- Email: [email protected]
Multiple bilateral iridociliary cysts: ultrasound biomicroscopy and clinical characteristics
Multiple bilateral iridociliary cysts: ultrasound biomicroscopy and clinical characteristics John A. McWhae,*† MD, FRCSC; Monique Rinke,† COMT; Andrew C.S. Crichton,*† MD, FRCSC; Case Van Wyngaarden,* MD ABSTRACT • RÉSUMÉ
Background: To describe the utility of ultrasound biomicroscopy in diagnosing multiple bilateral iridociliary cysts and to determine the clinical significance of this condition. Methods: A retrospective review of 73 patients referred for ultrasound biomicroscopy who were found to have bilateral iridociliary cysts. Results: Seventy-three patients were identified who demonstrated 2 or more cysts in 1 eye and at least 1 in the other with ultrasound biomicroscopy. A solitary iris elevation was the most common reason for referral (84.9%). There were 44 patients for whom sufficient follow-up data were available, with a mean follow-up of 40.4 months. Clinical sequelae included 1 case of sectoral cataract (2.3%) and 4 cases of cyst-related glaucoma (9.1%). Interpretation: Multiple bilateral iridociliary cysts is a common condition with occasional clinical significance. Ultrasound biomicroscopy is a valuable technique in diagnosing this condition. Patients who have significant angle compromise should be followed and treated as required for glaucoma. Contexte : Décrire l’utilité de la biomicroscopie à l’ultrason pour diagnostiquer les kystes irido-ciliaires bilatéraux multiples et déterminer l’importance clinique de ces derniers. Méthodes : On a fait une étude rétrospective de 73 patients qui avaient été soumis à une biomicroscopie à l’ultrason, laquelle avait révélé des kystes irido-cyliaires bilatéraux. Résultats : L’on a retenu les 73 patients dont on avait établi par la biomicroscopie à l’ultrason qu’ils avaient 2 kystes et plus dans 1 œil et au moins 1 dans l’autre. Une élévation solitaire de l’iris a été la raison la plus fréquente de l’adresse des patients au spécialiste (84,9 %). En tout, 44 patients ont eu un suivi de 40,4 mois. Les séquelles cliniques comprirent la cataracte sectorielle (2,3 %) et le glaucome associé à un kyste (9,1 %). Interprétation : Les kystes irido-ciliaires bilatéraux multiples sont des pathologies fréquentes qui revêtent occasionnellement une importance clinique. La biomicroscopie à l’ultrason est, pour ces cas, une technique de diagnostic précieuse. Les patients qui ont un important compromis angulaire devraient être suivis et soignés comme le demande le glaucome.
ridociliary cysts have been a source of diagnostic confusion in ophthalmology for many years.1 The recent development of ultrasound biomicroscopy (UBM)2 has been a substantial step forward and has allowed precise diagnosis of these lesions.3 In the past, multiple bilateral iridociliary cysts have been described as a relatively rare cause of angle-closure glaucoma.4 Vella et al described a familial pattern to this condition. Recent papers,5,6 looking at groups of both isolated and multiple bilateral
I
cysts, suggest a generally benign course. The purpose of our study was to try to determine the clinical significance of multiple bilateral iridociliary cysts and the natural history of the condition, and to make follow-up recommendations regarding these patients. In a 1996 article, Augsberger et al7 pointed out that patients with multiple cysts in one eye frequently had cysts identified in the fellow eye when examined with UBM. Pavlin6 suggested that iridociliary cysts are
From *the University of Calgary, Calgary, Alta., and †the Rockyview General Hospital, Calgary, Alta.
Correspondence to: John A. McWhae, MD, Suite 201, 506 71st Ave. SW, Calgary AB T2V 4V4; [email protected]
Presented at SIDUO XX, Congress of the International Society for Ophthalmic Ultrasound in Budapest, September 2004, and in part at the Ocular Oncology Congress in Philadelphia, 1999
This article has been peer-reviewed. Cet article a été évalué par les pairs.
Originally received Jan. 26, 2006. Revised July 6, 2006 Accepted for publication Oct. 31, 2006
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Can J Ophthalmol 2007;42:268–71 doi: 10.3129/can.j.ophthalmol.i07-017
Cysts and ultrasound biomicroscopy—McWhae et al
common but rarely had significant clinical complications. Kunimatsu8 performed a prospective study on both eyes of 116 normal subjects and detected a surprisingly high incidence of cysts at 54.3%. Incidences of cysts tended to be high at younger ages and bilaterality was common. It has become apparent that iridociliary cysts are extremely common, usually asymptomatic, and usually clinically undetectable during slit-lamp examination. It therefore becomes important to identify which of this very large group of patients require ongoing follow-up. Reports of cystic angle-closure glaucoma9–11 are all related to multiple rather than isolated iridociliary cysts. This group of patients, therefore, became the focus of our interest in this study. We defined multiple bilateral iridociliary cysts as patients having 2 or more iridociliary cysts in 1 eye and at least 1 in the other as seen with UBM. METHODS
A retrospective study of patients having UBM between February 1995 and February 2004 identified 73 patients who had multiple bilateral iridociliary cysts. Follow-up information was collected from clinic charts as well as by contacting referring ophthalmologists. Ethics approval for the study was obtained from the conjoint health research ethics board at the University of Calgary. A Zeiss-Humphrey instrument (model 840) ultrasound biomicroscope (no longer available) and later a Paradigm UBM Plus (model P45, Salt Lake City, Utah) were used. Both machines used 50 MHz transducers. Examinations were performed using an eyecup filled with methylcellulose solution after topical anesthetic drops were applied. Radial scanning was performed over the area in question and then continued around the remainder of the angle for 360°. As we have previously described12 the probe marker was oriented away from the limbus for the clock hours between 12 o’clock to 5:30, and then towards the limbus from 6:00 o’clock back to 11:30. When looking at the printed scans, this provides an orientation similar to the surgeon’s view of the anterior segment. When looking at an individual scan labelled for the right or left eye, this allows one to identify whether it is a temporal or nasal scan. Beginning in 1998 we routinely recommended scanning of the second eye if more than one cyst was identified in the indicated eye. For each patient who was referred for UBM, we recorded age, sex, clinical presentation, intraocular pressure, and presence or absence of glaucoma. Location and
number of cysts were identified. Clinical follow-up parameters included the months of follow-up, intraocular pressure, presence or absence of glaucoma, and treatment details for glaucoma. For the purposes of the study we defined glaucoma as elevated intraocular pressure or angle compromise that required treatment. RESULTS
We identified 73 patients with multiple bilateral iridociliary cysts. The reasons for referral are summarized in Table 1. The most common reason for referral was a bulge in the peripheral iris with the differential diagnosis including a ciliary body tumour or iris cyst. Two patients had cyst-related glaucoma at presentation and one had cataract. A further separate analysis was done on this group of patients. This is summarized in Table 2. We were able to obtain follow-up data on 44 of the 73 patients (60.3%). The mean period of follow-up was 40.4 months. With additional clinical data more glaucoma suspects were identified. Five patients (11.4%) had glaucoma during the follow-up period. This includes all patients requiring treatment for elevated intraocular pressure or angle compromise. Of these, 4 had cyst-related angle closure. In these patients, the UBM demonstrated significant angle closure in areas with underlying cysts. In the other case, the glaucoma was probably not related to cysts. One Table 1—Reason for referral of 73 patients with multiple bilateral iridociliary cysts No. (%) Male Female Age, mean (range), years Reason for referral One or more iris bulges or elevations, or suspected cysts or mass Clinically visible cysts Narrow angles, increased IOP, or atypical glaucoma Focal cataract
25 (34.2) 48 (65.7) 37.1 (8–82) 62 (84.9) 3 (4.1) 7 (9.6) 1 (1.4)
Data are No. (%) unless otherwise specified.
Table 2—Clinical manifestations in 44 of 73 patients with clinical follow-up data No. (%) Focal cataract Cyst-related glaucoma requiring treatment Glaucoma suspects followed for cyst-related narrow angles Cases of clinical cyst enlargement Follow-up, mean, months
1 (2.3) 4 (9.1) 4 (9.1) 0 (0) 40.4
Data are No (%) unless otherwise specified.
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patient (2.3%) was identified who had focal cataract at presentation. Cyst-related glaucoma treatment was required in 4 patients. Four patients had laser iridotomies performed. These were done over cystic elevations where possible. Two of these were prophylactic due to a perceived risk of acute angle closure and 2 were performed in the setting of elevated pressure. Two patients also required topical timolol therapy. No patients required repeat laser treatment over the period of follow-up. We include 2 case presentations that demonstrate the utility of UBM in this condition. The first is a 67-yearold man who presented with elevated pressure and a suspected right iris tumour in 1996. Intraocular pressures measured 21 mm Hg in the right eye and higher in the left at 30 mm Hg. Slit-lamp examination revealed a marked right iris elevation inferiorly. Bullous pigmented lesions were seen at the inferior pupil margin (Fig. 1). Gonioscopy demonstrated complete closure of most of the inferior half of the angle. Gonioscopy was open on the left side. The glaucoma on the left eye was diagnosed as open-angle glaucoma. The patient had glaucomatous
cupping with a cup/disc ratio of 0.9 OD and 0.7 OS and moderate visual field damage in both eyes. Ultrasound biomicroscopy of the right eye revealed 3 very large iridociliary cysts extending from the anterior ciliary body to beyond the pupil margin inferiorly (Figs. 2 and 3). UBM of the left eye demonstrated multiple cysts without angle compromise. Urgent treatment of the right eye was undertaken. Three YAG laser iridotomies were performed over the inferior iris. These were placed so they would be overlying the cysts. It was possible to visualize the cysts collapsing immediately after treatment. Topical timolol 0.5% was begun in the left eye and 2 weeks later the intraocular pressure measured 16 mm Hg in both eyes. Given the amount of disc damage it was elected to add timolol to the right eye also. Most recent clinical follow-up in July 2005 revealed a stable visual field. Intraocular pressures were stable at 11 mm Hg on timolol drops in each eye. The second case is of a 53-year-old woman who was noted to have a presenile localized cataract temporally in the right eye. UBM was requested to assess this area further (Fig. 4). An iris root cyst was identified that appeared to be contacting the peripheral lens. A localized increased reflectivity in the lens was noted that corre-
Fig. 1—Slit-lamp photograph of bulges above the pupil margin.
Fig. 3—Ultrasound biomicroscopy of multiple cysts in inferior angle.
Fig. 2—Ultrasound biomicroscopy of inferior angle showing large cyst.
Fig. 4—Ultrasound biomicroscopy of cyst touching peripheral lens.
Cases
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sponded with the cataract seen. The patient underwent an uncomplicated cataract extraction with intraocular lens implantation and achieved 6/6 vision postoperatively. Over the study period we had no clinical incidence of progressive cyst enlargement. Repeat UBMs were performed in 3 patients who were referred for a repeat study. One patient had a repeat UBM 4 times. In none of these cases was there evidence of cyst enlargement. There was only 1 familial case within the series. There was 1 mother and 1 adult daughter who both had multiple bilateral iridociliary cysts. Both were asymptomatic and had normal intraocular pressure. At our recommendation the other daughter had bilateral UBM performed and no cysts were identified. INTERPRETATION
Our understanding of iridociliary cysts has come a long way since the advent of UBM in the early 1990s. It appears that these are far more common than originally thought. Given the relatively young mean age of patients in our study and also in that of Kunimatsu,8 we suspect either these are congenital lesions or they developed early in life. They generally appeared to be nonprogressive. Cyst-related glaucoma occurred in patients that had multiple areas of angle compromise due to large cysts. Despite an interesting case report,4 familial occurrence of cystic angle-closure glaucoma appears to be rare. It should be noted that glaucoma is probably over-represented in our study because we receive many referrals from a high volume glaucoma clinic located on site. In terms of glaucoma treatment, there appears to be a role for laser iridotomy in patients whose cysts contribute to angle compromise. We had no incidence of diplopia when iridotomy was performed overlying iris cysts. This theoretically should not be possible, as the pigmented posterior wall of the cyst remains intact. Lasering of the cyst wall directly through the pupil orifice is technically more difficult and may result in lens complications. It is our impression that iridociliary cysts generally do not enlarge. Cyst-related angle-closure glaucoma probably occurs when age-related chamber shallowing further compromises an angle already narrowed by cysts. Additional studies would be needed to confirm this. We make the following recommendations for patient follow-up on the basis of our study results and a review of recent papers on the subject. Patients referred for UBM who are found to have an iridociliary cyst should
have 360° scanning in the indicated eye. Consideration should be given to scanning both eyes. This helps identify any potential angle compromise in either eye. Patients with multiple bilateral cysts that compromise the angle should be followed as glaucoma suspects and treated as required. Patients with no or less than 1 clock hour of angle narrowing should not require follow-up. Ultrasound biomicroscopy should be considered in atypical cases of narrow-angle glaucoma. This will help differentiate cases of cystic angle closure. Laser iridotomy overlying the cysts and (or) peripheral iridotomy are effective treatments. REFERENCES 1. Rosen E, Rosen R. Ciliary body cysts. Eye Ear Nose Throat Mon 1971;50:288–93. 2. Pavlin CJ, Foster FS. Ultrasound Biomicroscopy of the Eye. New York, NY: Springer-Verlag; 1995. 3. Marigo FA, Esaki K, Finger PT, et al. Differential diagnosis of anterior segment cysts by ultrasound biomicroscopy. Ophthalmology 1999;106:2131–5. 4. Vela A, Rieser JC, Campbell DG. The heredity and treatment of angle-closure glaucoma secondary to iris and ciliary body cysts. Ophthalmology 1984;91:332–7. 5. Lois N, Shields CL, Shields JA, Mercado G. Primary cysts of the iris pigment epithelium. Clinical features and natural course in 234 patients. Ophthalmology 1998;105:1879–85. 6. Fine N, Pavlin CJ. Primary cysts in the iridociliary sulcus: Ultrasound biomicroscopic features of 210 cases. Can J Ophthalmol 1999;34:325–9. 7. Augsburger JJ, Affel LL, Benarosh DA. Ultrasound biomicroscopy of cystic lesions of the iris and ciliary body. Trans Am Ophthalmol Soc 1996;94:259–71. 8. Kunimatsu S, Araie M, Ohara K, Hamada C. Ultrasound biomicroscopy of ciliary body cysts. Am J Ophthalmol 1999;127: 48–55. 9. Azura-Blanco A, Spaeth GL, Araujo SV, Augsburger JJ, Terebuh AK. Plateau iris syndrome associated with multiple ciliary body cysts. Report of three cases. Arch Ophthalmol 1996;114:666–8. 10. Tanihara H, Akita J, Honjo M, Honda Y. Angle closure caused by multiple, bilateral iridociliary cysts. Acta Ophthalmology Scand 1997;75:216–7. 11. Kuchenbecker J, Motschmann M, Schmitz K, BehrensBaumann W. Laser iridocystotomy for bilateral acute angleclosure glaucoma secondary to iris cysts. Am J Ophthalmol 2000;129:391–3. 12. McWhae JA, Crichton ACS, Rinke M. Ultrasound biomicroscopy for the assessment of zonules after ocular trauma. Ophthalmology 2003;110:1340–3. Key words: glaucoma, angle closure, cataract
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Background: To describe the utility of ultrasound biomicroscopy in diagnosing multiple bilateral iridociliary cysts and to determine the clinical significance of this condition. Methods: A retrospective review of 73 patients referred for ultrasound biomicroscopy who were found to have bilateral iridociliary cysts. Results: Seventy-three patients were identified who demonstrated 2 or more cysts in 1 eye and at least 1 in the other with ultrasound biomicroscopy. A solitary iris elevation was the most common reason for referral (84.9%). There were 44 patients for whom sufficient follow-up data were available, with a mean follow-up of 40.4 months. Clinical sequelae included 1 case of sectoral cataract (2.3%) and 4 cases of cyst-related glaucoma (9.1%). Interpretation: Multiple bilateral iridociliary cysts is a common condition with occasional clinical significance. Ultrasound biomicroscopy is a valuable technique in diagnosing this condition. Patients who have significant angle compromise should be followed and treated as required for glaucoma. Contexte : Décrire l’utilité de la biomicroscopie à l’ultrason pour diagnostiquer les kystes irido-ciliaires bilatéraux multiples et déterminer l’importance clinique de ces derniers. Méthodes : On a fait une étude rétrospective de 73 patients qui avaient été soumis à une biomicroscopie à l’ultrason, laquelle avait révélé des kystes irido-cyliaires bilatéraux. Résultats : L’on a retenu les 73 patients dont on avait établi par la biomicroscopie à l’ultrason qu’ils avaient 2 kystes et plus dans 1 œil et au moins 1 dans l’autre. Une élévation solitaire de l’iris a été la raison la plus fréquente de l’adresse des patients au spécialiste (84,9 %). En tout, 44 patients ont eu un suivi de 40,4 mois. Les séquelles cliniques comprirent la cataracte sectorielle (2,3 %) et le glaucome associé à un kyste (9,1 %). Interprétation : Les kystes irido-ciliaires bilatéraux multiples sont des pathologies fréquentes qui revêtent occasionnellement une importance clinique. La biomicroscopie à l’ultrason est, pour ces cas, une technique de diagnostic précieuse. Les patients qui ont un important compromis angulaire devraient être suivis et soignés comme le demande le glaucome.
ridociliary cysts have been a source of diagnostic confusion in ophthalmology for many years.1 The recent development of ultrasound biomicroscopy (UBM)2 has been a substantial step forward and has allowed precise diagnosis of these lesions.3 In the past, multiple bilateral iridociliary cysts have been described as a relatively rare cause of angle-closure glaucoma.4 Vella et al described a familial pattern to this condition. Recent papers,5,6 looking at groups of both isolated and multiple bilateral
I
cysts, suggest a generally benign course. The purpose of our study was to try to determine the clinical significance of multiple bilateral iridociliary cysts and the natural history of the condition, and to make follow-up recommendations regarding these patients. In a 1996 article, Augsberger et al7 pointed out that patients with multiple cysts in one eye frequently had cysts identified in the fellow eye when examined with UBM. Pavlin6 suggested that iridociliary cysts are
From *the University of Calgary, Calgary, Alta., and †the Rockyview General Hospital, Calgary, Alta.
Correspondence to: John A. McWhae, MD, Suite 201, 506 71st Ave. SW, Calgary AB T2V 4V4; [email protected]
Presented at SIDUO XX, Congress of the International Society for Ophthalmic Ultrasound in Budapest, September 2004, and in part at the Ocular Oncology Congress in Philadelphia, 1999
This article has been peer-reviewed. Cet article a été évalué par les pairs.
Originally received Jan. 26, 2006. Revised July 6, 2006 Accepted for publication Oct. 31, 2006
268
Cysts and ultrasound biomicroscopy—McWhae et al
Can J Ophthalmol 2007;42:268–71 doi: 10.3129/can.j.ophthalmol.i07-017
Cysts and ultrasound biomicroscopy—McWhae et al
common but rarely had significant clinical complications. Kunimatsu8 performed a prospective study on both eyes of 116 normal subjects and detected a surprisingly high incidence of cysts at 54.3%. Incidences of cysts tended to be high at younger ages and bilaterality was common. It has become apparent that iridociliary cysts are extremely common, usually asymptomatic, and usually clinically undetectable during slit-lamp examination. It therefore becomes important to identify which of this very large group of patients require ongoing follow-up. Reports of cystic angle-closure glaucoma9–11 are all related to multiple rather than isolated iridociliary cysts. This group of patients, therefore, became the focus of our interest in this study. We defined multiple bilateral iridociliary cysts as patients having 2 or more iridociliary cysts in 1 eye and at least 1 in the other as seen with UBM. METHODS
A retrospective study of patients having UBM between February 1995 and February 2004 identified 73 patients who had multiple bilateral iridociliary cysts. Follow-up information was collected from clinic charts as well as by contacting referring ophthalmologists. Ethics approval for the study was obtained from the conjoint health research ethics board at the University of Calgary. A Zeiss-Humphrey instrument (model 840) ultrasound biomicroscope (no longer available) and later a Paradigm UBM Plus (model P45, Salt Lake City, Utah) were used. Both machines used 50 MHz transducers. Examinations were performed using an eyecup filled with methylcellulose solution after topical anesthetic drops were applied. Radial scanning was performed over the area in question and then continued around the remainder of the angle for 360°. As we have previously described12 the probe marker was oriented away from the limbus for the clock hours between 12 o’clock to 5:30, and then towards the limbus from 6:00 o’clock back to 11:30. When looking at the printed scans, this provides an orientation similar to the surgeon’s view of the anterior segment. When looking at an individual scan labelled for the right or left eye, this allows one to identify whether it is a temporal or nasal scan. Beginning in 1998 we routinely recommended scanning of the second eye if more than one cyst was identified in the indicated eye. For each patient who was referred for UBM, we recorded age, sex, clinical presentation, intraocular pressure, and presence or absence of glaucoma. Location and
number of cysts were identified. Clinical follow-up parameters included the months of follow-up, intraocular pressure, presence or absence of glaucoma, and treatment details for glaucoma. For the purposes of the study we defined glaucoma as elevated intraocular pressure or angle compromise that required treatment. RESULTS
We identified 73 patients with multiple bilateral iridociliary cysts. The reasons for referral are summarized in Table 1. The most common reason for referral was a bulge in the peripheral iris with the differential diagnosis including a ciliary body tumour or iris cyst. Two patients had cyst-related glaucoma at presentation and one had cataract. A further separate analysis was done on this group of patients. This is summarized in Table 2. We were able to obtain follow-up data on 44 of the 73 patients (60.3%). The mean period of follow-up was 40.4 months. With additional clinical data more glaucoma suspects were identified. Five patients (11.4%) had glaucoma during the follow-up period. This includes all patients requiring treatment for elevated intraocular pressure or angle compromise. Of these, 4 had cyst-related angle closure. In these patients, the UBM demonstrated significant angle closure in areas with underlying cysts. In the other case, the glaucoma was probably not related to cysts. One Table 1—Reason for referral of 73 patients with multiple bilateral iridociliary cysts No. (%) Male Female Age, mean (range), years Reason for referral One or more iris bulges or elevations, or suspected cysts or mass Clinically visible cysts Narrow angles, increased IOP, or atypical glaucoma Focal cataract
25 (34.2) 48 (65.7) 37.1 (8–82) 62 (84.9) 3 (4.1) 7 (9.6) 1 (1.4)
Data are No. (%) unless otherwise specified.
Table 2—Clinical manifestations in 44 of 73 patients with clinical follow-up data No. (%) Focal cataract Cyst-related glaucoma requiring treatment Glaucoma suspects followed for cyst-related narrow angles Cases of clinical cyst enlargement Follow-up, mean, months
1 (2.3) 4 (9.1) 4 (9.1) 0 (0) 40.4
Data are No (%) unless otherwise specified.
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patient (2.3%) was identified who had focal cataract at presentation. Cyst-related glaucoma treatment was required in 4 patients. Four patients had laser iridotomies performed. These were done over cystic elevations where possible. Two of these were prophylactic due to a perceived risk of acute angle closure and 2 were performed in the setting of elevated pressure. Two patients also required topical timolol therapy. No patients required repeat laser treatment over the period of follow-up. We include 2 case presentations that demonstrate the utility of UBM in this condition. The first is a 67-yearold man who presented with elevated pressure and a suspected right iris tumour in 1996. Intraocular pressures measured 21 mm Hg in the right eye and higher in the left at 30 mm Hg. Slit-lamp examination revealed a marked right iris elevation inferiorly. Bullous pigmented lesions were seen at the inferior pupil margin (Fig. 1). Gonioscopy demonstrated complete closure of most of the inferior half of the angle. Gonioscopy was open on the left side. The glaucoma on the left eye was diagnosed as open-angle glaucoma. The patient had glaucomatous
cupping with a cup/disc ratio of 0.9 OD and 0.7 OS and moderate visual field damage in both eyes. Ultrasound biomicroscopy of the right eye revealed 3 very large iridociliary cysts extending from the anterior ciliary body to beyond the pupil margin inferiorly (Figs. 2 and 3). UBM of the left eye demonstrated multiple cysts without angle compromise. Urgent treatment of the right eye was undertaken. Three YAG laser iridotomies were performed over the inferior iris. These were placed so they would be overlying the cysts. It was possible to visualize the cysts collapsing immediately after treatment. Topical timolol 0.5% was begun in the left eye and 2 weeks later the intraocular pressure measured 16 mm Hg in both eyes. Given the amount of disc damage it was elected to add timolol to the right eye also. Most recent clinical follow-up in July 2005 revealed a stable visual field. Intraocular pressures were stable at 11 mm Hg on timolol drops in each eye. The second case is of a 53-year-old woman who was noted to have a presenile localized cataract temporally in the right eye. UBM was requested to assess this area further (Fig. 4). An iris root cyst was identified that appeared to be contacting the peripheral lens. A localized increased reflectivity in the lens was noted that corre-
Fig. 1—Slit-lamp photograph of bulges above the pupil margin.
Fig. 3—Ultrasound biomicroscopy of multiple cysts in inferior angle.
Fig. 2—Ultrasound biomicroscopy of inferior angle showing large cyst.
Fig. 4—Ultrasound biomicroscopy of cyst touching peripheral lens.
Cases
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sponded with the cataract seen. The patient underwent an uncomplicated cataract extraction with intraocular lens implantation and achieved 6/6 vision postoperatively. Over the study period we had no clinical incidence of progressive cyst enlargement. Repeat UBMs were performed in 3 patients who were referred for a repeat study. One patient had a repeat UBM 4 times. In none of these cases was there evidence of cyst enlargement. There was only 1 familial case within the series. There was 1 mother and 1 adult daughter who both had multiple bilateral iridociliary cysts. Both were asymptomatic and had normal intraocular pressure. At our recommendation the other daughter had bilateral UBM performed and no cysts were identified. INTERPRETATION
Our understanding of iridociliary cysts has come a long way since the advent of UBM in the early 1990s. It appears that these are far more common than originally thought. Given the relatively young mean age of patients in our study and also in that of Kunimatsu,8 we suspect either these are congenital lesions or they developed early in life. They generally appeared to be nonprogressive. Cyst-related glaucoma occurred in patients that had multiple areas of angle compromise due to large cysts. Despite an interesting case report,4 familial occurrence of cystic angle-closure glaucoma appears to be rare. It should be noted that glaucoma is probably over-represented in our study because we receive many referrals from a high volume glaucoma clinic located on site. In terms of glaucoma treatment, there appears to be a role for laser iridotomy in patients whose cysts contribute to angle compromise. We had no incidence of diplopia when iridotomy was performed overlying iris cysts. This theoretically should not be possible, as the pigmented posterior wall of the cyst remains intact. Lasering of the cyst wall directly through the pupil orifice is technically more difficult and may result in lens complications. It is our impression that iridociliary cysts generally do not enlarge. Cyst-related angle-closure glaucoma probably occurs when age-related chamber shallowing further compromises an angle already narrowed by cysts. Additional studies would be needed to confirm this. We make the following recommendations for patient follow-up on the basis of our study results and a review of recent papers on the subject. Patients referred for UBM who are found to have an iridociliary cyst should
have 360° scanning in the indicated eye. Consideration should be given to scanning both eyes. This helps identify any potential angle compromise in either eye. Patients with multiple bilateral cysts that compromise the angle should be followed as glaucoma suspects and treated as required. Patients with no or less than 1 clock hour of angle narrowing should not require follow-up. Ultrasound biomicroscopy should be considered in atypical cases of narrow-angle glaucoma. This will help differentiate cases of cystic angle closure. Laser iridotomy overlying the cysts and (or) peripheral iridotomy are effective treatments. REFERENCES 1. Rosen E, Rosen R. Ciliary body cysts. Eye Ear Nose Throat Mon 1971;50:288–93. 2. Pavlin CJ, Foster FS. Ultrasound Biomicroscopy of the Eye. New York, NY: Springer-Verlag; 1995. 3. Marigo FA, Esaki K, Finger PT, et al. Differential diagnosis of anterior segment cysts by ultrasound biomicroscopy. Ophthalmology 1999;106:2131–5. 4. Vela A, Rieser JC, Campbell DG. The heredity and treatment of angle-closure glaucoma secondary to iris and ciliary body cysts. Ophthalmology 1984;91:332–7. 5. Lois N, Shields CL, Shields JA, Mercado G. Primary cysts of the iris pigment epithelium. Clinical features and natural course in 234 patients. Ophthalmology 1998;105:1879–85. 6. Fine N, Pavlin CJ. Primary cysts in the iridociliary sulcus: Ultrasound biomicroscopic features of 210 cases. Can J Ophthalmol 1999;34:325–9. 7. Augsburger JJ, Affel LL, Benarosh DA. Ultrasound biomicroscopy of cystic lesions of the iris and ciliary body. Trans Am Ophthalmol Soc 1996;94:259–71. 8. Kunimatsu S, Araie M, Ohara K, Hamada C. Ultrasound biomicroscopy of ciliary body cysts. Am J Ophthalmol 1999;127: 48–55. 9. Azura-Blanco A, Spaeth GL, Araujo SV, Augsburger JJ, Terebuh AK. Plateau iris syndrome associated with multiple ciliary body cysts. Report of three cases. Arch Ophthalmol 1996;114:666–8. 10. Tanihara H, Akita J, Honjo M, Honda Y. Angle closure caused by multiple, bilateral iridociliary cysts. Acta Ophthalmology Scand 1997;75:216–7. 11. Kuchenbecker J, Motschmann M, Schmitz K, BehrensBaumann W. Laser iridocystotomy for bilateral acute angleclosure glaucoma secondary to iris cysts. Am J Ophthalmol 2000;129:391–3. 12. McWhae JA, Crichton ACS, Rinke M. Ultrasound biomicroscopy for the assessment of zonules after ocular trauma. Ophthalmology 2003;110:1340–3. Key words: glaucoma, angle closure, cataract
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