PNA Medical Corner: Cavernous Sinus Invasion
This month the PNA Medical Corner focuses on a study coauthored by Theodore Schwartz, a PNA member and past recipient of our highest honor, the Gentle Giant Award. The study is called Cavernous Sinus Invasion in Pituitary Adenomas: Systematic Review and Pooled Data Meta-analysis of Radiological Criteria and Comparison of Endoscopic and Microscopic Surgery. It appeared in the August 30th edition of the journal World Neurosurgery and found that Knosp 3-4 is the best indicator of cavernous sinus invasion in pituitary tumors.
World Neurosurg. 2016 Aug 30. pii: S1878-8750(16)30771-9. doi: 10.1016/j.wneu.2016.08.088. [Epub ahead of print]
Cavernous Sinus Invasion in Pituitary Adenomas: Systematic Review and Pooled Data Meta-analysis of Radiological Criteria and Comparison of Endoscopic and Microscopic Surgery.
Dhandapani S1, Singh H2, Negm HM3, Cohen S4, Anand VK5, Schwartz TH6.
Despite the substantial impact of cavernous sinus invasion (CSI) in pituitary adenoma surgery, its radiological determination has been inconsistent and variable, with unclear role of endonasal endoscopic surgery. This is a systematic review and pooled data meta-analysis of literature to ascertain the best radiological criteria for CSI, and verify the efficacy and safety of endonasal endoscopic approach.
We searched MEDLINE database(1993-2015) to identify studies on radiological criteria for CSI, and endonasal surgery. Using PRISMA guidelines, the included studies were reviewed for CSI criteria, gross total resection(GTR), endocrine remission(ER), cranial nerve(CN) deficits, carotid injury and other complications.
The prevalence of CSI was 43% radiographically as compared with 18% intra-operatively (p<0.001). The radiological criteria of inferolateral venous compartment obliteration (ILVCO) and Knosp 3-4 had highest correlation with intra-operative CSI and lowest correlation with gross total resection(GTR). Microscopy had significantly overestimated intra-operative CSI compared with endoscopy(p<0.001) for each Knosp grade. Endoscopy had significantly higher GTR than microscopy particularly for Knosp 3-4(47% versus 21%;p=0.001). Carotid injury and cranial nerve deficits occurred in 0.9% and 5% respectively with endoscopy. Among endoscopic series with CSI, GTR% demonstrated significant correlation with number of patients in the series(p<0.01), but no correlation with complications, indicating the relative safety of endonasal endoscopy in experienced hands for removing tumors with CSI.
Knosp 3-4 remains the best objective indicator of CSI. Microscopy tends to overestimate intra-operative CSI compared to endoscopy. Among pituitary adenomas with CSI, GTR in endoscopic series is higher than microscopy, and improves with experience without significant additional morbidity.