Volume Quantification of Endolymph after Intravenous Administration of a Single Dose of Gadolinium Contrast Agent: Comparison of 18- versus 8-minute Imaging Protocols

Abstract

Purpose: We measured the volume of the endolymphatic space by extending a previously proposed less observer-dependent method of area quantification and compared volume measurements obtained using long (18 min, Image A) and short (8 min, Image B) scan times.Methods: We performed MR imaging of 40 ears in 20 patients with clinically suspected endolymphatic hydrops 4 hours after intravenous administration of single-dose gadolinium-based contrast material (IV-SD-GBCM). Two observers separately measured the ratio of the volume of the endolymph to that of total lymph in the cochlea and vestibule by extending the area ratio measurement method previously reported (Image A and B). The correlation between the values by Image A and B was calculated.Results: We observed a strong linear correlation between Images A and B in the cochlear images; the Pearson's correlation coefficient (r) was 0.928 for Observer A and 0.926 for Observer B (P < 0.001, for all). A strong linear correlation was also observed in the vestibular images; the Pearson's correlation coefficient (r) was 0.962 for Observer A and 0.968 for Observer B (P < 0.001, for all).Conclusion: Measurement of endolymphatic volume after IV-SD-GBCM may be feasible using an MR imaging protocol with a reduced scan time of 8 min. This method might facilitate greater use of endolymphatic hydrops imaging in clinical applications.

Lack of Contrast Enhancement in a Giant Perivascular Space of the Basal Ganglion on Delayed FLAIR Images: Implications for the Glymphatic System

“…Heavily T 2 -weighed MR cisternography and heavily T 2 -weighted three dimensional-Fluid attenuated inversion recovery (3D-FLAIR) were obtained at 3T using previously reported methods. 1 The estimated glomerular filtration rate (eGFR) of this patient was 75.8 mL/min/1.73 m 2 . Heavily T 2 -weighted 3D-FLAIR is quite sensitive and can detect the very low concentrations of GBCA within fluids and less sensitive to flow artifact.…”

Cochlear Lymph Fluid Signal Increase in Patients with Otosclerosis after Intravenous Administration of Gadodiamide

“…We cannot completely exclude the possibility that a difference in GBCM might have affected the results of the present study; however, other patient studies using gadodiamide and gadoteridol with the same inversion time for the PEI have been previously reported. 12 , 28 , 29 These studies suggest that the contrast enhancement effects in the perilymph by gadoteridol or gadodiamide are comparable.…”

Quantification of Endolymphatic Space Volume after Intravenous Administration of a Single Dose of Gadolinium-based Contrast Agent: 3D-real Inversion Recovery versus HYDROPS-Mi2

“…and 7 years (A.T.) of experience in MR imaging manually drew the ROIs along the boundary of the cochlea and the vestibule on all MRC slices according to previously reported methods. 10 The ROIs from the MRC images were copied and pasted onto the HYDROPS-Mi2 and the 3D-real IR images. An example of the ROI segmentation is shown in Fig.…”

“…8,9 We routinely perform EH imaging 4 h after IV-SD-GBCA using a hT 2 W-3D-FLAIR imaging and quantitatively evaluate the volume of the endolymphatic space using HYDROPS-Mi2 images in accordance with previously reported studies. 9,10 During our repeated evaluation of EH using HYDROPS-Mi2 technique, we have occasionally encountered cases with misregistration artifacts. 3D-real inversion recovery (3D-real IR) imaging, which based on phase-sensitive reconstruction, does not require post processing using multiple imaging to delineate the endolymph and perilymph and can reduce the risk of misregistration artifacts.…”