Senile Cataract (Age-Related Cataract) Treatment & Management

No time-tested, FDA-approved, or clinically proven medical treatment exists to delay, prevent, or reverse the development of senile cataracts.

Aldose reductase inhibitors, which are believed to inhibit the conversion of glucose to sorbitol, have shown promising results in preventing sugar cataracts in animals. Other anticataract medications being investigated include sorbitol-lowering agents, aspirin, glutathione-raising agents, and antioxidant vitamins C and E.

The definitive management for senile cataract is lens extraction. Over the years, various surgical techniques have evolved from the ancient method of couching to the present-day technique of modern phacoemulsification. Phacoemulsification offers the advantage of a smaller incision size at the time of cataract surgery. ^[23] Historically parallel to the development of phacoemulsification is the evolution of advanced IOL design, which offers a wide selection of target implantation locations, materials, chromophores, premium features, and manner of implantation. Differentiated by the integrity of the posterior lens capsule, the 2 main types of lens surgery are the intracapsular cataract extraction (ICCE) and the extracapsular cataract extraction (ECCE). Below is a general description of the 3 commonly used surgical procedures in cataract extraction, namely ICCE, standard ECCE, and phacoemulsification. Referencing literature dedicated specifically to cataract surgeries for a more in-depth discussion of the topic, particularly with regard to technique and procedure, is also recommended.

Results from a large database study by Lundström et al indicate that poor visual outcome following surgery is most strongly determined by the following factors ^{[24, 25]} :

• Short-term postoperative complications

• Ocular comorbidity

• Surgical complications

• Complex surgery

Data (some self-reported) for the study were drawn from the European Registry of Quality Outcomes for Cataract and Refractive Surgery, which contained information on 368,256 cataract extractions. According to the investigators, although cataract surgery yielded excellent visual outcomes for more than 60% of patients in the study, vision was unchanged in 5.7% of them, while 1.7% of patients experienced a decrease in corrected distance visual acuity (CDVA). ^{[24, 25]}

Intracapsular cataract extraction

Prior to the onset of more modern microsurgical instruments and better IOLs, ICCE was the preferred method for cataract removal. It involves extraction of the entire lens, including the posterior capsule and mechanical or enzymatic lysis of the zonular support structures. In performing this technique, there is no need to worry about subsequent development and management of capsular opacity. The technique can be performed with less sophisticated equipment and in areas where operating microscopes and irrigating systems are not available.

However, a number of disadvantages and postoperative complications accompany ICCE. The larger limbal incision, often 160°-180°, is associated with the following risks: delayed healing, delayed visual rehabilitation, significant against-the-rule astigmatism, iris incarceration, postoperative wound leaks, and vitreous incarceration. Corneal edema is a common postoperative complication.

Furthermore, endothelial cell loss is greater in ICCE than in ECCE. The same is true about the incidence of postoperative cystoid macular edema (CME) and retinal detachment. The broken integrity of the vitreous face can lead to postoperative complications, even after a seemingly uneventful operation. Finally, because the posterior capsule is not intact, the IOL to be implanted must be placed in the anterior chamber, sutured to the iris, or surgically fixated in the posterior chamber. Both techniques are more difficult to perform than simply placing an IOL in the capsular bag and are associated with postoperative complications, the most notorious of which is pseudophakic bullous keratopathy (PBK).

Although the myriad postoperative complications has led to the decline in popularity and use of ICCE, it still can be used when zonular integrity is too severely impaired to allow successful lens removal and IOL implantation with an ECCE, particularly carefully selected posttraumatic and hypermature cataracts. Furthermore, ICCE can be performed in remote areas where more sophisticated equipment is not available.

ICCE is contraindicated in children and young adults with cataracts and any case with traumatic capsular rupture where intact removal of the lens capsule unit may prove difficult or incomplete. Relative contraindications include high myopia, Marfan syndrome, morgagnian cataracts, and vitreous presenting in the anterior chamber. Many of these patients may benefit from a pars plana lensectomy by a vitreoretinal surgeon prior to implantation of the appropriate IOL type.

Extracapsular cataract extraction

In contrast to ICCE, ECCE involves the removal of the lens nucleus through an opening in the anterior capsule with retention of posterior capsular integrity. ECCE possesses a number of advantages over ICCE, most of which are related to an intact posterior capsule, as follows:

• A smaller incision is required in ECCE, and, as such, less trauma to the corneal endothelium is expected. Only the diameter of the nucleus must be accommodated by the opening rather than the diameter of the entire lens within its capsule.
• Short- and long-term complications of vitreous adherence to the cornea, iris, and incision are minimized or eliminated.
• A better anatomical placement of the IOL is achieved with an intact posterior capsule.
• An intact posterior capsule also (1) reduces the iris and vitreous mobility that occurs with saccadic movements (eg, endophthalmodonesis); (2) provides a barrier restricting the exchange of some molecules between the aqueous and the vitreous; (3) reduces the incidence of CME, retinal detachment, and corneal edema; and (4) reduces movement of the IOL upon eye movements and eye rubbing (pseudophakodonesis).
• Conversely, an intact capsule prevents bacteria and other microorganisms inadvertently introduced into the anterior chamber during surgery from gaining access to the posterior vitreous cavity and causing endophthalmitis.
• Secondary IOL implantation, filtration surgery, corneal transplantation, and wound repairs are performed more easily with a higher degree of safety with an intact posterior capsule.

The main requirements for a successful ECCE and endocapsular IOL implantation are zonular integrity and an intact posterior capsule. As such, when zonular support is insufficient or appears suspect to allow a safe removal of the cataract via ECCE, ICCE or pars plana lensectomy should be considered.

Phacoemulsification

Standard ECCE and phacoemulsification are similar in that extraction of the lens nucleus is performed through an opening in the anterior capsule or anterior capsulotomy. Both techniques also require mechanisms to irrigate and aspirate fluid and cortical material during surgery. Finally, both procedures place the IOL within the capsular bag, which is far more anatomically correct than the anteriorly placed IOL.

Needless to say, significant differences exist between the 2 techniques. Removal of the lens nucleus in ECCE can be performed manually in standard ECCE or with an ultrasonically driven needle to fragment the nucleus of the cataract and then to aspirate the lens substrate through a needle port in a process termed phacoemulsification.

The more modern of the 2 techniques, phacoemulsification offers the advantage of using smaller incisions, minimizing complications arising from improper wound closure, and affording more rapid wound healing and faster visual rehabilitation. Furthermore, it uses a relatively closed system during both phacoemulsification and aspiration with better control of intraocular pressure during surgery, providing safeguards against positive vitreous pressure and choroidal hemorrhage. A closed system also minimizes fluid turbulence within the anterior chamber, reducing endothelial and trabecular meshwork trauma. However, more sophisticated and expensive machines, disposables, and instruments are required to perform phacoemulsification.

An advancement in cataract surgery techniques is the Femtosecond Laser Assisted Cataract Surgery (FLACS), which employs femtosecond laser in the various stages of phacoemulsification such as wound construction, anterior capsulotomy, and nuclear fragmentation.  The laser creates cleavage planes through photodisruption, resulting in greater precision and repeatability in the mentioned steps compared with the manual technique.

Ultimately, the choice of which of the 2 procedures to use in cataract extraction depends on the patient, the type of cataract, the availability of the proper instruments, and the degree to which the surgeon is comfortable and proficient in performing standard ECCE or phacoemulsification. The vast majority of modern cataract surgeons perform and prefer phacoemulsification.

The surgeon should also consider whether to use topical or regional anesthesia during the procedure. A study by Zhao et al examined the clinical outcomes of topical anesthesia and regional anesthesia including retrobulbar anesthesia and peribulbar anesthesia in phacoemulsification. The authors found that regional anesthesia provides better perioperative pain control, but that surgical outcomes were the same for both. ^[26]

Other Considerations

Although single-eye cataract surgery improves vision, including the second eye may yield greater rewards, according to a prospective, population-based study by Lee et al. The investigators studied 1739 participants aged 65-84 years at enrollment, 90 of whom following enrollment had unilateral cataract surgery, and 29 of whom had bilateral surgery. In the 1620 patients who did not undergo surgery, bilateral baseline best-corrected visual acuity logarithm of the minimum angle of resolution (BCVA of logMAR) was no greater than 0.3 (at least 20/40). ^{[27, 28]}

BCVA of logMAR improved by 0.04 in the unilateral group and 0.13 in the bilateral group, while reading speed increased by 12 words per minute in the unilateral group and 31 words per minute in the bilateral group. Moreover, the Activities of Daily Vision Scale scores (measuring vision at a distance, close-up, glare, and day and night driving) showed a 5-point relative improvement in the bilateral group, while the unilateral group actually showed a 5-point relative decrease.

An increased risk for intraoperative floppy iris syndrome (IFIS) was observed during cataract surgery in patients with benign prostatic hypertrophy (BPH) who were taking a nonselective alpha1-antagonist. Alfuzosin and tamsulosin, 2 drugs commonly used to treat BPH, are both linked to permanent changes in the iris and associated with an increased risk of IFIS. A prospective, masked, cross-sectional multicenter study by Chang et al determined that patients taking systemic alfuzosin for BPH were less likely to experience moderate or severe IFIS during cataract surgery than patients taking tamsulosin. ^{[29, 30]}

Of the 226 eyes studied, 70 were in patients receiving systemic tamsulosin, 43 in patients receiving systemic alfuzosin, and 113 in patients with no history of systemic alpha1-antagonist therapy. ^[30] The incidence of IFIS was 34.3% in the tamsulosin group, 16.3% in the alfuzosin group, and 4.4% in the control group. Severe IFIS was statistically more likely with tamsulosin than with alfuzosin (P = 0.036). Thus, patients with symptomatic BPH and cataracts requiring a uroselective alpha1-antagonist may consider trying alfuzosin first.

Bell et al reviewed exposure to alpha-adrenergic blockers frequently prescribed to treat benign prostatic hypertrophy (BPH) and their association with serious intra-operative adverse effects during cataract surgery. ^[31] The study included more than 96,000 older men who had cataract surgery over a 5-year period (3.7% had recent exposure to tamsulosin and 7.7% had recent exposure to other alpha blockers). Exposure to tamsulosin within 14 days of cataract surgery was significantly associated with serious postoperative ophthalmic adverse events (7.5% vs 2.7%; adjusted odds ratio [OR], 2.33; 95% confidence interval [CI], 1.22-4.43), specifically intraoperative floppy iris syndrome and its complications (ie, retinal detachment, lost lens or fragments, uveitis, endophthalmitis).A study by Baker et al found that 23-gauge pars plana vitrectomy is a possible surgical management approach in select cases of retained lens fragments. While 12 patients were successfully treated by this initial intervention, 8 required sclerotomy enlargement to a 20-gauge access. ^[32]

An association between cataract surgery and late age-related macular degeneration, independent of additional risk factors, has been shown in some studies. ^[33] Most surgeons do not believe that cataract extraction accelerates the onset of age-related macular degeneration. UV protection with sunglasses and hats is always recommended following cataract extraction.

Multifocal IOLs after cataract extraction are more effective at improving near vision than monofocal IOLS are, but whether this improvement outweighs the potential adverse effects of multifocal lenses varies between patients. ^[34] Careful patient selection to recommend a multifocal IOL only to patients with a pristine macula and ocular surface can be very rewarding for both the clinician and patient.

In 2008, the US Food and Drug Administration (FDA) approved the Alcon line of acrylic toric IOLs. In 2013, the FDA approved Abbott's Tecnis Toric 1-piece IOL to treat preexisting astigmatism in patients with cataract. ^[35] Toric IOLs are used to manage corneal astigmatism in patients who have undergone cataract surgery and whose natural lenses have been removed. Unlike other devices on the market, this 1-piece IOL can correct loss of focus of 1 diopter or greater. Clinical data show that the device offers exceptional rotational stability while improving visual results and improving distance and night vision.

In early 2014, the FDA approved a synthetic polyethylene glycol hydrogel sealant (ReSure Sealant, Ocular Therapeutix, Inc) for use in cataract surgery with IOL placement. ^[36] The sealant is indicated for prevention of postoperative fluid egress from incisions with a demonstrated wound leak after cataract surgery. Approval was based on a prospective, randomized, controlled multicenter study of 471 patients in which the sealant was more effective than a single suture in preventing incision leakage in the 7 days after surgery.

Prior to surgery, a thorough preoperative evaluation must be conducted, which would also include a thorough explanation of the procedure to be performed and its accompanying risks.

Not all senile cataracts require removal at the time of diagnosis. If vision, performance of daily tasks, and quality of life are not impaired significantly or if the patient is not prepared medically, psychologically, and financially for surgery, periodic consultations are encouraged to assess progression of the cataract. The procedure is, by definition, almost always elective. Very rarely, lens-induced glaucoma or uveitis warrants urgent or emergent cataract surgery.

Postoperatively, regular follow-up visits are necessary to monitor visual rehabilitation, as well as to detect and address any immediate and late complications arising from the surgery.

In relation to the surgery, no established dietary restrictions exist that would affect the course of the operation when a small corneal incision technique is planned. Larger scleral incisions, MIGS, simultaneous pars plana vitrectomy, or a planned retrobulbar anesthetic may dictate limitation of any dietary supplement (eg, fish oil) that may prolong bleeding times 2 weeks prior to surgery.

After surgery, the patient is dissuaded from performing activities that would increase the intraocular pressure, especially after undergoing ICCE or standard ECCE. These activities include lifting heavy loads, chronic vigorous coughing, and straining. Similarly, trauma and exposure to toxic fumes or particular matter should specifically be avoided.

Major intraoperative complications encountered during cataract surgery include the following:

• Shallow or flat anterior chamber

• Capsular rupture

• Corneal edema

• Suprachoroidal hemorrhage or effusion

• Expulsive choroidal hemorrhage

• Retained lens material

• Vitreous disruption and incarceration into wound

• Iridodialysis

• Retinal light toxicity

Major immediate postoperative complications encountered during cataract surgery often seen within a few days or weeks after the operation include the following:

• Flat or shallow anterior chamber due to wound leak

• Choroidal detachment

• Pupillary block

• Ciliary block

• Suprachoroidal hemorrhage

• Stromal and epithelial edema

• Hypotony

• Brown-McLean syndrome (peripheral corneal edema with a clear central cornea most frequently seen following ICCE)

• Vitreocorneal adherence and persistent corneal edema

• Delayed choroidal hemorrhage

• Hyphema

• Elevated intraocular pressure (often due to retained viscoelastic)

• Cystoid macular edema - Studies have shown that diclofenac was more effective than topical steroids in preventing CME. ^[37]

• Retinal detachment - Significant risk factors include axial length greater than 25 mm, age younger than 65 years, and intraoperative complications. ^[38]

• Acute endophthalmitis

• Toxic anterior segment syndrome (TASS), a noninfectious acute inflammatory reaction to particulate, chemical, or toxic matter placed in the anterior chamber during surgery - Most commonly implicated are sterile denatured lens proteins retained by surgical instruments, epinephrine solutions that contain bisulfites, and powder from surgical gloves; many mini-epidemics of TASS reveal no obvious proven cause despite intensive investigation

• Uveitis-glaucoma-hyphema (UGH) syndrome

Major late postoperative complications seen weeks or months after cataract surgery include the following:

• Suture-induced astigmatism

• Pupillary capture, decentration, or iris atrophy

• Decentration and dislocation of the IOL

• Corneal edema and pseudophakic bullous keratopathy

• Chronic uveitis

• Chronic endophthalmitis

• Wrong power of IOL used

At any postoperative stage, the risk of uveitis, noninfectious endophthalmitis, and infectious endophthalmitis exists. Noninfectious endophthalmitis is believed to be a multifactorial process or an idiosyncratically variable response to a common factor, similar to a hypersensitivity reaction. Treatment may range from the use of topical, transseptal, or oral steroids to the rare explantation of the intraocular lens.

Although of low incidence, infectious endophthalmitis may lead to severe vision loss and blindness. ^[39]  Staphylococcus epidermidis is the most commonly isolated organism in acute cases, and rupture of the posterior capsule is one of the most common risk factors. ^[39]  Of late, a significant increase in the incidence of gram-positive bacteria in bacterial isolates from postoperative eyes suspected of having endophthalmitis has been observed. Furthermore, a significant increase in resistance to ciprofloxacin and other fluoroquinolones has occurred. Seemingly, the spectrum of bacteria causing postcataract endophthalmitis is changing, partly perhaps because of an increased resistance to mainstay antibiotics in the prevention of endophthalmitis. Delayed-onset infectious endophthalmitis is most commonly caused by Propionibacterium acnes.

Age is believed to be the most significant risk factor for senile cataract and, as such, it is essentially inevitable that some degree of lens opacity develops as one becomes older. No study has established firmly whether avoidance of some of the risk factors for senile cataract (eg, UV exposure, hypercholesterolemia, tobacco use, diabetes mellitus) will lessen the chance of developing a senile cataract.

On the first postoperative day, visual acuity should be consistent with the refractive state of the eye, the clarity of the cornea and media, and the visual potential of the retina and optic nerve. Mild edema of the eyelid may be evident, as well as some conjunctival injection. The cornea is normally clear with minimal edema and striae. The anterior chamber should be deep with mild cellular and flare reaction. It is important to check whether the posterior capsule is intact and whether the IOL is positioned properly. The red reflex must be strong and clear and the intraocular pressures should be within normal limits. Transient intraocular pressure elevations may be observed and are often attributed to retained viscoelastic material.

Significant improvement of these initial findings is to be expected in subsequent postoperative evaluation as the ocular inflammation subsides typically within 2 weeks. Topical steroids and antibiotics are tapered accordingly. Refraction is believed to be stable at the sixth to eighth postoperative week, at which time corrective lenses can be prescribed. Significant postoperative astigmatism following ECCE or ICCE can be addressed by suture removal after the sixth postoperative week as guided by keratometry, refraction, or corneal topography.

In a prospective, randomized, double-masked trial involving 59 patients undergoing cataract surgery, use of a tapered-release dexamethasone punctum plug after surgery, compared with the use of a placebo plug (Dextenza, Ocular Therapeutix), resulted in fewer cells in the anterior chamber (ie, less evidence of ocular inflammation), lower use of additional anti-inflammatory medications, and less light sensitivity. ^[40]

The mean pain score in the dexamethasone group on the first day following surgery was three times below that in the placebo group (0.6 vs 2.0), while the ocular pain score on day 14 was 11 times lower than that in the placebo patients. No long-term, plug-associated intraocular pressure spikes or adverse events were observed.

Most cataract surgeries are performed on an outpatient basis, especially with the widespread adoption of phacoemulsification performed under topical anesthesia. Often, patients are discharged from the clinic as soon as they have recovered from the emotional stress of the procedure. Patients are sent home on topical steroids, NSAIDs, and antibiotics either separately or in combination. An optional eye shield is placed on the newly operated eye and removed a few hours later.

During the postoperative period, the patient is prescribed a topical steroid such as 1% prednisolone acetate, which is applied every hour for the first day, then tapered depending on the inflammatory state of the eye. Studies have shown that topical ketorolac tromethamine provides adequate postoperative control of intraocular inflammation without the risk of increased intraocular pressure, which may be associated with steroid use. A broad-spectrum topical antibiotic also is given 4-6 times a day for 1-2 weeks.