Leber's optic neuropathy I. Clinical studies

Abstract

A detailed ophthalmological study on 72 individuals at risk to develop Leber's Optic Neuropathy (L.O.N) has revealed that early signs may be present. These included usually non-specific signs such as tortuosity of the peripapillary capillaries as best seen on fluorescein angiography; hyperaemia and a hazy boundary of the disc; relative paracentral and central scotomata; abnormal VERs; and increases in the error score with the Farnsworth 100-Hue test. The only possibly specific sign may be tortuosity of the capillaries. This conclusion was reached by comparing the findings in individuals at risk with the results of examination of five patients seen during the acute phase of L.O.N. One of the persons at risk, who had many early signs, developed L.O.N. 6 months after being studied. In 7 of 13 carriers abnormalities were observed that resembled those seen in certain individuals at risk.

Studies on Leber's optic neuropathy III

“…It was calculated, as stated earlier, that in the group of 78 males at risk about 10 individuals are likely to be carrier of the gene. Minor ophthalmological abnormalities in at risk individuals, prior to the onset of the optic atrophy, have been observed by Stehouwer and Went [13,14] and Nikoskelainen et al [3,8].…”

“…The age range of the group of proven carriers is obviously higher, since they must have at least one affected child to be recognised as carrier, whereas in the persons-at-risk group only relatively young male individuals have been studied. Amongst the 78 persons in this group approximately 10 carriers of the gene for LON (future patients) can be expected; this figure is obtained analysing the position of all the at risk individuals in the pedigrees and the age related risk: based on an age at onset curve following Stehouwer and Went [13]. In all three groups (patients, carriers and persons at risk) there is a considerable excess of minor neurological abnormalities as compared with the respective control group.…”

“…In two preceding articles we have reported studies from Leiden in 90 individuals originating from the 27 pedigrees originally published by van Senus and from two other pedigrees which have come to our attention after 1963 [13,14]. These consisted of 72 individuals at risk to develop LON, 13 carriers and 5 patients during the acute onset phase of the optic atrophy.…”

Leber's optic neuropathy II. Fluorescein angiographic studies

“…A general introduction on L.O.N., including early signs, has been given in the previous paper (Stehouwer and Went, 1982) in which the results of ophthalmological studies are presented. appear as a circumpapillary telangiectatic microangiopathy and swelling of the nerve fibre layer around the optic disc, but without late fluorescein staining of the disc (Smith et al, 1973;Nikoskelainen et al, 1977).…”

Leber hereditary optic neuropathy (LHON): a mitochondrial disease with unresolved complexities

“…Very careful studies have since been undertaken in Denmark (Seedorff, 1985), Finland (Nikoskelainen et al, 1987(Nikoskelainen et al, , 1995Lamminen et al, 1997), England Riordan-Eva and Harding, 1995;Chalmers et al, 1996), the USA (Novotny et al, 1986), Australia (Wallace, 1970), the Netherlands (Stehouwer and Went, 1982;Bruyn et al, 1991Bruyn et al, , 1992De Vries et al, 1996;Oostra, 1996;Oostra et al, 1996), and Japan (Imachi, 1969;Nakamura et al, 1992). Howell (1997) does not believe that extra-ophthalmological abnormalities form an essential part of LHON.…”