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Purpose Due to the increased protein concentration in the perilymph liquid, FIESTA-C has recently been proposed to assess endolymphatic spaces without administration of contrast media in patients with vestibular schwannoma. The aim of this study was to assess whether vestibular endolymphatic space dilatation, as evaluated with 3D-FIESTA-C sequences, is related to the degree of hearing loss in patients with schwannoma. Materials and methods In this retrospective study (IRB 5995), we performed 3D-FIESTA-C sequences in 32 patients with schwannoma, as diagnosed on the basis of typical image findings. Two radiologists independently checked the visualization and evaluated the volume of the utricle and saccule. Pearson and Spearman tests were used to explore the correlation between the volume of the tumor, the volume of the vestibular endolymphatic space and the degree of hearing loss – as evaluated with the levels of pure-tone average (PTA) and speech recognition threshold (SRT). Results The endolymphatic space can be evaluated in 72% (23 out of 32 patients) of patients with schwannoma on non-contrast 3D-FIESTA-C sequences. The mean saccular, utricular and tumor volume were 3.17 mm3, 14.55 mm3 and 1.74 cm3 respectively. There was a significant correlation between the volume of the utricle and the degree of hearing loss as evaluated with the levels of PTA (p = 0.015) and SRT (p = 0.004). There was no significant correlation between the saccular and tumor volumes and the degree of hearing loss. Conclusion The volume of the utricle in schwannoma patients is related to the degree of hearing loss.

Objectifs Evaluer les performances diagnostiques des sequences encephaliques injectees 3D versus 2D sang noir dans l’evaluation diagnostique de l’arterite a cellules geantes (AGC). Materiel et methodes Dans cette etude multicentrique, nous avons inclus consecutivement 79 patients adresses pour une IRM cerebrale dans le cadre d’une suspicion d’AGC. Deux lecteurs ont relu independamment les sequences injectees 2D et 3D sang noir realisees pour chacun d’entre eux. Ils ont classe le diagnostic d’AGC « positif » ou « negatif » selon leur analyse des arteres extra-crâniennes en utilisant une echelle d’evaluation en 4 points validee par la litterature. Les performances diagnostiques ont ete calculees pour chaque sequence, en prenant comme gold standard la synthese clinique des medecins internistes (criteres de l’ACR). Les performances ont ete comparees en utilisant un test de Mc Nemar. La reproductibilite inter observateur a ete calculee (κ de Cohen). Resultats 51 patients ont ete definitivement classes AGC positif, 28 AGC negatif. La sensibilite et la specificite de l’IRM 3D etaient respectivement de 80 % et 100 %, de l’IRM 2D 70 % et 85 %. La comparaison des performances a montre une superiorite significative de l’IRM 3D face a l’IRM 2D en sensibilite (p = 0,025) et en specificite (p = 0,046). La reproductibilite etait excellente aussi bien en 2D (κ a 0,84) qu’en 3D (κ a 0,82). Conclusion L’IRM 3D est performante dans le diagnostic d’AGC, superieure en sensibilite et en specificite aux sequences de type 2D validees par la litterature.