Susann Andersson

Ophthalmological findings in children and young adults with genetically verified mitochondrial disease

Aim: To describe ophthalmological phenotypes in patients with mitochondrial disease and known genotypes. Methods: A retrospective study was performed on 59 patients (29 male, 30 female) with a mean age of 11.8 years who had mitochondrial disease with known DNA mutations. Fifty-seven of the 59 subjects underwent a detailed ophthalmological examination including visual acuity (VA), eye motility, refraction, slit-lamp examination, ophthalmoscopy and, in almost one-half of the cases, a full-field electroretinogram (ERG). Results: Forty-six (81%) of the patients had one or more ophthalmological findings such as ptosis (n = 16), reduced eye motility (n = 22) including severe external ophthalmoplegia (n = 9), strabismus (n = 4), nystagmus (n = 9), low VA (n = 21), refractive errors (n = 26), photophobia (n = 4), and partial or total optic atrophy (n = 25). Pigmentation in the macula and/or periphery was noted in 16 patients. In 10/27 investigated individuals with full field ERG, retinal dystrophy was recorded in six different genotypes representing Kearns–Sayre syndrome (n = 5), Leigh syndrome (n = 1), Mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) (n = 1), Myoclonus epilepsy with red ragged fibres (MERRF) (n = 1), Leber hereditary optic neuropathy (n = 1) and mitochondrial myopathy (n = 1). Conclusion: The results show that a majority of patients with mitochondrial disorders have ophthalmological abnormalities. We recommend that an ophthalmological examination, including ERG, be performed on all children and adolescents who are suspected of having a mitochondrial disease.

Strabismus and Binocular Functions in a Sample of Swedish Children Aged 4–15 Years

Purpose: To investigate strabismus, head posture, nystagmus, stereoacuity, ocular motility, near point of convergence (NPC) and accommodative convergence to accommodation ratio (AC/A) in a sample of Swedish children. Methods: A prospective cross-sectional study was carried out on 143 children, 4–15 years of age. Results: Heterotropia was found in five children (3.5%), four with esotropia and one with exotropia. One child with esotropia had a slight overaction of both inferior oblique muscles. Heterophoria was found in 37 children (26%) at near and/or distance fixation and it was four times more common at near than at distance. In 29 children, heterophoria was found at one distance only and orthophoria at the other. Orthophoria at both near and distance fixation was noted in 101 children (70.5%). The near point of convergence was ≤6 cm in 97% of the children and 97% had stereoacuity of 60″ or better. In the whole group, the median AC/A ratio calculated with the heterophoria method was 5.6/1 prism diopters/diopters (PD/D) and with the gradient method, 1.3/1 PD/D. No anomalous head postures or nystagmus were observed and all children had normal versions. Conclusion: In this study, 143 well-defined children were investigated with a battery of accurately described tests, commonly used in clinical practice. These results are in agreement with those of other studies examining one or few variables in larger populations and the authors therefore conclude that their results may be used for comparisons with different patient groups.

Vision in children with hydrocephalus

Hydrocephalus in children has many aetiologies, and can cause multiple ophthalmic and visual disorders. This study sets out to detect and quantify visual and visuoperceptual dysfunction in children who have received surgical treatment for hydrocephalus with and without myelomeningocele, and to relate the results to the associated diagnoses and results from a comparison group. Seventy-five school-aged children (41 males, 34 females) with surgically-treated hydrocephalus and 140 comparison children (76 males, 64 females) matched for age and sex underwent comprehensive ophthalmologic examination. Median age at examination was 9 years and 4 months (range 7 y 4 mo-12 y 10 mo). Visual function deficits were identified in 83% (62/75) of the children with hydrocephalus. Visual impairment (binocular visual acuity <0.3) was found in 15% (11/73; comparison group 0%) but in none with myelomeningocele. Strabismus was found in 69% (51/74; comparison group 4% [5/140], p < 0.001), and refractive errors were found in 67% (47/70; comparison group 20% [28/140], p < 0.001). Cognitive visual dysfunction was identified in 59% (38/64; comparison group 3% [4/140], p < 0.001). These disorders were identified in various combinations and comprised impaired ability to plan movement through depth (e.g. going down a stair), impaired simultaneous perception, impaired perception of movement, impaired orientation, and (least frequently) impaired recognition. In this study, children with hydrocephalus associated with myelomeningocele were least commonly affected. Visual disorders were most frequent in those with epilepsy, cerebral palsy, and/or cognitive disability.

Strabismus, binocular functions and ocular motility in children with hydrocephalus.

Purpose To investigate heterotropia, heterophoria, head posture, nystagmus, stereo acuity, ocular motility and near point of convergence (NPC) in children with hydrocephalus treated surgically before 1 year of age. In addition, the effects of being born with hydrocephalus, the effect of the etiology of hydrocephalus, number of shunt revisions and the size of the ventricles on these variables were studied. Methods A population-based study was performed in 75 children and the results were compared with the results of an age- and sex-matched group (comp group) (n = 140). Results Heterotropia 68.9% (comp group 3.6%; p < 0.001), abnormal head posture 41.3% (comp group 0; p < 0.001), nystagmus 44.0% (comp group 0; p < 0.001), stereo acuity ≤60″ 33.8% (comp group 97.1%; p < 0.001) and ocular motility defects 69.7% (comp group 0.7%; p < 0.001) were more common among children with hydrocephalus than in the comparison group. Children with overt hydrocephalus at birth had significantly more heterotropia (p = 0.0006), esotropia (p = 0.002), abnormal head posture (p = 0.02) and motility defects (p = 0.003) compared to those with hydrocephalus developing during the first year of life. The etiology, number of shunt revisions and the size of the ventricles had no significant effect on any of the investigated variables. Conclusions Children with hydrocephalus surgically treated before the age of one year commonly present orthoptic abnormalities. The etiology of hydrocephalus, number of shunt revisions and ventricle size seem to be of minor importance compared with the age of onset of hydrocephalus with regard to the risk for orthoptic abnormalities.

Abnormal optic disc and retinal vessels in children with surgically treated hydrocephalus

Aims: To investigate the morphology of the optic disc and retinal vessels in children with surgically treated hydrocephalus. Methods: A prospective, population-based study was performed in 69 children (median age 9.6 years) with early surgically treated hydrocephalus. All children were examined by ophthalmoscopy. Additionally, optic disc and retinal vessel morphology was evaluated in 55 children by digital image analysis of ocular fundus photographs. Results: Optic atrophy was found in 10 of 69 children (14%). In comparison with a reference group, the median optic-disc area was significantly smaller (p = 0.013) in the children with hydrocephalus. There was no corresponding difference in cup area, so the rim area was significantly smaller in the hydrocephalic children (p = 0.002). Children with hydrocephalus had an abnormal retinal vascular pattern, with significantly straighter retinal arteries and fewer central vessel branching points compared with controls (p<0.001 and p<0.001, respectively). Conclusion: Hydrocephalus is associated with subnormal optic disc and rim areas and an abnormal vascular pattern, indicating a pre/perinatal disturbance of the development of these structures. A promising finding is that the frequency of optic atrophy in the present study was lower than previously reported, most likely reflecting improved perinatal care and better regulation of the intracranial pressure.

Ocular dimensions in relation to auxological data in a sample of Swedish children aged 4–15 years

The purpose was to characterize normal growth patterns of ocular and optical components and to relate them to auxological data in a sample of Swedish children aged 4–15 years.

Ophthalmological characteristics in children with Leigh syndrome – A long‐term follow‐up

To describe ophthalmological characteristics in children with Leigh syndrome (LS), an inherited, progressive, mitochondrial encephalomyopathy, at diagnosis and over time, and relate the results to causative genetic mutations.