PubMed Health⌕ Search

Biomedical subjects

E Bollen

Publications and source records attributed to E Bollen.

10 recordsLinked to original sources

Saccadic eye movements in idiopathic blepharospasm.

Visually guided saccades, memory-contingent saccades, and antisaccades were studied with an infra-red reflection technique in 12 patients with idiopathic blepharospasm and in controls. Latencies of the three kinds of saccades were prolonged. Peak velocities and gains did not differ. Our results indicate an initiation defect in the saccadic system, which may be localized in the caudate nucleus.

Adult↗

Saccadic eye movements in hyperekplexia.

Hyperekplexia is an autosomal dominant disorder characterized by excessive startle responses followed by a temporary generalized stiffness. The startle response is generated in the medial bulbopontine reticular formation in the lower brainstem. The pulse generator of horizontal saccadic eye movements is localized in the pontine paramedian reticular formation. Measurements of horizontal visually evoked random saccades, antisaccades, and saccades toward remembered targets were performed in seven patients with familial hyperekplexia and seven health age-matched controls. The peak velocity of all three kinds of saccades was reduced (p < 0.0001) compared with that of controls. Latencies were marginally longer in the patient group (p = 0.0486). Saccadic gains did not differ between patients and controls. The ability to make antisaccades, saccades toward remembered targets, and the ability to suppress reflex saccades are similar in patients and controls. These data suggest that the origin of the excessive startle response is probably more due to a different modulation in the brainstem than to altered cortical influence.

Acoustic Stimulation↗

Variability of the main sequence.

PURPOSE: This study investigated the relationship between amplitude and peak velocity of saccadic eye movements (the so-called main sequence) and the intra-individual variability of the main sequence. METHODS: Saccadic amplitudes and peak velocities were measured twice in 58 healthy subjects with an infrared reflection technique. RESULTS: Considerable intra-individual variability was found between the first and second recordings. CONCLUSIONS: Intra-individual variability of saccadic peak velocity affects the interpretation of changes in repeated recordings of peak velocities, such as before and after medication is administered. Furthermore, considerable intra-individual variability decreases the probability that statistically significant differences between patients and control subjects can be detected, especially when groups are small. Calculating the intraclass correlation coefficient allows the number of subjects in comparative studies to be determined.

Adult↗

Reversible mental deterioration and neurological disturbances with o,p'-DDD therapy.

A patient with serious neurological and neuropsychological side-effects of a 2-year treatment with 1,1-dichloro-(o-chlorophenyl)-2-(p-chlorophenyl)ethane (o,p'-DDD) for adrenal carcinoma showed complete recovery after discontinuation of the drug. Studying a larger number of patients during and after long term treatment with o,p'-DDD is indicated. If results of this report are confirmed, therapy should not be discontinued even if serious side effects occur.

Adrenal Cortex Neoplasms↗

Eye movements in myotonic dystrophy.

Smooth pursuit eye movements were studied with infrared reflection equipment in 10 patients with myotonic dystrophy and in 10 age- and sex-matched controls. Smooth pursuit gain, measured after correction for catch-up saccades, was decreased in the patient group. Normal latencies of saccadic eye movements made a lack of attention an unlikely explanation for this low gain. Likewise, presence of catch-up saccades and normal fixation made it unlikely that extra-ocular myopathy explained the low smooth pursuit gain. We suggest that periventricular white matter abnormalities represent a more likely explanation.

Adult↗

Pain in scar as an early symptom of acquired thoracic lung hernia.

Hernia of the lung manifests itself as an elastic, usually replaceable, swelling in the chest wall, which changes in size during inspiration and expiration. It does not generally cause any symptoms. We describe the case history of a 49 yr old man with an acquired thoracic lung hernia, which had first presented three years previously as pain in an operation scar during coughing and lifting. Histopathology of the excised lung tissue showed abnormalities suggestive of previous episodes of strangulation.

Cicatrix↗

Trigeminal neuralgia-like pain in an aged woman with fibrous dysplasia of the skull base.

A 72 year old woman with attacks of severe lancinating pain in the right frontotemporal region of her face had, on CT scan of the skull base, fibrous dysplasia of the right sphenoid bone, involving the areas traversed by the trigeminal nerve. Her pain ceased following treatment with methysergide. In patients with hemifacial pain but no evident facial or skull deformities, CT scan of the skull base may be helpful in elucidating the diagnosis.

Aged↗

Horizontal and vertical saccadic eye movement abnormalities in Huntington's chorea.

With a newly developed infrared reflection technique, voluntary saccadic eye movements (VOLS), visually evoked saccades (VES) and unsuppressed visually evoked reflex saccades (USVERS) were measured in 11 patients with Huntington's chorea. Abnormalities, including latency increase, peak velocity decrease and undershoot dysmetria with multiple step saccades were found in all types of saccadic eye movements. Peak velocity decrease and undershoot dysmetria can be explained by dysfunction of the brainstem reticular formation in Huntington's chorea. USVERS and square wave jerks occurred abnormally frequently and showed direction-dependent differences. Both were more frequent in horizontal than in vertical direction. Frequency of USVERS and square-wave jerks tended to be correlated. These findings point to disinhibited superior colliculi as a possible common supranuclear origin of USVERS and square-wave jerks in Huntington's chorea.

Adult↗

Brainstem reflexes and brainstem auditory evoked responses in Huntington's chorea.

Blink reflex, corneal reflex, jaw reflex, exteroceptive suppression in masseter muscles and brainstem auditory evoked potentials were measured in 20 patients with Huntington's chorea and 12 controls. A significantly increased latency of the second component of the homolateral and heterolateral blink reflex was found in the patient group as compared with the controls. The other investigations revealed no significant differences between patients and controls except for some facilitation of the jaw reflex in the patient group. Increase of second component latency of the blink reflex in the presence of normal corneal reflexes is suggestive of functional impulse conduction disturbance in the lower brainstem. It is discussed whether in Huntington's chorea this is to be attributed to alterations of cortical or striatal influence or to local brainstem abnormalities.

Adult↗