Hyperopia is a very common refractive error affecting adults but mostly occurring in children. To clarify, it’s a condition where an object image is focused behind the neurosensory retina which leads to a blurry vision up close. So, it’s important to avoid future complications via treatment and assessment which we will mention below.

What causes hyperopia?

You must know that everyone is born hyperopic at first, and that changes when we age to become either emmetropic or myopic. But if there exist a family history of hyperopia, it’s most likely to persist as you age. Above all, if you are hyperopic, you must seek treatment to prevent further eyesight dilemmas such as amblyopia and tropia. When there’s no conclusive and specific cause, there’s 4 types of the condition with each caused by a different scenario.

• Axial hyperopia or simple hyperopia is the most common type and is caused by eyeball anterior-posterior axial shortening. Notably, 3 diopters of hyperopia are caused by just 1 mm axial decrease in length.
• Curvature hyperopia is caused by flat lens or cornea or both; thus, 6 diopters of hyperopia is the result of 1 mm increase in the radius of curvature.
• Index hyperopia is due to the crystalline lens’s refractive index change which gradually deviates to the periphery rather than staying at the center. This type occurs in diabetic patients or old people.
• Positional hyperopia or aphakia or ocular pathologic conditions. These are the result of faulty position or the absence of crystalline or the intraocular lens leading to aphakic zone in the refractive media. Ocular pathologies can be a reason behind hyperopia as well. Such pathologies are microphthalmos, nanophthalmos or aniridia.

There’s way more reasons behind hyperopia such as 16p11.2 microdeletion, MYRF gene mutation, smoking while pregnant, hyperglycemia, long space missions, Kenny syndrome, Heimler syndrome, Larsen syndrome, X-linked retinoschisis...

Hyperopia can be asymptomatic:

The ciliary muscle or musculus ciliaris being able to move the pupil and lens, gives extra vision accommodation. Therefore, this allows some patients to see better without any difficulty.

Symptoms of hyperopia:

• Eyes deviation where both or one of the eyes deviate from center, mostly inward deviation (esotropia) in young children.
• Asthenopia which is the result of prolonged accommodative effort, and it’s characterized by headache and eyes tiredness.
• Vision dimness where near objects are blurry if not corrected with maximum accommodative effort.
• Vision gets blurry suddenly also called pseudo-myopia, it’s common with teenagers after long reading using prolonged accommodative effort.
• Recurrence of internal or external Hordeolum (red bump) or Conjunctivitis, and that’s due to rubbing eyes with non clean hands leading to inflammation.
• Crossed eye sensation after long accommodation effort with no diplopia.
• Premature presbyopia which is the loss of the ability to focus on objects that are close. This usually occurs for people in the early or mid 40s.

Parents role in child hyperopia:

If a child shows signs of hyperopia, or the family has a genetic history with the disease, the parents should consult a specialist early before. Ignoring the child condition might lead to crossed eyes (strabismus) or lazy eye (amblyopia). Besides, studies prove that smoking while pregnant makes it more likely for the child to have hyperopia. Moreover, its the parents that keeps up every 3 to 6 months with regular testing and re-evaluation of the child eyes condition, let alone the glasses treatment and amblyopia exercises.

Diagnosis:

For the indication of hyperopia or other associated eye problems, many methods exist such as visual acuity, fundoscopy, diffuse light examination, strabismus examination, and retinoscopy or refraction.

Hyperopia treatment:

1. Optical correction by biconvex lenses (glasses)
2. Surgery 

• Incisional refractive procedure such as hexagonal keratotomy and Lamellar refractive procedure
• Laser refractive procedure such as thermal laser keratoplasty
• Hyperopic photorefractive keratectomy (PRK)
• Hyperopic LASIK
• Intraocular Procedures
• (LASEK) Hyperopic laser sub epithelial keratomileusis
• Hyperopic epiploic LASIK (EPI-LASIK)
• Hyperopic customized-LASIK (C-LASIK)
• Other refractive procedures such as Conductive keratoplasty (CK) and Small incision lenticule extraction (SMILE)         

What to do after hyperopia surgery?

After kerato-refractive surgeries or laser surgeries, dark glasses or eye patches (CK), antibiotics for 5-7 days, artificial tear substitutes all must be used. Cyclosporine A is great to help with dry eyes due to surgery. Furthermore, it’s necessary to check with a specialist to avoid complications and revaluate refraction.

Complications:

• Amblyopia
• Squinting
• Central serous chorioretinopathy (CSCR)
• Anterior ischemic optic neuropathy (AION)
• Age-related macular degeneration (ARMD)
• Angle-closure disease
• Retinal vein occlusion
• Nanophthalmos/posterior microphthalmos
• Uveal effusion syndrome

References:

-Akhtar F, Bokhari SRA. Apoptosis. [Updated 2021 May 16]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-.