Israel Medical Association Journal

Background: During combined phacovitrectomy, it is common practice to suture the main corneal incision to prevent intraoperative and postoperative wound leak. However, it may be possible to avoid suturing using a self-sealing corneal incision technique as in standard cataract surgery.

Objectives: To evaluate the clinical outcome, safety, and complications of combined phacovitrectomy without preventive suturing.

Methods: This retrospective case series study included consecutive patients who underwent combined phacovitrectomy between January 2018 and June 2019 for mixed indications. Surgeries were performed at a tertiary university hospital. All surgeries were performed by the same two retinal surgeons. Cataract surgery was performed first, followed by insertion of trocars and vitrectomy. Corneal sutures were not planned but were used at the discretion of the surgeon.

Results: The cohort included 106 eyes of 102 patients. Suturing of the main corneal incision was deemed necessary in five cases (5%) because of a main incision leak or anterior chamber shallowing during trocar insertion. No other complications related to the absence of prophylactic corneal sutures were encountered during surgery or follow-up.

Conclusions: Preventive corneal suturing may not be necessary in combined phacovitrectomy surgery and can be used in the few cases in which it is indicated during surgery.

Background: The cornea is one of the most densely innervated in the body. Pterygium surgery includes removal of the pterygium tissue from the cornea and conjunctiva followed by autologous conjunctival grafting.

Objectives: To examine the change in corneal and conjunctival sensation post-pterygium surgery.

Methods: This prospective study included patients with primary pterygium. We collected and analyzed demographic data, visual acuity (VA), refraction, quantified sensation, and corneal tomography. Comparison in sensation in the cornea, conjunctiva, and conjunctival autograft was recorded the day of surgery and at least 6 months postoperatively.

Results: Nine patients participated in the study. Mean follow-up time was 9 months (9 ± 3.3, 6–12.4). No complications were documented during or following surgery and no recurrences were found. Statistically significant increases in corneal sensation in the nasal corneal and in the nasal conjunctival areas were noted by the end of follow-up compared to before surgery (P = 0.05, paired samples t-test). There was a significant correlation between the increase in nasal corneal and conjunctival sensation with improved Schirmer testing outcomes and tear break-up time after surgery (P = 0.05, P = 0.01, Pearson correlation). There was a positive correlation between the changes in nasal corneal sensation after surgery and improved changes in VA (P = 0.02, Pearson correlation).

Conclusions: We found improvement in sensation 9 months after pterygium surgery, which may be due to reinnervation of the cornea and conjunctival autograft from the neighboring non-injured nerve fibers. Larger studies with confocal microscopy should be conducted for further analysis.

Background: Keratoconus is a non-inflammatory disease characterized by progressive corneal steepening, which leads to decreased visual acuity secondary to high irregular astigmatism.

Objectives: To compare the one-year outcomes of accelerated vs. standard collagen crosslinking (CXL) in the treatment of keratoconus.

Methods: A database search of patients who underwent CXL from 2009 to 2017 was conducted at the cornea clinic at Sheba Medical Center. Charts of 99 adult patients (124 eyes) were reviewed. All patients were diagnosed with keratoconus. Main outcome measures were change in keratometry, uncorrected visual acuity (UCVA), and best-corrected visual acuity (BCVA).

Results: We evaluated outcomes in two groups: CXL with standard (3 mW/cm² for 30 minutes) vs. the accelerated (9 mW/cm² for 10 minutes) protocol. There were no significant differences between the groups with regard to BCVA, UCVA, and mean spherical equivalent (P =0.83, 0.0519, 0.181, respectively). The corneal thickness in the center and thinnest location were higher in the accelerated group than the in the standard group (P = 0.126). Complication rates did not differ between the two groups.

Conclusions: Accelerated and standard CXL are both safe and effective techniques. Accelerated CXL confers the added benefit of being a faster procedure to both patients and surgeons.

Background: Eye trauma is an unfortunate and often preventable cause of vision loss. Confetti cannons are common causes of injury. Awareness of ocular hazards of confetti cannons remains low because of limited reports describing ophthalmic injuries following their use.

Objectives: To describe outcomes of ocular trauma caused by confetti cannons and to increase recognition of their ocular risks.

Methods: A retrospective analysis was conducted of eye injuries caused by confetti cannons presenting to a single medical center between 2016 and 2020. Data collected included age, gender, eye injured, ocular damage, visual outcome, and details of surgeries performed.

Results: Overall, six consecutive patients (2 males, mean age 19.5 ± 9.74 years) were identified and studied. In all patients only one eye was injured (3 right eyes) during a private celebration, most commonly (n=5) to a bystander while in the vicinity of a cannon operated by someone else. Most common eye injuries included corneal erosion (n=4), traumatic hyphema (n=4), and retinal edema (n=3). Mean initial logMAR visual acuity in the injured eye was 0.73 ± 0.18, improving to 0.25 ± 0.16 at the final visit (P = 0.125). Two patients underwent eye surgery due to their trauma: one to repair globe penetration and another to undergo intravitreal injection of tissue plasminogen activator and C3F8 for submacular hemorrhage, followed 8 months later by intravitreal bevacizumab injection for choroidal neovascularization.

Conclusions: Confetti cannons pose hazards that can cause severe ocular trauma resulting in permanent vision loss. Increasing awareness of device hazards is necessary to prevent eye injuries

Background: Warm compresses are widely touted as an effective treatment for ocular surface disorders. Black tea compresses are a common household remedy, although there is no evidence in the medical literature proving their effect and their use may lead to harmful side effects. 

Objectives: To describe a case in which the application of black tea to an eye with a corneal epithelial defect led to anterior stromal discoloration; evaluate the prevalence of hot tea compress use; and analyze, in vitro, the discoloring effect of tea compresses on a model of a porcine eye.

Methods: We assessed the prevalence of hot tea compresses in our community and explored the effect of warm tea compresses on the cornea when the corneal epithelium’s integrity is disrupted. An in vitro experiment in which warm compresses were applied to 18 fresh porcine eyes was performed. In half the eyes a corneal epithelial defect was created and in the other half the epithelium was intact. Both groups were divided into subgroups of three eyes each and treated experimentally with warm black tea compresses, pure water, or chamomile tea compresses. We also performed a study in patients with a history of tea compress use. 

Results: Brown discoloration of the anterior stroma appeared only in the porcine corneas that had an epithelial defect and were treated with black tea compresses. No other eyes from any group showed discoloration. Of the patients included in our survey, approximately 50% had applied some sort of tea ingredient as a solid compressor or as the hot liquid.

Conclusions: An intact corneal epithelium serves as an effective barrier against tea-stain discoloration. Only when this layer is disrupted does the damage occur. Therefore, direct application of black tea (Camellia sinensis) to a cornea with an epithelial defect should be avoided.

 

Background: Corneal haze is a significant complication of photorefractive keratectomy (PRK) and laser-assisted sub-epithelial keratectomy (LASEK).

Objectives: To evaluate the effect of ascorbic acid supplementation in addition to perioperative topical mitomycin-C for the prevention of haze after LASEK.

Methods: We performed a retrospective, non-randomized case series study of two groups of 48 consecutive patients (96 myopic eyes) who had LASEK surgery. The treatment group was given ascorbic acid (vitamin C) orally 500 mg twice daily from 1 week before to 2 weeks after surgery. The control group was not offered any additional treatment. Ascorbate supplementation was the only difference in the postoperative treatment protocol between the treatment and control groups. Haze was assessed on a scale from 0 to 4 at the 1 year visit.

Results: Overall, 33.3% and 37.5% of the patients in the treatment and control groups respectively developed corneal haze. The trend of increased haze severity in the control group did not reach statistical significance.

Conclusions: Our results showed that systemic ascorbate supplementation does not have an additional effect on the prevention of haze after LASEK compared to the effect of topical mitomycin-C alone.

Background: It is common practice to use topical antiseptic formulations prior to specific therapy in superficial infections and injuries, but not in corneal bacterial ulcers. There is accumulating evidence proving chlorhexidine gluconate 0.02%, an antiseptic agent, as an effective treatment for infectious keratitis.

Objectives: To investigate the safety and efficacy of chlorhexidine gluconate 0.02% as an adjunct therapy for corneal bacterial ulcers.

Methods: Twenty-six patients with corneal bacterial ulcers were treated with standard empirical antibiotic treatment. The study group was treated with chlorhexidine gluconate 0.02% while controls received placebo for one week. The patients were followed for at least 1 month.

Results: No allergic or toxic reactions were noted. Although a higher baseline severity of ulcers existed in the study group, no differences were found in final vision, scarring extent, or recovery duration.

Conclusions: Chlorhexidine gluconate 0.02% may improve the clinical course of corneal ulcers.
 

Background: Ocular hypotony is a common unexplained feature of myotonic dystrophy type 1. Spuriously low applanation tonometric readings can be caused by thin corneas, flat corneal curvature and corneal edema.

Objectives: To determine whether structure abnormalities of the cornea cause spuriously low readings in applanation tonometry.

Methods: We utilized a TMS-2N corneal topographer, a NonconRobo SP-6000 Specular microscope and a Corneo-Gage Plus 1A Pachymeter to examine seven patients with DM1[1] and eight healthy controls. Intraocular pressure, central corneal thickness, and endothelial cell density were measured, and simulated keratometry readings were made. Cornea guttata and irregularity of corneal topography patterns were also sought.

Results: The mean intraocular pressure was 9.86 ± 1.29 mmHg for all patients (intraocular operated and non‑operated eyes) and 12.88 ± 1.89 mmHg for the controls (P = 0.000021, two-tailed t-test). Central corneal thickness was 530.57 ± 35.30 micron for all patients and 535.00 ± 39.62 micron for the controls (P = 0.75, two-tailed t-test). Endothelial cell density was 3164 ± 761 cells/mm² for all patients and 3148 ± 395 cells/mm² for the controls (P = 0.94, two-tailed t-test). Simulated keratometry readings were similar in both groups when the operated eyes were excluded. Cornea guttata and irregularity of corneal topography patterns were also noted in the study group.

Conclusions: Corneal thickness, corneal curvature and corneal hydration were within normal limits and thus were not the cause for the low applanation tonometry reading in DM1. The presence of cornea guttata and irregularity of corneal topography patterns in DM1 warrants further investigation. 

Orbital dog bites, although uncommon, occur mostly in children and are reported to be associated with severe ocular adnexal injury without globe involvement.

Background: Corneal erosions, a common and very painful ailment, are traditionally treated with pressure patches and antibiotic ointment but the healing is slow.

Objectives: To report our experience with the use of therapeutic contact lenses for the primary treatment of traumatic corneal erosions.

Methods: During the last 5 years in a single community clinic 65 consecutive patients with traumatic corneal erosions were treated with a corneal contact lens and antibiotic drops as a routine measure. The charts were reviewed for outcome, side effects and complications.

Results: Healing of the corneal erosions occurred within 1 to 3 days in all patients, with minimal or no pain. No corneal infection occurred. One patient had a recurrence that was successfully treated by lens placement.

Conclusions: The therapeutic contact lens with antibiotic drops is a safe and effective method to treat traumatic corneal erosions, and patients can immediately resume their regular activities.

The chemical warfare agent sulfur mustard affects primarily the eyes, skin and respiratory tract. Of these, ocular injury is the most immediate and distressing. Learning to recognize ocular injury enables the treating physician to provide early and suitable treatment, which will reduce complications and allow the victim a rapid recovery.

Background: Most corneal damage induced by contact lenses is due to interference with corneal oxygenation.

Objective: To investigate the effect on the rabbit cornea of a rigid gas-permeable contact lens with a newly designed periphery.

Method: We fitted New Zealand white rabbits (n=12) with RGP[1] contact lenses that were identical in all respects except for the design of the periphery. In each animal, one contact lens had an innovative periphery consisting of a microscopic diffractive relief lathed on the back surface; the other contact lens was of a conventional design. The lenses were worn continuously for 7 days. During this experimental period and for 1 additional week we assessed the corneal damage by daily testing lactic dehydrogenase activity in the tears.

Results: On the last day of the experimental week and the first 3 days of the healing period, mean tear LDH[2] activity was significantly lower in the eyes with the new contact lens design than in eyes with the conventional lenses.

Conclusions: The novel periphery design reduces corneal damage resulting from contact lens wear, as reflected by LDH levels in the tears. The new design probably facilitates the flow and exchange of tears under the contact lens, resulting in improved metabolism of the cornea. These findings may also prove applicable to soft contact lenses.