For educational and reference use only. These calculators do not replace clinical judgement, local protocols, or a qualified clinician. Verify every result independently before it informs patient care.
Neuroradiology
Knosp Classification
Knosp grade of parasellar (cavernous sinus) extension of a pituitary macroadenoma, based on its relation to lines drawn through the intra- and supracavernous internal carotid arteries on coronal MRI.
Result
Grade 0
Within the medial tangent, no cavernous sinus extension.
Formula
Grade 0–4 by the adenoma’s position relative to the medial tangent, intercarotid line and lateral tangent of the cavernous/supracavernous ICA (grade 3 split into 3A superior / 3B inferior).
References
- Knosp E, et al. Pituitary adenomas with invasion of the cavernous sinus space. Neurosurgery 1993;33:610–617.
- Micko AS, Wöhrer A, Wolfsberger S, Knosp E. Invasion of the cavernous sinus space in pituitary adenomas: endoscopic verification and its correlation with an MRI-based classification. J Neurosurg 2015;122(4):803–811.
Disclaimer
The invasion rates are from Micko 2015, an ENDOSCOPIC series; the same grades read microscopically gave far higher rates (grade 2: 88%). Grades 3B and 4 predict a high rate of surgically confirmed invasion; grades 0–2 rarely invade. Assess on coronal images through the ICAs.
For educational and reference use only. These calculators do not replace clinical judgement, local protocols, or a qualified clinician. Verify every result independently before it informs patient care.
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