Abstract
Objective This study was aimed to study the current use of intraoperative indocyanine green
(ICG) angiography during skull base reconstruction and understand its efficacy in
predicting postoperative magnetic resonance imaging (MRI) enhancement and flap.
Study Design The Embase, the Cochrane Central Register of Controlled Trials (CENTRAL), Web of
Science, and Google Scholar databases were searched from the date of inception until
August 2020 for studies of ICG flap perfusion assessment during skull base reconstruction.
The primary outcome of interest was the development of cerebrospinal fluid (CSF) leak
after skull base reconstruction. Secondary outcomes of interest included postoperative
meningitis, flap MRI enhancement, flap necrosis, flap perfusion measurements, and
total complications.
Results Search results yielded 189 studies, from which seven studies with a total of 104
patients were included in the final analysis. There were 44 nasoseptal flaps (NSF),
two lateral nasal wall flaps (LNWF), 14 pericranial flaps (PCF), and 44 microvascular
free flaps. The rates of CSF leak and postoperative MRI enhancement were 11 and 94%,
respectively. There was one case of postoperative meningitis. Pooled analysis of the
available data showed that intraoperative ICG flap perfusion was associated with flap
enhancement on postoperative MRI (p = 0.008) and CSF leak (p = 0.315) by Fisher's exact test.
Conclusion The available literature suggests intraoperative ICG enhancement is associated with
postoperative MRI enhancement. Given the small sample sizes in the literature and
the rarity of complications associated with skull base reconstruction, intraoperative
ICG enhancement has not been predictive of flap necrosis or postoperative complications
such as CSF leak or meningitis.
Level of Evidence This study presents level 3 evidence as a systematic review of case studies, case
reports, and retrospective and prospective trials with no blinding, controls, and
inconsistently applied reference standards.
Keywords
indocyanine green angiography - skull base reconstruction - nasal flap - MRI - endoscopic
surgery