Biomedical subjects

T Kirkham

Publications and source records attributed to T Kirkham.

5 recordsLinked to original sources

PubMed1998

Pedigree analysis of French Canadian families with T14484C Leber's hereditary optic neuropathy.

We analyzed the clinical phenotype and determined the recurrence risks to relatives of patients with T14484C Leber's hereditary optic neuropathy (LHON). LHON is a maternally inherited optic neuropathy that primarily affects adolescent males. It is usually associated with one of three mtDNA mutations: G3460A, G11778A, or T14484C. Definition of recurrence risks for the T14484C mutation previously has not been possible due to the relative scarcity of families with this mutation. We obtained blood samples from index patients and their consenting family members, all of whom were of French Canadian ancestry and screened for LHON mutations in mtDNA. Referring ophthalmologists furnished clinical summaries and patients provided pedigree data. T14484C was the most common mutation in the pedigrees analyzed and was always homoplasmic. In these pedigrees, the ratio of affected males to females was 8:1. Median age at onset for males was 19 years (95th percentile, 40.8 years; range, 6 to 48 years). Some improvement of vision was observed in 58% of patients. Recurrence risks to brothers were 28%, sisters 5%, nephews 30%, nieces 3%, male matrilineal first cousins 19%, and female matrilineal first cousins 4%. Recurrence risks to brothers and nephews were not different; however, recurrence risks to brothers and male cousins and to nephews and male cousins were significantly different. There were no differences in recurrence risks to sisters and nieces or to either group compared with their female cousins. Affected females did not have more affected children than unaffected females. The clinical characteristics of French Canadian patients with T14484C LHON were strikingly similar to those in previous reports, suggesting that recurrence risks are generalizable to other T14484C LHON populations for genetic counseling of T14484C LHON families.

Adolescent↗

PubMed1993

Abducens palsy following shunting for hydrocephalus.

Over a period of 12 years, 80 patients underwent ventricular shunting for normal pressure hydrocephalus. Three developed sixth cranial nerve palsy in the first two weeks after surgery. This uncommon complication is usually transitory following the same pattern of abducens palsy after lumbar puncture or spinal anesthesia. Traction on the nerve with local ischemia has been involved as the responsible mechanism in both instances.

Abducens Nerve↗

PubMed1987

Bilateral homonymous hemianopia with sparing of central vision after subdural hematoma.

A patient with bilateral homonymous hemianopia with preservation of the central vision, spatial disorientation and memory deficits secondary to bilateral occipital and mesial temporal infarctions, is presented. The cerebral damage followed a subdural hematoma with tentorial herniation and compression of both posterior cerebral arteries.

Adult↗

PubMed1980

An autosomal dominant syndrome of hemiplegic migraine, nystagmus, and tremor.

A mother and son suffer from hemiplegic migraine with onset in childhood. Both have nystagmus which has not changed for many years, but the date of onset is uncertain. They have an asymmetrical tremor, clinically indistinguishable from essential tremor. Neuroophthalmological examination revealed inability to produce smooth pursuit, gaze-paretic nystagmus, rebound nystagmus, failure of fixation suppression of the vestibuloocular reflex both horizontally and vertically, and low gain of the optokinetic system. These abnormalities, confirmed by electrooculography, are commonly seen in disease of the cerebellum and brainstem. Treatment with propranolol and pizotyline lessened the number of episodes of hemiplegia and improved the tremor. Hemiplegic migraine has been reported in association with nystagmus, retinal degeneration, deafness, and ataxia in varying combinations in three other families with autosomal dominant inheritance. These associated neurological manifestations likely represent system degenerations rather than the effect of repeated ischemia imputable to the migraine itself. The syndrome of hemiplegic migraine, tremor, and ocular smooth pursuit system disorder seen in this family appears to be inherited as a single autosomal dominant trait, although more than one autosomal dominant gene may be involved.

Adolescent↗

PubMed1979

Primary aberrant third nerve regeneration.

The clinical and neuroradiological features in 4 patients with the syndrome of aberrant regeneration of the third nerve are presented. In contrast to what is commonly seen, the syndrome was not preceded by third nerve palsy. A petrous apex-cavernous sinus meningioma was the underlying lesion in all 4 patients. Surgical and pathological confirmation of the diagnosis was obtained in 3. Regardless of whether the other ocular motor nerves are spared (as in our patients) or involved (as in other cases reported in the literature), primary aberrant regeneration of the oculomotor nerve appears to be characteristic of a cavernous sinus meningioma.

Adult↗