Comparison of normal facial nerve enhancement at 3T MRI using gadobutrol and gadopentetate dimeglumine

Abstract

Background and purpose The facial nerve is unique among cranial nerves in demonstrating normal enhancement of particular segments. The effect of varying T1 relaxivities of gadolinium-based contrast agents on facial nerve enhancement is unclear. In this study, we assess differences in normal facial nerve enhancement with two different gadolinium-based contrast agents, gadobutrol and gadopentetate dimeglumine. In addition, we evaluate differences in facial nerve enhancement with spin-echo (SE) T1 versus 3D inversion recovery prepared fast spoiled gradient-echo (FSPGR) post-contrast sequences. Methods A total of 140 facial nerves in 70 individuals were evaluated (70 with gadobutrol and 70 with gadopentetate dimeglumine) by two blinded reviewers. Differences in enhancement of facial nerve segments between the two agents were analyzed. Differences in enhancement between SE T1 and FSPGR imaging were also evaluated. Results There was no significant difference in facial nerve enhancement between gadobutrol and gadopentetate dimeglumine. Enhancement was commonly observed in the geniculate, tympanic and mastoid segments (98%-100%) with either contrast agent; enhancement was less common in the labyrinthine segments (9%-14%) and lateral canalicular segment (2%-5%). There was a smaller enhancing proportion of labyrinthine and tympanic segments with FSPGR as compared to SE T1 images with gadobutrol. Conclusion There is no significant difference in overall enhancement of the facial nerve between gadobutrol and gadopentetate dimeglumine. Mild enhancement of the lateral canalicular portion of the facial nerve may be a normal finding. With FSPGR sequence, there is lesser perceived enhancement of the labyrinthine and tympanic segments of the facial nerve with gadobutrol.

Enhancement of cranial nerves in Lyme neuroborreliosis: incidence and correlation with clinical symptoms and prognosis

“…We consider our study sample to be highly representative for LNB patients due to a prospective study design with a high rate of participation among patients treated in- and outside of hospital, and the proportion of subjects with a definite versus a possible LNB diagnosis is in line with other studies [ 5 , 37 ]. Interobserver agreement of enhancement ratings for the important nerve locations is good, as in several other studies using a similar qualitative visual assessment for nerve enhancement [ 11 , 35 , 38 ]. Generalization of the findings concerning outcome may be limited by the subjects undergoing slightly different treatments, but all subjects received adequate treatment and a previous randomized clinical trial found oral doxycycline to be as efficient as intravenous ceftriaxone [ 23 ].…”

Enhancement patterns of the normal facial nerve on three-dimensional T1W fast spin echo MRI

“… 15 It could be speculated that differing physicochemical properties of gadolinium based contrast agents (GBCA) such as viscosity, osmolality and longitudinal relaxivity (r1) as well as injected volume may influence the physiological T1 shortening of the facial nerve and its perineural vascular plexus; however, a previous comparison of normal facial nerve enhancement with gadobutrol and gadopentate dimeglumine did not reveal any significant differences. 6 …”

Signal intensity pattern of the normal oculomotor nerve on contrast-enhanced 3D FLAIR at 3.0 T MRI

“…Signal characteristics and enhancement patterns of each cranial nerve differ as a result of factors such as the presence of the arteriovenous plexus. 22,23 For example, Hong et al. 23 demonstrated that the facial nerve can enhance normally in at least one segment due to the presence of circumneural arteriovenous plexus.…”