ultrasound biomicroscopy study. Ophthalmology. Mar 2008;115(3):430-4
Read more about: Tadpole Pupil,Slit lamp Exam, Retinal imaging, Slit lamp exam
Test yourself
A few questions straight from this article.
-
How is plateau iris syndrome defined?
Plateau iris syndrome is defined as a persistently narrow angle still capable of closure in spite of a patent iridotomy, which is why an open iridotomy does not exclude the diagnosis. -
What anatomical abnormality underlies plateau iris?
The angle narrows because the iris inserts anteriorly on the ciliary body, or the ciliary body itself sits forward, pushing the peripheral iris into apposition with the trabecular meshwork. -
Plateau iris syndrome is a narrow-angle condition most commonly seen in which group?
Plateau iris syndrome is described as a form of narrow angle more commonly seen in younger adults, and it can progress to chronic angle-closure glaucoma. -
In the reported plateau iris case, what precipitated the bilateral acute angle-closure attack of 2012?
The patient closed bilaterally after her pupils were dilated, despite iridotomies that were still patent — the event that led to the plateau iris diagnosis. -
What did gonioscopy show when this patient with plateau iris was diagnosed?
Gonioscopy revealed bilateral appositional angle closure with no peripheral anterior synechiae, and no double hump sign was seen in this patient. -
Which imaging test confirmed bilateral plateau iris configuration in this patient?
With the cornea too hazy for good gonioscopy during the attack, anterior segment optical coherence tomography confirmed the bilateral plateau iris configuration. -
What intraocular pressure was recorded during this patient's acute angle-closure attack in the right eye?
The right eye presented in acute angle closure with an intraocular pressure of 48 mmHg and an oedematous cornea; the attack was aborted medically. -
During the acute attack in this plateau iris case, what was the state of the central anterior chamber?
Despite the acute attack, the anterior chamber was quiet and remained deep centrally, while the cornea was oedematous and the iridotomy stayed patent. -
Which miotic is used in plateau iris to prevent pupillary dilation before surgery?
Many clinicians bridge to surgery with a miotic such as pilocarpine; low-dose or dilute pilocarpine thins the iris and pulls it away from the trabecular meshwork. -
What is the primary treatment modality for patients with plateau iris configuration?
Surgery is the primary treatment modality for plateau iris configuration, with miotic agents used mainly as a holding measure in the run-up to it.
