A person with aphakia wearingcataract glasses, with extremely thick lenses to correct the typical extreme farsightedness. Before in-eye lens replacement was available, such glasses were much more common.
Aphakia is the absence of thelens of theeye, due to surgical removal, such as incataract surgery, aperforating wound orulcer, orcongenital anomaly. It causes a loss of ability to maintain focus (accommodation), high degree of farsightedness (hyperopia),[1] and a deepanterior chamber. Complications include detachment of thevitreous orretina, andglaucoma. Babies are rarely born with aphakia. Occurrence most often results from surgery to remove a congenitalcataract. Congenital cataracts usually develop as a result of infection of the fetus or genetic reasons. It is often difficult to identify the exact cause of these cataracts, especially if only one eye is affected.
People with aphakia have relatively smallpupils and their pupils dilate to a lesser degree.[2]
Hypermetropia: Without the focusing power of the lens, the eye becomes veryfarsighted.[citation needed]
Loss of accommodation: Since the lens and itszonules are responsible for adjusting the focus of vision to different lengths, patients with aphakia will have a total loss ofaccommodation.[citation needed]
Defective vision: High degree hypermetropia and total loss of accommodation cause defective vision for both distance and near.[citation needed]
Cyanopsia: Absence of lens cause cyanopsia or blue vision.[1] Some individuals have said that they perceive ultraviolet light, invisible to those with a lens, as whitish blue or whitish-violet.[3][4]
Spectacle intolerance: Due to imagemagnification (up to 30%),optical aberration, prismatic effect and roving ring scotoma, spectacles are not well tolerated by aphakic patients.[6] Due tounequal refractive power between the eyes, wearing spectacles with single-eye aphakia may causedouble vision.[6]
Glaucoma: Secondary angle closure glaucoma may occur due to vitreous prolapse.[7]
Surgical removal of a lens, mainly in cataract surgery, is the most common cause of aphakia.[1] Spontaneous traumatic absorption or congenital absence of lens matter is rare.[9][10] Traumatic subluxation or dislocation of a lens may cause it.[1]
^abcdefghKhurana, AK (2015). "Errors of refraction and accommodation".Comprehensive ophthalmology (6th ed.). Jaypee, The Health Sciences Publisher. pp. 37–38.ISBN978-93-86056-59-7.
^abcRamanjit, Sihota; Radhika, Tandon (2015).Parsons' diseases of the eye (22nd ed.). New Delhi, India: Elsevier.ISBN978-81-312-3819-6.OCLC905915528.
^Sowka, Joseph W. (November 2002). "Pupil block glaucoma from traumatic vitreous prolapse in a patient with posterior chamber lens implantation".Optometry (St. Louis, Mo.).73 (11):685–693.ISSN1529-1839.PMID12516797.
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