To report the intraoperative performance and postoperative outcomes of the Cionni-modified capsule tension ring (CTR) implantation in eyes with subluxated lenses.
Prospective, observational case series.
This study was carried out at Iladevi Cataract & IOL Research Centre, Ahmedabad, India. The study population comprised 41 eyes with subluxated lenses that underwent lens extraction, capsular bag fixation with modified CTR, and in-the-bag single-piece AcrySof intraocular lens (IOL) implantation. Main outcome measures were intraoperative performance and postoperative best-corrected visual acuity (BCVA), IOL centration, and complications.
The mean age was 29.46 ± 16.16 years (3-68 years). Mean extent of subluxation was 6.1 ± 1.0 clock hours. Preoperatively, vitreous was detected in the anterior chambers of 5 eyes (12.2%). Two-port anterior chamber vitrectomy was performed in 2 eyes. Mean follow-up was 45.8 ± 2.9 months. Mean preoperative BCVA was 0.66 ± 0.22 logMAR (35 eyes). Mean postoperative BCVA at final follow-up was 0.33 ± 0.21 logMAR (41 eyes) ( P < .001). BCVA improved in 35 eyes (85.4%) at the last follow-up. In 3 eyes (7.3%) IOL decentration was noted and repositioning was required in 2 eyes. Posterior capsule opacification developed in 14 eyes (34.2%); 12 eyes (29.3%) required Nd:YAG capsulotomy. Other complications included cystoid macular edema in 1 eye (2.4%), posterior synechiae in 1 eye (2.4%), and retinal detachment in 1 eye (2.4%).
In-the-bag implantation of a Cionni-modified CTR with IOL appears to be a safe option in eyes with subluxated cataract, ensuring a stable IOL with few complications.
The loss of significant zonular support presents many challenges for successful lens removal and intraocular lens (IOL) implantation. Surgeons can choose from a plethora of options while carrying out IOL implantation. This problem can be handled by using several endocapsular supporting devices. The introduction of endocapsular stabilizing devices has changed the surgical management of eyes with subluxated lens removal, allowing in-the-bag IOL implantation. In recent studies, it has been observed that the use of the Cionni-modified capsule tension ring (CTR) can help in the management of zonular dialysis in both adult and pediatric eyes. However, several potential sequelae might affect the long-term outcomes, including posterior capsule opacification (PCO) along with postoperative shrinkage and deformity of the capsular bag, a propensity for inflammation, and the probability of progressive zonular weakness. We are unaware of previous reports prospectively evaluating the long-term outcomes following Cionni ring implantation. We designed this prospective study with the objective of analyzing the intraoperative performance and long-term postoperative outcomes following Cionni-modified CTR and in-the-bag IOL implantation in eyes with subluxated lenses.
Patients and Methods
We prospectively enrolled 46 consecutive eyes with subluxation of crystalline or cataractous lens between January 30, 2003 and December 30, 2007. Zonular weakness and lens subluxation with diverse etiologies, including trauma, were included. Eyes with gross anterior or posterior dislocation were excluded. The evaluation of different etiologies of subluxation was based on the patients’ medical history and verified by the physician. A detailed examination under anesthesia (EUA) was performed for every child, both preoperatively and at each follow-up visit. Preoperatively, the refractive error and visual acuity were recorded. Slit-lamp evaluation was carried out to assess anterior chamber depth, the presence or absence of vitreous in the anterior chamber, extent of subluxation in clock hours, and zonular integrity. Cataract density was graded according to the Emery and Little classification: intraocular pressure (IOP) was measured with Goldmann/Perkins applanation tonometer (Reichert, Depew, New York, USA). A detailed retinal evaluation, including B-scan ultrasound (Quantel, Zurich, Switzerland), when indicated, was performed. Axial length was measured using the IOL Master (Carl Zeiss, Jena, Germany) or immersion ultrasound (Ocuscan; Alcon, Laboratories, Fort Worth, Texas, USA). Anterior chamber depth was measured using optical coherence biometry (IOL Master; Zeiss) or immersion ultrasound biometry (Ocuscan; Alcon).
Preoperatively, mydriasis was achieved with cyclopentolate 1% eye drops and phenylephrine 10% eye drops. In children, homatropine 1% eye drops were used to achieve dilation. A single surgeon (A.R.V.) performed the surgery using peribulbar anesthesia in adults and general anesthesia in children. A scleral pocket (2 × 2 mm in size) was created in the area of maximum zonular dehiscence, 1.5 mm behind the limbus. Then 2 paracentesis incisions were made and dispersive ophthalmic viscosurgical device (OVD), injection Viscoat (Alcon), was injected in the area of zonular dialysis to tamponade the vitreous face. A temporal single-plane limbal incision (2.2 or 2.8 mm) was preferred irrespective of the site of subluxation. A 26-gauge needle or a 15-degree slit knife was used to initiate a puncture in the anterior capsule in cases of extreme zonular weakness, which was then completed using the Uttrata forceps. Flexible iris retractors (Grieshaber & Co AG, Kennesaw, Georgia, USA) were used to engage the capsulorrhexis edge in order to stabilize the capsular bag in the area of zonular weakness in all cases. Thorough but careful multiquadrant hydrodissection was performed. Phacoemulsification was performed using either a Legacy 20000 Phacoemulsifier (Alcon) or an Infiniti Vision System (Alcon) with a power appropriate to the grade of cataract and low aspiration parameters with a standardized surgical technique described elsewhere. The presence of residual vitreous in the anterior chamber was managed with 2-port anterior vitrectomy. In pediatric eyes, the lens material was aspirated using bimanual irrigation/aspiration (I/A) with low aspiration parameters. After cortex removal, the capsular bag was inflated with high-viscosity OVD (Healon GV). A Cionni ring was then implanted in the capsular bag. As a first step, a 9-0 or 10-0 polypropylene monofilament nonabsorbable suture, double-armed with 2 curved needles, was passed through the eyelet on the Cionni element, outside the eye. Between January 2002 and February 2003, both 10/0 and 9/0 sutures were used. However, the use of 10-0 Prolene suture was discontinued after February 2003.
The Cionni ring was implanted through the main incision into the capsular bag. The ring was dialed into position so that the fixation eyelet lay in the area of maximum zonular weakness, ensuring that the eyelet was positioned anterior to the capsulorrhexis. A corneal stab incision was made opposite the scleral flap. The curved needle of the Prolene suture was introduced into the anterior chamber through this stab incision. A bent 26-gauge needle was passed through the scleral pocket to fetch this curved needle outside the eye. Similarly, the second needle was passed along the same track. The sutures were tightened and tied to center and stabilized the capsular bag. The capsulorrhexis was enlarged by an initial small and definitive large rhexis (I&D rhexis) wherever required. A single-piece SN60AT/SN60WF AcrySof IOL (Alcon) was implanted in the capsular bag. The overlying conjunctiva, 2 paracentesis incisions, and the main incision were sutured. Residual OVD was removed and 0.1 to 0.2 mL of intracameral 0.5% pilocarpine nitrate was used to constrict the pupil. This also ensured the absence of vitreous in the anterior chamber. Finally, 0.1 mL of 1% vancomycin was injected intracamerally. Postoperatively, all patients were given 1% prednisolone acetate eye drops along with 0.3% ciprofloxacin eye drops and 0.5% timolol maleate eye drops. Systemic corticosteroid (oral prednisolone) was given to all patients in tapering doses of 1 mg/kg body weight per day.
Postoperatively, patients were examined on the first postoperative day, at 1 month, every 3 months during the first year, and every 6 months thereafter for 4 years. Additional follow-up was tailored to meet the patients’ specific needs. At every visit, the following parameters were noted: best-corrected visual acuity (BCVA), IOP, IOL centration, PCO, and other complications. A clinically and geometrically well-centered IOL was defined as no optic edge identified in undilated pupils. A clinically well-centered but geometrically decentered IOL was defined by the difference in the distance from the optic edge to the limbus on both sides of the IOL. BCVA values were recorded and categorized in terms of Snellen equivalent as 20/40 or better and 20/60 to 20/200 and further converted into logMAR values for statistical analysis. The change in mean BCVA values from the preoperative to the postoperative period at each follow-up was analyzed. We also analyzed whether there was any difference in postoperative outcomes in eyes with traumatic vs nontraumatic subluxation.
We excluded 5 of 46 eyes from the analysis, as we could not implant the Cionni ring. Thus we evaluated 41 eyes of 33 patients. The preoperative characteristics are described in Table 1 . The mean age of the 33 patients (28 male and 5 female) was 29.46 ± 16.16 years (3−68 years). Bilateral surgery was performed in 8 patients and unilateral surgery in 25. The extent of subluxation ranged from 3−7 clock hours, with mean extent of subluxation being 6 clock hours ( Figure 1 ). Vitreous was detected in the anterior chambers of 5 of the 41 eyes (12.2%). Fundus examination revealed lattice degeneration in 1 eye, which was subjected to laser prophylaxis before cataract surgery. Three eyes had myopic degeneration. Five eyes with IOP values of 24, 29, 23, 24, and 46 mm Hg had primary open-angle glaucoma before cataract surgery. Trabeculectomy had been previously carried out before cataract surgery in 1 of these 5 eyes, while the remaining 4 were prescribed antiglaucoma medication. IOP was well controlled prior to the commencement of surgery.
|Sr No||Sex||Age, y||Laterality||Eye||Etiology||Type||Grade||Extent Clock Hours||ACD||IOP||Suture Prolene||IOL||Surgical Procedure|
|25||M||12||Unilateral||OD||Idiopathic||Clear lens||0||7||3.5||18||9-0||SN60AT 18D||I/A/IOL/MCTR|
|28||M||4||Bilateral||OD||Marfan||Clear lens||0||7||3.64||12||9-0||SN60AT 19D||I/A/IOL/MCTR|
|29||M||4||OS||Marfan||Clear lens||0||7||3.53||16||9-0||SN60AT 18.5D||I/A/IOL/MCTR|
|31||8||OS||Congenital||Clear lens||0||7||3.53||18||9-0||SN60AT 14D||I/A/IOL/MCTR|
|35||M||17.0||Unilateral||OD||Congenital||PSC||0||7||2.85||12||9-0||SN60WF 25 D||I/A/IOL/MCTR|
|36||M||3.0||Unilateral||OD||Marfan||Clear lens||0||7||3.09||18||9-0||SN60WF 18D||I/A/IOL/MCTR|
|37||M||10.0||Bilateral||OD||Marfan||Clear lens||0||7||3.1||17||9-0||SA60AT 12.5 D||I/A/IOL/MCTR|
|38||10.0||OS||Marfan||Clear lens||0||7||3||14||9-0||SA60AT 12 D||I/A/IOL/MCTR|
|39||M||54.0||Unilateral||OD||Idiopathic||Nuclear+PSC||4||3||2.8||12||9-0||SN60WF 18 D||PE/IOL/MCTR|
A continuous curvilinear capsulorrhexis (CCC) could be performed in all cases. Iris retractors were used to stabilize the capsular bag and when needed. A 2-port anterior chamber vitrectomy was performed in 2 eyes with traumatic subluxation prior to anterior capsulorrhexis. Endocapsular phacoemulsification was performed in 28 eyes (68.3%) while bimanual I/A was performed in 13 eyes (31.7%). In 12 eyes, I&D rhexis was performed. The Cionni CTR could be implanted in the bag in all eyes without causing any further zonular dialysis or capsular tears. It was fixed to the sclera using 10−0 Prolene sutures in 2 eyes (4.9%) and 9−0 Prolene sutures in 39 eyes (95.1%) ( Table 1 ). A single-piece AcrySof IOL was implanted in the capsular bag ( Table 1 ). At the end of the surgery, all the eyes had a well-centered IOL. A 2-port anterior chamber vitrectomy was also performed during surgery in 3 eyes with traumatic subluxation, of which 1 eye had to undergo vitrectomy after plaque peeling because of anterior vitreous face disturbance. In another 2 eyes, after Cionni ring and IOL implantation and removal of residual OVD and after 0.1 to 0.2 mL of intracameral 0.5% pilocarpine nitrate was used to constrict the pupil, a vitreous strand was identified attached to the pupil. The strand was irregular and had to undergo 2-port anterior vitrectomy; later, the pupil was round and well constricted.
Intraoperatively, we had to exclude 5 of 46 eyes. Of these, 2 eyes of 2 patients with Marfan syndrome had to be excluded because of incomplete anterior capsulorrhexis and these eyes subsequently had to undergo pars plana lensectomy and vitrectomy and scleral fixation of the IOL. In another 3 eyes, we had to explant the Cionni ring during the process of enlarging anterior capsulorrhexis because of peripheral extension, and subsequently the capsular bag was removed by performing a 2-port limbal anterior vitrectomy and scleral fixation of the IOL was done. The mean age of these 5 patients was 26.4 ± 16.5 years (10−44 years) and the extent of subluxation was 5.4 ± 1.56 clock hours (4−7 clock hours).
The mean follow-up duration was 45.8 ± 2.9 months (range 40−48 months). The postoperative visual acuity and complications have been mentioned for all eyes in Table 2 . The mean preoperative BCVA was +0.66 ± 0.22 logMAR. The distribution of postoperative BCVA in terms of Snellen equivalent at every follow-up is shown in Table 3 . The mean postoperative BCVA at the final follow-up was significantly better than the preoperative value in 35 of 41 eyes (85.4%) ( P < .001). Of these 35 eyes, 3 eyes (7.30%) initially deteriorated but then improved at final follow-up. Further, an overall assessment of change in vision to 4 years postoperatively is provided in Table 4 . The IOL remained centered in 38 of 41 eyes (92.7%) ( Figure 2 ). Postoperative IOL decentration was observed in 3 of 41 eyes (7.3%) at a mean duration of 25 ± 8.4 months (range 1−46 months). All these eyes had a preoperative zonular weakness ranging from 4 to 7 clock hours with Marfan syndrome. However, surgery was uneventful in all these eyes. Two eyes had decentration of the capsular bag–IOL complex, which required resuturing of the Cionni CTR-IOL complex. After refixation, the IOL remained centered until the last follow-up. One eye had decentration of the IOL 46 months after surgery, but the patient had no visual complaints, and surgical intervention was not required.
|Sr No||Laterality||Eyes||Follow-up, Months||Visual Acuity (Snellen’s): Preoperative to 4-years Postoperative||Postoperative Complications|
|Pre op||1 Month||1 Year||2 Years||3 Years||4 Years|