When is isolated inferior oblique muscle surgery an appropriate treatment for superior oblique palsy?

PURPOSE: To evaluate the efficacy of isolated inferior oblique muscle weakening in the treatment of superior oblique palsy. METHODS: Forty-seven patients with superior oblique palsy underwent either single-muscle surgery (anteriorization or recession of the inferior oblique muscle) or two-muscle surgery (anteriorization of the inferior oblique muscle combined with recession of the contralateral inferior rectus muscle according to the amount of vertical deviation). In a retrospective noncomparative study the objective surgical effect was calculated as the difference between the deviation at the day before surgery and the deviations 6 weeks and at least 1 year after surgery. Pre- and postoperative sensorimotor status and subjective outcome were evaluated. RESULTS: In patients who underwent isolated inferior oblique muscle surgery the mean preoperative vertical deviation decreased from 15+/-9 (distance)/16+/-10 (near) prism diopters (PD) (anteriorization) and 7+/-5 (distance)/9+/-8 (near) PD (recession) to 4+/-4 (distance)/4+/-6 (near) PD (anteriorization) and 2+/-2 (distance)/2+/-3 (near) PD (recession) at the 1-year follow-up. In patients who underwent two-muscle surgery the mean vertical deviation decreased from 20+/-11 (distance)/21+/-10 (near) PD preoperatively and 6+/-7 (distance)/6+/-6 (near) PD at 1-year follow-up. Subjective assessment showed excellent scores among the patients treated with single-muscle surgery and slightly lower but also favorable scores among the patients treated with combined techniques. A direct comparison of the different outcome scores was not possible because of the more difficult initial situation in patients who underwent combined surgery. CONCLUSIONS: Isolated inferior oblique muscle weakening is an effective treatment option for superior oblique palsy up to 15 PD of vertical deviation in primary position. Two-muscle surgery should be reserved for patients with larger vertical deviations.

Intermittent exotropia increasing with near fixation: a "soft" sign of neurological disease.

AIM: To examine the association of distance-near disparity with neurological disease in children with intermittent exotropia. METHODS: A retrospective analysis was performed of the medical records of all children with intermittent exotropia examined at the Arkansas Children's Hospital between 1989 and 2002. The study group consisted of children with intermittent exotropia who had a near deviation that exceeded the deviation at distance by at least 10 prism dioptres. The control group consisted of children with intermittent exotropia who had a distance deviation greater than or equal to the deviation at near. The main outcome measures were the prevalence of neurological abnormalities in the study and control groups. RESULTS: Among the 29 patients in the study group, 19 (66%) had a history of concurrent neurological abnormalities. Associated neurological conditions included developmental delay (10 patients), attention deficit disorder (four patients), cerebral palsy (four patients), history of intracranial haemorrhage (four patients), periventricular leucomalacia (three patients), seizures (two patients), cortical visual impairment (two patients), hydrocephalus (one patient), history of anoxic brain damage (one patient), history of encephalitis (one patient), and autism (one patient). Among the 37 patients in the control group, seven (19%) had a history of concurrent neurological abnormalities. The difference in the prevalence of neurological disease between the study group and the control group was significant (p = 0.0002). CONCLUSION: Intermittent exotropia increasing with near fixation is associated with neurological disease in children.

Intermittent exotropia increasing with near fixation: a "soft" sign of neurological disease.

AIM: To examine the association of distance-near disparity with neurological disease in children with intermittent exotropia. METHODS: A retrospective analysis was performed of the medical records of all children with intermittent exotropia examined at the Arkansas Children's Hospital between 1989 and 2002. The study group consisted of children with intermittent exotropia who had a near deviation that exceeded the deviation at distance by at least 10 prism dioptres. The control group consisted of children with intermittent exotropia who had a distance deviation greater than or equal to the deviation at near. The main outcome measure was the prevalence of neurological abnormalities in the study and control groups. RESULTS: Among the 29 patients in the study group, 19 (66%) had a history of concurrent neurological abnormalities. Associated neurological conditions included developmental delay (10 patients), attention deficit disorder (four patients), cerebral palsy (four patients), history of intracranial haemorrhage (four patients), periventricular leucomalacia (three patients), seizures (two patients), cortical visual impairment (two patients), hydrocephalus (one patient), history of anoxic brain damage (one patient), history of encephalitis (one patient), and autism (one patient). Among the 37 patients in the control group, seven (19%) had a history of concurrent neurological abnormalities. The difference in the prevalence of neurological disease between the study group and the control group was significant (p=0.0002). CONCLUSION: Intermittent exotropia increasing with near fixation is associated with neurological disease in children.

Lyme neuroborreliosis: a treatable cause of acute ocular motor disturbances in children.

BACKGROUND: Lyme neuroborreliosis (LNB) designates central nervous system involvement caused by the tick-borne spirochaete Borrelia burgdorferi (Bb). The present study describes a spectrum of acquired ocular motor disorders in children with LNB. METHODS: Six paediatric patients (age 3-15 years) with ocular motor symptoms as first manifestations of LNB evaluated by a paediatrician and ophthalmologist are presented. Diagnosis was based on new onset ocular motor disturbances and detection of cerebrospinal fluid (CSF) pleocytosis and intrathecal synthesis of Bb IgM and/or IgG antibodies by lumbar puncture. The children were evaluated before and after antibiotic treatment with a follow-up time of 1-7 months. Videos were obtained both pre and post treatment in four patients. RESULTS: Two children presented with acquired nystagmus, one with combined nystagmus and partial sixth nerve palsy, one with partial sixth nerve palsy, one with ptosis and one with Adie's pupil. Five of the patients presented with severe fatigue, malaise, nausea, headache and fever. Four had recognised a tick bite recently, and two developed erythema migrans. Intrathecal synthesis of IgM and/or IgG antibodies specific for Bb was positive in all children, and five showed CSF pleocytosis. Cerebral MRI or CT of the brain were normal. Treatment with intravenous or oral antibiotics produced rapid clinical improvement in five of the six children. CONCLUSIONS: LNB can present as acute ocular motor disorders in conjunction with fatigue and other clinical manifestations. In endemic areas, children with unexplained, acquired ocular motor abnormalities should be evaluated for LNB, a treatable medical condition.

Broad A bands of striated muscle in Leber's congenital amaurosis: a new congenital myopathy?

A 2-year-old boy with Leber's congenital amaurosis, hypotonia, depressed myotatic reflexes, and delayed motor development had numerous foci of broadened or smeared A bands, loss of distinct I bands, and near-normal Z lines in biopsied muscle. The thick filaments in these lesions appeared misaligned, suggesting an abnormality of the M line or of the structural protein connectin. This unique alteration represents the first described morphologic abnormality of muscle in a patient with Leber's congenital amaurosis.

Hypogonadotropic hypogonadism in mentally retarded adults with microphthalmia and clinical anophthalmia.

Five of 13 patients with microphthalmia or clinical anophthalmia studied in an institution of 650 mentally retarded adults had hypogonadotropic hypogonadism. Four males had low testosterone levels and sexual infantilism, manifesting as micropenis with small testes or cryptorchidism. One female had primary amenorrhea. All 5 patients had low gonadotropin levels, confirming a hypothalamic or pituitary basis for their hypogonadism. Thyroxin, thyroid stimulating hormone, prolactin, and A.M. cortisol were also measured and were normal. All patients with hypogonadotropic hypogonadism were chromosomally normal and had variable central nervous system defects, suggesting that they comprise a heterogeneous group of disorders. Microphthalmia or anophthalmia in a mentally retarded patient is associated with hypogonadotropic hypogonadism.

Dissociated vertical divergence: a righting reflex gone wrong.

Dissociated vertical divergence (DVD) is an ocular motor disorder characterized by a slow, upward drift of 1 eye when the other eye is fixating a target. I propose that DVD is a dorsal light reflex in which asymmetrical visual input to the 2 eyes evokes a vertical divergence movement of the eyes. This primitive visuo-vestibular reflex functions as a righting response to restore vertical orientation in lower lateral-eyed animals by equalizing binocular visual input. The dorsal light reflex is suppressed in humans but can manifest as DVD when early-onset strabismus precludes normal binocular development.

Optic nerve hypoplasia. Clinical significance of associated central nervous system abnormalities on magnetic resonance imaging.

Magnetic resonance imaging demonstrated coexistent central nervous system abnormalities in 30 of 40 patients with optic nerve hypoplasia. Based on their associated neuroradiological findings, these patients were placed into one of five categories: group 1, isolated optic nerve hypoplasia; group 2, absence of the septum pellucidum; group 3, posterior pituitary ectopia; group 4, hemispheric migration anomalies; and group 5, intrauterine/perinatal hemispheric injury. Posterior pituitary ectopia (group 3) and cerebral hemispheric abnormalities (groups 4 and 5) were found to be highly predictive of pituitary hormone deficiency and neurodevelopmental deficits, respectively. Isolated absence of the septum pellucidum (group 2) was associated with normal neurodevelopmental and endocrinologic function. Thinning or agenesis of the corpus callosum was predictive of neurodevelopmental problems only by virtue of its frequent association with cerebral hemispheric abnormalities. Magnetic resonance imaging can now be used to provide specific prognostic information regarding the likelihood of neurodevelopmental deficits and pituitary hormone deficiency in infants with optic nerve hypoplasia. The prevailing notion of septo-optic dysplasia as a distinct nosologic entity should be reconsidered.

Primary oblique muscle overaction: the brain throws a wild pitch.

BACKGROUND: Sensorimotor and orbital anatomical mechanisms have been invoked to explain primary oblique muscle overaction. METHODS: Review of primitive visuo-vestibular reflexes and neuroanatomical pathways corresponding to vestibulo-ocular reflexes, and correlation with known clinical abnormalities in patients with primary oblique muscle overaction. RESULTS: Bilateral superior oblique muscle overaction, which corresponds to a backward pitch in lateral-eyed animals, can occur when structural lesions involving the brainstem or cerebellum increase central otolithic input to the extraocular muscle subnuclei that modulate downward extraocular muscle tonus. Bilateral inferior oblique overaction, which corresponds to a forward pitch in lateral-eyed animals, may result from visual disinhibition of central vestibular pathways to the extraocular muscle subnuclei that modulate upward extraocular muscle tonus. CONCLUSIONS: Primary oblique muscle overaction recapitulates the torsional eye movements that occur in lateral-eyed animals during body movements or directional luminance shifts in the pitch plane. These primitive ocular motor reflexes become manifest in humans when early-onset strabismus or structural lesions within the posterior fossa alter central vestibular tone in the pitch plane.

Atypical retinochoroidal coloboma in patients with dysplastic optic discs and transsphenoidal encephalocele.

OBJECTIVE: To evaluate the clinical significance of V- or tongue-shaped infrapapillary retinochoroidal depigmentation in association with dysplastic optic discs. METHODS: Clinical data from all patients with V- or tongue-shaped infrapapillary retinochoroidal depigmentation and dysplastic optic discs were evaluated retrospectively. RESULTS: Five patients with this atypical colobomatous anomaly had transsphenoidal encephalocele. A sixth patient had an ectopic midline pharyngeal mass with no skull-base defect. CONCLUSION: In patients with optic disc dysplasias, the finding of this V- or tongue-shaped retinochoroidal pigmentary anomaly should prompt neuroimaging to look for transsphenoidal encephalocele.

Sudden death in septo-optic dysplasia. Report of 5 cases.

OBJECTIVES: To report our experience with sudden death in children with septo-optic dysplasia and to identify specific risk factors and suggest preventive measures to minimize mortality. METHODS: Clinical data from 5 children with septo-optic dysplasia who died suddenly and unexpectedly were evaluated retrospectively. RESULTS: All children had corticotropin deficiency, all had thermoregulatory disturbances, and 4 children had diabetes insipidus. In at least 4 children, clinical deterioration was caused by fever and dehydration from a presumed viral illness, which appeared to precipitate adrenal crisis. CONCLUSIONS: Children with septo-optic dysplasia and hypocortisolism are at risk for sudden death during febrile illness. Thermoregulatory disturbances and dehydration from diabetes insipidus may potentiate clinical deterioration. Prevention of sudden death in septo-optic dysplasia requires early recognition and treatment of these major risk factors.

Optic nerve hypoplasia. Identification by magnetic resonance imaging.

High-resolution magnetic resonance images of the intracranial optic nerves and chiasm were obtained in 15 patients with severe optic nerve hypoplasia. These were compared, in a double-blind manner, with similar images from 30 age-matched controls. On both coronal and sagittal images, hypoplastic optic nerves were thin and demonstrated signal attenuation when compared with normal optic nerves. All patients with severe bilateral optic nerve hypoplasia also had diffuse chiasmal hypoplasia, which was seen best on coronal images. Patients with unilateral or asymmetrical optic nerve hypoplasia had variable chiasmal abnormalities. The degree to which the magnetic resonance diagnosis of optic nerve hypoplasia matched the clinical diagnosis was highly significant (P less than .001, Fisher's Exact Test) for both coronal and sagittal views of the intracranial optic nerves. Oblique axial and coronal views of the orbital optic nerves did not reliably distinguish optic nerve hypoplasia from normal optic nerves. High-resolution magnetic resonance imaging is a useful diagnostic modality to identify small optic nerves neuroradiologically.

Orbital optic glioma in neurofibromatosis. Magnetic resonance diagnosis of perineural arachnoidal gliomatosis.

In a patient with neurofibromatosis and orbital optic glioma, T2-weighted axial magnetic resonance images showed a fusiform area of high signal intensity with a central linear core of lower signal intensity. Computed tomographic images did not show a corresponding variation in tumor density. Histopathologic examination of the tumor revealed dense, circumferential, perineural glial proliferation. This "arachnoidal gliomatosis" is a feature of orbital optic gliomas in neurofibromatosis and, in our magnetic resonance scans, accurately corresponded with the region of high signal intensity within the tumor.

The "pseudo-CSF" signal of orbital optic glioma on magnetic resonance imaging: a signature of neurofibromatosis.

A five-and-a-half-year-old boy with neurofibromatosis had bilateral orbital optic gliomas visible on magnetic resonance imaging. Both tumors displayed a double-intensity signal characterized by a circumferential area of CSF-intensity tissue surrounding and sharply delimited from a central linear core of opposite signal intensity. The peripheral CSF-intensity signal in orbital optic glioma correlates with the histopathological finding of perineural arachnoidal gliomatosis and serves as a neuroradiologic marker for neurofibromatosis.

Congenital optic disk anomalies.

Over the past decade, a wealth of information has accumulated pertaining to the diagnosis and management of patients with congenital optic disk anomalies. As new examples of each entity have been detailed, the diagnostic criteria for each anomaly have become more clearly defined. The advent of sophisticated noninvasive neuroimaging techniques has further refined our ability to accurately detect and categorize the associated CNS anomalies that complicate many of these conditions. In light of recent findings, this review will critically examine many of the well-entrenched concepts pertaining to the diagnosis, evaluation, and treatment of patients with congenital optic disk anomalies. In so doing, it will attempt to dispel some longstanding misconceptions that pervade the literature and obscure our understanding of the pathogenesis, neuroradiological associations, and systemic implications of each anomaly.

The case of the gray optic disc!

A child with interstitial deletion of chromosome 17, right optic nerve hypoplasia, and impaired speech had bilateral congenital optic disc pigmentation, giving the appearance of gray optic discs. This appearance did not change over a period of two-and-a-half years. Previous cases of gray optic discs in neonates have been notable for 1) absence of visible pigmentation within the optic discs, 2) resolution of the gray discoloration over a period of months, and 3) development of albinotic features in several infants. This suggests that congenital optic disc pigmentation is a rare cause of gray optic discs. Congenital optic disc pigmentation is compatible with good vision.

Blindness, deafness, quadriparesis, and a retinal malformation: the ravages of neurofibromatosis 2.

Advances in molecular biology have established that the diseases once collectively referred to as neurofibromatosis are actually genetically distinct and clinically heterogenous conditions. This realization has led to separate definitions for neurofibromatosis (NF) type 1 and 2. Although ophthalmologic manifestations of NF1 have long been recognized, the distinguishing ocular features of NF2 have only recently received attention. We describe an inferior retinopapillary malformation with an overlying glial hamartoma in a deaf, quadriparetic patient with NF2. Magnetic resonance (MR) imaging initially showed bilateral vestibular schwannomas and a large cervical ependymoma. Over six years of follow-up, the patient developed multiple intracranial meningiomas.

Bilateral iris tumors in an immunosuppressed child.

A seven-year-old iatrogenically immunosuppressed girl developed simultaneous bilateral iris tumors associated with granulomatous iridocyclitis, splenomegaly, and an immunoblastic pleocytosis. Serologic studies suggested a current active Epstein-Barr virus infection. Tumor biopsy showed a polyclonal plasmacytoid lymphoproliferative process, establishing the diagnosis of posttransplant lymphoproliferative disorder. Low-dose local irradiation produced rapid and complete iris tumor regression with restoration of vision in both eyes. To our knowledge, this is the first report of ocular involvement in posttransplant lymphoproliferative disorder.

Aicardi syndrome: more than meets the eye.

An eight-month-old girl with infantile spasms and apparent blindness had electroencephalographic findings compatible with Aicardi syndrome. In addition to optic nerve hypoplasia, there were multiple congenital retinal malformations in the right eye, including chorioretinal lacunae, anomalous retinal vessels, posterior scleral ectasia, and a peripheral fibrous ridge. Magnetic resonance imaging demonstrated agenesis of the corpus callosum, absence of the septum pellucidum, optic nerve and chiasmal hypoplasia, pachygyria, cortical heterotopias, colpocephaly, and hypoplasia of the cerebellar vermis. This patient illustrates the broad spectrum of cerebroretinal malformations now known to characterize Aicardi syndrome.

Optic nerve hypoplasia with posterior pituitary ectopia: male predominance and nonassociation with breech delivery.

PURPOSE: To determine whether posterior pituitary ectopia in children with optic nerve hypoplasia has a male predominance or an increased incidence of breech delivery. METHOD: Retrospective analysis of 12 children with optic nerve hypoplasia and posterior pituitary ectopia. RESULTS: Eleven of 12 patients with posterior pituitary ectopia were boys. No child had a history of breech delivery. Two children had a history of breech positioning but were delivered by cesarean section. CONCLUSION: Posterior pituitary ectopia with optic nerve hypoplasia shows a strong male predominance but no association with breech delivery.