B W Ongerboer de Visser’s research while affiliated with Slotervaartziekenhuis and other places

Five cases of a tumour in the quadrigeminal area have been described, 4 of which could be verified by autopsy. In 2 cases with a metastasis in the tegmentum of the mesencephalon, a Parinaud syndrome was present. In 2 other cases, however, with extensive destruction of the quadrigeminal plate and of the posterior commissure this syndrome was not present. In the 5th case, with a big vascular tumour of the pineal area, disturbances of eye movements and pupils were also lacking. From these observations we may conclude that (1) destruction of the quadrigeminal plate has no influence upon vertical eye movements. (2) destruction of the posterior commissure, in combination with the quadrigeminal plate, is not always followed by disturbances of vertical eye movements. In man it is still not clear which structures are responsible for the performance of vertical eye movements.

The available clinical and pathological data of 5 cases with solitary midbrain metastasis including 2 of the present study are reviewed. Progressive dementia occurred in one case and mild dementia in another who also developed ocular symptoms. Ocular symptoms with sensory and coordination disturbances were seen in one, and only ocular symptoms in another case. Right-sided hemiplegia of 5 years duration occurred in the remaining case. Survival in tegmentum lesions is short.

The corneal reflex was studied in 21 patients with vascular lesions of the brain. Lesions localized in the frontal and temporal lobes do not affect the corneal reflex. Six patients with lesions localized behind the central sulcus and in the lower two-thirds of the parietal lobe had an abnormal direct and consensual corneal reflex following stimulation of the cornea on the side opposite to the lesion; in one of these patients the lesion was localized in the lower third of the post-central region. It can be concluded from the present study and earlier findings that the lower part of the post-central region in the parietal lobe exerts an excitatory effect on the corneal reflex. The central reflex pathways for the corneal reflex pass through the lower part of the brain stem.

A description is given of three patients with osteolytic foci in the thoracic vertebrae in whom the sensation of an electric discharge spreading down the back to both legs (Lhermitte's sign) could be elicited. These observations prove that Lhermitte's sign does not occur exclusively, as assumed until recently, in cases of lesions in or immediately adjacent to the cervical cord.

In 9 patients with Wallenberg's lateral medullary syndrome, one patient with a midbrain lesion involving the right side of the tegmentum, and 2 patients with a thalamic lesion, corneal reflexes were investigated by a new electromyographic technique. The electrophysical results were compared with the results obtained by clinical observation. In the lateral medullary lesions the electrophysiologically obtained reflex responses showed four types of abnormality. Type A consisted of a bilateral delay and type B a bilateral absence of the corneal reflex response to stimulation on the affected side in combination with a normal reflex response on both sides when the cornea on the normal side was stimulated. Type C, which was present in one case, and type D which was seen in 3 cases, consisted of a bilateral absence of the corneal reflex upon stimulation on the affected side; stimulation on the unaffected side produced a normal reflex response on the intact side in combination with, respectively, a delay or absence of the corneal reflex response on the affected side. Comparison of the clinical observations with the electrophysiological findings revealed minor discrepancies in type A and B abnormalities. However, the electrophysiological type C and D abnormalities were not detected by clinical observation. These findings demonstrate that electrophysiological recording of the corneal reflex may reveal clinically undetectable abnormalities. From the electrophysiological findings it is concluded that the corneal reflex is conducted along medullary pathways running both ipsilaterally and contralaterally from the stimulated side before connecting, respectively, with the ipsilateral and contralateral facial nucleus. From the anatomical findings it is suggested that the ascending pathways from the spinal fifth nerve complex to the facial nuclei are located in the lateral reticular formation of the lower brain-stem. The normal corneal reflex responses in the presence of thalamic and midbrain lesions involving nociceptive fibres in the trigeminothalamic tract do not support a previously postulated long-loop reflex arc passing through this tract. The suprabulbar influence upon the corneal reflex is discussed.

Three patients with 'pure motor hemiplegia' are described. This clinical syndrome may be defined as a hemiplegia or hemiparesis without sensory disorders, visual field defects or aphasia. Computer tomography revealed a lesion situated in the posterior part of the posterior limb of the internal capsule. Clinical and anatomical findings support the view that the human pyramidal tract is situated farther posteriorly in the internal capsule than used to be believed.