Keratoconus and Fitness to Fly

BACKGROUND: Of the body senses, vision is the most important for safe flight. Keratoconus causes progressive blurring and distortion of vision, which threatens the career of a civilian or military aviator. The goal of this retrospective study was to describe a series of keratoconus cases in a pilot population and to discuss decisions about their flight waivers.METHODS: To assess the impact of keratoconus on flying careers, we reviewed the records of all aviators with keratoconus examined in an Aeromedical Center over the past 5 yr.RESULTS: The files of 19 pilots [13 line pilots and 6 military pilots (3 fighter pilots)] were collected and analyzed. Of the 19 patients, 2 did not obtain flight fitness waivers. Among the 17 who received waivers, correction for defective distant vision (glasses or contact lenses) was imposed on 5 aviators.DISCUSSION: Keratoconus is a medical condition with aeromedical significance that should be detected by aeromedical examiners. A flight license can only be considered if the disease is stable and with satisfactory visual quality. Double pass aberrometry may be helpful to determine flight fitness. This study shows that keratoconus is not always a disability for aviators. Most of them are able to continue their flying careers safely. However, it must be analyzed on a case-by-case basis.Delbarre M, Crepy P, Froussart-Maille F. Keratoconus and fitness to fly. Aerosp Med Hum Perform. 2022; 93(12):840-845.

Sutureless Lyophilized Amniotic Membrane Grafting for Corneal Epithelial Defects

OBJECTIVES

To report the tolerability, safety, and efficacy of the lyophilized amniotic membrane (AM) Visio-AMTRIX placed under a bandage contact lens (BCL) in treating persistent epithelial defects (PEDs).

METHODS

This retrospective study included consecutive patients with PEDs treated with a lyophilized AM placed under the BCL. Patients with PEDs who did not respond to medical treatment were included. Patients with a follow-up time less than 3 months were excluded.

RESULTS

Eleven eyes of 11 patients (mean age, 61.6±15.9 years) were included. Time from PED presentation to AM transplantation (AMT) was 27.7±4.9 days, with the mean PED area of 13.2±11.3 mm2. Complete resolution was achieved in 8 of 11 eyes after a single AM graft. The epithelial defect persisted after the first AMT in three eyes (27.3%), and a second graft was necessary to achieve complete healing. The corneal epithelial defect healed in an average of 11.0±4.4 days after grafting. After PED resolution, the best-corrected visual acuity significantly improved from 0.66±0.30 logMAR (20/91 Snellen) to 0.58±0.24 logMAR (20/77 Snellen) (P=0.036) compared with baseline. The AM resorbed within 2 weeks in all cases. No complication or recurrence was observed.

CONCLUSIONS

A sutureless lyophilized AM under the BCL can resolve PEDs with a significant improvement in vision.

Incidence and characteristics of rhegmatogenous retinal detachment during coronavirus-19 pandemic: A French study

Purpose

To assess the impact of the Covid-19 pandemic and subsequent lockdown on the number and clinical characteristics of patients with retinal detachment (RD) in a French public university eye hospital.

Methods

Single-center, retrospective non-interventional study. Patients consulting at the emergency room (ER) of Quinze-Vingts Hospital (France) for rhegmatogenous RD before and after instauration of the lockdown were reviewed. We compared the characteristics of patients with RD between the containment period (March17th - April27th,2020) and the period preceding the lockdown (February18th - March16th,2020). We compared the number of RD surgeries performed between the first month of lockdown (March17th - April19th,2020) and the corresponding period of 2019. Number of cases, delay between diagnosis and surgery, visual acuity was measured.

Results

During the first month of lockdown, 59 RDs were operated on, compared to 107 in the corresponding period in 2019 (-44,8%). Mean time from first symptoms to surgery was significantly higher during the lockdown 12.7 (11.3) days vs 7.6 (7.8) days (p = 0.031) before. During the lockdown, the mean BCVA was lower albeit the difference did not reach statistical significance (1.16 (0.9) during pre-containment vs 1.5 (0.9) during containment; p = 0.09). Reasonsfor delayed consultation were: fear of Covid-19 (31%; p = 0.0001), absence of referral doctor (31%; p = 0.003) and difficulties in getting to public transport (10.3%;p = 0.859).

Conclusion

Despite maintaining accessto emergency eye care facilitiesin our hospital, the lockdown affected visual health. Should the lockdown be reinstated, we postulate that a better information about eye care access for non-Covid emergencies may attenuate its effect on visual health.

Eyelid Chemical Burns: A Multidisciplinary And Challenging Approach

During second- and third-degree eyelid sulfuric acid burns, many surgeons prefer to wait until primary wound separation occurs before grafting. However, this approach may miss the chance to recover the eyelids and can cause ectropion, resulting in delayed eyeball healing with exposure keratitis. We propose that early eyelid release and grafting makes a significant difference in long-term outcomes and improves eyeball healing. Here, we present the case of a woman who presented second- and third-degree burns of the eyelids secondary to physical domestic assault with acid, who had an early surgical management with a full-thickness skin graft. Ten days after surgery, we found that the graft had survived totally, and the donor site of the right arm had already healed. Eyelids were successfully grafted and the functions of both eyelids were well recovered, allowing complete cover of the eyeball. Two months after surgery, functional and cosmetic results were satisfying, with no postoperative lagophthalmos or difficulties with exposure-related problems. Case reports of eyelid chemical burns are very few. No specific and codified management of eyelid chemical burns was found in the literature search. This case report demonstrated that a multidisciplinary approach led by both ophthalmologists and plastic surgeons must be decided early (<6h) in order to achieve synergistic and coordinated management between the eye and the eyelid. There is a significant improvement in ocular healing with early excision and grafting of eyelids after sulfuric acid burn.

Corneal haze post photorefractive keratectomy

Corneal haze represents subepithelial corneal fibrosis, a manifestation of a pathological healing process. It occurs as a result of an epithelial-stromal lesion involving a break in the epithelial barrier. It is an inflammatory response that involves the migration, multiplication and differentiation of keratocytes into mature myofibroblasts, causing loss of corneal transparency. Although it is a transient phenomenon, this complication is feared following refractive photokeratectomy (PRK), because it can cause alterations in the quality of vision, refractive regression and decreased visual acuity. The severity of these symptoms is correlated with the severity of the corneal haze, which can be assessed clinically or by objective means such as corneal densitometry measurement. The frequency and severity of corneal haze increase with the depth of photoablation in PRK and are therefore increased during the treatment of severe ametropia. Considering that no consensus exists, the application of mitomycin C (MMC) intraoperatively and topical corticosteroids postoperatively are conventionally used to inhibit collagen synthesis, sometimes in combination with various protocols depending on the center or surgeon. This review of the literature reports the current knowledge on corneal haze, in order to better understand it and optimise its prevention in the context of a decreased MMC supply, which has occurred in the past and could recur in the future.

[Refractive surgery for hyperopia]

Hyperopia is a refractive error in which light is focused behind, instead of on, the retina. Clear vision can be obtained by accommodation, but in the long run, this results in eye strain. Hyperopia can be classified as low [≤2.00 diopters (D)], moderate (2.00-4.00 D) and high (>4.00 D). Detailed preoperative evaluation is necessary and essential to obtain good postoperative results. Various surgical techniques can be proposed to correct this ametropia. The main techniques used act either by modifying the corneal curvature with the Excimer laser or by implanting a phakic intraocular lens. The anatomical peculiarities of the hyperopic eye (small corneal diameter, short axial length, narrow anterior chamber or large kappa angle) make refractive surgery for hyperopia a considerable challenge. Large optical ablation zones now allow correction of high hyperopia by reducing the risks of optical aberrations and regression. The patient must be informed and understand the postoperative course, which differs from that of surgery for myopia.

3D-printed shields for slit lamps produced during the COVID-19 pandemic

Additive manufacturing has been extensively used during the COVID-19 pandemic to design and produce protection equipment. During clinical examinations using slit lamps, ophthalmologists are at risk of being contaminated by the SARS-CoV-2 virus, and the device itself is exposed to viral contamination. Several solutions have already been proposed for fixing transparent shields on the physician side. Here we propose a 3D-printed device fixed on the chin rest on the patient side, aiming at limiting viral spread both on the lamp itself and towards the physician.

[Signs, symptoms, and clinical forms of cataract in adults]

Cataract is a partial or total opacification of the crystalline lens. In adults, cataract is acquired; the most common form is the age-related cataract. Assessment of the functional impact of a cataract is clinical. The common symptom is loss of visual acuity, but other symptoms (photophobia, monocular diplopia, myopic shift, change in color vision, etc.) may be found depending on the anatomical distribution of the opacities (nuclear, posterior subcapsular, cortical). Diagnosis is based on slit-lamp examination after pupillary dilation. This allows classification of the opacities according to their anatomical distribution and can help direct any etiologic work-up. A number of potential causes should be ruled out before concluding that a cataract is age-related. Cataracts may be iatrogenic, associated with other ocular or systemic disease, or induced by ocular trauma. Knowledge of the signs, symptoms, and clinical forms of cataract helps to establish proper indications for cataract surgery in accordance with preferred practice patterns in ophthalmology.

[Functional results and prognostic factors in open-globe ocular trauma with presenting visual acuity of no-light perception]

PURPOSE

To analyse the clinical ocular characteristics and determine prognostic factors for functional recovery in eyes presenting with no light perception (NLP) after open globe ocular trauma.

MATERIALS AND METHODS

In this retrospective study were included all the patients with no light perception after open globe trauma who presented to Amiens University Hospital between October 2014 and June 2018.

RESULTS

Fifteen eyes of 15 patients were included in this study. The main mechanism of the trauma was globe rupture (80 %, n=12). The most common location was zone III (66 %, n=10). The wound size was greater than 10mm in 9 patients (60 %). The ocular lesions included expulsion of the crystalline lens or posterior chamber intraocular lens, hyphema, retinal detachment, vitreous hemorrhage and ciliochoroidal lesions. Damage to the ciliary body was a negative prognostic factor for functional recovery (P=0.04). Nine patients remained with no light perception, whereas 6 patients experienced an improvement in visual acuity (2.3 logMAR in 3 patients, 0.7 logMAR in 1 patient, 0.4 logMAR in 1 patient and 0.2 logMAR in 1 patient). These 6 patients had undergone posterior vitrectomy due to vitreoretinal involvement (P<0.001).

CONCLUSION

In the case of open globe trauma with no light perception on presentation, a functional recovery is possible if there is no irreversible anatomical damage.

[Cyclodialysis, a therapeutic challenge: Review of the literature on current practices]

INTRODUCTION

Cyclodialysis is a rare condition that is difficult to manage. We present the case of a woman with a cyclodialysis complicated by chronic hypotony requiring two surgeries to achieve reattachment of the ciliary body. We also report the results of a review of the literature regarding the treatment of this condition.

DESCRIPTION

This is a 46-year-old woman with history of trauma to the right eye. Examination revealed an intra-ocular pressure (IOP) of 7mmHg, a shallow anterior chamber and signs of chronic hypotony on fundus examination (vascular tortuosity, hypotony maculopathy) due to an extensive 360° cyclodialysis, confirmed by ultrasound biomicroscopy. Transcleral cryotherapy as a first-line approach did not achieve reattachment of the ciliary body. Secondary pars plana vitrectomy with gas tamponade (C2F6) reattached the ciliary body and restored the intraocular pressure (12mmHg) and normal fundus appearance. The patient recovered corrected visual acuity of 20/20.

DISCUSSION

To our knowledge, there is no standardized management for cyclodialysis. The study of the literature available on the Medline database showed that direct cyclopexy remains the most common treatment, followed by vitrectomy with internal tamponade. Neither the extent nor the duration of the cyclodialysis can predict the visual recovery, which can be major even after weeks of hypotony.

CONCLUSION

The management of cyclodialysis is not well-defined; it remains a true therapeutic challenge.

[Hereditary color vision deficiency: Physiology, classification, diagnosis and application to aeronautics]

Hereditary color vision deficiency affects 9% of men and 0.5% of women. It is often unrecognized and diagnosed late, which can interfere with the professional careers of these patients. Most color vision deficiencies are related to X chromosome involvement and concern the red-green chromatic axis. They are secondary to dysfunction of an L or M cone (protanomaly or deuteranomaly) or to the absence of an L or M cone (protanopia or deuteranopia). Color vision deficiency screening and assessment can be done by confusion tests or equalization tests, but also by ergonomic tests, professional tests that assess the aptitude for a given profession.

Color Vision Tests in Pilots' Medical Assessments

INTRODUCTION

The aim of this study was to evaluate the ability of eight color vision tests to screen for and accurately measure hereditary color-deficiency in order to improve color vision assessment methods for aircraft pilots.

METHODS

This prospective study included 29 color-deficient subjects and 23 healthy subjects. All performed the following tests: Ishihara plates, Farnsworth D15, Lanthony desaturated 15 Hue, Munsell 100 Hue, Beyne and Fletcher-Evans CAM lanterns, Nagel anomaloscope, and the Color Assessment and Diagnosis (CAD) test. The sensitivity and specificity of color-deficiency diagnosis were evaluated for each test, as well as the test's relevance for assessing aircraft pilots.

RESULTS

The Ishihara plate test demonstrated a sensitivity of 0.97 and a specificity of 1.00 for color-deficiency screening. The CAD test and anomaloscope showed both a sensitivity and specificity of 1.00. The Beyne lantern, Fletcher lantern, Farnsworth D15, and the Lanthony 15 Hue tests all showed a specificity of 1.00 and sensitivities of, respectively, 0.69, 0.97, 0.58, and 0.79. During aircraft pilot selection tests, the CAD test classified 10% of color-deficient subjects as safe to fly, the anomaloscope 17%, and the Beyne and Fletcher lantern tests, respectively, 31% and 3%.

DISCUSSION

The discrepancy in results confirms that current color vision test protocols need to be reassessed. The CAD test could be an interesting alternative to the series of tests used to assess flight crew, but it seems more selective than current tests.Marechal M, Delbarre M, Tesson J, Lacambre C, Lefebvre H, Froussart-Maille F. Color vision tests in pilots' medical assessments. Aerosp Med Hum Perform. 2018; 89(8):737-743.

Central PresbyLASIK for Hyperopia and Presbyopia Using Micro-monovision With the Technolas 217P Platform and SUPRACOR Algorithm

PURPOSE

To analyze the refractive outcomes and satisfaction of presbyopic hyperopes treated with central presbyopicLASIK (presbyLASIK) with induced micro-monovision.

METHODS

This retrospective study included 74 eyes of 37 patients treated with central presbyLASIK with micro-monovision using the Technolas 217P excimer laser (Technolas Perfect Vision GmbH, Munich, Germany) between June 2011 and March 2014. Study parameters included uncorrected distance visual acuity (UDVA) and uncorrected near visual acuity (UNVA), aberrometry, the central steep zone, and patient satisfaction.

RESULTS

Median age was 54.3±4 years (range: 46 to 63 years). Mean postoperative spherical equivalent refraction was 0.00±0.58 diopters (D) for dominant eyes and -0.51±0.54 D for non-dominant eyes. Mean binocular UDVA was 0.01±0.10 logMAR (Snellen 20/20) at 6 months and -0.01±0.05 logMAR (Snellen 20/19) at 1 year postoperatively. Mean binocular UNVA was 0.18±0.14 logMAR (Parinaud 2) (Jaeger 1) at 6 months and 0.18±0.12 logMAR (Parinaud 2) (Jaeger 1) at 1 year postoperatively. At 6 months, 79.31% of patients achieved 20/25 and could read Parinaud 2 (Jaeger 1) binocularly. At 1 year, 84.21% of patients achieved 20/25 and could read Parinaud 2 (Jaeger 1) binocularly. The mean central steep zone was 2.35±1.00 D. There were significantly more negative spherical aberration and vertical coma in the central 5 mm postoperatively (P<.05). The re-treatment rate was 6.75%. Eighty-three percent of these patients did not need any glasses for distance and near vision.

CONCLUSIONS

This procedure may improve functional near, intermediate, and distance vision in presbyopic patients with low and moderate hyperopia.

[Comparison of two different surgical treatments of presbyopia for hyperopic patients over 55 years old: Presbylasik (Supracor) and Prelex (presbyopic lens exchange)]

INTRODUCTION

The management of presbyopic patients is a medical, surgical and economic issue. We wondered which procedure, whether a Presbylasik technique called Regular Supracor or the intraocular surgery of clear lens replacement by a trifocal diffractive lens (presbyopic lens exchange [Prelex]), provided the best results (in visual acuity and satisfaction) for our hyperopic and presbyopic patients between 55 and 70. The aim of this study was to compare the safety and efficacy of the two techniques (at one week and three months) and to assess patients' quality of life.

METHODS

This study is a retrospective monocentric clinical trial conducted between June 2011 and March 2014, on 21 hyperopic presbyopic patients (mean age 60.9 years), in the "hôpital d'instruction des armées-Percy" (Clamart); 13 patients underwent the corneal treatment of Presbylasik (with the Intralase FS60 femtosecond laser [AMO, USA] and the Technolas 217P excimer laser [Technolas Perfect Vision, GmbH] following the Zyoptix Tissue-Saving algorithm adjusted with a nomogram and the Regular Supracor mode), and 8 patients underwent clear lens extraction (Prelex), through bimanual phacoemulsification and implantation of diffractive trifocal intraocular lenses (Finevision Micro F, PhysIOL(*)).

RESULTS

Mean uncorrected binocular distance and near vision visual acuity in the Supracor group were respectively 0.03 (-0.2-0.1) LogMar and 0.23 (0.06-0.36) one week postoperatively and 0.031 (-0.2-0.1) and 0,166 (0.06-0.36) three months postoperatively. In the Prelex group, the mean uncorrected one week binocular VA was 0.025 (0-0.1) for distance vision and 0.165 (0.06-0.18) for near distance and the three months visual acuity was 0 (-0.1-0.1) and 0.105 (0.06-0.18) for distance and near vision. All Prelex patients were spectacle-free at all distances, whereas 4 Supracor patients required spectacles for near vision postoperatively. Seven of 11 patients in the Supracor group and 100% of the Prelex patients were completely satisfied. Both groups experienced halos, but patients reported more halos in the Prelex group (75%). One eye required intraocular lens exchange and four eyes (16.7%) required a new corneal procedure in the Supracor group.

CONCLUSION

Both surgeries are safe and effective modalities in the management of hyperopic and presbyopic patients. However, the Prelex procedure seems to be more appropriate for patients over 55 years of age.

Demarcation line evaluation of iontophoresis-assisted transepithelial corneal collagen cross-linking for keratoconus

PURPOSE

To evaluate the visualization and depth of the demarcation line with anterior segment optical coherence tomography (AS-OCT) after iontophoresis-assisted transepithelial corneal collagen cross-linking (CXL).

METHODS

This prospective, consecutive, single center, non-randomized clinical study involved 15 eyes of 12 patients with keratoconus who underwent an AS-OCT scan (Spectralis; Heidelberg Engineering, Inc., Carlsbad, CA) to search for a demarcation line and its depth at 1 month after iontophoresis-assisted transepithelial CXL. AS-OCT scan measurements were performed by two independent examiners.

RESULTS

No intraoperative or postoperative complications were observed. Kappa coefficient estimation for operator agreement in demarcation line visualization (whether it was visualized) was 70.6%. The corneal stromal demarcation line was identified in 9 eyes (60%) by both examiners. Mean depth of the corneal stromal demarcation line was 246.67 ± 50.72 µm (range: 183 to 339 µm) for the first examiner and 241.89 ± 62.52 µm (range: 163 to 358 µm) for the second examiner. There were no statistically significant differences for the measurements of the paired comparisons between the two examiners (P = .61). The Pearson correlation coefficient between the measurements was 0.910.

CONCLUSIONS

Iontophoresis-assisted transepithelial CXL creates a demarcation line that can be visualized with AS-OCT, which seems less easily distinguishable and shallower than in conventional CXL. However, its depth and visualization seems to be more similar to conventional CXL than transepithelial CXL.