Periaqueductal dysfunction (the Sylvian aqueduct syndrome): a sign of hydrocephalus?

Neuroophthalmological Symptoms in Children Treated for Internal Hydrocephalus

“…The syndrome, described in detail by Kestenbaum in 1946, has also been described and dis cussed by many authors in patients with internal hydro cephalus [10,12,15], The most probable pathogenesis of the periaqueduct syndrome is a transependymal imbibi tion with liquor of the adjacent structure and the dilata tion of the third ventricle and aqueduct of Sylvius induc ing disorders in cerebral blood flow in that region [7,10,17], The presence of a concomitant malformation can not be excluded as a possibility [18]. The occurrence of this syndrome is most often a manifestation of a sharp elevation of the ventricular pressure, particularly in dis turbed function of the shunt, which according to some authors is an indication for urgent surgical treatment [12,15,17], The occurrence of such symptoms could be explained with transitory changes in the ventricular pres sure [5,19], Papilledema is the most frequently discussed mani festation in the hydrocephalic-hypertensive syndrome, with the generally accepted opinion that its manifesta tion is adequate to the extent of the internal hydroceph alus [4], The exceptionally great clinical significance of this symptom is confirmed by the numerous attempts made at elucidating its pathogenesis on clinical and experimental material [8,11,20,21], The direct link between the state of the anterior fontanelle and the extent of the lesion on the optic nerve is underlined by a great many authors [11,14,16,22]. The pathogenetic mechanisms leading to the optic atrophy in the optic nerve are discussed in various sources of the literaturepreceding papillary edema, direct compression, isch emia, disturbed cerebral hemodynamics, and elevated pressure in the central retinal artery [21,[23][24][25].…”

Convergence and retraction nystagmus in hydrocephalus due to shunt malfunction.

“…Recently, the Sylvian aqueduct syndrome has come to be recognized as a sign of hydrocephalus or shunt malfunction (Swash, 1974;Chattha et al 1975;Osher et al 1978;Barrer et al 1980), although the etiology of the syndrome has long been thought to be a fixed, structural lesion, such as a neoplasm, cerebrovascular disease, CNS infection or demyelinating disease (Segarra et al 1961). Swash (1974) first reported a patient with aqueductal stenosis who manifested the Sylvian aqueduct syndrome during a sudden increase in intracranial pressure.…”

“…Swash (1974) first reported a patient with aqueductal stenosis who manifested the Sylvian aqueduct syndrome during a sudden increase in intracranial pressure. The ocular signs such as, upward gaze palsy, convergence nystagmus resolved when the hydrocephalus was relieved.…”

“…As to the mechanism of Sylvian aqueduct syndrome in hydrocephalus or shunt malfunction, Swash (1974) suggested that the ocular signs were the result of periaqueductal dysfunction due to assimilation and dilatation of the aqueduct with secondary tentorial block. Barrer et al (1980) suggested that dilatation of the third ventricle and rostral aqueduct was the probable mechanism of the syndrome.…”

Sylvian aqueduct syndrome as a sign of acute obstructive hydrocephalus in children.

“…) aqueductal stenosis who had paralysis of upward gaze and pupillary abnormalities. Subsequently, there have been isolated case reports of upward gaze paralysis occurring in hydrocephalus, mostly of later onset (Globus and Bergman, 1946;case 1;Beckett et al, 1950, case 8;Cassinari et al, 1963;Nag and Falconer, 1966, case 8;Lerner et al, 1969;Jerva and Nelson, 1971;Shallat et al, 1973;and Swash, 1974); however, this reported association has not found its way into the leading textbooks of neuro-ophthalmology of Kestenbaum (1946), Cogan (1956), and Walsh and Hoyt (1969) and the review articles of Holmes (1921), Smith et al, (1959), Segarra and Ojeman (1961), and Hatcher and Klintworth (1966).…”