Trochlear-oculomotor synkinesis: another congenital cranial dysinnervation disorder? / Sincinesia troclear-oculomotora: outro distúrbio congênito de denervação craniana?

ABSTRACT This report documents an unusual phenomenon. A 6-year-old girl with trochlear-oculomotor synkinesis presented with superior oblique and palpebral levator co-contraction. The literature was reviewed and the possibility of classifying this entity as a congenital cranial dysinnervation disorder was speculated.

RESUMO Este relato descreve um fenômeno incomum. Uma menina de 6 anos com sincinesia troclear-oculomotora apresentou co-contração do oblíquo superior e do levantador da pálpebra. A literatura foi revisada e especulou-se a possibilidade de classificar essa desordem como um distúrbio da congenital cranial dysinnervation disorder.

Trochlear-oculomotor synkinesis: another congenital cranial dysinnervation disorder?

This report documents an unusual phenomenon. A 6-year-old girl with trochlear-oculomotor synkinesis presented with superior oblique and palpebral levator co-contraction. The literature was reviewed and the possibility of classifying this entity as a congenital cranial dysinnervation disorder was speculated.

Congenital Oculonasal Synkinesis.

A 4-year-old girl with maxillary hypoplasia, intermittent exotropia, and high myopia displayed congenital oculonasal synkinesis. We examine the implications for pathogenesis of these disparate craniofacial findings.

Congenital third nerve palsy with synergistic depression on attempted adduction and trigemino-oculomotor synkinesis: Underpinnings of a spectral dysinnervation disorder.

The authors describe a case of congenital partial pupil-sparing third cranial nerve palsy with absent adduction, synergistic depression of globe and widening of palpebral fissure on attempted adduction and synergistic elevation and adduction on mouth opening and sideways thrusting of jaw. The case illustrates trigemino-oculomotor synkinesis associated with congenital third nerve palsy. The possible mechanism of miswiring involving the medial longitudinal fasciculus and trigeminal nuclei is discussed. At least some cases of congenital third cranial nerve palsy may fall in the realm of congenital cranial dysinnervation disorders (CCDDs) sharing a much wider spectrum of presentation.

Congenital trochlear-oculomotor synkinesis.

Synkinesis of the extraocular muscles forms a subset of congenital ocular motility abnormalities termed congenital cranial dysinnervation disorders. Synkinesis most frequently involves the abducens or oculomotor nerves and rarely the trochlear nerve. Only 3 such patients have been described in the literature. We report an isolated case of trochlear-oculomotor synkinesis in a healthy 6-year-old boy and discuss the proposed pathophysiology of this disorder.

Congenital trigemino-abducens synkinesis in a neonate.

Congenital ocular synkinesis syndromes involve aberrant innervation of extraocular and eyelid muscles in a variety of patterns. A rare iteration is trigemino-abducens synkinesis, with only three published cases to date. Here the authors report (with video documentation) the earliest documented age of trigemino-abducens synkinesis and congenital ocular synkinesis in general. A 13-week-old (40-week postmenstrual age) girl presented with rhythmic abduction of the left eye that coordinated with sucking, likely resulting from abnormal embryologic development, causing activation of the lateral rectus by motor fibers of the mandibular branch of the trigeminal nerve.

Ptotic lid elevation during contralateral head tilt.

Congenital abnormal synkinesis involving the eyelid, which is well described in the Marcus Gunn jaw-winking phenomenon, also has been reported in association with axons intended for facial musculature, extraocular muscles, and the pupil.(1,2) The subject of this report is a novel form in which the patient's ptotic eyelid elevated only during contralateral head tilt when the patient was upright, suggesting a congenital abnormality within the otolith-oculomotor pathway.

Paediatric phenotype of Kallmann syndrome due to mutations of fibroblast growth factor receptor 1 (FGFR1).

Kallmann syndrome characterised by hypogonadotropic hypogonadism (HH) and anosmia is genetically heterogeneous with X-linked, autosomal dominant and autosomal recessive forms. The autosomal dominant form due to loss of function mutation in the fibroblast growth factor receptor 1 (FGFR1) accounts for about 10% of cases. We report here three paediatric cases of Kallmann syndrome with unusual phenotype in two unrelated patients with severe ear anomalies (hypoplasia or agenesis of external ear) associated with classical features, such as cleft palate, dental agenesis, syndactylia, micropenis and cryptorchidism. We found de novo mutation in these two patients (Cys178Ser and Arg622Gly, respectively), and one inherited Arg622Gln mutation with intrafamilial variable phenotype. These genotype-phenotype correlations indicate that paediatric phenotypic expression of FGFR1 loss of function mutations is highly variable, the severity of the oro-facial malformations at birth does not predict gonadotropic function at the puberty and that de novo mutations of FGFR1 are relatively frequent.

Congenital oculomotor nerve synkinesis associated with fetal retinoid syndrome.

INTRODUCTION: Isotretinoin (RA), used for the treatment of cystic acne, is a powerful teratogen, causing craniofacial dysmorphisms and neural tube defects. We present two patients with RA embryopathy and oculomotor nerve synkinesis. METHODS: Retrospective review of patient records. RESULTS: Two patients presented with third nerve synkinesis and fetal RA exposure. Both had marked elevation of the upper eyelids on adduction such that the lid fissures alternately opened and closed on gaze from side to side. Both patients showed typical dysmorphisms of RA embryopathy. The first patient had complete agenesis of the cerebellar vermix and died at 2 years. The second patient had restricted extraocular muscles in one eye and was exotropic and hypotropic. DISCUSSION: Both patients demonstrated simultaneous innervation of the medial rectus and levator palpebrae muscles causing coincident lid elevation in adduction. This evidence of oculomotor nerve synkinesis is consistent with animal studies showing abnormalities in the formation of cranial nerve ganglia following fetal RA exposure. CONCLUSION: RA is a powerful teratogen. These patients provide additional clinical evidence of its influence on neural migration during early development.

Dominance of ipsilateral corticospinal pathway in congenital mirror movements.

OBJECTIVE: To clarify the mechanism of congenital mirror movements. DESIGN: The triple stimulation technique (TST) and the silent period were used to investigate a patient with congenital mirror movements. The TST was used to calculate the ratio of ipsilateral to contralateral corticospinal tracts from the two hemispheres to the spinal motor neurones. RESULTS: Transcranial magnetic stimulation over unilateral M1 induced larger ipsilateral than contralateral motor evoked potentials on both sides. Only 9% of spinal motor neurones innervating the abductor digitorum minimi were excited by contralateral primary motor cortex (M1) stimulation, while 94% were excited by the ipsilateral M1 stimulation. The silent period was examined during mirror movements and with voluntary contraction of the right first dorsal interosseus mimicking mirror movements. Left M1 stimulation (through the crossed corticospinal tract) did not show any difference in silent period between the two conditions, while right M1 stimulation (through the uncrossed tract) caused a longer silent period during mirror movements than during voluntary contractions. CONCLUSIONS: The results suggest that mirror movements may be caused by a strong connection between ipsilateral M1 and the mirror movements conveyed through a dominant ipsilateral corticospinal pathway.