Paroxysmal Tonic Upgaze: Physiopathological Considerations in Three Additional Cases

Abstract

Paroxysmal tonic upgaze of childhood has been described as a benign distinctive syndrome of abnormal ocular movement, with or without concomitant ataxia. After the first observation of four children, a further 29 patients have been reported with a wide spectrum of neurologic abnormalities such as ataxia, unsteady of gait, learning disabilities and mental retardation at follow-up. Electroencephalograms were normal in all the subjects and magnetic resonance imaging showed deficient myelination in only one patient. Recently it has been suggested that paroxysmal tonic upgaze could be a heterogeneous syndrome, ranging from a simply age-dependent manifestation to a clinical appearance of a variety of disorders affecting the corticomesencephalic loop of vertical eye movement. Moreover, it also could be an early sign of more widespread neurologic dysfunction. We describe three patients who presented paroxysmal tonic upgaze; in one, ataxia was present; in the second child, ataxia and language disorder also were observed; and in the third patient paroxysmal tonic upgaze was associated with loss of muscle tone (drop-attack-like events). On magnetic resonance imaging, a pinealoma compressing the dorsal mesencephalic region was detected. On the basis of our observations, we suggest that any insult with periaqueductal mesencephalic gray-matter involvement could be considered the basic condition for this peculiar clinical manifestation.

Abstracts

“…Rarely, retinal dysfunction can result in upward deviation of the eyes. PTU can be associated with various structural brain lesions, including white‐matter disease,100, 101 brain tumors,102 brain malformations,94 and chromosomal abnormalities resulting in severe brain dysfunction 103, 104. We consider that, even if the manifestations partly mimic those of classical “idiopathic PTU” in such patients, they should be seen as a separate entity and be referred to as symptomatic PTU, with a different course, prognosis, and management.…”

Benign paroxysmal tonic upgaze of childhood in a hypotonic infant with Beckwith–Wiedemann syndrome

“…Between episodes neurological examination, EEG, imaging and cerebrospinal fluid neurotransmitter studies are typically normal. Associations with ataxia, hypotonia, epilepsy, developmental delay, language disorders, fetal exposure to valproate, periventricular leukomalacia, vein of Galen malformation, hypomyelination and pinealoma have been reported 1,2,4 . Autosomal dominant inheritance and abnormal duplicates of chromosome 15 have been described 2,5 …”

“…The pathogenesis of PTU is unknown. It may be a transient developmentally related phenomenon, or part of widespread neurological dysfunction affecting cortico‐mesencephalic control of vertical eye movement 1,2,4 . Some authors suggest that the common abnormality is in the periaqueductal grey area 4 .…”

“…It may be a transient developmentally related phenomenon, or part of widespread neurological dysfunction affecting cortico‐mesencephalic control of vertical eye movement 1,2,4 . Some authors suggest that the common abnormality is in the periaqueductal grey area 4 . Although the ocular features of PTU generally disappear within a few years, cases not infrequently have persisting ataxia, minor oculomotor disorders and borderline cognitive abilities 1,2,4,5 …”

“…Some authors suggest that the common abnormality is in the periaqueductal grey area 4 . Although the ocular features of PTU generally disappear within a few years, cases not infrequently have persisting ataxia, minor oculomotor disorders and borderline cognitive abilities 1,2,4,5 …”