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M D Sanders

Publications and source records attributed to M D Sanders.

At least 37 records · Page 2Linked to original sources
PubMed1995

The clinical features of Leber's hereditary optic neuropathy defined by the presence of a pathogenic mitochondrial DNA mutation.

One hundred and seven patients from 79 families were defined as having Leber's hereditary optic neuropathy (LHON) by the presence of one of the mitochondrial DNA (mtDNA) mutations at positions 11778 (60 families), 3460 (seven families) or 14484 (12 families). Only half of the 11778 index patients had a history of similarly affected relatives; this proportion was higher with the 3460 (71%) and 14484 (100%) mutations. The ratios of affected male to female patients were 2.5:1 (11778), 2:1 (3460), and 5.7:1 (14484). Detailed clinical data were available for 79 patients from 55 families. Visual loss developed between the ages of 11 and 30 years in 69%, with a range of 6-62 years, and no significant differences between mutation groups or males and females. It was bilateral in all but two patients, to a median of counting fingers with a central scotoma, developing simultaneously in 22% and sequentially in 78%, with a median inter-eye delay of 8 weeks, and progressing in each eye over a period of 4-6 weeks. Nineteen patients had pain in an affected eye or on eye movements, and four experienced Uhthoff's phenomenon. Retinal microangiopathy was uncommon after 6 months from onset and was not detected in 36% of patients examined within 3 months of visual loss; the microangiopathy was particularly uncommon in the 14484 group. There was no difference in the overall visual outcome between the 11778 and 3460 groups with median final visual acuities of 1/60 and 3/60, respectively. Particularly severe visual loss occurred in one-third of women with the 11778 mutation, to vague perception of light or no perception of light in at least one eye. A multiple sclerosis-like illness was observed in 45% of females with the 11778 mutation. Prognosis was substantially better in the 14484 patients, with recovery to a final visual acuity of at least 6/24, in 71% of patients. Good visual outcome was strongly correlated with age at onset, all those with onset before 20 years having a final visual acuity better than 6/24 as opposed to only 2 out of 6 with later onset. Improvement in vision occurred as long as 4 years after onset. High alcohol and tobacco consumption, cranial or ocular trauma, young or old age at presentation, co-existing neurological disease, and recent childbirth with post-partum haemorrhage, all contributed to diagnostic difficulties in this series, usually in the absence of a family history. These problems were resolved by mtDNA analysis.

Adolescent↗
PubMed1995

Vision.

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Electroretinography↗
PubMed1994

Coagulation abnormalities in ischaemic optic neuropathy.

The aetiology of non-arteritic ischaemic optic neuropathy (ION) is multifactorial with local anatomical and systemic haemodynamic abnormalities both playing a role. A careful search for treatable vascular disease risk factors is required to allow rational therapy, to optimise the visual prognosis and to allow new insights into pathogenesis. We describe 7 cases in which there was an associated thrombophilic (prothrombotic) state; 4 had deficiencies of the physiological anticoagulants proteins C and S and antithrombin III and 2 had anti-phospholipid antibody (lupus anticoagulant) syndromes. A further patient had reduced levels of the physiological fibrinolytic agent tissue plasminogen activator (t-PA). In 5 patients other risk factors for small vessel occlusive disease were also present, and 4 had recurrent episodes of ION in the same eye. The visual prognosis in these patients may be improved by anticoagulation with warfarin.

Adult↗
PubMed1994

[Atypical presentation of Leber's optic neuropathy].

BACKGROUND: Leber's optic neuropathy (LON) is the phenotypic expression of an inherited disorder due to a mitochondrial DNA mutation. Numerous loci of a point mutation in the mitochondrial genome are reported: 3460, 4160, 11778, 14484 and, 15257. Typically visual loss occurs in young males and a positive family history is found. Peripapillary telangiectasias are reported to be diagnostic for the disease and cardiac conduction abnormalities are sometimes present. PATIENTS: We present six patients who lost vision in both eyes with neither family history of visual loss, typical fundus abnormalities, nor cardiac abnormalities. All were initially misdiagnosed as either anterior ischemic optic neuropathy, hereditary optic atrophy, thromboembolic disorder, toxic amblyopia, multiple sclerosis, traumatic optic neuropathy, or complicated papilledema. METHODS AND RESULTS: Diagnosis was possible in all six cases by mitochondrial DNA studies (five patients with 11778, one with 3460). Magnetic resonance imaging using short-time inversion recovery sequences demonstrated in three tested patients a hyperintense signal within the intraorbital portion of the optic nerve, enhancing after Gadolinium infusion. CONCLUSION: Presentation of LON can be atypical, i.e. occurring in a female, at an advanced age, without family history, without retinal telangiectasias, with other fundus findings, or with unilateral visual loss for prolonged period. Diagnosis of LON should be suspected in every patient with atypical visual loss secondary to an optic neuropathy of undetermined etiology and mitochondrial DNA studies should be performed. Magnetic resonance imaging can be helpful in such cases.

Adult↗
PubMed1994

Autosomal dominant cerebellar ataxia with pigmentary macular dystrophy. A clinical and genetic study of eight families.

We describe 54 members of eight families with a distinct autosomal dominant cerebellar ataxia associated with visual failure secondary to a pigmentary macular dystrophy. The presenting symptom was ataxia in two-thirds of patients and visual failure or both in the remainder. The macular abnormalities were often subtle in early cases, even in some with moderately reduced visual acuity. Other neurological features included pyramidal tract signs and a supranuclear ophthalmoplegia with progressive saccadic palsy. Ages of onset and clinical course were very variable, even within families, and included a rapidly progressive, infantile-onset phenotype. Pedigree analysis showed the existence of non-manifesting obligate carriers and anticipation in the offspring of affected fathers; transmission of the disease to severe, infantile-onset cases was always from an affected father. Similar genetic phenomena have been reported in myotonic dystrophy and Huntington's disease and it is likely that the gene mutation in this condition will similarly consist of an unstable trinucleotide repeat expansion.

Adolescent↗
PubMed1994

Optic nerve sheath decompression for the treatment of visual failure in chronic raised intracranial pressure.

The records of all patients undergoing optic nerve sheath decompression for visual failure in chronic raised intracranial pressure performed over a 15 year period have been reviewed. The aim was to study the visual outcome and relation to any shunting procedures. Fourteen patients (20 eyes) were identified in whom follow up information of at least one year was available. Eleven patients had benign intracranial hypertension (idiopathic intracranial hypertension) and three had dural venous sinus occlusive disease. Eight patients had unilateral surgery and six had bilateral surgery. Visual acuity and fields either improved or stabilised in 17 out of 20 eyes and three deteriorated. Of the eight patients undergoing unilateral surgery, the other eye remained stable in seven and deteriorated in one. Four patients required optic nerve sheath decompression despite previous shunting or subtemporal decompression. Five patients required shunts or subtemporal decompression after optic nerve sheath decompression because of persistent headache in three cases and for uncontrolled visual failure in two cases. No patients lost vision as a direct consequence of surgery. It is concluded that optic nerve sheath decompression is a safe and important therapeutic option in the management of chronic raised intracranial pressure complicated by visual loss. Vision can be saved after shunt failure, and in other cases may be maintained without the need for a shunt. Shunts may still be required, however, after optic nerve sheath decompression, especially for persistent headache.

Adult↗
PubMed1993

Macular ischaemia in posterior uveitis.

The commonest cause of visual morbidity in patients with posterior uveitis is cystoid macular oedema, which usually responds to immunosuppressive treatment. However, a small group of patients do not have a satisfactory visual outcome despite apparently adequate therapy. In a retrospective study of 345 angiograms of 135 patients with active non-occlusive retinal vasculitis 12 patients were identified by independent masked review as showing macular ischaemia on their fluorescein angiograms. Four patients had Behçet's disease, 4 sarcoidosis, and 4 idiopathic retinal vasculitis. Follow-up of these patients for an average of 36 months (range 6-120 months) showed that visual acuity failed to improve in 4 patients and dropped by an average of three lines Snellen in the other 8. We suggest that a poor visual outcome in some patients with posterior uveitis may be predicted by the presence of macular ischaemia on fluorescein angiography and that immunosuppressive therapy should be prescribed with caution in these patients.

Adult↗
PubMed1993

Midbrain angioma with disconjugate vertical gaze palsy.

Loss of depression in one eye with contralateral loss of elevation is rare. It has been attributed to a subnuclear lesion of the oculomotor nerve nuclear complex. We present a patient with these signs who has an arteriovenous malformation occupying his rostral midbrain. We argue that attributing these findings to a subnuclear lesion of the oculomotor nerve complex does not take into consideration the secondary, vertical action of the obliques.

Adult↗
PubMed1993

Churg-Strauss vasculitis presenting with severe visual loss due to bilateral sequential optic neuropathy.

A 44-year-old man with severe visual loss due to an acute bilateral sequential optic neuropathy is described, where the associated pulmonary disease and peripheral eosinophilia led to a diagnosis of Churg-Strauss syndrome (allergic angiitis). The mechanism of the optic neuropathy was most probably acute ischaemia of the anterior optic nerve due to direct involvement of the short posterior ciliary arteries by inflammatory disease of the vessel wall.

Adult↗
PubMed1993

Anterior visual system involvement in non-Hodgkin's lymphoma.

Non-Hodgkin's lymphoma may have ocular involvement but optic nerve and chiasmal disease is unusual. Determining the cause of the neuropathy in this group of patients presents major difficulties despite modern neuroimaging and immunocytochemistry. Two patients with NHL are presented; one had an anterior chiasmal syndrome and the other bilateral optic nerve involvement. The first patient was thought to have lymphomatous infiltration and the second a concomitant infection (progressive multifocal leucoencephalopathy). Toxic effects of therapy were considered but finally rejected. The importance of modern neuroimaging and the role of optic nerve biopsy are discussed.

Adult↗
PubMed1992

Late onset Leber's optic neuropathy: a case confused with ischaemic optic neuropathy.

A case is reported of a 63-year-old man with progressive central visual loss in one eye followed 11 months later by involvement of the fellow eye. A diagnosis of chronic ischaemic optic neuropathy was considered. However, despite a negative family history, the absence of electrocardiographic abnormalities, and minimal fundus changes a diagnosis of Leber's optic neuropathy was made on the basis of magnetic resonance imaging findings and the mitochondrial DNA mutation at base pair 11778.

DNA, Mitochondrial↗
PubMed1990

Ocular autonomic nerve function in Lambert-Eaton myasthenic syndrome.

Autonomic innervation to the eye and ocular adnexae was assessed in seven patients with Lambert-Eaton Myasthenic Syndrome and 50 age-matched control subjects. Pupil responses to light were abnormal in 69% of LEMS patients, compared with 18% of the control group. Reflex tear production--a screening test for parasympathetic innervation to the lacrimal gland--was below the accepted normal limit in 69% of LEMS patients. Parasympathetic and sympathetic denervation hypersensitivity of the iris musculature were individually present in 57% of LEMS patients, compared with 6% of control subjects. The association between autonomic dysfunction and Lambert-Eaton Myasthenic Syndrome is discussed.

Adult↗
PubMed1990

Leber's hereditary optic neuropathy in women.

Four women, from three families, are presented who developed severe bilateral optic nerve disease. A diagnosis of Leber's hereditary optic neuropathy (LHON) was made when male family members became affected. The disease ran a similar course in men and women with severe and permanent reduction in vision. Two women had been told that they suffered from multiple sclerosis. With recent advances in diagnostic techniques it should be possible to distinguish between these two conditions. Although LHON may be underdiagnosed in women, there does seem to be a male preponderance of the disease in most European pedigrees. Recent work supports the assumption that LHON is transmitted via cytoplasmic DNA; however, this does not explain why men are more likely to be affected, nor why only a minority of those carrying the defect develop the disease.

Adolescent↗