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Show Journal of Neuro- Ophthalmology 21( 4): 311- 315, 2001. © 2001 Lippincott Williams & Wilkins, Inc., Philadelphia Neuro- Ophthalmology At Large The Fifth European Neuro- Ophthalmological Society ( EUNOS) Meeting, Tubingen, Germany, July 22- 26, 2001 Jonathan D. Trobe, MD The Fifth European Neuro- Ophthalmological Society ( EUNOS) Meeting drew more than 200 attendees from 33 countries to Tubingen, Germany, July 22 through 26, 2001. The meeting was held at the University of Tubingen, which was founded in the 14th century and is the second oldest university in Germany ( after Heidelberg). The meeting's organizers, Susanne Trauzettel- Klosinki, Helmut Wilhelm, Barbara Wilhelm, and Eber-hart Zrenner of the University's Department of Pathophysiology of Vision and Neuro- ophthalmology, put together an impressive program that included 46 papers, 50 posters, and 25 invited lectures. ( Abstracts are published in the Journal of Neuro- ophthalmology 2001, 24: 1- 102). A preliminary half- day session was a refresher course on the pupil, neuroradiology, oculomotor disorders, and the electroretinogram ( ganzfeld and multifocal). The first day concluded with a festschrift in honor of Bill Hoyt's 75th birthday, given by his former fellows. More than 25 former fellows participated, 11 of whom delivered short papers ( Mike Sanders, Anja Palmowski, Bernd Schlicke, Klara Landau, Ivor Levy, Chris Kennard, Gordon Plant, Patricia Logan, Kay- Uwe Hamann, Paul Riordan- Eva, and Guntram Kommerell). Recalling his triumphs and humiliations as one of Bill's earliest fellows, Kommerell called Hoyt the " seminal figure for neuro- ophthalmology in Europe." Thereafter, the meeting was divided into five topic sessions centered around invited lectures designed to update the audience on critical issues. From the Departments of Ophthalmology and Neurology, University of Michigan, Kellogg Eye Center, Ann Arbor, Michigan. Address correspondence to Jonathan D. Trobe, MD, Departments of Ophthalmology and Neurology, University of Michigan, Kellogg Eye Center, Ann Arbor, MI 48105. PERCEPTUAL DISORDERS OF VISION In a session devoted to perceptual aspects of vision, Hanspeter Mallot ( Tubingen) and Guy Orban ( Louvain) introduced recent experimental work on object and motion processing. Hans Otto Karnath ( Tubingen) argued that human lesion studies of unilateral neglect suggest that spatial awareness in humans is processed in the right superior temporal cortex rather than in the posterior parietal cortex, as has been assumed from monkey studies. He reasoned that the emergence of language in the left temporal cortex of humans is associated with a shift of spatial awareness from right parietal to right superior temporal cortex. Dominic Mort ( London) reported on scanpath strategies; Avinoam Safran ( Geneva) reported on plasticity in the visual cortex; Susanne Trauzettel- Klosinki ( Tubingen) reported on reading strategies, as observed with scanning laser ophthalmoscopy, in patients with various visual impairments; Francois Punting on the River Neckar in Tubingen, site of the 5th EUNOS Meeting, July 22- 26, 2001. 311 312 NEURO- OPHTHALMOLOGY AT LARGE Vital- Durand ( Lyon) updated the audience on visual development in infants; and Lea Hyvarinen ( Helsinki) reported that sessions of flicker stimulation of the blind hemifield in one patient eventually resulted in improvement in vision in that field, an argument that left several listeners unconvinced. PERIMETRY In a session dedicated to perimetry, Lars Frisen ( Gote-borg) posited that the newest technological developments in stimulus presentation are further exposing the subjective- and therefore unreliable- nature of this test. Given the sophisticated imaging tools we now have for locating structural and even functional brain impairments, he also suggested that future perimetric devices may find their greatest utility in providing a quick overall index of function rather than spatial detail. Robert Mc- Fadzean ( Glasgow) recapitulated the current views on the topographic organization of visual cortex, based on lesional studies in primates and humans, and on functional magnetic resonance imaging ( MRI). Ulrich Schiefer ( Tubingen) delivered an eloquent paean to Elf-riede Aulhorn, the former Tubingen professor who died prematurely in 1991. She largely developed the famed Tubingen Manual Perimeter and left a rich legacy of visual field data. Pinar Aydin ( Ankara) reported that high- pass perimetry provides valuable information in patients with dysthyroid optic neuropathy. Freddie Huber ( Zurich) presented a report of a patient with an episode of full- field dyschromatopsia (" everyone appeared brownish- yellow") signaling the presence of a right parietooccipital glioblastoma. Surprisingly, formal visual fields were normal. Shlomo Dotan ( Jerusalem) described cases of tamoxifen-, vigabatrin-, and sildenafil- induced visual disturbances. Eedy Mezer ( Toronto) used a sweep visual evoked potential ( VEP) test to measure contrast sensitivity objectively in children with papilledema and found that peak contrast sensitivity was slightly, but not significantly, lower in subjects in the papilledema group than in control subjects, perhaps owing to small sample size. Susanne Trauzettel- Klosinski ( Tubingen). / Neuro- Ophthalmol, Vol. 21, No. 4, 2001 Claudia and Eberhart Zrenner. ASSESSMENT OF VISUAL FUNCTION In a session dedicated to advances in methods of assessing visual function, Michael Bach ( Freiburg) proposed that newer computerized methods of measuring visual acuity, contrast sensitivity, and stereoacuity provide more accurate information. Candice Chen, a medical student at Columbia University ( New York), Helmut Wilhelm ( Tubingen), Eitan Roth ( Haifa), Shlomo Dotan ( Jerusalem), and Barbara Wilhelm ( Tubingen). NEURO- OPHTHALMOLOGY AT LARGE 313 Susanne Trauzettel- Klosinski ( Tubingen) and Guntram Kommer-ell ( Freiburg) with Bill Hoyt at the end of a symposium in honor of his contributions to neuro- ophthalmology. representing the efforts of the psychophysics/ electro-physiology group there to improve the reliability of the multifocal VEP, showed that adding recording electrodes and channels increases the ability of this method to detect optic nerve disorders. Noting that patients with impaired pursuit eye movements often complain of reduced vision, Thomas Harmeier ( Tubingen) measured dynamic visual acuity with horizontally moving Landolt C's and found a marked deficit in patients with impaired pursuit as compared with control subjects. Josephine Shallo- Hoffmann ( Fort Lauderdale) found that, in screening 102 preschool children, more could complete the Lea Symbol Visual Acuity and Lang Stereoacuity Tests than the standard Tumbling E and Randot E Tests. Freddie and Mrs. Huber at the opening reception. BRAIN IMAGING In a minisymposium on brain imaging, Rainer Goebel ( Maastricht) provided evidence that magnetoencephalog-raphy ( MEG) improves the temporal resolution of functional MRI in vision- related event mapping. Simo Vanni ( Toulouse) also showed that MEG is a useful tool in localizing cortical regions responsible for visual processing. Philippe Demaerel ( Louvain) presented MRI follow- up of 19 children with anterior visual pathway glioma and showed that in seven of eight patients who were untreated, tumor size did not increase; in 10 patients treated with vincristine and carboplatin, the tumor shrank in six and remained unchanged in one. In essence, the prognosis was excellent. Mark Kupersmith ( New York) found MRI enhancement of the affected optic nerve in 101 of 107 patients ( 95%) with optic neuritis, a number that appeared astoundingly high to others with similarly heavy caseloads. There was no correlation between the location of the enhancement ( orbit, canal, or intracranial segments) and the severity of visual loss or its outcome. Dieter Schmidt ( Freiburg) presented evidence that a dark halo around the lumen and luminal thickening on color- coded Duplex sonography are the most specific sonographic signs of temporal arteritis. Jette Frederiksen ( Glostrup, Denmark) found reduced activation of visual cortex on functional MRI scans in patients with optic neuritis as compared with control subjects. THERAPEUTICS In a session on therapeutics, Helmut Wilhelm and Gerd Becker ( Tubingen) reviewed the visual outcomes of 49 patients with optic nerve sheath meningiomas managed at the University of Tubingen from 1994 to 2000 with a mean follow- up period of 52 months. Of 39 patients treated with stereotactic fractionated radiation therapy, none showed visual deterioration and 14 ( 36%) showed some visual improvement. There were no complications. Of 10 patients observed without treatment, 7 ( 70%) showed visual deterioration, 2 ( 20%) remained stable, and 1 ( 10%) improved. The conclusion is obvious: this treatment works and it is not dangerous. Bern-hard Schuknecht ( Zurich), a neuroradiologist, presented the results of intra- arterial injection of urokinase in 19 consecutive patients with acute central retinal artery occlusion within 12 hours of event onset. Complete visual recovery occurred in 26.3% of patients. The authors noted that this outcome is better than that of two previously reported large series ( 12.9% and 17.6%) and of a meta- analysis of all prior reports ( 14%). A large prospective trial is underway in Europe in which patients will be randomized to endovascular thrombolysis, systemic thrombolysis, or no therapy. Mark Kupersmith ( New York) reviewed the records of 94 patients with " ocular myasthenia gravis" and found that only 4 of 58 patients J Neuro- Ophthalmol, Vol. 21, No. 4, 2001 314 NEURO- OPHTHALMOLOGY AT LARGE RETINA Cris Constantinescu ( Nottingham), Irene Gottlob ( Leicester), and Frank Proudlock ( Leicester). ( 7%) treated with prednisone went on to develop " generalized myasthenia gravis" as compared with 13 of 36 untreated patients ( 36%). This is provocative information and may warrant a prospective trial. OPTIC NEUROPATHIES In a session devoted to optic nerve disorders, Chris-tiane Alexander ( London) proposed that mutations in the OPA1 gene are responsible for dominant optic atrophy. In his interpretation of the multicenter trials of " disease-modifying therapy" in multiple sclerosis, Jonathan Trobe ( Ann Arbor) acknowledged that the interferons and glati-ramer have reduced relapse rates and the accumulation of MRI signal abnormalities, but reminded the audience that no drug in any trial has yet shown an impact on neurologic disability. Jost Jonas ( Erlangen) proposed that the disc excavation of glaucoma differs from that following arteritic ischemic optic neuropathy in producing parapapillary retinal pigment epithelium ( RPE) atrophy. Candice Chen, representing Jeff Odel and collaborators ( New York), showed how one could combine a normal multifocal electroretinographic ( ERG) result with an abnormal multifocal VEP result to localize visual loss in a case of papillorenal syndrome to retinal ganglion cells. NEURAL REGENERATION In a session on neural regeneration, Christian Vorwerk ( Leipzig), Solon Thanos ( Minister), and Emiko Adachi- Usami ( Chibar, Japan) presented laboratory studies that show promise in overcoming the central nervous system inhibitors of regeneration, but it was apparent that clinical applications are a long way off. In a session devoted to the retina, Eberhart Zrenner ( Tubingen) pointed out that the RPE has four functions: 1) phagocytosis, 2) retinol transport and storage, 3) ionic homeostasis, and 4) protection from light damage. The key to treating most RPE disorders is finding, cloning, and discovering the function of the aberrant genes. Papers by Hendrik Scholl ( Tubingen), Herbert Jaegle ( Tiibingen), and Anja Palmowski ( Hamburg) pointed out how refinements in the ERG, including the multifocal version, have improved diagnostic sensitivity. Florian Gekeler ( Tubingen) convinced the audience that the Tubingen subretinal prosthesis is feasible but still not able to produce adequate cortical responses. PUPIL The pupil got its own minisymposium, introduced by an elegant summary of its quirks by Stephen Smith ( London), and followed by a review by Barbara Wilhelm ( Tubingen) of the utility of pupillography in refined diagnosis of Adie's and Horner's syndromes, objective perimetry, and in measuring sleepiness. Fion Bremner ( London) compared threshold and pupil perimetry in eight patients with optic neuritis and found much better recovery of visual thresholds than pupillary constriction in the same stimulus positions. He postulated that remy-elination was better in the larger retinogeniculate ( vision) than in the smaller retinotectal ( pupillary) axons. By testing a patient with a dorsal midbrain syndrome with various pupillographic stimuli, John Barbur ( London) suggested that the central sympathetic inhibition of the pupillary response is mediated directly via the Edinger- Westphal nuclei and does not require the pretectal pathways. In a patient with botulism, Helmut Wilhelm ( Tubingen) found, with pupillography, that the pupils constricted well to direct light but not to a near target (" inverse light: near dissociation") and that accommodation was lost. His explanation: the toxin has higher affinity for the ciliary ganglion neurons subserving accommodation and the near response than the light response. Do we really understand these pathways? EYE MOVEMENTS The session on eye movement disorders brought in Charles Pierrot- Deseilligny ( Paris) for a relatively elementary overview of nuclear and supranuclear disorders, followed by an update from Detlef Kompf ( Liibeck) on the role of the human frontal eye fields. According to the latest work, they are involved not only in all types of voluntary saccades and ipsiversive pursuit, but also in visuospatial function ( ordinarily assigned to parietal lobe) and short- term memory ( ordinarily assigned to limbic pathways). Hans- Peter Thier ( Tiibingen) described how his single- unit recordings of monkey cerebellum suggest how populations of Purkinje cells con- / Neuro- Ophthalmol, Vol. 21, No. 4, 2001 NEURO- OPHTHALMOLOGY AT LARGE 315 Closing banquet in the Cloister of Bebenhausen, built in 1183 for the order of Zisterzienser and transformed in 1802 into a hunting castle for the Wuerttenberg kings. tribute to saccadic adaptation. Using tracers injected into extraocular muscles, Jean Btittner- Ennever ( Munich) found that large motoneurons located within motor nuclei innervate twitch fibers, whereas smaller motoneurons located around the edge of the nuclei innervate non-twitch fibers. Irene Gottlob ( Leicester) surveyed the families of patients with spasmus nutans and infantile nystagmus in Philadelphia and found that the patients with spasmus nutans were significantly more often Hispanic or African- American, exposed to lower home luminance, and from poorer families with higher prevalence of psychiatric and social disorders ( alcoholism, drug abuse). One evening was devoted to viewing the 50 posters. With Rhine wine glasses in hand, attendees moved through the exhibit guided by tour leaders, who helped to focus the 5- minute explanations of each poster presenter. There was a bus trip to a Hohenzollern castle on the top of a mountain, and a festive dinner in a 12th century cloister. The organizers secured a grant from the German government to underwrite the expenses of 10 neuro-ophthalmologists making their first trips abroad from Russia and other Eastern European countries. They discovered a gracious medieval setting, a high level of scientific discussion, state- of- the- art audiovisual facilities, a superbly organized meeting, and balmy weather- an unexpected feature to top off an impressive effort by the Tubingen group. Acknowledgment: The author gratefully acknowledges Shlomo Dotan, MD, and Jens Reinhardt for photographs. J Neuro- Ophthalmol, Vol. 21, No. 4, 2001 |