Reversible cataract after exposure to distilled water: a case report

Transient vacuolar changes of the crystalline lens in patients using a dispersive ophthalmic viscosurgical device

AIM

To report the clinical prognosis and pathological findings of accidental lens vacuolar changes in eyes with intraoperative exposure to a dispersive ophthalmic viscosurgical device (OVD).

METHODS

Two patients who developed transient lens vacuolar changes during uneventful persistent pupillary membrane (PPM) removal surgery were presented and followed up. This event was speculated to be associated with an intraoperative dispersive OVD DisCoVisc (hyaluronic acid 1.6%-chondroitin sulfate 4.0%) exposure. Then, to provide the pathological basis for our speculation, another four cataract patients were randomly exposed to different OVDs, and their anterior lens capsules were investigated with transmission electron microscopy (TEM).

RESULTS

After months, the subcapsular vacuoles in both PPM cases were gradually disappeared without visual deterioration. For the cataract patients, similar lens changes were observed intraoperatively in those exposed to a dispersive DisCoVisc but not a cohesive OVD IVIZ (sodium hyaluronate gel 1.0%). In addition, marked ultrastructural changes, including chromatin condensation, extensive cytoplasmic vacuoles, and obvious intercellular space between lens epithelial cells in the anterior lens capsules of all eyes exposed to DisCoVisc, were observed by TEM.

CONCLUSION

The lens vacuolar changes may be associated with a dispersive OVD exposure. Therefore, it is not preferable to use dispersive OVDs in patients with transparent lenses or without the intention of lens extraction. In addition, close follow-ups instead of immediate lens extraction are recommended for the occurrence of similar lens lesions.

Spontaneous resolution of a unilateral cataract in an adult: A case report

RATIONALE

Cataracts are a disease that is usually caused by aging and involve the irreversible degeneration of the lens material. On the other hand, transient cataracts have also been reported, mainly due to systemic hyperglycemia, which often occurs bilaterally. However, reports of the spontaneous regression of unilaterally occurring cataracts in patients with normal blood glucose levels are rare. Here, we report a rare case of spontaneous regression of unilateral posterior subcapsular cataracts in an adult with normal blood glucose levels.

PATIENT CONCERNS

A 42-year-old woman presented with distorted vision in her right eye. The patient was taking medication for diabetes, and her blood sugar level was well-controlled.

DIAGNOSIS

Upon examination, her uncorrected visual acuity and best-corrected visual acuity were 20/70 in her right eye. Slit lamp microscopy revealed fine, feathery, and streak-like posterior subcapsular opacities. Color fundus photography revealed a star-shaped shadow due to the cataract, and no diabetic retinopathy was observed. Her two hour postprandial glucose level was 115 mg/dL. The patient was diagnosed with posterior subcapsular cataracts, and cataract surgery was planned. The patient was scheduled to visit the clinic again after seven days.

INTERVENTIONS

Close observation for one week without any intervention.

OUTCOMES

After one week, most of the posterior subcapsular opacities disappeared, and the uncorrected visual acuity and best-corrected visual acuity in the right eye improved to 20/40 and 20/30, respectively.

LESSONS

This case report demonstrates that unilateral posterior subcapsular cataracts may spontaneously regress in patients with normal blood glucose levels. Therefore, it is important to check whether cataracts improve spontaneously through short-term close follow-up before planning cataract surgery to avoid unnecessary surgery.

Cataract Surgery by Intraoperative Surface Irrigation with 0.25% Povidone-Iodine

Postoperative endophthalmitis after cataract surgery is typically caused by the patient's own conjunctival normal bacterial flora. A three-step approach is recommended to prevent endophthalmitis: (1) "border control" to prevent microorganisms from entering the eye by disinfecting the ocular surface is the most important measure; (2) bacteria that have gained access into the anterior chamber are reduced by irrigation; (3) bacteria remaining in the anterior chamber and vitreous at the end of surgery are controlled by antibacterial drugs. We have devised a method, "the Shimada technique", for irrigating the ocular surface with povidone-iodine, a disinfectant with potent microbicidal effect and established effective and safe concentrations for eye tissues. Povidone-iodine exhibits a bactericidal effect for a wide concentration range of 0.005-10%, but 0.1% povidone-iodine has the highest activity and requires the shortest time of only 15 s to achieve microbicidal effect. When used to irrigate the ocular surface every 20-30 s during cataract surgery, 0.25% povidone-iodine is conceivably diluted to around 0.1%. Irrigation with 0.25% povidone-iodine during cataract surgery significantly reduced bacteria contamination rate in the anterior chamber compared with saline (p = 0.0017) without causing corneal endothelial damage.

Spontaneous Resolution of a Rapidly Formed Dense Cataract Following Nd: YAG Laser Peripheral Iridotomy in a Case of Pigmentary Glaucoma

A 54-year-old man was referred for a senior opinion. His vision had acutely dropped in his right eye from 6/6 to hand movements following Nd:YAG laser peripheral iridotomy for treatment of pigmentary glaucoma. A dense rosette posterior subcapsular cataract had formed in his right eye rapidly after surgery. Within 4 weeks the cataract resolved spontaneously and his vision returned to 6/6. It is hypothesized that a dual mechanism caused the rapidly formed cataract. Shockwaves stemming from Nd:YAG laser resulted in a reversible misalignment of the lenticular fibers, and localized direct damage to capsule caused osmotic imbalance and fluid collection between lamellae. Restoration of the osmotic balance, repair, and formation of lens fibers and clearing of vacuoles led to the resolution of the cataract. The proximity of the concave iris to the lens equator in pigmentary glaucoma was a predisposing factor. This highlights the importance of exercising great caution in using laser peripheral iridotomy in cases of pigmentary glaucoma, particularly if a higher laser power is used and considering initial conservative management of this complication.