Evaluation of the first 100 consecutive PhacoFlex silicone lenses implanted in the bag through a self-sealing tunnel incision using the Prodigy inserter

We evaluated the performance of the PhacoFlex silicone lens with open polypropylene loops and the disposable Prodigy inserter in a series of 100 consecutive no-stitch cases. Loading the lens into the PRO-1A inserter model was easy, as was inserting it through a 4 x 4 mm self-sealing sclerocorneal tunnel incision. If the chamber was deep and the capsular fornix expanded, unfolding the polypropylene loops was safe and direct bag placement was always possible. If the capsular bag was insufficiently distended, however, the posterior loop tended to entangle with wrinkles in the posterior capsule, jeopardizing the capsule's integrity. With a round and well-centered 4 mm to 5 mm capsulorhexis, centration was good provided the lens was completely within the bag. Even with proper bag placement of the haptics, however, the optic occasionally decentered slightly and tilted because of secondary capture in the capsulorhexis opening. With an incomplete capsulorhexis or a jagged-edged capsulotomy, malpositioning was not uncommon. This was due to secondary displacement of one haptic into the sulcus or partial capture of the optic by the anterior capsule leaf. Because of the flexibility of the polypropylene loops, the lenses tended to decenter and tilt following capsular shrinkage.     

Security of capsular fixation: small-versus large-hole plate-hepatic lenses

PURPOSE: To assess the effect of relatively large positioning holes on the security of capsular bag fixation of plate-haptic silicone intraocular lenses (IOLs). SETTING: Center for Research on Ocular Therapeutics and Biodevices, Department of Ophthalmology, Storm Eye Institute, Medical University of South Carolina, Charleston, South Carolina, USA. METHODS: This study tested the hypothesis that larger holes allow ingrowth of lens material, fibrous tissue, or both through them, which helps fixate the lens more firmly in the capsular bag. Five rabbits had bilateral continuous curvilinear capsulorhexis, phacoemulsification, and implantation of a plate-haptic silicone IOL. An IOL with a small, round positioning hole (Staar AA-4203V) was implanted in the right eye in each rabbit, and a large-hole IOL (Staar AA-4203VF) was implanted in the left eye. After 2 months, all rabbits were killed. The force required to extract one haptic from the capsular bag was measured with a digital force meter. All eyes had histopathological analysis. RESULTS: It was slightly more difficult to extract a large-hole IOL from the capsular bag, although this trend was not statistically significant. However, histopathological analysis consistently showed 360 degree synechia formation through the holes, showing that the IOL could be securely fixed in position. CONCLUSIONS: Proliferation of lens epithelial cells through a large positioning hole in a plate-haptic silicone IOL may improve the long-term security of capsular bag fixation. This will help reduce the incidence of IOL decentration and dislocation.     

In memoriam John R Casely-Smith, D. Sc., M.D. (h.c.)

BACKGROUND: After curvilinear capsulorhexis in cataract surgery often a double-ring shape of the remaining capsular margins can be observed. In order to better understand this phenomenon we performed a histological study of excised capsules after continuous curvilinear capsulorhexis. METHODS: Ten anterior capsular specimens from cases with double-ring structure of the capsular margins after continuous curvilinear capsulorhexis (D-group) were examined light microscopically and compared with 10 normal cases (N-group) and 10 cases with pseudoexfoliation (P-group). Three cases from each group were also examined electron microscopically. RESULTS: A characteristic step formation in the capsular edges and in addition horizontal capsular splits in the border zone between the zonular lamella of the anterior capsule and the capsule proper could be demonstrated histologically in the D-group. CONCLUSIONS: There seems to be a weak point of the capsular tissue in the border zone between zonular lamella of the lens and the capsule proper. The superficial splits that we found histologically in this region might be a precursor or forme fruste of true exfoliation. The outward-directed traction force exerted by the zonular fibers seems to lead to further disruption in this weakened layer of the lens capsule during capsulorhexis, producing a double-ring contour of the capsular margins.     

Accommodation amplitude after lens refilling with injectable silicone by sealing the capsule with a plug in primates

OBJECTIVE: To restore accommodation in primate eyes by refilling the lens capsule with injectable silicone compounds. MATERIALS AND METHODS: Eight eyes of 8 monkeys (Macaca fascicularis) were treated by the lens refilling procedure. To prevent leakage of the injected liquid silicone before it polymerized in the capsule in vivo, a silicone plug for sealing the capsular opening was developed. After endocapsular phacoemulsification following an upper minicircular capsulorhexis, the plug was introduced into the capsulorhexis opening. A silicone mixture was injected into the capsular bag through the delivery tube of the plug. Automated refractometry was performed 1 week and 3 months after surgery. Accommodation amplitude was determined as the difference between the refractions before and 1 hour after topical application of 4% pilocarpine chloride. RESULTS: Five of 8 eyes could be refilled. In 4 of 5 eyes, refraction could be measured. Accommodation amplitude ranged from 1.0 to 4.5 diopters, with a mean of 2.3 +/- 1.3 diopters (8.0 +/- 2.0 preoperative values). At 3-month examination, thick posterior capsule opacification precluded refractometry in all eyes. CONCLUSIONS: The lens refilling procedure with the use of a silicone plug for sealing the capsular opening was feasible in primate eyes. The accommodation amplitude attained was a small fraction of the value before surgery. This may result from the loss of so-called intracapsular accommodation, ie, active participation of lens fiber cells in accommodation. However, since the obtained accommodation may be sufficient for near vision after cataract surgery, this lens refilling procedure warrants further study. Elucidation of the mechanism of intracapsular accommodation may also be necessary.     

Neurodevelopmental outcome at age two years amongst very low birth weight infants: results from a district general hospital

SCOPE OF THE STUDY: We studied the possibility to examine position and determination of IOL and capsular bag supporting ring. PATIENTS AND METHODS: We showed in ten human eyes the identification of capsular bag supporting ring (PMMA, 12,5 mm open diameter) and intraocular lenses (IOL, 13,5 mm diameter) and haptics by ultrasound biomicroscopy in radar and limbus parallel scans 12 to 18 months post operation. RESULTS: Both alloplastic implantates show typical sceems of reflection and could be differentiated by ultrasoundbiomicroscopy. In eyes with zonulolysis up to 6 hours a good centration of capsular bag supporting ring and IOL had been seen, with more zonulolyses a slight subluxation could been shown. CONCLUSION: Ultrasound biomicroscopy is a good method to determine the position of intraocular lens and capsular bag supporting ring.     

New classification of capsular block syndrome

PURPOSE: To propose a new classification of capsular block syndrome (CBS) to improve understanding of the etiology and provide effective treatment. SETTING: Shohzankai Medical Foundation, Miyake Eye Hospital, Nagoya, and Japanese Red Cross Society, Wakayama Medical Center, Wakayama, Japan. METHODS: Three groups of eyes with CBS were reviewed: eyes originally reported and diagnosed as having CBS; eyes experiencing CBS after hydrodissection and luxation of the lens nucleus; and eyes with CBS accompanying liquefied aftercataract or capsulorhexis-related lacteocrumenasia. RESULTS: In all 3 groups, the CBS occurred in eyes with a continuous curvilinear capsulorhexis (CCC). It was characterized by accumulation of a liquefied substance within a closed chamber inside the capsular bag, formed because the lens nucleus or the posterior chamber intraocular lens (IOL) optic occluded the anterior capsular opening created by the CCC. Depending on the time of onset, CBS can be classified as intraoperative (CBS seen at the time of lens luxation following hydrodissection), early postoperative (original CBS), and late postoperative (CBS with liquefied aftercataract or lacteocrumenasia). The etiology of the accumulated substance and the method of treatment are different in each type. CONCLUSION: Capsular block syndrome is a complication of cataract/IOL surgery that can occur during and after surgery. Correctly identifying the type of CBS is crucial to understanding the nature and effective treatment of this disorder.     

Severe capsulorhexis contracture after cataract surgery in myotonic dystrophy

A 42-year-old woman with myotonic dystrophy developed bilateral severe capsulorhexis contracture after uneventful phacoemulsification cataract surgery with implantation of 1-piece poly(methyl methacrylate) intraocular lenses (IOLs). The anterior capsular opening in her right eye constricted to a diameter of 0.7 mm, reducing visual acuity to counting fingers. Complete closure of the capsulorhexis with IOL encapsulation developed in her left eye, reducing visual acuity to hand movements. Surgical anterior capsulectomies restored visual acuity to 6/9 in both eyes. Myotonic dystrophy may predispose to the development of severe capsulorhexis contracture after cataract surgery.     

Fixation elements on plate intraocular lens: large positioning holes to improve security of capsular fixation

OBJECTIVE: This study aimed to evaluate in rabbit eyes the effects of large positioning holes in one-piece silicone plate-haptic intraocular lenses (IOLs) with respect to security of capsular bag fixation. Mechanical strength of capsular fixation is correlated with the histologic findings of regenerating lens material and fibrous tissue ingrowth through the positioning holes on silicone plate IOLs, comparing capsules implanted with large-hole style plate IOLs to fellow capsules implanted with small-hole style plate IOLs. DESIGN: The study design was a prospective, randomized, experimental study. PARTICIPANTS: A total of 40 fellow capsular bags from 20 New Zealand white rabbits were examined. Capsules implanted with conventional small-hole silicone plate IOLs were used as the control in all pairs of fellow capsules. INTERVENTION: Phacoemulsification and implantation of a silicone plate IOL with small positioning holes in one eye and implantation of a silicone plate IOL with large positioning holes in the fellow eye were measured. All rabbits were killed at 2 months. The force required to extract the IOLs from the capsular bag was measured. All capsular bags underwent histopathologic analysis. MAIN OUTCOME MEASURES: Extraction force measurements and histopathologic examination, comparing capsules implanted with small-hole plate IOLs with fellow capsules implanted with large-hole plate IOLs, were measured. RESULTS: The large-hole style IOL required significantly more force to extract from the capsular bag compared to the conventional small-hole style (P = 0.003). Histologically, proliferating lens epithelial material and fibrous tissue were observed growing through all of the large positioning holes (synechia formation) but not through any of the small positioning holes. CONCLUSIONS: Silicone plate IOLs with large positioning holes become affixed more firmly within the capsular bag compared to conventional small-hole plate IOLs. These findings suggest that large holes in silicone plate IOLs allow for superior capsular bag fixation. This should reduce the rates of decentration and dislocation.     

Spontaneous dislocation into the vitreous of a poly(methyl methacrylate) disc lens 9 years after surgery

A 76-year-old woman had sudden visual loss 9 years after an extracapsular cataract extraction with implantation of a poly(methyl methacrylate) disc intraocular lens (IOL) in the capsular bag. Slitlamp examination showed the disc IOL had luxated into the vitreous through a linear inferior opening in the capsular bag; the IOL lay on the retinal surface. A pars plana vitrectomy was performed. The vitreous cavity was filled with perfluorocarbon liquid, floating the IOL to behind the iris. The IOL was removed through a limbal incision, then another type of IOL was implanted in the ciliary sulcus using transscleral fixation. Thirty days after surgery, best corrected visual acuity (BCVA) was 20/20. At 2 months, total retinal detachment appeared with a large superior retinal dialysis. Another pars plana vitrectomy was performed and the scleral-fixated IOL removed through a limbal incision. Internal gas tamponade was used. The eye was left aphakic. Final BCVA was 20/25.     

Placement of a secondary foldable intraocular lens over a capsule remnant

A bilaterally aphakic patient received a silicone intraocular lens (IOL) over an intact capsular bag. The fellow eye had a large capsule rupture. Implantation of a 3-piece silicone IOL was attempted over the capsule remnant and achieved without complication. One year postoperatively, the IOL remained stable.     

Effect of capsulorhexis diameter on glare disability

PURPOSE: To determine whether the diameter of the anterior capsulorhexis has an effect on postoperative glare. SETTING: Sapir Medical Center, Meir Hospital, Kfar Saba, Israel. METHODS: Forty patients had extracapsular cataract extraction (manual or phacoemulsification) through an intact continuous curvilinear capsulorhexis (CCC) of various sizes. The CCC diameter was measured and the opacity of the anterior and posterior capsules was evaluated before and after dilation of the pupils. Glare test (Miller-Nadler glare tester) was performed with the eyelid in a normal position and after lid elevation. RESULTS: The diameter of the CCC ranged from 3.50 to 7.00 mm (mean 4.87 mm). The anterior capsule was always opaque in the area of contact with the IOL material. None was graded clear; 60% were graded as +3. Mean glare disability prior to pupil dilation was 12.1 +/- 8.8 (SD) and after dilation, 17.3 +/- 9.7. There was no correlation between glare disability and the diameter of the capsulorhexis, the width of the exposed opacified capsular ring, or the grading of capsule opacification (anterior and posterior). Dilation of the pupil significantly increased glare disability (P = .016), unrelated to CCC diameter. CONCLUSION: A CCC larger than 3.5 mm does not induce significant glare.     

Preliminary study of a new intraocular method in the diagnosis and treatment of Propionibacterium acnes endophthalmitis following cataract extraction

Late endophthalmitis, due to Propionibacterium acnes, developed in three patients following uncomplicated extracapsular cataract extraction and posterior chamber intraocular lens (PC-IOL) insertion. Cultures from the capsular bag yielded P. acnes in all three. With topical anesthesia and through an anterior chamber paracentesis, culture specimens were taken from and clindamycin irrigated into the capsular bag. Filtered 100% oxygen was introduced into the anterior chamber in two; the third also received an injection of gentamicin and dexamethasone into the capsular bag. After treatment, two patients received oral antibiotics; one received hyperbaric oxygen therapy. Visual acuity was improved and inflammation reduced in all three. However, after treatment, ocular toxic effects due to clindamycin were suspected in one. This approach offers several clear advantages, including topical anesthesia, outpatient management, elimination of the need for vitrectomy, and retention of the intraocular lens (IOL).     

Intracapsular foldable posterior chamber lens implantation in eyes with posterior capsule tears or zonular fiber instability

A surgical technique is described for foldable posterior chamber intraocular lens implantation in the capsular bag in the presence of a posterior capsule tear or weakened zonular fiber support. Haptics are compressed by suturing before endocapsular insertion, minimizing capsular and zonular fiber stress.     

Early central posterior capsular fibrosis in sulcus-fixated biconvex intraocular lenses

A series of 228 eyes implanted with one-piece all poly(methyl methacrylate) (PMMA) biconvex posterior chamber intraocular lenses was examined for posterior capsule opacification. One hundred forty-one eyes (61.8%) had opacification at an average postoperative period of 19.7 months. Seventy eyes (30.7%) developed an unusual form of early central posterior capsular fibrosis (ECPCF), which was confined to the capsulorhexis opening, sparing the peripheral aspect of the anterior and posterior capsules. Risk factors for developing this form of opacification were close apposition of peripheral anterior and posterior capsules caused by placing a posteriorly vaulted biconvex optic anterior to a capsulorhexis opening smaller than the optic diameter. This opacification occurred most often in cases of haptic fixation in the ciliary sulcus. The cumulative capsulotomy rate in this series was 5.26% at three months, 9.1% at 12 months, and 13.2% at 20 months. Of the ECPCF cases, 34.3% eventually required neodymium: YAG (Nd:YAG) laser capsulotomy; the capsulotomy rate for ECPCF was 4.8 times higher than that for Elschnig pearls. Early onset of ECPCF (average onset = 19.4 weeks) resulted in early Nd:YAG capsulotomy (average = 8.0 months after surgery). One-piece all-PMMA biconvex intraocular lenses may promote early central fibrosis of the posterior capsule if the lens optic is anterior to a capsulorhexis opening smaller than the optic diameter. The early onset of this form of opacification predisposes to earlier Nd:YAG capsulotomy with a higher risk of complications.     

Perineural invasion of the lower alveolar nerve by oral cancer: a follow-up study of 12 cases

The authors studied the intraocular pressure (IOP) changes after phacoemulsification with two different kinds of foldable silicone lens implantation using Healon GV as viscoelastic substance. One hundred patients undergoing cataract surgery were enrolled in this study. Inclusion criteria were: absence of ocular hypertension or glaucoma. Patients were randomly assigned to plate haptic (Silens PH, Domilens Chiron Vision, Lyon, France) or three-piece (CeeOntrade mark& ;920, Pharmacia spa, Milano, Italia) silicone intraocular lens (IOL) implantation. Following phacoemulsification and cortical aspiration, the capsular bag was reinflated with Healon GV. After foldable silicone IOL insertion residual Healon GV was removed from the anterior chamber. IOP was measured preoperatively and at 6, 24 h and 1 week postoperatively. Six hours postoperatively IOP was higher in the Silens PH group than in the CeeOn group (20. 85+/-5.42 vs. 18.88+/-2.95 mm Hg, p= 0.026). The difference was confirmed after 24 h (21.02+/-5.18 vs. 17.34+/-3.18 mm Hg, p < 0.01). Despite the medical treatment (acetazolamide 250 mg orally every 6 h), at the 24-hour control 2 eyes with plate haptic silicone lens showed IOP values higher than 30 mm Hg. Slitlamp examination showed in both eyes a shallowing of the anterior chamber together with the evidence of capsular bag hyperdistension and capsular block resulting from the occlusion of the circular anterior capsule opening by the plate haptic IOL. Residual Healon GV removal from the anterior chamber was performed. At 1-week control both eyes showed normalization of IOP. The use of a plate haptic silicone lens may be associated with a more consistent retention of Healon GV in the eye with trapping in the capsular bag. Retained viscoelastic may cause either trabecular meshwork blockage by viscoelastic substance or postoperative capsular bag hyperdistension, anteroplacement of the IOL optic and capsular block from occlusion of the circular anterior opening by the IOL optic.     

Reduction of cataract by plasma etching of intraocular lenses. An animal experiment study

BACKGROUND: We studied if a modification of the silicon intraocular lens (IOL) by plasma etching is able to promote a bonding of the IOL surface and the capsular bag which might inhibit proliferation and migration of lens epithelial cells. METHODS: Silicon-disc lenses (90D, Adatomed), as disposable for regular cataract surgery, were used. Their haptic surface was etched via the use of a SO2 plasma, leaving the optic unmodified. The experiments were done on dwarf rabbits to allow for tight apposition of IOL and bag. Nine rabbits underwent extracapsular lensectomy using propofol anaesthesia and phaco/clear cornea surgical technique. Six eyes each received either no, a regular or a modified IOL. After 11 weeks the eyes were enucleated. Capsular bag and IOL were digitized using a flatbed scanner with transparency adapter. The data obtained were calibrated against a densitometric standard. The densities of the various specimen were analyzed quantitatively using self designed software. RESULTS: In aphacic eyes no significant posterior capsule opacification (PCO) was detectable. In the same time-span the regular IOL had developed a dense, heterogenous PCO. The plasma-treated IOL showed, especially in the central areas, a significant reduction of PCO as compared to untreated IOL. CONCLUSION: The reduction of PCO could not be explained by adhesion of the IOL surface and the capsular bag, which would impair migration of lens epithelial cells and thereby PCO. Likewise, lower PCO may be related to improved hydrophilic properties of the surface-modified IOL.     

Bladder biofeedback for the treatment of refractory sensory urgency in adults

PURPOSE: Constriction of the pupil during phacoemulsification and intraocular lens (IOL) implantation in patients with diabetes mellitus was studied. METHODS: Before surgery a combination of 0.75% cyclopentolate and 2.5% phenylephrine was applied topically to the eyes of 32 patients with diabetes mellitus and 25 age-matched controls. Epinephrine was mixed with buffered saline solution and used during the surgery. The surgical procedure included capsulorhexis, phacoemulsification in the posterior chamber and implantation into the capsular bag of a heparine surface-modified poly(methyl metacrylate) IOL with an optic diameter of 5.0 mm. The durations of phacoemulsification and the whole surgical procedure were recorded. Measurements of the horizontal pupillary diameter were taken before surgery, after phacoemulsification and at the end of the surgery. RESULTS: There was no significant difference in pupil size between controls and the diabetic group before the operation. Surgically induced miosis after phacoemulsification and at the end of operation were significantly more pronounced in the diabetic group than in controls (p < 0.05) (p < 0.05). Phacoemulsification and the entire surgical procedure took significantly longer time when performed in the diabetic eyes (p < 0.05) (p < 0.05). CONCLUSION: We conclude from these data that constriction of the pupil during cataract surgery is more pronounced in diabetic eyes as compared to controls.     

Late reopening of fibrosed capsular bags to reposition decentered intraocular lenses

The infrequent postoperative complication of intraocular lens decentration in the presence of an intact fibrosed capsule has traditionally been treated with lens explantation and exchange for a sulcus-fixated lens. Many of these patients can be managed by reopening the fibrosed capsular bag and repositioning the lens within the bag. These cases can be performed quickly using topical anesthesia regardless of the time since the primary cataract procedure.     

Pupillary block after pupillary capture of an AcrySof intraocular lens

A 54-year-old man developed pupillary block resulting from pupillary capture 2 months after uneventful phacomulsification and AcrySof intraocular lens (IOL) implantation. The IOL was placed in the bag through a 6.0 mm continuous curvilinear capsulorhexis. The glaucoma was treated with intravenous drip infusion of a hyperosmotic diuretic, followed by peripheral iridectomy, iridocapsular synechiolysis, and IOL repositioning. The IOL loops were located completely in the bag. However, pupillary capture recurred 3 weeks after the surgery, at which time intraocular pressure was normal. The flexibility of the IOL optic and its large overall length and rigid, low-angulated loops were the probable causes for the recurrence of the pupillary capture. The IOL was exchanged for a sulcus-fixated, single-piece poly(methylmethacrylate) lens with 10 degree angulated loops. Pupillary capture did not recur during the follow-up.     

Phacoemulsification with a bevel-down phaco tip: phaco-drill

We present a technique for in situ lens nucleus emulsification using low phaco power and high vacuum, a continuous curvilinear capsulorhexis, and hydrodelineation. Emulsification is done with the phaco tip slanted down 30 or 45 degrees. Cutting and aspiration do not cause an undesirable energy loss. This technique can be combined with the nuclear chopping or divide and conquer methods because of its ability to drill and hold the nucleus. Posterior capsular rupture is prevented because the separated epinucleus acts as a barrier between the nucleus and the cortex. The low power used minimizes the energy transfer to the corneal endothelium. This technique is particularly useful in eyes with brunescent cataract.