Optic Pathway Gliomas Robert A. Avery, DO, MSCE Gilbert Family Neurofibromatosis Institute Center for Neuroscience and Behavior Children s National Medical Center and Departments of Neurology, Ophthalmology & Pediatrics George Washington University Washington, DC Disclosures Conflict of interest: none Financial support: K23 EY022673-03, National Eye Institute Gilbert Family NF Institute Children s Tumor Foundation Goals and Objectives Optic Pathway Gliomas (OPG) Understand the epidemiology of optic pathway gliomas (OPGs) List the appropriate ophthalmologic tests and exam frequency. Learn about current research using OCT in children with OPGs. Sievert, J. Child Neurology 2009 Epidemiology of OPGs Sporadic OPGs: occur at any age, although most < 8 y.o. Outcomes of OPGs Sporadic OPGs: -Most cause vision loss -Vision loss typically more severe NF1-related OPGs: -Neurofibromatosis type 1 -symptomatic between 18m and 8 years NF1-related OPGs: -<50% cause vision loss -most w/ mild-moderate vision loss 1
Neurofibromatosis Type 1 Incidence of 1:3,000 births NF1 (N = 100) + OPG No OPG (N = 20) (N = 80) 3 y.o. recently diagnosed with NF1 Acuity OD: 20/30 OS: 20/30 Avoid unnecessary treatment No Vision Loss (N = 10) Vision Loss (N = 10) Optimize vision outcomes Pupil: no rapd Fundus: normal Visual field: full to confrontation VA tested every 3-6 months and remains normal for age. At 5yo, a repeat MRI 5 y.o. with progressive NF1-OPG Acuity Color OD: 20/20 9/9 OS: 20/20 9/9 Fundus: normal Chemotherapy deferred..no symptoms! 2
Case 2 Case 2 5 y.o. with sporadic OPG Acuity Color OD: 20/40 6/8 OS: 20/25 8/8 Pupil: no rapd Fundus: optic nerve pallor OU Visual field: full to confrontation Case 2 Stable VA on serial examinations 8 yo able to complete HVF testing Case 2 VA/VF was stable until 12 yo, then decreased OD from 20/25 to 20/50 Case 2 VA/VF was stable until 12 yo, then decreased OD from 20/25 to 20/50 Chemotherapy initiated Summary of Cases Both had OPGs demonstrated tumor growth on MRI but without any vision loss Case 2 had a stable MRI with vision loss Case 2 had VA loss on two separate occasions 3
OPG Clinical Challenges MRI change/stability is not a good indicator of disease progression. No reliable clinical predictor of impending vision loss. Young children with OPGs are frequently uncooperative with VA/VF testing. Avery, Bouffet, Packer, Reginald, 2013 Ophthalmology Exam Recommendations NF1 Asymptomatic/no OPG < 8yo, yearly exam > 8yo, every 2 years until 18yo Newly Diagnosed NF1-OPG q3 months x 1 year, if stable -then q6 months until 8 yo -then yearly exam until 18yo Listernick, Ferner, Liu, Gutmann, 2007 Avery, Fisher, Liu, 2011 Ophthalmology Exam Recommendations Symptomatic/known OPG New Dx: q3 months x 1 year, -then q6 months if stable On treatment: q3 months during and for 1 year after treatment. Ophthalmology Exam Quantitative VA Testing Preferential looking tasks (Teller or Cardiff) for younger children. Age-appropriate recognition acuity for older kids (LEA, HOTV, Snellen). Use of VEP is controversial. Avery, Fisher, Liu, 2011 Avery, Bouffet, Packer, Reginald, 2013 Avery, Ferner, Listernick et al, 2012 Siatkowski, 2006 Visual Field Testing Attempt VF to confrontation, but limited sensitivity in younger patients. HVF or GVF when old enough. What Constitutes Progression? Visual acuity: 0.2 logmar New visual field defect MRI progression visual progression 4
MRI and OPGs Screening MRI is not recommended for asymptomatic children with NF1.* OPGs can develop after normal MRI Role of the Ophthalmologist Visual acuity and visual field loss is the primary indication for treatment! Must communicate your concerns with other providers. -Especially when MRI is stable! Listernick, Ferner, Liu, Gutmann, 2007 Listernick, Charrow, Greenwald, 1992 NF1 or Sporadic OPG Vision testing q3-6 months Can RNFL or GCL-IPL thickness be used as a surrogate marker of vision? OPG Diagnosed OPG Unable causes to assess vision vision loss Treatment with chemo OCT Child is uncooperative, but RNFL/GCLIPL is normal/stable OPG Diagnosed Observe and limit MRIs X Treatment with chemo Standard OCT imaging can reliably be performed in healthy children 7 years. Children with NF1-OPGs typically experience vision loss between 18 months and 6 yrs. -comorbid ADHD/dev. delay 5
Hand-Held OCT Benefits of Hand-Held OCT Acquired during clinically indicated MRI. No additional sedation/anesthesia needed. 1) Stable RNFL/GCLIPL could support deferring chemotherapy. 2) Detect declining RNFL/GCLIPL before VA/VF loss, thereby permitting early treatment? Longitudinal OCT analysis currently underway. -multi-center study needed to validate utility of OCT. 3) OCT should NOT be used to screen/diagnose NF1-OPGs. Summary Quantitative VA assessment is required in all children with OPGs. Thank you VA, not MRI, change is paramount. Vision loss is more frequent and severe in sporadic OPGs vs NF1. Longitudinal OCT studies are needed to validate its use in clinical care. 6