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Show NEURO- OPHTHALMOLOGY AT LARGE The 6th European Neuro- Ophthalmological Society ( EUNOS) Meeting, Goteborg, Sweden, June 15- 18, 2003 The 6th European Neuro- Ophthalmological Society ( EUNOS) meeting was held from June 15 through June 18 in Goteborg, Sweden. The meeting drew 195 attendees from 27 countries. Its organizer, Bertil Lindblom, put together an eclectic program comprised of 51 papers, 37 posters, and 12 invited lectures. The entire set of abstracts for the meeting is published in Neuro- ophthalmology 2003; 27: 193- 262. A preliminary half- day session on the first morning was devoted to courses on ocular motility, the pupil, pseudotumor cerebri, and optic neuropathies. The afternoon session consisted of the Ahrnberg Lectures, including one on retinal neurobiology given by Berndt Ehinger ( Lund, Sweden), one on neuronal generation from stem cells in the adult brain given by Jonas Frisen ( Stockholm, Sweden), the son of Lars Frisen ( Goteborg, Sweden), and one on the potential use of stem cells for repair in neurodegenerative disease, given by Peter Eriksson ( Goteborg, Sweden). The remaining days consisted of nine sessions commencing with an invited orientational lecture and followed by free papers relating to the topic and a poster session. Here are some of the highlights ( Fig. 1). RETINAL NERVE FIBER LAYER William F. Hoyt, MD ( San Francisco, CA) gave a comprehensive historical review of retinal nerve fiber layer observations in neuro- ophthalmological diagnosis. Many fellows in the audience recognized seminal pictures from their days in training with Dr. Hoyt. Randy Kardon, MD, PhD ( Iowa City, IA) discussed the relationship between retinal nerve fiber loss, relative afferent pupillary defect, and visual field loss in optic neuropathies. Eeva Nikoskel-ainen ( Helsinki, Finland) presented studies on OPA1 gene mutations in Finnish families with dominant optic atrophy. This gene on chromosome 3q28 encodes for a GTPase protein related to dynamins. No mutational hot spot has been found and over 60 mutations of this gene have been identified. As such, simple DNA testing can be offered only for families in which the DNA mutation is known. Catherine Vignal- Clermont ( Paris, France) discussed different mechanisms of dysthyroid optic neuropathy, including apical compression of the optic nerve by enlarged muscles and orbital fat, optic nerve ischemia, lymphatic and venous stasis, and stretching of the optic nerve. Silvia Munoz ( Barcelona, Spain) presented a patient with radiation optic neuropathy who benefited from hyperbaric oxygen therapy 14 weeks after the onset of visual loss. Robert de Keizer ( Leiden, Belgium) presented four patients who experienced progressive visual impairment after total extirpation of a meningioma in the sphenoid region despite a negative MRI. All four cases experienced visual improvement after surgery disclosed tumor confined to the optic canal. Natalia Serova ( Moscow, Russia) examined the natural history of surgical hypophysectomy in 154 patients with pituitary adenoma and found that 81 % had visual improvement, 10.8% had no change, and 7.2% had visual loss. Postoperative visual loss was attributed to surgical injury to the visual pathways and their vessels, hematoma, delayed collapse of the tumor capsule, and development of an empty sella. RETINAL VASCULOPATHIES In a session dedicated to retinal vascular disorders, Dieter Schmidt ( Freiburg, Germany) discussed the pathophysiology of central retinal artery occlusion and the potential role of intra- arterial thrombolysis in the management of this dire condition. He also showed examples of an ultrasonographic halo within the temporal artery in patients with giant cell arteritis. Although he believed that this ultrasonographic finding obviates the need for temporal artery biopsy, some patients can still have disease when the sign is absent. Eberhart Zrenner ( Tuebingen, Germany) discussed the molecular mechanism in the complete form of x- linked congenital stationary night blindness, which is caused by mutations in a leucine- rich repeat protein of the NYX protein. S Gedik ( Ankara, Turkey) reviewed the use of fluorescein angiography and indocyanine green angiography in showing optic disc hyperfluorescence as the first sign of ocular Behcet's disease. Gordon Plant ( London, England) reviewed non- embolic causes of transient monocular blindness, concluding that the general absence of headache and response to nifedipine implicates vasospasm. Klara Landau ( Zurich, Switzerland) reported the outcomes following fractionated stereotactic conformal radiotherapy in eight eyes with optic nerve sheath meningioma. Controls consisted of six untreated eyes. Patients and controls had a mean follow- up of 52 months. Visual acuity or visual fields Copyright © Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited. J Neuro- Ophthalmol, Vol. 23, No. 4, 2003 301 JNeuro- Ophthalmol, Vol. 23, No. 4, 2003 Brodsky FIGURE 1. Some of the notables at the EUNOS meeting 2003. From the left: Lars Frisen ( Goteborg, Sweden); Bertil Lindblom, president of the meeting ( Goteborg, Sweden); Natalya Serova, organizer of the 2005 EUNOS meeting in Moscow, Russia; Alfred Huber ( Zurich, Switzerland), one of the founders of EUNOS; and William F. Hoyt ( San Francisco, CA). improved in six treated eyes; these parameters remained stable in four eyes and worsened in two eyes in the control group, suggesting a short term benefit of treatment. In a study of nutritional optic neuropathy in a United Kingdom cohort, Gordon Plant found that this problem arose in patients of Caribbean descent who followed a vegetarian diet and in Caucasians with alcohol abuse. Kumudini Sharma ( Lucknow, India) presented two patients who experienced delayed epistaxis and unilateral visual loss following traffic accidents. The first case developed a central retinal occlusion; the second case lost all vision and developed an afferent pupillary defect with no retinal abnormalities. In both cases, carotid angiography disclosed traumatic pseudoan-eurysms of the carotid artery ( intracavemous in the first case and projecting into the sphenoid sinus in the second). Dr. Sharma advised that patients with epistaxis and unilateral visual loss should undergo carotid angiography to diagnose carotid pseudoaneurysm, and that the optic neuropathy can result from either compression or ischemia. OCULAR MOTILITY Huibert Simonsz ( Rotterdam, The Netherlands) presented an historical review of pulley bands dating back to the earliest description by Tenon in 1805. Dr. Simonsz called into question the role of pulley attachments to the orbital wall ( which are stiff and inelastic) and suggested that intermuscular membranes and orbital fat may be more important for stabilization of ocular rotations. Nagini Sar-vananthan ( Leicester, England) presented a prevalence study of nystagmus in Leicestershire estimated to be 0.2 per 1,000. M. Castany ( Barcelona, Spain) presented a patient with suprasellar craniopharyngioma treated with yttrium- 90 brachytherapy. The patient developed a dorsal midbrain syndrome secondary to yttrium seeding of the fourth ventricle. Tony Pansell ( Stockholm, Sweden) presented video-oculography data showing that during prolonged head tilt patients show a gradual drift of the static counter roll toward zero over approximately ten minutes. Frank Proudlock ( Leicester, England) combined horizontal eye- head recordings to show that head movement gain during gaze shifts significantly increases with age. Shlomo Dotan ( Jerusalem, Israel) described four patients with pseudoglaucomat-ous cupping secondary to intracranial tumors. Helmut Tegetmeyer ( Leipzig, Germany) used video- recordings of eye movements in healthy volunteers to show the strong influence of visual perception on spatial coding of saccadic eye movements and fixation. Caroline Tilikete ( Lyon, France) found that patients with saccadic lateropulsion systematically directed their saccades toward a common " virtual target." Saccades were observed to be hypometric relative to this virtual target, suggesting that mislocalization of the target was due to perceptive error in patients with Wallenberg syndrome ( Figs. 2,3). VISUAL FIELDS Michael Wall, MD ( Iowa City, IA) gave an excellent review of currently used perimeters. He examined the relative roles of different perimetric methods for diagnosing and following different diseases, and discussed new strategies to increase sensitivity and reduce variability. Jayne Best ( London, England) presented controversial evidence that visual field defects secondary to vigabatrin are idiosyncratic and do not progress despite continuing use of the medication. Because of the short follow- up, however, these findings may simply reflect the relative insensitivity of perimetry to small degrees of progression. Hans Fledelius ( Copenhagen, Denmark) showed that patients with chiasmal lesions are often unable to read the visual acuity chart Copyright © Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited. 302 © 2003 Lippincott Williams & Wilkins Neuro- Ophthalmology at Large JNeuro- Ophthalmol, Vol. 23, No. 4, 2003 FIGURE 3. Paul Riordan- Eva ( London, UK) and Guntram Kommerell ( Freiburg, Germany) enjoying an excursion to the island of Marstrand monocularly despite little or no perimetric defect, suggesting that chiasmal lesions produce some degree of visual hemineglect. He suggested that neuroimaging be considered in patients who exhibit this monocular letter reading deficit in the temporal visual field. Simon Hickman ( London, England) presented two cases with junctional scotomas that showed MRI gadolinium enhancement of the posterior intracranial optic nerve, suggesting that the notion of Wilbrand's knee still has clinical application. Anthony Arnold, MD ( Los Angeles, CA) described seven patients who had inferotemporal arcuate field defects associated with focal superior segmental optic hypoplasia. Only one case was associated with maternal diabetes. Ulrich Schiefer ( Tuebin-gen, Germany) analyzed junctional scotomas in patients with chiasmal lesions with respect to their neurodevelop-mental underpinnings. Helmut Wilhelm ( Tuebingen, Germany) discussed the value of binocular perimetry in distinguishing organic from non organic hemifield defects. COLOR VISION Gordon Plant reviewed historical aspects of color vision as applied to current neuro- ophthalmologic diagnosis. Pinar Aydin ( Ankara, Turkey) found that during occlusion treatment of amblyopia, visual acuity shows a faster improvement than color rivalry suppression, and concluded that color rivalry suppression should be used in deciding when to stop occlusion treatment. John Barbur ( London, England) found that a new motion- based color vision test detects abnormalities in those who show no deficit on other color vision tests and have only minimal deficiency on the Nagel anomaloscope. PUPILS FionBremmer ( London, England) found that patients with generalized autonomic neuropathy have a pupillotonia that is symmetrical, with relatively preserved light reflexes and, in some cases, absence of light- near dissociation. These findings differ from the pupillotonia of the Holmes- Adie syndrome. Barbara Wilhelm ( Tuebingen, Germany) presented the Pupillographic Sleepiness Test as an objective test of daytime sleepiness and suggested its potential application in evaluating sleep disorders, driver sleepiness, drug effects, hangovers, and in other chronobiologic studies. MAGNETIC RESONANCE IMAGING Sofia Eriksson ( Goteborg, Sweden) discussed new investigational studies using diffusion tractography to depict white matter signal abnormalities within the brain, showing its application in planning surgical resection of intracranial tumors and evaluating cortical heterotopias. Catherine Bennett ( Leicester, England) examined functional MRI in patients confronted with a " filling in" stimulus. They demonstrated a cortical region of activation consistent with the presentation of a central stimulus, supporting the theory that " filling in" is an active process. Natalia Eliseeva ( Moscow, Russia) used high resolution coronal MR imaging to examine the optic nerve and subarachnoid space diameter in patients with papilledema. They found that papilledema was associated with a wider mean diameter of the subarachnoid space. More interestingly, they also found that the size of the optic nerve was increased in patients with moderate degrees of papilledema and decreased in severe or atrophic papilledema. Simon Hickman detected enhancement of the optic nerve in 27 of 28 patients with acute optic neuritis using serial gadolinium- enhanced, fat- saturated, Tl- weighted spin echo MRI images. The median duration of enhancement was 63 days. Detlef Kompf ( Liibeck, Germany) used functional MRI to demonstrate a distinct representation of visually- guided eye and hand movements in the human posterior parietal cortex. The cortex lateral to the intraparietal sulcus predominantly controls saccadic movements, while the cortex medial to the intraparietal sulcus predominantly controls visually- guided reaching movements. Irene Notting ( Leiden, The Netherlands) analyzed four cases of suprasellar germinoma and stated that diagnostic biopsy is warranted when a chiasmal mass resembling a glioma is associated with diabetes insipidus or other endocrinologic abnormalities and rapid visual decline ( Figs. 4,5). MULTIPLE SCLEROSIS Mats Sandstrom ( Stockholm, Sweden) reviewed the natural history of multiple sclerosis and argued for early Copyright © Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited. 303 JNeuro- Ophthalmol, Vol. 23, No. 4, 2003 Brodsky and aggressive treatment in light of recent findings that de-myelination is ongoing between clinical attacks. John Bar-bur investigated the recovery of visual and pupillary function in demyelinating optic neuritis and multiple sclerosis. He confirmed that afferent pupillary defects often remained despite significant improvement in vision, and that patients with recurrent demyelinating attacks showed a greater deficit in the " pupil color response" compared with the pupillary light reflex. INTRACRANIAL DISORDERS Mark Kupersmith, MD ( New York, NY) provided an excellent overview of intracranial dural arteriovenous malformations, detailing current theories of pathogenesis, clinical presentation, pathophysiology, and management. Elizabeth Graham ( London, England) described clinical findings, treatment, and prognosis of neuro- Behget's disease based on her extensive series of 23 patients from The FIGURE 5. Gordon Plant ( London, UK) and Randy Kardon ( Iowa City, IA) engaged in a lively discussion. National Hospital. All patients had anterior segment inflammation. Optic atrophy was present in 12 patients, usually due to recurrent vascular occlusion. Sixteen of 18 patients with retinal vein occlusion developed permanent neurologic deficits, in contrast to none of four patients with isolated retinal infiltrates. Irene Gottlob ( Leicester, England) used video- oculography to show that patients with schizophrenia have an abnormally high number of saccades and smaller saccadic amplitudes when reading. Discussants raised the question of whether these results could be cognitive in origin since other saccades are normal ( although an-tisaccades are abnormal). Kristina Stenberg ( Goteborg, Sweden) described a patient who developed a combination of bilateral posterior ischemic optic neuropathy and bilateral internuclear ophthalmoplegia following lower spine surgery with spinal fusion. Mark Kupersmith described the natural history of idiopathic hypertrophic meningitis in 11 patients followed for a mean of 2.3 years. He pointed out that these patients are initially corticosteroid- responsive but that immunosuppressive agents are often necessary because FIGURE 6. EUNOS 2003 Guest of Honor Alfred Huber. Copyright © Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited. 304 © 2003 Lippincott Williams & Wilkins Neuro- Ophthalmology at Large JNeuro- Ophthalmol, Vol. 23, No. 4, 2003 clinical manifestations can often recur when corticosteroids are tapered. PEDIATRIC NEURO- OPHTHALMOLOGY Michael Brodsky ( Little Rock, AR) reviewed neurologic mechanisms of congenital strabismus and proposed in this condition the eyes revert to their ancestral function as physiologic vestibules which alter central vestibular tone in any of three planes. Helmut Wilhelm examined 37 patients with amblyopia and confirmed the existence of an afferent pupillary defect of up to 0.6 log units in the absence of organic disease. Michael Brodsky presented two patients who had infantile facial hemangioma and ipsilateral peripapillary excavation ( morning glory disc anomaly in one case and peripapillary staphyloma in the other). In both cases, MR angiography showed ipsilateral carotid dysgenesis, suggesting that this association, which is found only in girls, falls within the PHACE syndrome ( posterior fossa abnormalities, hemangioma, arterial anomalies, cardiac abnormalities, and eye anomalies). Lene Martin ( Stockholm, Sweden) used Rarebit perimetry to document impaired visual function in 25 subjects who had intrauterine growth restriction. Although frequency doubling perimetry, visual acuity, and color vision were normal, eight patients had impaired visual function when tested with Rarebit perimetry, and also showed a reduced neuroretinal rim- to- disc ratio. Barbara Wilhelm presented evidence that children with attention deficit hyperactivity disorder may suffer from daytime sleepiness as measured by pupiUography. In a patient with congenital sensory nystagmus from corneal dystrophy, I. Choudhuri ( Leicester, England) found that gabapentin 2400 mg/ d improved visual acuity from 20/ 80 to 20/ 40 and reduced nystagmus intensity as measured by infrared videography ( Fig. 6). Michael C. Brodsky, MD Department of Oph University of Ark Little Rock, Arkansas Copyright © Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited. 305 |
