Posterior Polar Cataract 

Updated: Feb 07, 2019
Author: Rachel A Scott; Chief Editor: Hampton Roy, Sr, MD 

Overview

Background

The existence of congenital cataracts has been known for more than 200 years. Documented by Duke-Elder, several subtypes are described; however, a posterior polar cataract is distinct from other forms of congenital lens opacities.[1]

A posterior polar cataract is a round, discoid, opaque mass (see the image below) that is composed of malformed and distorted lens fibers located in the central posterior part of the lens. This location is its most significant feature, in addition to its proximity to and possible adherence with the posterior capsule. Moreover, the capsule itself may be weakened. As such, posterior polar cataract removal is a challenge to the surgeon because of its adherence to or the associated weakness of the posterior capsule.

The posterior polar cataract is seen as a dense di The posterior polar cataract is seen as a dense discoid opacity. The central fibrous mass consists of degenerated lens fibers surrounded by several small globular vacuoles containing what appears as a refractile substance as well as some lens degenerative fiber material.

See What the Eyes Tell You: 16 Abnormalities of the Lens, a Critical Images slideshow, to help recognize lens abnormalities that are clues to various conditions and diseases.

Posterior polar cataract, a distinctive subtype of lens opacity, presents as an area of degenerative and malformed lens fibers that form an opacity in the central posterior subcapsular area of the lens. Often, this opacity is adherent to the lens capsule, thereby making uncomplicated surgical removal problematic.

Posterior polar cataract surgery is associated with an increased incidence of rupture of the posterior capsule. Only in recent times have the advances in control of fluidics and aspiration during phacoemulsification prompted various approaches to meet this surgical challenge.

History of the Procedure

Duke-Elder discusses the historical methods of congenital cataract extraction used prior to the modern introduction of phacofluidics.[1] He also mentions discission, linear extraction (which would now be described as irrigation/aspiration), as well as intracapsular cataract extraction.[1]

In addition, Duke-Elder discusses the association of "irregularities in the development of lens fibers" and attributes this concept to von Szily in 1938.[1]

Further, histologic examination has found this to be the case in posterior polar cataracts.[2, 3, 4] Moreover, genetic analysis using polymerase chain reaction–based tests have shown that this autosomal dominant anomaly has been associated with a recurrent 17 bp duplication on the 3(PITX3) gene on chromosome 10.[5]

The histologic changes of the malformed lens fibers are now recognized to be associated with an adherence of these degenerative lens fibers to an area of the weakened posterior capsule.

Therefore, the surgical approach must be aimed at reducing the stress on the weakened posterior capsule. For this reason, various approaches have been suggested, including limited hydrodissection, viscodissection, and posterior capsulorrhexis. Still, the reported rate of capsular rupture in the procedure is too high, sometimes 25% or more.

Problem

The surgical significance of a posterior subcapsular cataract is an association with and an adhesion of the lens opacity to the posterior capsule immediately subjacent to it.

The incidence of capsular tears in this subtype of cataract surgery can approach an unacceptably high percentage. Some surgeons find that the tears occur most often during cortical aspiration.

The goal during posterior polar cataract surgery is to remove the opacity without rupturing the posterior capsule. This can be accomplished by decreasing stress on the posterior capsule during all phases of the surgery. Several surgical solutions and approaches have been proposed, but a technique for uncomplicated and successful posterior polar cataract extraction continues to remain challenging and problematic.

Epidemiology

Frequency

The occurrence of posterior polar cataracts is rare; in fact, little is published on the specific incidence of posterior polar cataracts. Further, no standardized subtype specific study on this type of cataract has been conducted. In the Framingham Eye Study, little prevalence data for posterior polar cataracts are presented. However, it is well accepted that this is an infrequently encountered form of cataract and that the prevalence is very low. When seen, it is often as an inherited trait and is present in several members of the same family.

The population-based analysis of posterior polar cataract prevalence has been studied. In summary, 111 cases of posterior polar cataracts were found against 37,837 population controls without ocular defects.[6] Even among congenital cataracts, posterior polar cataracts are rare, accounting for approximately 7% of eyes among children undergoing congenital cataract surgery.[7]

Other population studies have not focused on the incidence of posterior polar cataracts. Most studies based data on the incidence of all types of cataracts, which were part of the focus of the Framingham Eye Study, but found mainly age-related cataracts, although posterior subcapsular opacities were reported to occur in the younger subjects of the group studies. The Framingham Eye Study did not specifically address the incidence of posterior polar cataracts as a separate group.[8] Other studies focused on incidence and etiology and nutrition.[9, 10]

Etiology

A posterior subcapsular cataract is a distinctive, often very sharply demarcated opacity, discoid in shape and adjacent and merging with the posterior capsule. This cataract represents degenerative lens fibers that have developed abnormally. The lens fibers are surrounded by globular structures that contain a highly refractile material. A weakness of and adhesion to the posterior capsule immediately subjacent to the area of cataract is also associated with this type of cataract.

The etiology of this congenital condition has been noted for many years. For some time, it has been recognized that posterior polar cataracts seemed to follow an autosomal dominant inheritance pattern with an occasional sporadic mutation. The direct cause of the lenticular fiber malformation during lens development has not been well understood.[11, 12, 13]

Genetic analysis by Addison and colleagues, as well as by Burdon and colleagues, however, has focused attention on a mutation on the PITX3 gene.[14, 15] This gene was found to control the development of the anterior segment of the eye. The duplication of the 17 base pairs in this gene apparently alters the normal development of the anterior segment, leading to a posterior polar cataract. The exact mechanism through which this pathology is produced remains unclear.

Recent advances in genomics techniques, such as single-nucleotide polymorphism (SNP) and microsatellite markers, have led to an increased understanding of the mechanism. A specific example, relating to the formation of posterior polar cataract, is detailed in a report from Berry et al.[16] This report describes a pedigree, comprising 4 generations of a family, with more than 6 members diagnosed with posterior polar cataract after full eye examinations at the Moorefields Eye Hospital cataract clinic. Further, a genome-wide linkage was then performed by single-nucleotide polymorphism and microsatellite markers. An autosomal dominant base pair deletion (542delC) mutation was noted in the homeobox of gene PITX3 in 10q. This is one of the transcription factors critical for normal lens induction and development. The authors found this base pair to co-segregate with all the affected family members with posterior polar cataract.

Mutations to alpha-B crystallin, a small heat shock protein encoded by the CRYAB gene, have also been linked to the development of posterior polar cataracts. One such mutation of alpha-B crystallin is a missense mutation that changes proline 20 to arginine (P20R).[17, 18] Normally, alpha-B crystallin helps inhibit stress-induced apoptosis. However, in human lens epithelial cells, this mutation results in diminished-apoptotic activity, providing a potential mechanism by which posterior polar cataracts develop.[17] The autosomal-dominant nature of this allele is described in a five-generation pedigree report, with the mutation found in all members with posterior polar cataracts and not found in the 10 unaffected members.[18] Other CRYAB mutations, D109H and R120G, have also been linked to posterior polar cataract formation.[19] That D109 and R120 interact during dimerization of alpha-B crystallin again highlights that alpha-B crystallin may play an important role in posterior polar cataract development in some families.

Because the understanding of posterior polar cataract, an autosomal dominant condition, is continually expanding, genetic counseling for the parents remains very important.

Pathophysiology

A posterior polar cataract has an autosomal dominant inheritance pattern. However, it has also been noted as a result of gene mutation.[14] The proximal cause of the abnormality is expressed as an abnormality in lens development, specifically in the lens fibers that fail to develop normally and form an opacity close to and sometimes adherent to the posterior capsule.

Maldevelopment of the lens fibers produces an opacity composed of disorganized, misshapen, and malformed lens fibers and vacuoles in the region of the posterior polar capsule. At times, this discoid opacity can actually adhere to the posterior capsule. The remainder of the lens can appear normal, and the pathology is limited to the specific area mentioned above. The genomic etiology has been localized to the chromosomes mentioned above. Its challenge as a surgical problem remains significant.

Presentation

Posterior polar cataract presents as a distinctive discoid lens opacity situated posteriorly, adjacent to the posterior capsule. Duke-Elder mentions stationary as well as progressive cataracts.[1]

Posterior polar cataract is easily seen and often clearly delineated. In its early stages, it can be seen interfering with the normal light reflex. Fully formed, it presents as a dense, circular plaque in the central posterior part of the lens. It can be surrounded by vacuoles and smaller areas of degenerated lens material. Often, the only benefit to the surgeon is that the defect is so clearly visible.

This entity is rare and can be seen to progress from its initial discovery. Surgical therapy is indicated once visual acuity is affected. Further, because of its mode of inheritance, ophthalmic examinations should be scheduled for family members.

Indications

Once visual acuity is diminished, amblyopia can develop and cataract removal is indicated. Since this type of lens opacity usually occurs directly in the visual axis, it does diminish vision more rapidly as compared to lens opacities that are located more peripherally. Moreover, since posterior polar cataracts can occur in a younger age group, the possibility of amblyopia must be considered. Lack of improved visual acuity after phacoemulsification is most common when the cataracts are unilateral, indicating amblyopia as the likely cause.[20] The case for early intervention is made on the basis that visual acuity impairment can lead to amblyopia.

The Lens Opacities Classification System (LOCS) that indicates the significance of the lens opacity is not clearly applicable here. A separate posterior polar cataract classification system has yet to be formally introduced.

The indication for posterior capsular cataract removal is often only a matter of time. Certainly, a visual acuity that is worse than 20/40 is a valid indication. In addition, de Jong et al suggest that elevated straylight may be an indication for cataract surgery independent of visual acuity. While visual acuity may be fairly well preserved, straylight can be very bothersome to patients, and straylight levels decrease after cataract surgery in patients with posterior polar cataracts.[21] While the patient can opt for surgery when the vision impairs daily activity or symptoms such a straylight become sufficiently bothersome, it is the surgeon's judgment that should determine the time of intervention.

Since posterior polar cataracts can present in the first several months of life, surgical intervention is indicated in the presence of a visually significant opacity. The suspicion of amblyopia predisposes to very early removal of the lens opacity. This is especially true if an unexplained decrease in visual acuity occurs without a concurrent change in the posterior polar cataract.

Relevant Anatomy

A posterior polar cataract consists of dysplastic lens fibers, which, in their migration posteriorly from the lens equator, exhibit progressive lens opacity with the formation of a characteristic discoid posterior polar plaquelike cataract.

Histology has shown that posterior polar cataracts consist of lens fibers that have developed abnormally. Further, the lens fibrils have degenerated and, in some cases, are directly attached to the posterior capsule. Often, the posterior polar opacified plaque is surrounded by a less distinct area of fibrillar degeneration as well as vacuoles filled with liquefied material.

The current literature points to a genomic cause of this entity. Several chromosomal abnormalities, the majority of which appear to exhibit an autosomal dominant inheritance pattern, are present in a familial distribution in posterior polar cataract cases. Because these cataracts appear to occur in familial groups, the focus has narrowed in on several specific chromosomes. These genomic aspects are also discussed in Etiology. Future work may shed light on the more detailed genomic defect of this subtype of lens opacity.

Contraindications

Contraindications include any concurrent medical condition that precludes cataract surgery. A complete ocular history and a family history must be obtained. After a full ophthalmic examination, any concurrent ocular pathology must be stabilized prior to surgical intervention. Ocular conditions, such as retinal detachment or glaucoma, as well as infections of any type must be treated. Once the patient is stabilized, surgery can then proceed.

The surgeon should use the same criteria to determine if surgery is appropriate in a posterior polar cataract case as that for a routine case.

 

Workup

Laboratory Studies

Apart from a complete blood count (including hemoglobin and hematocrit), no laboratory examinations have been shown to be necessary prior to posterior polar cataract surgery.

Imaging Studies

A chest radiograph may be obtained prior to surgery.

Anterior segment optical coherence tomography (AS-OCT) has been studied as a method to grade posterior polar cataracts and to identify eyes at high risk for poster capsule rupture. In a study by Chan et al involving 39 eyes, 18 of which were classified as grade 2 (< 50% clearance between the posterior opacity and the capsule) or grade 3 (absence of an intact posterior capsule), anterior segment OCT had a sensitivity of 87.5% and specificity of 62.1% in predicting intraoperative poster capsule rupture, showing that this imaging study could allow for better surgical planning and preoperative counseling.[22, 23] Pavan Kumar et al showed that preoperative AS-OCT had a sensitivity of 100% and specificity of 94.92% in detecting posterior capsule dehiscence, which further supports the use of AS-OCT to predict posterior capsule rupture during phacoemulsification in these patients.[24]

Other Tests

A-scan ultrasonography should be performed.

Although routinely done prior to almost all preoperative workups, keratometry readings should be performed to aid in intraocular lens (IOL) calculations.

Electrocardiography should be performed to rule out any associated disorders, which have been mentioned but often do not contraindicate posterior polar cataract surgery.

Diagnostic Procedures

The diagnosis of a posterior polar cataract is self-evident on slit-lamp examination and does not require special diagnostic procedures beyond a full ophthalmic examination. Slit-lamp examination and pupillary retroillumination allow a good evaluation of the visual significance of the opacity. The anterior vitreous should be examined carefully to ensure that it is free of opacity or capsular adherence.

Histologic Findings

A posterior polar cataract has been shown to present as an opacity in the subcapsular portion of the lens that consists of malformed, disorganized, and degenerated lens fibers. As these fibers migrate posteriorly from their origin at the equator, increased degenerative changes have been shown as they reach the posterior pole. This results in a dense discoid opacity that is often surrounded by an area of vacuoles and abnormal lens fibers. Often, these abnormal lens fibrils are connected to the underlying posterior capsule.

Staging

Posterior polar cataracts have not been staged, probably because of their rare occurrence.

At present, the Lens Opacities Classification System (LOCS) uses slit-lamp images to grade color and opalescence, as well as retroillumination images to grade cataracts and posterior subcapsular opacities. Cataract severity is graded on a decimal scale that reportedly shows good correlation between different observers. This system, however, does not specifically deal with posterior polar cataracts.

The literature is sparse on this aspect of posterior polar cataracts. The average practice encounters relatively few cases. Grading of posterior polar cataracts was reported by Forster and colleagues in 2006.[25] Out of 33 patients aged 1 week to 8 years with lens opacities, 3 patients were noted to have posterior polar cataracts. The grading was done subjectively and also objectively with the use of photographs. Grading used a scale of 0-10. Posterior polar cataracts graded a 6 indicated surgical removal.

A suggested concept would be to classify these opacities according to size and density. The size range would be 0.5-3 mm in increments of 0.5 mm. Density would be staged from 1+ to 4+ with increasing density as judged by the ability to visualize the posterior capsule.

Moreover, posterior polar cataracts can sometimes be associated with other lens opacities, which can be classified according to the LOCS.

Finally, the main hindrance in fully adopting a functional grading system for posterior polar cataracts appears to be the small sample sizes used. This is because the entity is rare. The author would be glad to receive case reports, which could be correlated into a meaningful classification algorithm.

 

Treatment

Medical Therapy

Therapy for posterior polar cataracts is primarily surgical, but safety is a consideration since this entity poses a special challenge. The timing of the intervention should be early enough to prevent the development of amblyopia.

A thorough pediatric and/or intermedical evaluation for associated systemic findings in all forms of congenital cataract, including posterior polar cataracts, is indicated. Kronenberg and colleagues reported on a rare syndrome with a rare neurocutaneous syndrome in which a chart review revealed significant eye abnormalities.[26] Duke-Elder cited a series of associated conditions, including ectodermal dysplasia, Rothmund disease, scleroderma, incontinentia pigmenti, congenital dyskeratosis, congenital ichthyosis, and congenital atrophy of the skin.[1]

Surgical Therapy

Posterior polar cataract surgery is challenging, even with the most advanced techniques available.[27, 28, 29, 30] The surgical pitfalls have been well documented in the ophthalmic literature. The importance of being aware of these surgical pitfalls and avoiding them cannot be overemphasized. It has been suggested that where hydrodelineation is difficult, prechopping of the anterior nucleus should be initially performed and any cracking of the nucleus should be limited so as to not involve the area near the posterior pole or the capsule.[31] As mentioned below, hydrodissection should be avoided because it can, in itself, cause the abnormally weakened posterior capsule to tear.

While the established hydrodelineation approach is detailed in Intraoperative Details, femtosecond laser-assisted cataract surgery is an emerging, promising tool in the treatment of posterior polar cataracts. The technique of femtodelineation is used to create multiple cylinders within the lens using the femtosecond layer. The creation of sharply demarcated layers allows the removal of one layer while the remaining layers act as mechanical barriers that protect the posterior capsule.[32] In addition, the sharp demarcation allows the last epinuclear layer to be easily stripped through the combined use of the phacoemulsification probe and bimanual irrigation and aspiration.[32] This technique has the distinct advantage of eliminating the need for hydrodissection. Vasadava et al have found that this technique reduces posterior capsule rupture rates and enhances safety.[32] Titiyal et al investigated this technique in 25 eyes with posterior polar cataract and nuclear sclerosis grades II to III, utilizing a combination of three cylinders (2, 4, and 6 mm) and three chops 6 mm in length for nuclear dissection.[33] With this technique, they had no cases with posterior capsule tears and suggest that this hybrid combination of cylinder and chop is both safe and effective in the management of posterior polar cataract, particularly in cases of higher-grade nuclear sclerosis.[33]

Preoperative Details

The preoperative clearance for posterior polar cataract surgery does not need to include more than that obtained prior to a routine cataract surgery.

A full and careful pediatric workup should be obtained with an emphasis on uncovering any associated systemic abnormalities. Appropriate subspecialty referrals should be obtained in the event of any significant findings.

Assuming the absence of any associated systemic or ocular disease, the preoperative preparation for posterior polar cataract surgery can be limited to a routine preoperative workup and clearance.

Intraoperative Details

Posterior polar cataract surgery is associated with an increased incidence of posterior capsular rupture. Undue stress on the capsule must be minimized. The main difficulty is the adherence of the abnormally formed lens fibers to the posterior capsule and its associated weakness. Moreover, the risk of posterior capsule rupture increases significantly when the capsular opacification is larger than 3 mm.[34] Once the surgeon is aware of these dangers, the technique can be altered to meet these challenges.

For this reason, special lower flow and aspiration settings should be used. This situation is described in the following case, which is used for illustrative purposes. Topical 4% Xylocaine anesthesia is instilled prior to inserting the lid speculum and positioning the eye to the operative microscope. The cataract is inspected and typically presents as a central posterior discoid mass. This can be surrounded by an area of degenerated fibrillar elements (see the image below).

The posterior polar cataract is seen as a dense di The posterior polar cataract is seen as a dense discoid opacity. The central fibrous mass consists of degenerated lens fibers surrounded by several small globular vacuoles containing what appears as a refractile substance as well as some lens degenerative fiber material.

A limbal side port incision can be used to instill 1% preservative-free Xylocaine solution into the anterior chamber.

Surgery begins in the usual manner with a clear corneal incision and capsulorrhexis. Care should be taken to minimize posterior pressure during all maneuvers.

Hydrodissection should be avoided because the fluid wave created may extend to the weak area of the posterior capsule and in itself produce a tear. Rotation of the cataract should also be avoided to prevent the application of any inadvertent torquing forces being transmitted to the posterior capsule.

Instead, the nucleus and the cortex should be outlined using hydrodelineation. The goal is to leave the posterior pole as undisturbed as possible by creating a hydrodissected plane separating the nucleus and the epinucleus. This should create a cushion of the cortex and the epinucleus, which should then cushion and protect the region of the central posterior capsule.

The anterior cortex and the nucleus are then removed using low aspiration and as little phacoemulsification as possible. Moreover, once the nucleus is removed, irrigation and aspiration, and especially phaco, should be directed obliquely as much as possible. Direct application of these forces to the posterior polar cataract should be avoided. These forces should be aimed obliquely so as not to cause inadvertent stress on the delicate posterior capsule. Indeed, it is sometimes possible to hydrodissect part of the discoid opacity free to the point where it can be safely removed (see the image below).

Removal of the nucleus and much of the cortex has Removal of the nucleus and much of the cortex has been completed with the aid of hydrodissection. Almost all of the posterior cortical opacity has also been aspirated. Only indirect irrigation and aspiration was used. Hydrodelineation has been avoided. There appears to be a ringlike remnant of the opacity that may have some adherence to the capsule.

Once this is achieved, the surgeon is still faced with the epinucleus and, more significantly, any residual posterior capsular adhesion. Dye has been introduced as an aid to ocular surgery.[35] As seen in the image below, the peripheral remnant of the opacity still remains. This presents the possibility of an area of capsular adherence, and care must still be exercised in aspirating this area.

Removal of the nucleus and much of the cortex has Removal of the nucleus and much of the cortex has been completed. Highly dilute fluorescein dye has been instilled to stain the remaining epinucleus but especially the remaining ringlike opacity. The capsule is still intact since the stain is limited to the anterior chamber. This aids in careful cortical aspiration without damage to the intact posterior capsule.

For this reason, highly diluted fluorescein has been instilled to delineate this remnant of the posterior polar cataract. Indeed, the appearance of this remnant is enhanced, and the 2- and 9-o'clock positions of the ring look especially suspicious (see the image above). Further, the integrity of the posterior capsule is verified because the dye has not spread into the region of the anterior vitreous.

Additional indirect irrigation can be used to further loosen and hydrate the remaining opacity using the silicone tip, which is an additional recommended safety feature. The remainder of the epinuclear cortex can then be aspirated, using vacuum levels as low as practical to avoid any additional stress (see the image below).

Aspiration of the subincisional cortex is shown. T Aspiration of the subincisional cortex is shown. The dye in the remaining ringlike edge of the cataract, at the 10-o'clock position, appears to show a small strand still adhering in the direction of the posterior capsule. A defect in the capsule has been avoided up to this point.

Finally, once aspiration has been completed, the posterior chamber intraocular lens can be implanted in the surgeon's usual fashion (see the image below). When using a viscoelastic, as during the entire case, care must be taken to avoid overpressurization of the anterior chamber, creating undue posterior force.

After careful cortical aspiration, a posterior cha After careful cortical aspiration, a posterior chamber lens is shown. The capsule has remained intact.

If the capsular opacity resists removal in the above maneuver, the surgeon may have to resort to a controlled posterior capsulorrhexis combined with a shallow anterior vitrectomy.

Postoperative Details

The patient should be examined the day after surgery, and the clarity of the cornea and the depth of the chamber should be assessed. Any complications should also be addressed.

A topical fourth-generation fluoroquinolone antibiotic as well as a nonsteroidal anti-inflammatory drug (NSAID) may be instilled.

A refraction is performed 6 weeks postoperatively; at which time, the eye should be well healed.

Follow-up

Once the eye has stabilized and no problems are present, the patient can be seen 3 months postoperatively and every 6 months thereafter.

Complications

The complications of wound leak, malpositioned intraocular lenses (IOLs), and endophthalmitis are well known and do occur in cases of posterior polar cataract surgery.

Moreover, since this entity occurs in a young age group, refractive errors tend to increase with age. The choice of IOL power should take this tendency into account. The necessity of lens exchange in these patients has not been documented but should be avoided as much as possible.

Outcome and Prognosis

The patient whose photographs are presented below had a clear cornea on postoperative day 1. Slit-lamp examination revealed the eye to be in good pseudophakic order. The patient was given a topical antibiotic and an NSAID, as described in Postoperative details.

The posterior polar cataract is seen as a dense di The posterior polar cataract is seen as a dense discoid opacity. The central fibrous mass consists of degenerated lens fibers surrounded by several small globular vacuoles containing what appears as a refractile substance as well as some lens degenerative fiber material.
Removal of the nucleus and much of the cortex has Removal of the nucleus and much of the cortex has been completed with the aid of hydrodissection. Almost all of the posterior cortical opacity has also been aspirated. Only indirect irrigation and aspiration was used. Hydrodelineation has been avoided. There appears to be a ringlike remnant of the opacity that may have some adherence to the capsule.
Removal of the nucleus and much of the cortex has Removal of the nucleus and much of the cortex has been completed. Highly dilute fluorescein dye has been instilled to stain the remaining epinucleus but especially the remaining ringlike opacity. The capsule is still intact since the stain is limited to the anterior chamber. This aids in careful cortical aspiration without damage to the intact posterior capsule.
Aspiration of the subincisional cortex is shown. T Aspiration of the subincisional cortex is shown. The dye in the remaining ringlike edge of the cataract, at the 10-o'clock position, appears to show a small strand still adhering in the direction of the posterior capsule. A defect in the capsule has been avoided up to this point.
After careful cortical aspiration, a posterior cha After careful cortical aspiration, a posterior chamber lens is shown. The capsule has remained intact.

During the seventh postoperative week, the posterior capsule opacified rather rapidly, and a YAG laser capsulotomy was performed. Emmetropia is difficult to achieve in these cases for several reasons. In this patient, the final refraction was +1.00 -0.50 X 87, and the patient preferred wearing a contact lens. When the patient reaches the third decade, an excimer laser correction can be performed if desired.

Without correction, the patient achieves a visual acuity of 20/40 and often prefers not to wear contacts or spectacles.

Future and Controversies

Posterior polar cataracts have been recognized as a distinctive subtype for many years. Recent advances in genomics have localized the chromosomal cause, and further work promises to elucidate the exact mechanism by which these cataracts form.

Regarding surgery, various approaches have been suggested to minimize complications, including a bimanual microincisional approach, the use of viscodissection, a pars plana approach, and posterior capsulorrhexis. These approaches all address the weakness of the posterior capsule with its tendency to rupture. Since this challenge will continue to persist, different surgical approaches will continue to be offered.

With this in mind, the technique presented herein is offered in the hope that it leads to fewer cases of capsular rupture.