Significance of upward gaze palsy (Parinaud's syndrome) in hydrocephalus due to shunt malfunction

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1 Significance of upward gaze palsy (Parinaud's syndrome) in hydrocephalus due to shunt malfunction RONALD F. SHALLAT, M.D., RONALD P. PAWL, M.D., AND MICHAEL J. JERVA, M.D. Department of Neurosurgery, University o1 Illinois at the Medical Center, Abraham Lincoln School o/medicine, Chicago, Illinois Several cases are presented in which Parinaud's syndrome or upward gaze palsies were associated with hydrocephalus due to non-neoplastic aqueductal occlusion. In some of these cases the ocular signs proved to be an early and reliable indicator of increased intraventricular pressure due to shunt malfunction. The possible mechanisms by which this phenomenon occurs are discussed. The importance of differentiating such cases from those of neoplastic origin and the value of third ventriculography are stressed. KEY WoaDs upward gaze palsy hydrocephalus aqueduetal stenosis third ventrieulography Parinaud's syndrome shunt malfunction p ARINAUD'S syndrome is usually defined as a paralysis of voluntary conjugate vertical eye movements, with or without pupillary abnormalities. TM The causative lesion is thought to involve the hypothetical supranuclear vertical gaze centers in the tectal or pretectal region of the meseneepha- Ion. Although this syndrome has been described with vascular occlusive lesions, 14 it has been considered in the neurosurgical literature as being virtually pathognomonic of a mass lesion in the region of the pineal body or posterior third ventricle. 5a~ A few isolated reports have appeared, primarily in the radiological literature, which indicate that this syndrome can occur with other than neoplastic causes of hydrocephalus, particularly aqueductal stenosis?,4,6,s The following case reports are presented to emphasize this point, and in addition to stress that vertical gaze palsies can be an early and reliable sign of shunt malfunction. Case 1 Case Reports A 3 89 girl was discovered to have aqueductal stenosis associated with a myelomeningocele. The latter was repaired and a ventriculoperitoneal shunt inserted. She did well until 3 years later when the shunt failed. At this time she was noted to have widely dilated pupils with sluggish reaction to light and paralysis of upward gaze. The ocular signs improved when the shunt was revised. Ten days after discharge, she was again discovered to be unable to gaze upward, but frequent pumping of the 1. Neurosurg. / Volume 38 / June,

2 Ronald F. Shallat, Ronald P. Pawl and Michael J. Jerva shunt brought immediate and prolonged improvement. About 1 year later, the palsy of upward gaze reappeared, but this time increasing the frequency of valve manipulation failed, and the shunt was revised with complete recovery. Since that time, she has had numerous episodes of upward gaze palsy all of which have resolved with an increase in the frequency of pumping the shunt. Case 2 An l 1-year-old boy was examined because of a 2-month history of headaches and vomiting. Significant neurological findings included lethargy, ataxia, and paralysis of upward gaze. Angiography revealed marked symmetrical hydrocephalus, and a ventriculoatrial shunt was inserted. A subsequent pneumoencephalogram showed the fourth ventricle to be normal, but air failed to pass beyond the middle aqueduct. Pantopaque ventriculography, performed to rule out a posterior third ventricle mass, demonstrated the upper end of an aqueductal occlusion, and no mass in the region of the pineal or third ventricle; in fact, the suprapineal recess was distended. No further treatment was undertaken, and the patient has remained well over the past 4 years. The Parinaud syndrome cleared several months after discharge and has not recurred. Case 3 An 11-year-old boy was seen because of a 4-month history of headaches and visual difficulty. Initial examination revealed ataxia, papilledema, bilateral Babinski signs, and a right homonymous visual field defect. Angiography demonstrated hydrocephalus, and a ventriculopleural shunt was inserted. Subsequent pneumoencephalography failed to fill the axial ventricular system above the fourth ventricle, but the pericallosal cistern was noted to be dilated. He was discharged with a tentative diagnosis of aqueductal stenosis, and did well for about 1 month. At that time he developed an upward gaze palsy; the reaction to the shunt valve pumping was consistent with the diagnosis of ventricular catheter occlusion. Air and Pantopaque ventriculography at this time revealed a dilated suprapineal recess ~and Fro. 1. Pantopaque ventriculogram showing greatly enlarged suprapineal recess in Case 3 (left arrow), and occluded aqueduct (right arrow). aqueductal obstruction (Fig. 1 ). A tentative diagnosis of pineal or tectal tumor was made, and he received radiation therapy (5500 rads) over a 6-week period. Parinaud's syndrome disappeared 8 days after the onset of therapy. He was able to return to school, but 1 year later was brought back because of headache, vomiting, and a return of upward gaze palsy. The shunt was again observed to be malfunctioning when pumped and was revised; this produced complete recovery of ocular motility. Two weeks later the Parinaud syndrome recurred but abated with an increased frequency of pumping the shunt. This same sequence of events has occurred on two subsequent occasions, and in each instance rapid resolution of the gaze palsy occurred when shunt function was restored. Now, 4 years after the onset of his illness, he is well and free from neurological deficit despite repeated episodes of upward gaze paralysis relieved by ventricular decompression through pumping of the shunt. Case 4 At the age of 8 years, this 20-year-old man had had a subtotal removal of a posterior fossa medulloblastoma (Fig. 2), followed by a Torkildsen shunt and radiation therapy (3080 rads to the posterior fossa 7"18 J. Neurosur R. / Volume 38 / June. 1973

3 Parinaud's syndrome, hydrocephalus, and shunt malfunction Discussion Ft~. 2. Highly cellular neoplasm with pseudoand true rosettes. The cells have scanty cytoplasm with tapering processes and large nuclei containing coarse chromatin. Mitotic figures are numerous. H & E, X 430. and 2800 rads to the spine). Except for psychomotor retardation, he has done well until the age of 19 when he developed headaches and lethargy. Examination revealed papilledema and horizontal and vertical nystagmus. Insertion of a ventriculopleural shunt resulted in marked improvement. He returned 3 months later with recurrent headaches and vomiting. At this time there was paralysis of all vertical eye movements and paresis of lateral gaze as well. The shunt was found to be functioning poorly; revision was followed by rapid and virtually complete recovery of ocular motility. Since that time he has had two further episodes of shunt malfunction which were heralded by vertical gaze palsies. In each instance, the gaze palsies improved shortly after restoration of shunt function. Clinical and radiological evaluation has failed to reveal any evidence of tumor recurrence 12 years after the diagnosis was made. In analyzing the mechanism by which Parinaud's syndrome was produced in these cases, certain anatomical relationships must be considered. Paralysis of upward gaze is said to be produced by a rostral midbrain tectal lesion, and paralysis of downward gaze or convergence by more caudal lesions. When associated with abnormalities of pupillary reaction, the lesion is said to involve the region of the pretectal nuclei or posterior commissure. 14 The area of the mesencephalon involved is bounded by the quadrigeminal plate cistern above, by the pineal body in front, by the anterosuperior cerebellum behind, and by the aqueduct of Sylvius below (Fig. 3). In obstructive hydrocephalus, the suprapineal recess of the third ventricle may become markedly dilated and fill the quadrigeminal cistern. Further expansion may cause the recess to curve superiorly around the splenium of the corpus callosum or pass through the tentorial hiatus below and behind (Fig. 4). If the latter occurs, the dilated recess becomes interposed between the rigid tentorium and the midbrain roof, thus compressing the tectum from above, Further compression from below is caused by the expanded upper aqueduct. Another mechanism might explain the extreme shunt dependency noted in these cases. When aqueductal stenosis is present, there is frequently radiographic evidence of downward displacement of brain stem structures/,3 Before this occurs, however, the aqueduct may not be totally occluded FJc~. 3. Drawing illustrating the anatomical relationships'in the region of the rnesencephalon. 1. Neurosurg. / Volume 38 / June, ]9

4 Ronald F. Shallat, Ronald P. Pawl and Michael J. Jerva FiG. 4. Drawing showing aqueductal occlusion with expansion of the suprapineal recess and upper aqueduct resulting in tectal compression. and may even show forking, TM although sufficiently narrowed to cause ventricular enlargement above. The obstruction becomes anatomically complete, however, with compression of the aqueduct by the enlarged suprapineal recess and by the displacement and distortion of the brain stem. Additional obstruction of the CSF pathways occurs when the basal cisterns are obliterated. Shunting breaks this vicious cycle directly by decompressing the lateral ventricles and indirectly by allowing the changes to regress and the aqueduct to function, at least partially, and the basal cisterns to open. That the suprapineal recess should be so readily distended with aqueductal occlusion can be accounted for by the fact that it is the only part of the third ventricle not covered by neural or vascular structures. The recess is merely a diverticulum of the ependymal roof. 7 There have been cases in which the expanded and greatly thinned suprapineal recess has ruptured, thus creating a spontaneous decompression of the obstructive hydrocephalus. TM Because of the prohibitive morbidity and mortality 1~ associated with a direct surgical approach to neoplasms in the pineal region, the procedure adopted in some centers has been to give radiation therapy following a shunting procedure when a presumptive diagnosis has been made. Much reliance has been placed on Parinaud's syndrome, when associated with hydrocephalus, as a pathognomonic sign of a neoplasm compressing the tectum of the mesencephalon. ~,~~ In fact, this diagnosis was originally entertained in two of our cases, one of which actually received radiation therapy for a neoplasm almost certainly not present. The angiographic features of pineal tumors TM as well as aqueductal stenosis 2 have been well described. We feel, however, that in certain clinical situations, this differentiation is more reliably made by delineation of the posterior third ventricle and upper aqueduct, preferably by positive contrast ventriculography. In conclusion, we have tried to emphasize that vertical gaze palsies, when associated with obstructive hydrocephalus, are not pathognomonic of a neoplasm in the region of the pineal body. We urge that radiation therapy be withheld in cases in which there is not clearcut radiographic evidence, such as positive contrast third ventriculography, of a mass lesion in this area. We would also like to stress the value of these ocular signs as delicate indicators of ventricular pressure and shunt function in some cases. Acknowlegment The authors wish to express their appreciation to Robert F. Parshall, Assistant Professor, Department of Medical Illustration, for his drawings used in this manuscript. References I. Cassinari V, Pagni CA, Vitale A: Sindrome di Parinaud in corso di idrocefalo cronico iperteso: sofferenza della regione mesencefalica da dilatazione della porzione posteriore del III ventricolo? Minerva Neuroehir 7:84-88, Huang YP, Wotf BS, Antin SP, et al: Angiographic features of aqueductal stenosis. Am J Roentgen 104:90-108, Jakubowski J, Jefferson A: Axial enlargement of the 3rd ventricle, and displacement of the brain-stem in benign aqueduct stenosis, d Neurol Neurosurg Psychiat 35: , Jerva MJ, Nelson R: Parinaud's syndrome in progressive hydrocephalus. Mercy Med J 1: 19-20, Kahn EA, Lampe I, Crosby EC: Tumors of the posterior third ventricle and midbrain, in Kahn EA, Crosby EC, Schneider RC, et al: Correlative Neurosurgery. Springfield, III, Charles C Thomas, 1969, ed 2, p Lavender JP, Du Boulay GH: Aqueduct stenosis and cystic expansion of the suprapineal recess. Clin Radiol 16: , LeGros Clark WD: Central nervous system, in Brash JC: Cunningham's Text-Book of Anatomy. London/New York/Toronto, Oxford University Press, 1951, ed 9, pp Neurosurg. / Volume 38 / June, 1973

5 Parinaud's syndrome, hydrocephalus, and shunt malfunction 8. Lerner MA, Kosary IZ, Cohen BE: Parinaud's syndrome in aqueduct stenosis: its mechanism and ventriculographic features. Brit J Radiol 42: , Norman RM: Malformations of the nervous system, birth injury and diseases of early life, in Blackwood W, McMenemy WH, Meyer A, et al: Greenfield's Neuropathology. London, E Arnold, 1963, ed 2, p Poppen JL, Marino R Jr: Pinealomas and tumors of the posterior portion of the third vent,icle. J Neurosurg 28: , Russell DS: Observations on the Pathology of Hydrocephalus. London, His Majesty's Stationery Office, 1949, pp Seybold ME, Yoss RE, Hollenhorst RW, et al: Pupillary abnormalities associated with tumors of the pineal region. Neurology (Minneap) 21: , Taveras JM, Wood EH: Diagnostic Neuroradiology. Baltimore, Williams & Wilkins, Walsh FB, Hoyt WF: Clinical Neuro- Ophthalmology. Baltimore, Williams & Wilkins, 1969, ed 3, pp , 1845 Address reprint requests to: Ronald F. Shallat, M.D., East Bay Medical Group, Inc., 3000 Colby Street, Berkeley, California d. Neurosurg. / Volume 38 / June,