Cysts of the Iris Pigment Epithelium. What Is New and Interesting? The 2016 Jose Rizal International Medal Lecture

Multimodal optical imaging of iris flocculi in three consecutive generations: a case report

Background

Multiple pigmented epithelial cysts at the edge of pupils, that is, iris flocculi, in both eyes, are rare ocular diseases. It has been demonstrated that this disease can be attributed to mutations in the smooth muscle α-actin 2 (ACTA2) gene, which mainly affects the function of smooth muscle cells (SMCs). SMCs are components of the iris, aorta, and several other systemic organs. In addition, iris flocculi are strongly correlated with familial thoracic aortic aneurysm and dissection (TAAD), which is caused by the mutation of amino acid 149 in the ACTA2 gene.

Case description

A 6-month-old Chinese boy was found to have iris flocculi during ocular fundus screening for premature infants. His mother, a 30-year-old Chinese woman with a history of aortic dissection, underwent an ophthalmic examination and was found to have iris flocculi. Whole exome sequencing revealed a heterozygous c.445C > T (p. Arg149Cys) mutation in ACTA2 in both the boy and his mother. After his family history was traced, the boy's grandfather was diagnosed with similar iris flocculi. Due to the absence of any ocular complications caused by iris flocculi in the cases, no special treatment was given, and regular follow-up was recommended.

Conclusion

We reported one case of familial iris flocculi caused by a heterozygous missense mutation in ACTA2 (p. Arg149Cys) and presented multimodal optical images of both the iris and fundus in three consecutive generations. This case report enriched the clinical features of retinal vasculature and macula associated with the mutation in the amino acid 149 of the ACTA2 gene.

Anterior segment swept-source optical coherence tomography and ultrasound biomicroscopy in iris and ciliary body lesions

OBJECTIVES

Differentiation of iris and ciliary body lesions as benign or malignant and cystic or solid is important. The aim of this study was to compare anterior segment swept-source optical coherence tomography (AS SS-OCT) and ultrasound biomicroscopy (UBM) findings in iris and ciliary body tumors.

RESEARCH DESIGN AND METHODS

Forty-two eyes of 38 cases with iris and ciliary body tumors imaged with UBM and AS SS-OCT between September 2018 and September 2023 were evaluated retrospectively.

RESULTS

Of 42 eyes, 14 had melanoma, 14 iris pigment epithelial (IPE) cysts, 7 nevi, 3 Lisch nodules, 2 iris stromal cysts, 1 pars plana cysts, and 1 iris mammillations. An equivalent (100%) visualization of the anterior tumor margin was obtained with both techniques. Compared to AS SS-OCT, UBM was superior for posterior margin visualization in melanocytic tumors and IPE cysts. Bland-Altman plots demonstrated good agreement between UBM and AS SS-OCT for melanocytic tumors < 2.5 mm in base diameter and < 2 mm in thickness.

CONCLUSIONS

Although, UBM is the gold standard for ciliary body and iridociliary tumors. AS SS-OCT should be considered as an excellent alternative to UBM, especially in minimally elevated iris lesions.

Imaging of Anterior Segment Tumours: A Comparison of Ultrasound Biomicroscopy Versus Anterior Segment Optical Coherence Tomography

Anterior segment tumours of the eye are relatively rare but can pose significant morbidity and mortality. We conducted a literature review to compare the performance of ultrasound biomicroscopy to anterior segment optical coherence tomography in the imaging of these tumours. A total of seven studies were included accounting for a cumulative 1,114 eyes. Ultrasound biomicroscopy has traditionally formed, and remains, the mainstay of tumour imaging due to its ability to penetrate pigmented lesions and delineate the posterior border of tumours, and the current evidence supports this.

A transcriptome atlas of the mouse iris at single-cell resolution defines cell types and the genomic response to pupil dilation

The iris controls the level of retinal illumination by controlling pupil diameter. It is a site of diverse ophthalmologic diseases and it is a potential source of cells for ocular auto-transplantation. The present study provides foundational data on the mouse iris based on single nucleus RNA sequencing. More specifically, this work has (1) defined all of the major cell types in the mouse iris and ciliary body, (2) led to the discovery of two types of iris stromal cells and two types of iris sphincter cells, (3) revealed the differences in cell type-specific transcriptomes in the resting vs. dilated states, and (4) identified and validated antibody and in situ hybridization probes that can be used to visualize the major iris cell types. By immunostaining for specific iris cell types, we have observed and quantified distortions in nuclear morphology associated with iris dilation and clarified the neural crest contribution to the iris by showing that Wnt1-Cre-expressing progenitors contribute to nearly all iris cell types, whereas Sox10-Cre-expressing progenitors contribute only to stromal cells. This work should be useful as a point of reference for investigations of iris development, disease, and pharmacology, for the isolation and propagation of defined iris cell types, and for iris cell engineering and transplantation.

Iris Cysts: Clinical Features, Imaging Findings, and Treatment Results

Objectives:

To report the clinical and demographic characteristics, imaging findings, treatment results, and follow-up data of patients with iris cysts.

Materials and Methods:

The medical records of 37 patients with iris cysts were retrospectively analyzed. Ultrasound biomicroscopy (UBM), swept-source optical coherence tomography (SS-OCT), and SS-OCT angiography (SS-OCTA) were performed to examine the iris cysts.

Results:

The mean age of the patients was 34.4 years, ranging from 5 to 85 years. Twenty-four patients (65%) were female and 13 (35%) were male. Mean follow-up period was 21.3 months, ranging from 4 months to 8 years. Thirty-five (94.5%) of the cysts were classified as primary and 2 (4.5%) were classified as secondary. Thirty-one (83.7%) of the primary cysts were pigment epithelial and 4 were stromal. Primary iris pigment epithelial cysts were classified as peripheral in 26 patients (72.2%), midzonal in 4 (11.1%), and dislodged in 1 (2.7%). Stromal cysts were classified as acquired in 3 patients (8.1%) and congenital in 1 patient (2.7%). Secondary iris cysts were caused by perforating eye injury. UBM could visualize both the anterior and posterior surfaces of the cysts (26 patients). Anterior segment SSOCT could visualize the anterior but not the posterior surface of the cysts (4 patients). Iris cysts did not display intrinsic vascularity on SS-OCTA (4 patients). All pigment epithelial cysts were managed by observation. Of the 4 primary stromal cysts, 3 were managed by surgical excision and 1 by observation. Two secondary cysts required surgical removal.

Conclusion:

Pigment epithelial cysts generally remain stable without need for treatment. However, iris stromal cysts frequently require surgical intervention. UBM and SS-OCT were valuable in the diagnosis of iris cysts. On UBM, iris cysts appear with a thin, hyperechoic wall with hypoechoic internal content. Iris cysts did not have intrinsic vascularity on anterior segment SS-OCTA.

Clinical Features of Iris Cysts in Long-Term Follow-Up

This study evaluated the characteristics and clinical course of patients with iris cysts in the long-term follow-up (24–48 months). We retrospectively analyzed the medical records of 39 patients with iris cysts (27 women and 12 men). Age, visual acuity, intraocular pressure (IOP), slit-lamp evaluation, and ultrasound biomicroscopy images were assessed. The mean age at diagnosis was 40.6 ± 17.48 years. Thirty (76.9%) cysts were peripheral, five (12.8%) were located at the pupillary margin, two (5.1%) were midzonal, and two (5.1%) were multichamber cysts extending from the periphery to the pupillary margin. A total of 23 (59%) cysts were in the lower temporal quadrant, 11 (28.2%) were in the lower nasal quadrant, and 5 (12.8%) were in the upper nasal quadrant. Cyst size was positively correlated with patient age (rs = 0.38, p = 0.003) and negatively correlated with visual acuity (rs = −0.42, p = 0.014). Cyst growth was not observed. The only complication was an increase in IOP in three (7.7%) patients with multiple cysts. The anatomical location of the cysts cannot differentiate them from solid tumors. The vast majority of cysts are asymptomatic, do not increase in size, and do not require treatment during long-term follow-up.

Clinical observations of iridociliary cysts and their changes after implantable collamer lens implantation in myopic patients

AIM

To observe the characteristics of iridociliary cysts in myopic patients and evaluate the influences on the position and safety of implantable collamer lens (ICL) after surgery.

METHODS

Totally 270 eyes of 135 patients who underwent ICL surgery for the corrections of myopia were included in this study. Preoperative and postoperative morphology of iridociliary cysts were observed in ultrasonic biomicroscopy (UBM) image.

RESULTS

A total of 138 iridociliary cysts were found in 88 eyes of 50 patients among 270 eyes of 135 patients before surgery (37%). Twenty-five patients had cysts in one eye (50%) and 25 had cysts in both eyes (50%). The prevalence of iridociliary cysts was negatively correlated with age, but no gender difference (P>0.05). The incidence of iridociliary cysts was much less in eyes with myopia greater than -9.00 D (P<0.05). The diameter of the largest cyst was 1.96 mm and the smallest cyst was 0.24 mm, with a majority within the range of 0.5 to 1.0 mm. Most of the cysts were located in the inferior temporal quadrant. One year after ICL implantation, 51 iridociliary cysts (37%) remained unchanged, 47 cysts (34%) decreased in size, and 40 cysts (29%) disappeared. Most of cysts that changed after surgery were smaller than 1.0 mm (P<0.05) and located in the nasal and temporal sides around the haptics of implantable lens. All the ICL were in their original position.

CONCLUSION

Iridociliary cysts are commonly seen in myopic eyes. The cysts have no impact on the safety of ICL surgery. Some cysts may decrease in size or disappear after ICL implantation.

Implantable collamer lens surgery in patients with primary iris and/or ciliary body cysts

BACKGROUND

The prevalence of primary iris and/or ciliary body cysts is common in myopia, though asymptomatic in nearly all cases. It's a very valuable thing to study the clinical safety and reliability of implantable collamer lens (ICL) surgery in patients with primary iris and/or ciliary body cysts.

METHODS

A total of 108 patients (201 eyes) were included in this retrospective study. All eyes had been implanted with V4c implantable collamer lens (ICLV4c). According to the eyes with or without primary iris and/or ciliary body cysts, all eyes were divided into two groups. We observed preoperative and postoperative uncorrected distance visual acuity (UDVA), corrected distance visual acuity)(CDVA), intra-ocular pressure(IOP), anterior chamber volume(ACV), anterior chamber depth(ACD), trabecular-iris angle (TIA), angle opening distance at 500 μm (AOD500),vertical central distance between the corneal endothelium and the front surface of ICL(CE-ICL), and the central vault. The follow-up periods covered 12 months.

RESULTS

Among all the 201 eyes, primary iris and/or ciliary body cysts were detected in 54 eyes (26.87%),but the prevalence was account to 36.11%(18males,21females).There were 30 eyes (55.56%) with unilateral single cyst, 12 eyes (22.22%) with unilateral double cysts, 12 eyes (22.22%) eyes with unilateral multiple and/or multi-quadrants cysts, the mean size of cysts was (0.714 ± 0.149)mm(range from 0.510 to 1.075 mm).30.4% of the cysts were located at iridociliary sulcus, 65.5% in pars plicata, and 4.1% in midzonal iris, which showed a characteristic distribution pattern, with cysts found predominantly in the inferior and temporal quadrants.The postoperative size and the number of cysts showed nearly no changes. The postoperative ACV, AOD500 and TIA showed a statistical reduction in both two groups (P < 0.05), but with no statistical significant between the two groups (P > 0.05), the parameters of postoperative IOP,CE-ICL and central vault also showed the same results as which. We did not observe serious complication and IOP elevating in the whole follow-up periods.

CONCLUSION

Primary iris and/or ciliary body cysts are not absolutely contraindication for ICL surgery. For some single cyst smaller than 1.075 mm or single quadrant cysts located at ciliary body are rare to lead some serious complications. But, for some multiple cysts, especially multi-quadrants cysts located at iridociliary sulcus, we still should remain cautions.

Advanced Midzonal Iris Pigment Epithelial Cyst Managed by Aspiration Deflation

BACKGROUND

There are several cysts that can occur in the iris. The midzonal (retroiridic) iris pigment epithelial (IPE) cyst is important because it can simulate melanoma of the ciliary body. However, it is frequently asymptomatic and requires no treatment.

METHODS

A 37-year-old asymptomatic woman with visual acuity of 20/20 in each eye was found to have an elevated mass behind the left iris, presumed to be melanoma, and was referred for management. On our examination, there was a typical midzonal IPE cyst in the left eye (OS), requiring observation without intervention. After 4 years, she developed progressive visual loss to 20/40 OS and cyst enlargement was noted, obstructing most of the visual axis and causing partial lens subluxation. Translimbal fine needle aspiration deflation with a 30-G needle was performed.

RESULTS

Immediately at aspiration, the cyst demonstrated collapse, disappearing behind the iris stroma, and the lens subluxation resolved. Visual acuity returned to 20/20 OS and has remained stable without recurrence for 3 years.

CONCLUSION

Although most midzonal IPE cysts are asymptomatic, this case showed progressive enlargement with visual loss and was managed with translimbal aspiration. Symptomatic midzonal IPE cysts can be deflated with translimbal aspiration rather than more aggressive surgical excision.

Iris cysts: A comprehensive review on diagnosis and treatment

Iris cysts, both primary and secondary, are a diagnostic and treatment challenge. Primary cysts arise either from the iris pigment epithelium or the iris stroma. Posterior pigment epithelial cysts are subdivided according to their location as central, midzonal, and peripheral. Iris stromal cysts are classified either as congenital or acquired. Free-floating cysts are usually dislodged pigment epithelial cysts. Secondary cysts are classified according to the underlying cause as implantation cysts, drug-induced, uveitic, tumor-induced, parasitic, or as cysts associated with systemic disorders. Differential diagnosis is based on the clinical presentation and imaging. Ultrasound biomicroscopy is the gold standard for the imaging of iris cysts, combining excellent resolution with sufficient tissue penetration. Treatment of iris cysts depends largely on whether they become symptomatic or not. Symptoms include obstruction of the visual axis, corneal decompensation, secondary uveitis, and secondary glaucoma. Treatment options cover a range from simple observation to fine-needle aspiration (with or without intracystic injection of absolute alcohol or antimitotic agents), laser (argon, Nd:YAG), or surgical excision. In the past, the prevailing notion was that of a radical surgical intervention in the form of iridectomy or iridocyclectomy. Given the high rate of recurrence, a stepwise conservative approach is currently favored by most clinicians.