Abstract
The North American Neuro-ophthalmology Society (NANOS) holds an annual meeting to update neuro-ophthalmologists, neurologists, ophthalmologists, other clinical scientists, as well as students, residents and fellows on advances in conditions that affect the visual pathways. Each annual meeting educates physicians with clinical pathologic correlations (Frank B Walsh session), symposia on topics of special interest, special lectures and original research, which is presented in platform and poster sessions. This years sessions were extraordinary with the largest attendance in NANOS history – 591 registrants largely from the USA but approximately 20% from 23 other countries.
The Frank B Walsh Session is a dedicated day for clinicopathologic cases presented by neuro-ophthlamologists. Since the clinicopathologic cases focus on radiologists and pathology, expert neuro-radiologist, Carlos Bazan III (University of Texas, TX, USA) and neuropathologist Dennis K Burns (University of Texas Southwestern Medical Center, TX, USA) provided expert commentary on 20 interesting cases. The session was chaired by Jack Carter (University of Texas). The best Walsh paper this year was by Lindsey De Lott and co-authors from the University of Michigan (MI, USA); her paper entitled ‘CS Eye’ detailed a 56-year-old man with several episodes of transient monocular visual loss. His clinical features suggested giant cell arteritis (erythrocyte sedimentation rate and C-reactive protein elevation) along with eosinophilia. The temporal artery biopsy revealed an eosinophilic vasculitis that allowed the diagnosis of Churg–Strauss syndrome. They concluded that the temporal artery biopsy may be helpful even if giant cell arteritis is not diagnosed, and to consider vasculitis in the differential diagnosis of transient monocular visual loss.
The symposia
The first symposium was ‘The other optic neuropathies not the horses: The Zebras’ chaired by Lynn Gordon (University of California, Los Angeles, CA, USA) and Alfredo Sadun (Doheny Eye Institute, CA, USA). Kenneth Schindler (University of Pennsylvania, PA, USA) discussed autoimmune/inflammatory optic neuropathies, including steroid responsive optic neuropathies associated with systemic lupus and sarcoidosis and neuromyelitis optica. He announced that neuromyelitis optica antibodies do play a pathologic role in the disorder and that newer treatments looking at blocking neuromyelitis optica antibodies are on the horizon Citation[1]. Guest Valerio Carelli from the University of Bologna, Italy, reviewed Leber’s Hereditary Optic neuropathy including clinical features of visual loss, other dominant optic atrophies that are mitochondrial related, and treatment options for mitochondrial optic neuropathies including vitamins, antioxidants such as coenyme Q10, and idebenone. Alfredo Sadun brought to our attention many optic neuropathies, not only from toxins and vitamin deficiencies, but also antibiotics, especially ethambutol, and linezolid used for methacillin-resistant Staphylococcus aureus. Ethambutol toxicity to the optic nerve is dose related and individuals should receive no more than 20 mg/kg and those with renal excretion problems and the elderly should have doses reduced. Syndromic mitochondrial optic neuropathies reviewed by Nancy Newman (Emory University School of Medicine, AL, USA) reviewed numerous genetic syndromes including Wolfram Syndrome (diabetes mellitus, diabetes insipidus and hearing loss), Behr’s syndrome (complicated hereditary infantile optic atrophy). She also discussed hereditary ataxias that have optic neuropathies such as Friedreich’s Ataxia and hereditary polyneuropathies. Marie Acierno (LSU Health Science Center, LA, USA) discussed HIV-associated optic neuropathy; she cautioned us that if we have not seen a case of primary HIV optic neuropathy it is because we have not been looking. She also cautioned us that HIV-infected individuals are high risk for optic neuropathies (secondary infectious, ischemic, demyelinative) and as a result of therapy (antiretroviral therapy triggering Leber’s hereditary optic neuropathy).
We were treated to a debate on the work up of atypical optic neuropathies with Deborah Friedman (University of Texas Southwestern Medical Center) arguing to use diagnostic tests such as optical coherence tomography to help make a diagnosis, and Jonathan Trobe (University of Michigan, MI, USA) countering with other tests to make the diagnosis.
‘What’s New in Pediatrics’ moderated by Michael Brodsky (Mayo Clinic, MN, USA) and Grant Liu (University of Pennsylvania) was outstanding. Grant Lui reviewed diagnostic differences and similarities in children and adults with common conditions of idiopathic intracranial hypertension, ocular myasthenia gravis, optic neuritis and Horner’s syndrome.
Two lectures deserve special attention. Michael Brodsky discussed the accessory optic system – the fugitive visual control system in infantile strabismus. The vesitial visual system receives little attention but its three nuclei lie at the mesodiencephalic border. Here they receive direct retinal input from the accessory optic tract which courses over the brachium of the superior colliculus. This nucleus receives multiple complex inputs and is responsible for dissociated eye movements (e.g., dissociated vertical deviation) and oblique muscle over-action. Hence it has direct ramifications for the development of strabismus in infants.
The other lecture, ‘What’s new (and old) in optic nerve hypoplasia’ by Mark Borchert (Childrens Hospital, Los Angeles, CA, USA) explained the historical confusion about optic nerve hypoplasia and de Morsier’s syndrome Citation[2]. de Morsier coined the term ‘septo-optic dysplasia’ but did not ever describe optic disc hypoplasia. He was interested in the septum pellucidum and its connection with midline brain structures. The septum pellucidum’s absence is only coincidentally associated with any optic nerve abnormality and not associated with optic nerve hypoplasia. The importance, however, of detecting optic nerve hypoplasia is that it is associated with pituitary gland dysfunction in children and very important for evaluating children for pituitary dysfunction.
The final debate of the pediatric symposium centered on whether juvenile pilocytic astrocytomas were hamartomas or malignancy. Cameron Parsa (University of Wisconsin-Madison, WI, USA) argued that these are usually self-limited growths and radiation or chemotherapy should be avoided unless growth is detected; whereas Grant Liu argued that there are marked differences between these hamartomas and neoplasms and that these astrocytomas are neoplasms.
A true treat was the ‘Practical update on nystagmus, vestibular and other motility’ disorders moderated by William Fletcher (University of Calgary, AB, Canada) and Agnes Wong (University of Toronto, ON, Canada). The treat was a David Zee (Johns Hopkins Hospital, MD, USA) and R John Leigh (Case Western Reserve University, OH, USA) video/diagram extravaganza. These two giants in eye movement research, in very clear, erudite lectures, covered ocular motor disorders of the cerebrum and brainstem (Leigh) and ocular motor disorders due to disease of the cerebellum and vestibular systems. Nystagmus (William Fletcher) and saccadic oscillations and intrusions (Shirley Wray, Massachusetts General Hospital, MA, USA) capped the eye movement disorder session. Matthew Thurtell (University of Iowa, IA, USA) discussed treatments available for nystagmus.
The final symposia were ‘Emerging trends in interventional neuroradiology’ moderated by Norah Lincoff and Neil Miller. Miller teamed with Philippe Gailloud (The Johns Hopkins University School of Medicine, MD, USA) to look at neuro-ophthalmic implications of interventional neuroradiology. They reviewed idiopathic intracranial hypertension associated with venous sinus stenosis, treatments of central retinal artery occlusion and direct carotid cavernous sinus/dural cavernous fistulas. The duo reminded everyone of working closely together (neuro-ophthalmology and neuro-radiology) in these complicated cases.
Mark Kupersmith (Roosevelt Hospital, NY, USA) related lessons learned by ‘experts’ in treating neurovascular disorders such as aneurysm, arteriovenous shunt, dural arteriovenous malformation and venous sinus occlusion.
Guest Philippe Gailloud discussed the recent advances in neurointerventional techniques relevant to the neuro-ophthalmologist including catheters, stents and bioactive microcoils.
The last symposium detailed advances in neurosurgery. Amin B Kassam (University of Pittsburgh, PA, USA) detailed newer surgical approaches at the skull base to attend to neuro-ophthalmic problems affecting the visual system. Prem Subramanian (Wilmer Eye Institute, Johns Hopkins Hospital) also detailed the advances in the management of the skull base meningiomas. Tonya Stefko (University of Pittsburgh) discussed the art of management of craniopharyngiomas. Louise Mawn (Vanderbilt Eye Institute, TN, USA) illustrated principles of treatment of bony tumors of the skull base.
The Jacobson Lecture was delivered by Jonathan Trobe, who discussed the lasting scientific contributions of Daniel Jacobson. He highlighted many of Jacobson’s contributions to neuro-ophthalmology and how he went about conducting research.
The scientific platforms (25 platforms) and poster (148 posters) sessions are always important to attendees since these represent the best research in the field. These presentations remind us why attending the annual meeting is a must in keeping up with neuro-ophthalmic disorders.
This year’s research presentations were outstanding. Several deserve mention. Steve Stasheff (University of Iowa) showed improved ganglion cell light responsiveness following pluripotent stem cell transplantation in a model of Leber’s congenital amaurosis. Jeffrey Bennett (University of Colorado, Denver, CO, USA) reported Aquaporumab: an anti-aquaporin-4 monoclonal antibody blocker therapy for neuromyelitis optica – a possible game changer for this devastating disease. Several papers outlined how optical coherence tomography can be useful in papilledema, ischemic optic neuropathy and nerve fiber layer analysis. Ivana De Domenico (University of Utah, UT, USA) presented a mouse model of giant cell arteritis with infection with a Burkholderia pseudomallei-like strain treated with steroids and antibiotics. She showed that treatment with antibiotics alone did not rid the animal of giant cell vasculitis, and that the combination of antibiotics with steroids seem to work better than steroids alone. A preliminary treatment trial with antibiotics and steroids in humans was detailed by Bonnie Keung (Salt Lake City, UT, USA) with promising results.
The Best Abstract Award by a Fellow was Patrick Yu-Wai-Man, (Newcastle University, Newcastle-upon-Tyne, UK). His work on Mitofusin 2 mutations causing mitochondrial instability in Charcot–Marie–Tooth disease detailed how important mitochondrial DNA is to normal cell function.
Karen Schmitt (Vanderbilt Eye Institute) had the best abstract by a resident. Her paper showed that drug delivery to the optic nerve could occur by delivering drug endoscopically and that nanoparticle drug delivery systems are feasible and could be tested in optic nerve disorders.
The medical student award for best abstract went to Mithu Storoni (Moorfields Eye Hospital, London, UK). This paper showed that magnetic resonance imaging could distinguish between neuromyelitis optica spectrum and multiple scelrosis-related optic neuritis based on the appearance of the visual pathways.
Beau Bruce (Emory University Neuro-Ophthalmology Unit, GA, USA) was chosen as the Carlow Young Investigator. He presented some of his work detailing the use of a nonmydriatic ocular fundus camera detecting neurologic and systemic disease in emergency rooms Citation[3].
Besides symposia, platforms and posters other optional sessions provided attendees with learning opportunities. By far, the most popular this year was a hands-on skill transfer session for the examination of eye-movements. Leigh and Zee drew over 100 participants to this optional session that taught how to perform a basic neurovestibular examination, vestibular ocular reflex testing, testing for positional vertigo, gaze testing and ways to bring out nystagmus.
Other sessions included ‘Getting your Manuscript Published’ by Lanning Kline (University of Alabama, AL, USA) and Walter Jay (Loyola University Medical Center, IL, USA); improving neuro-ophthalmology practice at Skip’s Tips by Richard ‘Skip’ Legge (Omaha, NE, USA); and an update on the Neuro-Ophthalmology Virtual Education Library, as well as web-based resources were lead by Nancy Lombardo (University of Utah), Jeanne LeBer (University of Utah) and Edmond Fitzgibbon (National Eye Institute, MD, USA).
Previous NANOS syllabi are available to review on the neuro-ophthalmology virtual educational library Citation[101]. The best of NANOS will appear on that site as well as many videos of the special lectures detailed in this review.
The 39th NANOS meeting will occur 9–14 February 2013 at the Snowbird Ski and Summer Resort at Snowbird, UT, USA. For further information visit: the official website of NANOS Citation[102].
Financial & competing interests disclosure
The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.
No writing assistance was utilized in the production of this manuscript.
References
- Tradtrantip L, Zhang H, Saadoun S et al. Anti-Aquaporin-4 monoclonal antibody blocker therapy for neuromyelitis optica. Ann. Neurol.71(3), 314–22 (2011).
- Borchert M. Reappraisal of the optic nerve hypoplasia syndrome. J. Neuroophthalmol.32(1), 58–67 (2012).
- Bruce BB, Lamirel C, Biousse V et al. Feasibility of nonmydriatic ocular fundus photography in the emergency department: Phase I of the FOTO-ED study. Acad. Emerg. Med.18(9), 928–933 (2011).
Websites
- The Neuro-Ophthalmology Virtual Education Library. http://novel.utah.edu
- North American Neuro-Ophthalmology Society. www.nanosweb.org