peripheral iris erosions associated with pediatric intraocular lens implants David A. Hiles, M.D. Pittsburgh, Pennsylvania
Peripheral iris erosions have recently been encountered as a postoperative complication of intraocular lens (IOL) implantation in adults.!,2Jt is the purpose of this paper to report this complication in children who have received IOL implants. SUBJECTS AND METHODS The author's series of 120 pediatric IOLs implanted over the past five years was reviewed. Seventynine patients had infantile and 41 had traumatic cataracts. The average age at implantation was 6.7 years and ranged from four months to 24 years of age. Eight of these implant patients were discovered to have erosion of the midperiphery of the iris adjacent to the rim of the IOL haptic (Fig. 1). Their records were further reviewed and are summarized in this report.
RESULTS The complication of peripheral iris erosion adjacent to the circular rim of the IOL occurred in eight (6.7%) of this author's 120 pediatric IOL implant patients. The ages of these eight patients at implantation ranged from nine to 76 months with a mean of 36 months: one half of the patients were under two years of age (Table 1). Two patients developed traumatic cataracts following penetrating corneal injuries. Both also had adherent iris leukomas which were severed at the time of IOL implantation. The remainder of the patients had infantile cataracts unassociated with other ocular anomalies. All of the patients were Caucasian: four had blue eyes and four had brown eyes. All but one patient had a combined phacoemulsification of the cataract and IOL implantation. One patient (number 1) experienced posterior capsule rupture and vitreous loss at the time of implantation. Four patients received 2-100p iridocapsular IOLs and four patients received 2-100p iris suture IOLs. Three manufacturers were represented. Five IOLs had platinum or platinum-iridium loops, one had titanium loops and two had polypropylene loops. Iris synechiae formation onto the haptic rim at the site of future iris erosions was observed in seven of the eight patients (Fig. 2). They occurred from the first postoperative month to the twenty-fourth month with a mean of 13 months. The duration from implantation to the occurrence of actual iris erosions ranged from 17 to 43 months with a mean of 25 months. All of the erosions were discovered during routine postoperative examinations.
Fig. I (Hiles). Nasal iris erosion with exposure of metal loops following infantile cataract extraction and IOL implantation. Iris sphincter erosion is also present.
From the Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania. This study was supported in part by grants to the Fight for Sight Children's Eye Clinic of the Eye and Ear Hospital of Pittsburgh, Pennsylvania, by Fight for Sight, Inc., New York, New York. Presented at the U.S. IOL Symposium in Los Angeles, April 1979. Reprint requests to Dr. Hiles, 3518 Fifth Ave., Pittsburgh, PA 15213. 210
Fig. 2 (Hiles). Anterior synechia extending from the iris onto the IOL haptic.
AM INTRA·OCULAR IMPLANT SOC J-VOL. V, JULY 1979
Table l. Summary of findings in patients with peripheral iris erosion.
Patient
Type of Cataract
Type of Implant Surgery
Age of Patient Receiving Implant (months)
Preoperative Complications
PostPost-Implant PostOccurrence of Implant Extent of Implant Synechiae Occurrence Iris Erosion Time of Formation to of Iris Discission(s) IOL Haptic Erosion (clock hours (months) (months) (months) of haptic rim)
19
6:00-11 :30 (Fig. I)
16
20
4:00-5:30
17
16
17
2:00-4:30
3,4,20
3
30
5:30-7:00
3,24
24
24
2:00-6:00
3
19
43
9:30-11:00
26
5:30-6:30
20
4:00-6:00
Infantile
Phacoemulsification and IOL implantation
9
2
Infantile
Phacoemulsification and IOL implantation
13
1,6
3
Infantile
Secondary IOL implantation
13
4
Traumatic
Phacoemulsification and IOL implantation
22
5
Infantile
Phacoemulsification and IOL implantation
37
6
Traumatic
Phacoemu Isification and IOL implantation
73
7
Infantile
Phacoemulsification and IOL implant ation
76
8
Infantile
Phacoem u lsi fication and IOL implantation
47
Penetrating Corneal Scar; Adherent Leukoma
Penetrating Corneal Scar; Adherent Leukoma
DISCUSSION The mechanism of peripheral iris erosion appears to be two-fold. In seven of the eight patients, either small pointed iris synechiae had formed over the IOL haptic rim and onto the anterior lens face, or narrow mem branes had formed from rim to rim over the anterior surface of the IOL. Both produced areas of iris fixation to the IOL rim. With the passage of time, the constant chafing of the iris stroma at the IOL haptic rim during iris dilatation and constriction movements severed the iris synechiae or membranes, creating an area of iris atrophy and eventually a through-and-through erosion of the iris stroma and pigment epithelium. Drews, Smith and Okun 3 have demonstrated by scanning electron microscopy that some IOLs have or develop rough edge defects in vivo. Abrasion from these IOL haptic rims creates iris irritation which leads to synechiae formation and later to erosion through the stroma and pigment epithelium. The IOL loops may be observed through the erosion to lie in their proper positions posterior to the iris. The
I, 17,26
II
rounded extremities of the IOL loops remain peripheral to the erosion and do not appear to be a factor in its creation. The incidence of this complication in the original series of 120 implants is 6.8%. The shortest time elapsing between IOL implantation and iris erosion was 17 months. For thesubgroup of 80 patients with a 17-month or longer follow-up, the incidence of iris erosion increases to 10%. The gradual evolution of this process is characterized by the lack of observable iris and anterior chamber reaction and by the lack of hyphemas. All of the erosions were first observed on routine postoperative visits and were unnoticed by the patients or their parents. Glaucoma has not occurred in any of these eyes. The patients therefore do not have the uveitis-glaucoma-hyphema syndrome described by Ellingson. 4 There does not appear to be a direct relationship between the heavier metal loop IOLs and peripheral iris erosion since two patients with polypropylenelooped IOLs have also experienced this problem.
AM INTRA-OCULAR IMPLANT SOC J-VOL. V, JULY 1979
211
No treatment has been instituted for any of these patients, since all of the eyes are without signs of ocular irritation. IOL removal is not suggested unless problems arise. A prophylactic severing of iris synechiae to or over the haptic and optic might be considered to eliminate this complication, but this practice has not been undertaken in any of the patients to date.
SUMMARY Eight children in whom 2-100p iridocapsular lenses or 2-100p iris suture lenses were implanted have exhibited peripheral iris erosion adjacent to the IOL haptic, through the iris stroma, and eventually through the iris pigment epithelium. The process appears to be very gradual and these pat"ients have exhibited no signs of iris irritation or hyphema. No treatment has been instituted. REFERENCES I. Dulaney DD: IOLs and iris erosion. Am Intra-Ocular Implant Soc] 4:120, 1978 2. Dulaney DD: IOLs and iris erosion. Am Intra-Ocular Implant Soc] 4:208, 1978 3. Drews RD, Smith ME, Okun N: Scanning electron microscopy of intraocular lenses. Ophthalmol 85:417, 1978 4. Ellingson IT: Complications with the Choyce Mark VIII anterior chamber lens implant (uveitis-glaucoma-hyphema). Am Intra-Ocular Implant Soc] 3:199, 1977
212
AM INTRA-OCULAR IMPLANT SOC J-VOL. V, JULY 1979
Peripheral iris erosions have recently been encountered as a postoperative complication of intraocular lens (IOL) implantation in adults.!,2Jt is the purpose of this paper to report this complication in children who have received IOL implants. SUBJECTS AND METHODS The author's series of 120 pediatric IOLs implanted over the past five years was reviewed. Seventynine patients had infantile and 41 had traumatic cataracts. The average age at implantation was 6.7 years and ranged from four months to 24 years of age. Eight of these implant patients were discovered to have erosion of the midperiphery of the iris adjacent to the rim of the IOL haptic (Fig. 1). Their records were further reviewed and are summarized in this report.
RESULTS The complication of peripheral iris erosion adjacent to the circular rim of the IOL occurred in eight (6.7%) of this author's 120 pediatric IOL implant patients. The ages of these eight patients at implantation ranged from nine to 76 months with a mean of 36 months: one half of the patients were under two years of age (Table 1). Two patients developed traumatic cataracts following penetrating corneal injuries. Both also had adherent iris leukomas which were severed at the time of IOL implantation. The remainder of the patients had infantile cataracts unassociated with other ocular anomalies. All of the patients were Caucasian: four had blue eyes and four had brown eyes. All but one patient had a combined phacoemulsification of the cataract and IOL implantation. One patient (number 1) experienced posterior capsule rupture and vitreous loss at the time of implantation. Four patients received 2-100p iridocapsular IOLs and four patients received 2-100p iris suture IOLs. Three manufacturers were represented. Five IOLs had platinum or platinum-iridium loops, one had titanium loops and two had polypropylene loops. Iris synechiae formation onto the haptic rim at the site of future iris erosions was observed in seven of the eight patients (Fig. 2). They occurred from the first postoperative month to the twenty-fourth month with a mean of 13 months. The duration from implantation to the occurrence of actual iris erosions ranged from 17 to 43 months with a mean of 25 months. All of the erosions were discovered during routine postoperative examinations.
Fig. I (Hiles). Nasal iris erosion with exposure of metal loops following infantile cataract extraction and IOL implantation. Iris sphincter erosion is also present.
From the Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania. This study was supported in part by grants to the Fight for Sight Children's Eye Clinic of the Eye and Ear Hospital of Pittsburgh, Pennsylvania, by Fight for Sight, Inc., New York, New York. Presented at the U.S. IOL Symposium in Los Angeles, April 1979. Reprint requests to Dr. Hiles, 3518 Fifth Ave., Pittsburgh, PA 15213. 210
Fig. 2 (Hiles). Anterior synechia extending from the iris onto the IOL haptic.
AM INTRA·OCULAR IMPLANT SOC J-VOL. V, JULY 1979
Table l. Summary of findings in patients with peripheral iris erosion.
Patient
Type of Cataract
Type of Implant Surgery
Age of Patient Receiving Implant (months)
Preoperative Complications
PostPost-Implant PostOccurrence of Implant Extent of Implant Synechiae Occurrence Iris Erosion Time of Formation to of Iris Discission(s) IOL Haptic Erosion (clock hours (months) (months) (months) of haptic rim)
19
6:00-11 :30 (Fig. I)
16
20
4:00-5:30
17
16
17
2:00-4:30
3,4,20
3
30
5:30-7:00
3,24
24
24
2:00-6:00
3
19
43
9:30-11:00
26
5:30-6:30
20
4:00-6:00
Infantile
Phacoemulsification and IOL implantation
9
2
Infantile
Phacoemulsification and IOL implantation
13
1,6
3
Infantile
Secondary IOL implantation
13
4
Traumatic
Phacoemulsification and IOL implantation
22
5
Infantile
Phacoemulsification and IOL implantation
37
6
Traumatic
Phacoemu Isification and IOL implantation
73
7
Infantile
Phacoemulsification and IOL implant ation
76
8
Infantile
Phacoem u lsi fication and IOL implantation
47
Penetrating Corneal Scar; Adherent Leukoma
Penetrating Corneal Scar; Adherent Leukoma
DISCUSSION The mechanism of peripheral iris erosion appears to be two-fold. In seven of the eight patients, either small pointed iris synechiae had formed over the IOL haptic rim and onto the anterior lens face, or narrow mem branes had formed from rim to rim over the anterior surface of the IOL. Both produced areas of iris fixation to the IOL rim. With the passage of time, the constant chafing of the iris stroma at the IOL haptic rim during iris dilatation and constriction movements severed the iris synechiae or membranes, creating an area of iris atrophy and eventually a through-and-through erosion of the iris stroma and pigment epithelium. Drews, Smith and Okun 3 have demonstrated by scanning electron microscopy that some IOLs have or develop rough edge defects in vivo. Abrasion from these IOL haptic rims creates iris irritation which leads to synechiae formation and later to erosion through the stroma and pigment epithelium. The IOL loops may be observed through the erosion to lie in their proper positions posterior to the iris. The
I, 17,26
II
rounded extremities of the IOL loops remain peripheral to the erosion and do not appear to be a factor in its creation. The incidence of this complication in the original series of 120 implants is 6.8%. The shortest time elapsing between IOL implantation and iris erosion was 17 months. For thesubgroup of 80 patients with a 17-month or longer follow-up, the incidence of iris erosion increases to 10%. The gradual evolution of this process is characterized by the lack of observable iris and anterior chamber reaction and by the lack of hyphemas. All of the erosions were first observed on routine postoperative visits and were unnoticed by the patients or their parents. Glaucoma has not occurred in any of these eyes. The patients therefore do not have the uveitis-glaucoma-hyphema syndrome described by Ellingson. 4 There does not appear to be a direct relationship between the heavier metal loop IOLs and peripheral iris erosion since two patients with polypropylenelooped IOLs have also experienced this problem.
AM INTRA-OCULAR IMPLANT SOC J-VOL. V, JULY 1979
211
No treatment has been instituted for any of these patients, since all of the eyes are without signs of ocular irritation. IOL removal is not suggested unless problems arise. A prophylactic severing of iris synechiae to or over the haptic and optic might be considered to eliminate this complication, but this practice has not been undertaken in any of the patients to date.
SUMMARY Eight children in whom 2-100p iridocapsular lenses or 2-100p iris suture lenses were implanted have exhibited peripheral iris erosion adjacent to the IOL haptic, through the iris stroma, and eventually through the iris pigment epithelium. The process appears to be very gradual and these pat"ients have exhibited no signs of iris irritation or hyphema. No treatment has been instituted. REFERENCES I. Dulaney DD: IOLs and iris erosion. Am Intra-Ocular Implant Soc] 4:120, 1978 2. Dulaney DD: IOLs and iris erosion. Am Intra-Ocular Implant Soc] 4:208, 1978 3. Drews RD, Smith ME, Okun N: Scanning electron microscopy of intraocular lenses. Ophthalmol 85:417, 1978 4. Ellingson IT: Complications with the Choyce Mark VIII anterior chamber lens implant (uveitis-glaucoma-hyphema). Am Intra-Ocular Implant Soc] 3:199, 1977
212
AM INTRA-OCULAR IMPLANT SOC J-VOL. V, JULY 1979
