Sehbehinderung und Blindheit bei Kindern in einer malawischen Blindenschule

Zusammenfassung

Hintergrund: Bestimmung der anatomischen Klassifikation der häufigsten Gründe für eine Sehbehinderung oder Blindheit von Kindern, die eine integrierte Blindenschule in Malawi besuchen. Vergleich der erhobenen Daten mit älteren malawischen Blindenschulstudien.

Methode: Im September 2011 wurden Kinder der integrierten Gesamtschule für Blinde an einem Tag direkt vor Ort untersucht. Verwendet wurde das Standardprotokoll der WHO zur Untersuchung von Blinden und Sehbehinderten. Der Visus des jeweils besseren Auges wurde in diesem WHO-Protokoll notiert.

Ergebnisse: 55 Kinder zwischen 6 und 19 Jahren wurden untersucht. 39 (71 %) Jungen und 16 (29 %) Mädchen. 38 (69%) waren blind [BL], 8 (15 %) stark sehbehindert [SVI], 8 (15 %) sehbehindert [VI], und ein Kind (1,8 %) hatte keine Sehbehinderung [NVI]. Die häufigsten Erblindungsursachen nach anatomischer Klassifikation waren der Sehnerv (16 %) und die Netzhaut (16 %), gefolgt von Linse (15 %), Hornhaut (11 %) und Erkrankungen des Bulbus (11 %), Pathologien der Uvea (6 %) und kortikale Blindheit (2 %). Die exakte Ätiologie von Blindheit und Sehbehinderung konnten bei den meisten Kindern nicht bestimmt werden. Albinismus zählte mit 13 % (7/55) zu den häufigsten Ursachen einer Sehbehinderung. 24 % der Ursachen wären vermeidbar gewesen: refraktive Schwachsichtigkeit bei Pseudophakie-Patienten und Hornhautnarben.

Schlussfolgerung: Optikusatrophie, retinale Erkrankungen (zumeist Albinismus) und Katarakte sind die Haupterblindungsursachen in einer integrierten Blindenschule in Malawi. Eine Erblindung infolge von Hornhautnarben wurde als vierthäufigster Grund festgestellt, 35 Jahre zuvor war dies der häufigste Grund. Die kongenitale Katarakt bzw. ihre postoperativen Folgen sind der häufigste vermeidbare Grund einer Sehbehinderung oder Erblindung.

Abstract

Purpose: The aim of this study was to determine the anatomic sites of severe visual impairment and blindness in children in an integrated school for the blind in Malawi, and to compare the results with those of previous Malawian blind school studies.

Methods: Children attending an integrated school for the blind in Malawi were examined in September 2011 using the standard WHO/PBL eye examination record for children with blindness and low vision. Visual acuity [VA] of the better eye was classified using the standardised WHO reporting form.

Results: Fifty-five pupils aged 6 to 19 years were examined, 39 (71 %) males, and 16 (29 %) females. Thirty eight (69%) were blind [BL], 8 (15 %) were severely visually impaired [SVI], 8 (15 %) visually impaired [VI], and 1 (1.8 %) was not visually impaired [NVI]. The major anatomic sites of visual loss were optic nerve (16 %) and retina (16 %), followed by lens/cataract (15 %), cornea (11 %) and lesions of the whole globe (11 %), uveal pathologies (6 %) and cortical blindness (2 %). The exact aetiology of VI or BL could not be determined in most children. Albinism accounted for 13 % (7/55) of the visual impairments. 24 % of the cases were considered to be potentially avoidable: refractive amblyopia among pseudophakic patients and corneal scaring.

Conclusions: Optic atrophy, retinal diseases (mostly albinism) and cataracts were the major causes of severe visual impairment and blindness in children in an integrated school for the blind in Malawi. Corneal scarring was now the fourth cause of visual impairment, compared to being the commonest cause 35 years ago. Congenital cataract and its postoperative outcome were the commonest remedial causes of visual impairment.

Schlüsselwörter

Katarakt - Kinderophthalmologie - Hornhaut - Blindenschule - Malawi - Afrika

Key words

cataract - paediatric ophthalmology - cornea - school for the blind - Malawi - Africa

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