Koos grading scale
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At the time the article was created Marcos Gil Alberto da Veiga had no recorded disclosures.View Marcos Gil Alberto da Veiga's current disclosures
At the time the article was last revised Yuranga Weerakkody had no financial relationships to ineligible companies to disclose.View Yuranga Weerakkody's current disclosures
The Koos grading scale 1 is frequently used as a classification system for vestibular schwannomas.
- grade 1: small intracanalicular tumor
- grade 2: small tumor with protrusion into the cerebellopontine cistern (CPA); no contact with the brainstem
- grade 3: tumor occupying the cerebellopontine cistern with no brainstem displacement
- grade 4: large tumor with brainstem and cranial nerve displacement
A recent cross-sectional study 2 proved its inter- and intra-reliability, demonstrating that the Koos classification system is a reliable method.
- 1. Wolfgang T. Koos, Robert F. Spetzler, Johannes Lang. Color Atlas of Microneurosurgery, Volume 1: Intracranial Tumors. (2013) ISBN: 9783131734822
- 2. Erickson N, Erickson SP, Erickson AB et-al. Koos Classification of Vestibular Schwannomas: A Reliability Study. (2019) Neurosurgery. doi:10.1093/neuros/nyy409 - Pubmed