Elsevier

World Neurosurgery

Volume 96, December 2016, Pages 36-46
World Neurosurgery

Literature Review
Cavernous Sinus Invasion in Pituitary Adenomas: Systematic Review and Pooled Data Meta-Analysis of Radiologic Criteria and Comparison of Endoscopic and Microscopic Surgery

https://doi.org/10.1016/j.wneu.2016.08.088Get rights and content

Background

Despite the substantial impact of cavernous sinus invasion (CSI) in pituitary adenoma surgery, its radiologic determination has been inconsistent and variable, and the role of endonasal endoscopic surgery has been unclear. This is a systematic review and pooled data meta-analysis of the literature to ascertain the best radiologic criteria for CSI and verify the efficacy and safety of an endonasal endoscopic approach.

Methods

We searched the MEDLINE database (1993–2015) to identify studies on radiologic criteria for CSI and endonasal surgery. Using PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, the studies included were reviewed for CSI criteria, gross total resection (GTR), endocrine remission, cranial nerve deficits, carotid injury, and other complications.

Results

The prevalence of CSI was 43% radiographically compared with 18% intraoperatively (P < 0.001). The radiologic criteria of inferolateral venous compartment obliteration and Knosp 3–4 had the highest correlation with intraoperative CSI and the lowest correlation with GTR. Microscopy had significantly overestimated intraoperative CSI compared with endoscopy (P < 0.001) for each Knosp grade. Endoscopy had significantly higher GTR than did microscopy particularly for Knosp 3–4 (47% vs. 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% showed 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.

Conclusions

Knosp 3–4 remains the best objective indicator of CSI. Microscopy tends to overestimate intraoperative CSI compared with endoscopy. Among pituitary adenomas with CSI, GTR in endoscopic series is higher than microscopy and improves with experience without significant additional morbidity.

Introduction

The encroachment of cavernous sinus (CS) by pituitary adenomas, often termed CS invasion (CSI), is the most common and significant risk factor for their incomplete surgical resection.1, 2, 3, 4 Whether it is true invasion suggesting an aggressive process or mere opportunistic intrusion into the weak wall of the CS, the determination of CSI has been problematic. The varied radiologic criteria described are not universally accepted and may not reliably determine invasion. Direct observation is hence considered more accurate than radiology in the absence of histologic assessment of the integrity of the medial wall of CS, which is often not feasible.5, 6, 7 Nevertheless, direct observation too can be inaccurate depending on who is observing, with what degree of exposure, and potentially misleading because tumor has to be removed to evaluate the integrity of the medial CS wall.8, 9, 10, 11, 12, 13 These limitations have resulted in variable and inconsistent reports on the impact of CSI on pituitary adenoma surgery.14, 15, 16, 17, 18, 19

Endonasal endoscopic approaches to sella have often highlighted the panoramic view offered by the endoscope as one of the major advantages over the microscopic approach.2, 18, 20 The feasibility of wider exposure and the use of angled endoscopes have expanded surgical corridors to expose medial as well as lateral CS.2, 15, 21 Several investigators have reported on the enhanced surgical access to the CS with endoscope. However, these reports have generally been single-center series without direct comparison to microscope-based data.1, 2, 4, 15 Also, the efficacy and safety of endonasal endoscopic transcavernous approaches are still a matter of debate, compared with standard nonsurgical options such as stereotactic radiosurgery or radiotherapy in dealing with CS residual tumors.17, 22, 23

In this study, we performed a systematic literature review to examine how well radiographic criteria for CSI correlate with detection of CSI during surgery. We also assessed the efficacy of an endoscopic approach compared with a microscopic approach at removing pituitary tumors invading the CS. All series were included for the diagnostic evaluation of radiologic criteria for intraoperative CSI. However, for the comparative assessment of surgical efficacy between microscopic and endoscopic methods, only the series having arms of both components were included, because many of the sole microscopic series had patients either with unclear CS invasion with respect to resection rates or not comparable with the endoscopic series. The safety of an endonasal endoscopic approach for pituitary adenomas with CSI was also evaluated.

Section snippets

Study Selection

We performed a literature search using the PubMed gateway of the MEDLINE database. The following keywords were queried singly and in combination between the publication years 1993 and 2015: “pituitary adenoma”, “cavernous sinus”, “endonasal”, “trans-nasal”, and “endoscopy”. The search was limited to case series either in English or with an available English translation, and humans were specified as the study category. Reports published before 1993, when magnetic resonance imaging was less

Study Selection

A total of 112 published studies were identified through our initial search, of which 72 were rejected because they did not include original data; were purely anatomic, technical, or case reports; did not report CSI, GTR, or ER; included a mixture of approaches; or repeated data reported elsewhere. A total of 40 studies were included in this review (Figure 1).

CSI was variably defined as per the operative evidence, distinct criteria,20, 27, 28 or KS grades 2–414, 29, 30 or 3–431, 32, 33, 34, 35

Discussion

The enormous variations in reported prevalence of CSI based on direct intraoperative observation (9%2, 17–30%19) compared with radiographic assessment (30%28–63%29) in pituitary adenomas show the ambiguity in defining CSI. Our meta-analysis noted a significantly higher prevalence of CSI radiographically (43%) than the intraoperative findings (18%) suggest.

Several radiologic criteria have been described in the literature to predict the intraoperative evidence of CSI. Although KS grades were

References (48)

  • X. Bao et al.

    Extended transsphenoidal approach for pituitary adenomas invading the cavernous sinus using multiple complementary techniques

    Pituitary

    (2016)
  • M. Taniguchi et al.

    Endoscopic endonasal transsellar approach for laterally extended pituitary adenomas: volumetric analysis of cavernous sinus invasion

    Pituitary

    (2015)
  • M.B. Goncalves et al.

    Cavernous sinus medial wall: dural or fibrous layer? Systematic review of the literature

    Neurosurg Rev

    (2012)
  • H. Nishioka et al.

    Aggressive transsphenoidal resection of tumors invading the cavernous sinus in patients with acromegaly: predictive factors, strategies, and outcomes

    J Neurosurg

    (2014)
  • Y. Diao et al.

    Is there an identifiable intact medial wall of the cavernous sinus? Macro- and microscopic anatomical study using sheet plastination

    Neurosurgery

    (2013)
  • P. Cappabianca et al.

    Surgical complications associated with the endoscopic endonasal transsphenoidal approach for pituitary adenomas

    J Neurosurg

    (2002)
  • J.P. Cottier et al.

    Cavernous sinus invasion by pituitary adenoma: MR imaging

    Radiology

    (2000)
  • A.R. Dehdashti et al.

    Current state of the art in the diagnosis and surgical treatment of Cushing disease: early experience with a purely endoscopic endonasal technique

    Neurosurg Focus

    (2007)
  • H.D. Jho et al.

    Endoscopic endonasal transsphenoidal surgery: experience with 50 patients

    J Neurosurg

    (1997)
  • D.L. Stofko et al.

    The value of immediate postoperative MR imaging following endoscopic endonasal pituitary surgery

    Acta Neurochir (Wien)

    (2014)
  • S. Ceylan et al.

    Endoscopic endonasal transsphenoidal approach for pituitary adenomas invading the cavernous sinus

    J Neurosurg

    (2010)
  • A.R. Dehdashti et al.

    Pure endoscopic endonasal approach for pituitary adenomas: early surgical results in 200 patients and comparison with previous microsurgical series

    Neurosurgery

    (2008)
  • A.S. Micko et al.

    Invasion of the cavernous sinus space in pituitary adenomas: endoscopic verification and its correlation with an MRI-based classification

    J Neurosurg

    (2015)
  • A. Paluzzi et al.

    Endoscopic endonasal approach for pituitary adenomas: a series of 555 patients

    Pituitary

    (2014)
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    Conflict of interest statement: The authors declare that the article content was composed in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

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