Diagnosis and management of keratoconus by eye care practitioners in Kenya

Vision Improvement in Keratoconus Patients Trained With Perceptual Learning: A Randomized Controlled Trial

PURPOSE

To investigate the effectiveness and maintenance of perceptional learning (PL) on vision improvement in keratoconus (KC) patients corrected with spectacles.

DESIGN

Randomized, double-blind clinical trial.

METHODS

Non-progressive KC patients 9 years of age or older who had best spectacle-corrected distance visual acuity (CDVA) of 0 to 1.0 logMAR (Snellen equivalent range 20/20 to 20/200) and who were contact lenses intolerant were enrolled. Eligible subjects were randomized into PL and control groups to receive PL and placebo training for 3 months, respectively. Spectacle-corrected visual acuity, contrast sensitivity function (CSF), stereoacuity, and visual functioning and quality of life were measured at baseline, 3 months, and 6 months of follow-up. Statistics were analyzed following the intention-to-treat principle.

RESULTS

After 3 months of training, the CDVA of patients in the PL group improved as compared to the placebo group (0.17 ± 0.15 logMAR vs 0.02 ± 0.06 logMAR; P = .0006). Eight of 17 (47.06%) patients in the PL group reached CDVA improvement ≥2 lines (P = .0010). This improvement persisted for at least 6 months (from baseline) as compared to the placebo group (0.17 ± 0.17 logMAR vs 0.01 ± 0.07 logMAR; P = .0011). The increase in CSF in the PL group mainly was found for moderate spatial frequency (0.11 ± 0.17 log units at 3 cpd; 0.12 ± 0.19 log units at 6 cpd). Linear regression indicated that patients with worse initial CDVA achieved better gains in CDVA after PL (P = .009). No side effects were observed, and no subjects withdrew from the study because of training difficulties.

CONCLUSIONS

Three-month PL improved vision in KC patients, and the improvement was maintained after 3 months of treatment cessation. The results indicate that PL may be a promising therapy for KC patients with unsatisfied spectacle-corrected visual acuity.

Retinoscopes: Past and present

BACKGROUND

Retinoscopy is arguably the most important method in the eye clinic for diagnosing and managing refractive errors. Advantages of retinoscopy include its non-invasive nature, ability to assess patients of all ages, and usefulness in patients with limited cooperation or communication skills.

AIM

To discuss the history of retinoscopes and examine current literature on the subject.

METHODS

A search was conducted on the PubMed and with the reference citation analysis (https://www.referencecitationanalysis.com) database using the term "Retinoscopy," with a range restricted to the last 10 years (2013-2023). The search string algorithm was: "Retinoscopy" (MeSH Terms) OR "Retinoscopy" (All Fields) OR "Retinoscopes" (All Fields) AND [(All Fields) AND 2013: 2023 (pdat)].

RESULTS

This systematic review included a total of 286 records. Publications reviewed iterations of the retinoscope into autorefractors, infrared photo retinoscope, television retinoscopy, and the Wifi enabled digital retinoscope.

CONCLUSION

The retinoscope has evolved significantly since its discovery, with a significant improvement in its diagnostic capabilities. While it has advantages such as non-invasiveness and broad applicability, limitations exist, and the need for skilled interpretation remains. With ongoing research, including the integration of artificial intelligence, retinoscopy is expected to continue advancing and playing a vital role in eye care.

Barriers to the Diagnosis and Management of Keratoconus Among Optometrists in Kenya

Background

Early diagnosis and management of keratoconus (KC) are important for limiting visual complications of the disease. This study aimed to explore the perspectives of optometrists on the barriers to effective diagnosis and management of KC in Kenya.

Methods

An online questionnaire was distributed to optometrists in Kenya to collect data on barriers to the diagnosis and management of KC.

Results

The majority (60.9%) of optometrists were confident in retinoscopy and subjective refraction. Fewer were confident in the use of keratometers (46.4%) and corneal topographers (24.9%) and in the fitting of rigid gas permeable (RGP) contact lenses (25.0%). The most commonly reported barriers to improving their knowledge and skills were, limited continuous professional development opportunities (87.4%), high costs of conferences (86.1%) and the lack of diagnostic tools (79.5%). Impediments cited to diagnosing and managing KC effectively were a lack of national guidelines (64.9%), patient education material (71.5%), equipment (58.9%) and RGP supply (68.2%) and cost (67.5%). Most commonly reported barriers related to patients were compliance (91.4%), affordability (90.7%), RGP discomfort (89.4%), willingness to pay (88.1%) and the lack of patient education about KC (87.4%).

Conclusion

This study showed that the lack of national guidelines, essential equipment and adequate practitioner knowledge and skills were barriers to KC diagnosis and management. Regulation of optometric education and clinical practice, development of national guidelines for diagnosis and management of KC, up-skilling of practitioners and cost-effective solutions for equipment procurement and maintenance may improve both access to, and quality of, care to patients with KC.

Prevalence and clinical characteristics of vernal keratoconjunctivitis in sub-Saharan Africa

PURPOSE OF REVIEW

Vernal keratoconjunctivitis (VKC) is a chronic bilateral allergic inflammatory disease of the conjunctiva and cornea that affects children and young adults, especially in sub-Saharan Africa. A limbal form (tropical endemic limbo conjunctivitis) is thought to be more common in the tropics where research on this vision-impairing condition is scanty. We sought to review current literature from sub-Saharan Africa, with a focus on the prevalence of VKC and its clinical presentation.

RECENT FINDINGS

There is a variable prevalence of VKC in SSA, up to 32.9% of children, especially in male individuals less than 5 years old, and has been diagnosed in a 4-month-old baby. Associated factors include exposure to dust, personal and family history of atopy, Vitamin D3 deficiency and HIV. The mixed form of VKC is the most frequent form seen and conjunctival pigmentation might be an early diagnostic sign.

SUMMARY

Childhood screening programs for VKC should be established to reduce the morbidity, decreased quality of life and school absenteeism that is seen in these patients. VKC-related research should be encouraged in this milieu to bring to light the particularities of VKC in SSA.

Vernal Keratoconjunctivitis: A Systematic Review

Vernal keratoconjunctivitis (VKC) is a chronic, bilateral corneal and conjunctival problem which typically presents in young individuals. VKC is characterized by itching, photophobia, white mucous discharge, lacrimation, foreign body sensation, and pain due to corneal involvement of shield ulcers. Vernal keratoconjunctivitis is categorized within ocular diseases. The diagnosis is clinical, as no sure biomarkers pathognomonic of the disease have yet been identified. The VKC therapy relies on different types of drugs, from antihistamines and topical steroids to cyclosporine or tacrolimus eye drops. In extremely rare cases, there is also the need for surgical treatment for the debridement of ulcers, as well as for advanced glaucoma and cataracts, caused by excessive prolonged use of steroid eye drops. We performed a systematic review of the literature, according to PRISMA guideline recommendations. We searched the PubMed database from January 2016 to June 2023. Search terms were Vernal, Vernal keratoconjunctivitis, and VKC. We initially identified 211 articles. After the screening process, 168 studies were eligible according to our criteria and were included in the review. In this study, we performed a systematic literature review to provide a comprehensive overview of currently available diagnostic methods, management of VKC, and its treatments.