Page 171 - July-August 2020

FIGURE 3. UBM OF PERIPHERAL CYST. YELLOW LINE IS FIGURE 4. UBM OF MIDZONAL CYST. YELLOW LINE IS TRACING
TRACING THE HEIGHT OF THE CYSTIC CAVITY THE LENGTH OF THE CYSTIC CAVITY

Midzonal or retroiridic IPE cysts and the surrounding tissues can be alcohol or antimitotic agents such
are best seen after pupil dilation. seen when using this technology as mitomycin-C or -fluorouracil
5
They are dark brown, round or (Figures 3 and 4). In addition, UBM to achieve a more permanent cyst
fusiform and just like central cysts can help differentiate a cyst from regression. Laser treatment using
4
are lined by pigment epithelium a solid tumor. Solid tumors that either thermal (argon or diode) or
5
making them impenetrable to light can mimic these cysts include iris Nd:YAG laser to perforate the cyst
by transillumination (Figure 1). melanoma, ciliary body melanoma wall can drain the cyst. Surgical
4
2,4
Midzonal cysts occur most frequently and IPE adenoma. Although excision, if necessary, would be
in patients over 60 years of age. 1 anterior segment optical coherence based on the extent of involvement
tomography can display the anterior of the cyst.
Peripheral IPE cysts are located at border of an iris lesion in good detail,
the iridociliary sulcus. These are the the imaging of structures located REFERENCES
most common of all the IPE cysts. behind the iris pigment epithelium 1. Shields CL, Kancherla S, Patel J, et
They usually cannot be visualised and the internal structure of the al. Clinical survey of 3680 iris tumors
even with maximal pupil dilation. lesion is usually insufficient. based on patients age at presentation.
6
Clinically they will present as an Ophthalmology 2012; 119: 407-14.
anterior bulge of the iris stroma TREATMENT 2. Shields JA, Shields CL. Cysts of the iris
(Figure 2). They are round in shape pigment epithelium. What is new and
and clear, transmitting light because Since IPE cysts are benign interesting? Asia-Pac J Ophthalmol 2017;
of being covered by nonpigmented and usually asymptomatic, no 1: 64-9.
ciliary epithelium. 2,4 treatment is necessary and they 3. Chamney S, McGimpsey S, McConnell V,
can just be monitored annually. et al. Iris flocculi as an ocular marker of
Some IPE cysts can become If a cyst occludes the visual axis ACTA2 mutation in familial thoracic aortic
spontaneously dislodged and float or compresses and occludes the aneurysms and dissections. Ophthalmic
freely in the aqueous or vitreous anterior chamber angle, then Genet 2015; 36: 86-8.
humor. They can be visualised treatment is indicated. Fine-needle 4. Georgalas I, Petrou P, Papaconstantinou
2
by gonioscopy if they lodge in the aspiration is a controlled, method to D, et al. Iris cysts: A comprehensive
review on diagnosis and treatment. Surv
anterior chamber angle. deflate a cyst. This can be combined Ophthalmol 2018; 63: 347-64.
with intracystic injection of absolute
IMAGING 5. Bianciotto C, Shields CL, Guzman JM,
et al. Assessment of anterior segment
Central IPE cysts can be visualised MIDZONAL OR tumors with ultrasound biomicroscopy
directly with slit-lamp examination. RETROIRIDIC IPE versus anterior segment optical
Most dislodged and free-floating CYSTS ARE BEST coherence tomography in 200 cases.
cysts can also be visualised SEEN AFTER PUPIL Ophthalmology 2011; 118: 1297-1302.
directly. Midzone and peripheral DILATION. THEY OCCUR 6. Pong JCF, Lai JSM. Imaging of primary
cyst of the iris pigment epithelium using
IPE cysts are best evaluated using MOST FREQUENTLY anterior segment OCT and ultrasonic
ultrasound biomicroscopy (UBM). IN PATIENTS OVER 60 biomicroscopy. Clin Exp Optom 2009;
The entire structure of the cyst YEARS OF AGE 92: 139-41.

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