Your SlideShare is downloading. ×
A Closer Look Into Optic Nerve Gliomas
Upcoming SlideShare
Loading in...5
×

Thanks for flagging this SlideShare!

Oops! An error has occurred.

×
Saving this for later? Get the SlideShare app to save on your phone or tablet. Read anywhere, anytime – even offline.
Text the download link to your phone
Standard text messaging rates apply

A Closer Look Into Optic Nerve Gliomas

4,882

Published on

0 Comments
3 Likes
Statistics
Notes
  • Be the first to comment

No Downloads
Views
Total Views
4,882
On Slideshare
0
From Embeds
0
Number of Embeds
0
Actions
Shares
0
Downloads
0
Comments
0
Likes
3
Embeds 0
No embeds

Report content
Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
No notes for slide
  • Transcript

    • 1. A CLOSER LOOK INTO OPTIC NERVE GLIOMAS A Presentation By Jamie Annand and Angela Brasz
    • 2. OPTIC NERVE GLIOMA
      • What is it?
        • Low-grade astrocytoma of the optic nerve
        • Prevalence in both adults and children
        • May be situated anteriorly or posteriorly in the optic nerve
      • Childhood ONG
        • Roughly 5% of all childhood brain tumours
        • Age of onset: 6 months to 10 years
      • Adult ONG
        • Very rare version of adult
        • astrocytoma
        • Age of onset: 22 years to 79 years
    • 3. ADULT AND CHILD PATHOLOGY
      • Tumour more commonly malignant
      • Infiltrates hypothalamus and temporal lobe
      • Prognosis is poor
      • Treatment has not been shown to prolong life
      • Tumour usually benign
      • Does not tend to metastasize
      • Prognosis is good
      • Growth patterns unpredictable
      • Difficult to determine treatment
      • Adult Form of ONG
      • Child Form of ONG
    • 4. NEUROFIBROMATOSIS-1 (NF-1)
      • Autosomal dominant genetic disorder
      • Probably some combination of genetic and environmental factors
      • ONG may occur with or without the presence of NF-1
        • Patients with NF-1 do not necessarily develop ONG
      • ONG with NF-1 is indicative of a better prognosis
    • 5. A STUDY
      • Study by Kornreich, 2001
      • Hospitals involved: Sick Children Hospital in Canada and the Schneider Children’s Medical Center of Israel
      • All known to have optic nerve gliomas. Those not presenting symptoms were biopsied to confirm diagnosis
      • Assessments were performed using both Magnetic Resonance Imaging (MRI) and Computed Tomography (CT)
      • All patients with progressive tumour signs underwent chemotherapy treatment
    • 6. STUDY INVOLVING THE PRESENCE AND ABSENCE OF NF-1 IN ONG
      • 10-38% with NF-1 develop ONG
      • Symptoms present 32% of time
      • Most common site of involvement: Orbital Nerve (66% of patients)
      • Tumour in general smaller
      • Original shape of optic nerve maintained
      • Symptoms present 100% of time
      • Most common site of involvement: Chiasm and Hypothalamus (91% of patients)
      • Maximal diameter and volume of tumour significantly greater
      • Tumour was mass-like with extension beyond optic pathways
      • Optic Nerve Glioma With NF-1
      • Optic Nerve Glioma Without NF-1
    • 7. SIGNS AND SYMPTOMS OF CHILDHOOD OPTIC NERVE GLIOMA
      • The most common sign of ONG is progressive loss of vision
      • Other major symptoms include:
        • Changes in visual acuity
        • Proptosis may occur in later stages
        • Involuntary eye movements
        • Changes in appetite and sleep
        • Neurologic deficits
          • Nausea, headache and vomiting
          • Caused by obstructive hydrocephalus
      • Rarely, childhood Optic Nerve Glioma can result in death
    • 8. IMAGING OPTIC NERVE GLIOMAS
      • RADIOGRAPHY
        • Plain films used
        • Orbits imaged
      • ANGIOGRAPHY
        • Not currently used
        • Examined blood vessels around the orbit
      • COMPUTED TOMOGRAPHY
        • Great soft tissue definition
        • Also visualizes bony detail
      • MAGNETIC RESONANCE IMAGING
        • Currently GOLD STANDARD in tumor imaging
        • Superior contrast resolution of soft tissue structures
    • 9. WHY COMPUTED TOMOGRAPHY?
      • Often used for diagnosis and elimination of differential diagnosis
      • Can detect subtle erosions or expansions of optic canal indicative of optic nerve glioma
      • Has the option of reformatting images to better visualize pathology
      • Can use several algorithms which mathematically change the contrast
      • and brightness settings
      (Auntminnie, 2008)
    • 10. WHAT'S SO GREAT ABOUT MAGNETIC RESONANCE IMAGING?
      • Currently the Gold Standard in optic nerve glioma imaging
      • Superior nervous tissue differentiation
        • Allows for better visualization of
        • subtle lesions
      • Best for visualizing nerves
      • and nerve pathways
      • No Dose
      (Auntminnie, 2008) Axial Protocol Contrast Gadolinium Scan Type Axial Scanning Area Midlevel of maxillary sinuses to mid-portion of frontal sinuses Slice Thickness 3-5mm Spacing 1-2mm In-Plane Resolution 256 x 192 or 256 x 256 Coronal Protocol Contrast Gadolinium Scan Type Coronal Scanning Area Posterior globe through cavernous sinus to posterior aspect of brain stem Slice Thickness 3-5mm Spacing 1-2mm In-Plane Resolution 256 x 192 or 256 x 256
    • 11. A COMPARISON
      • Inferior contrast resolution to MRI
      • Better with calcifications and bony detail than MRI
      • High amounts of dose
      • Large availability
      • Shorter scan times
      • Less expensive
      • Superior contrast resolution to CT
      • Subtle changes in the optic nerve better visualized with MRI
      • No dose
      • Availability limited
      • Longer scan times
      • More expensive
      • Computed Tomography
      • Magnetic Resonance Imaging
    • 12. FUTURE IMPLICATIONS OF IMAGING
      • PET-CT SCAN
        • Helpful in staging of the disease
        • Effectively locates the tumour which is useful for treatment
        • Can assess tumour progression/recession following treatment
        • Allows the possibility for a less invasive technique that could easily replace more invasive ones
      • PET-MRI SCAN
        • Same application as a PET-CT scanner
        • Better soft tissue than CT
        • More expensive
    • 13. MORE IMPLICATIONS OF FUTURE IMAGING
      • MAGNETIC RESONANCE SPECTROSCOPY (MRS)
        • MRI with non-invasive characterization of tissue
        • spectroscopic patterns of gliomas different than normal brain tissue
        • potentially help in delineating tumour spread
      • VISUAL EVOKED POTENTIALS (VEPs)
        • uses electroencephalography to evaluate conduction of visual pathway from optic nerve through optic chiasm to occipital cortex
        • useful in detecting anterior visual pathway disturbance
        • Findings indicate that results may not be reliable for children under 5 years old (peak age for ONG)
    • 14. TREATING OPTIC NERVE GLIOMA’S
      • Goal of Treatment:
        • To halt the progression in vision loss or tumour growth
      • Types of treatment include: surgery, chemotherapy and radiation therapy
      • Treatment is started when imaging studies show continuous tumor progression or vision deterioration
      • Treatment will rarely restore vision loss, but is very successful in decreasing the tumor size or stopping its growth
      • After treatment patient should be monitored for further vision loss and the effect of treatment
    • 15. RADIATION THERAPY
      • Preferred method for children over 6 years of age 15 years ago
      • Major side effects of cranial irradiation:
        • Mental retardation
        • Endocrinopathies
        • Cerebrovascular disease
      • Fortunately side effects are less common today due to treatments that are more precisely focused on abnormal tissue
    • 16. CHEMOTHERAPY
      • First line treatment 15 years ago in patients under 6 years of age or younger
      • In the last 10 years chemotherapy has now been determined as the best form of treatment for all ages
      • Due To:
        • Toxicity of Radiation Therapy for all age groups
      • If Chemotherapy fails,
      • radiation therapy is then used
    • 17. A COMPARISON
      • Side effects can be more serious
      • High dose to patient
      • Should only be used if chemotherapy not effective
      • Most common side effect is nausea
      • No radiation dose
      • Should be used initially
      • Radiation Therapy
      • Chemotherapy
    • 18. FUTURE IMPLICATIONS FOR TREATMENT
      • By far the most controversial issue related to ONG
      • FRACTIONATED STEREOTACTIC RADIOTHERAPY
        • A more controlled beam of radiation is used
        • Prevents increased dose to nearby tissue
        • CT SIM is used to plan procedure
      • GAMMA KNIFE
        • highly focused x-ray beams make up a “knife” which “cuts” through diseased tissue
        • Allows for more precisely targeted tumour tissue that may be located deeper in the brain
        • Recovery time is shorter and the procedure itself is painless
    • 19. CONCLUSION
      • Optic nerve gliomas are a common primary brain tumour in children
      • Although they are seen as mostly benign and slow growing, there is increasing concern in the treatment of these tumours
      • It is now believed that the tumour should be treated directly when vision loss or notable progression of the tumour becomes apparent
      • New imaging and treatment options can be used to help with earlier detection, more accurate treatment planning and better prognosis
    • 20. THANK YOU FOR YOUR ATTENTION!
      • References
      • Agamanoliz, D.P. (n.d.). Neuropathology. Retrieved March 13, 2008, from http://www.neuropathologyweb.org/ .
      • Anonymous. (2004). Apache Server. March 13, 2008, from http://sol.sci.uop.edu/manual/.
      • Anonymous. (2008). GE Medcyclopaedia. March 13, 2008, from http://www.medcyclopaedia.com/ .
      • Anonymous. (2005). Scanners to give research boost. March 13, 2008, from http://news.bbc.co.uk/2/hi/uk_news/england/north_yorkshire/4218431.stm  
      • Auntminnie Case of the Day. (2008) Childhood Optic Nerve Glioma. Retrieved from: http://education.auntminnie.com/auntminnie .  
      • Carlson, A.H. (2007). Siemens Demonstrates Prototype MRI-PET System. March 13, 2008, from http://images.google.com/imgres?imgurl=http://www.medicalimagingmag.com.
      • Gujar, S., Maheshwari, S., Bjorkman-Burtscher, I. & Sundgren, P. (2005) Magnetic resonance spectroscopy. Journal of Neuro-opthalmology, 25 (3), 217-226. 
      • Hollander, M.D., Fitzpatrick, M., O’Connor, S.G., Flanders, A.E., Tartaglino, L.M. (1999). Optic Gliomas. Imaging in Ophthalmology, 37 (1), 59-71.
      • Huszar, L. (2006) Clinical Utility of Evoked Potentials. Retrieved from: http://www.emedicine.com/NEURO/topic69.htm .  
      • Kansas, S. (n.d.). Salina Regional Health Center. March 13, 2008, from http://www.srhc.com/ .
      • Kornreich, L., Blaser, S., Schwarz, M., Shuper, A., Vishne, T.H., Cohen, I.J., Faingold, R., Michovitz, S., Koplewitz, B., Horev, G. (2001). Optic pathway glioma: correlation of imaging findings with the presence of neurofibromatosis. American Journal of Neuroradiology, 22 , 1963-1969.
      • Listernick, R., Louis, D., Packer, R. & Gutmann, D. (1997) Optic Pathway Gliomas in Children with Neurofibromatosis 1: Consensus Statement from the NF1 Optic Pathway Glioma Task Force . Annals of Neurology , 41 (2), 143-149.
      • Liu, G.T. (2006). Optic gliomas of the anterior visual pathway. Current opinion in ophthalmology, 17 , 427-431.
      • Martin, N.A. (2007). UCLA Neurosurgery. March 13, 2008, from http://www.neurosurgery.ucla.edu/
      • Shuper, A., Horev, G., Kornreich, L., Michowiz, S., Weitz, R., Zaizov, R., Cohen, I.J. (1997). Visual pathway glioma: an erratic tumour with therapeutic dilemmas. Archives of disease in childhood, 76 , 529-263.
      • Woodcock, R. (2007) Optic Nerve Glioma. Retrieved from: http://www.emedicine.com/Radio/topic486.htm .

    ×