Haneder, S.S.HanederMichaely, H.J.H.J.MichaelyKonstandin, S.S.KonstandinSchad, L.R.L.R.SchadMorelli, J.N.J.N.MorelliKrämer, B.K.B.K.KrämerSchoenberg, S.O.S.O.SchoenbergLammert, A.A.Lammert2022-03-042022-03-042014https://publica.fraunhofer.de/handle/publica/23846210.1007/s10334-013-0377-4Purpose The purpose of this prospective study was to assess physiologic changes in the renal corticomedullary 23Na-concentration ([23Na]) gradient with 23Na-MRI at 3.0T in patients with central diabetes insipidus (CDI) before and after intranasal administration of 20 mg desmopressin (DDAVP). Methods and materials Four patients with CDI (all male, mean age 60.2 years) were included in this IRB-approved study. For 23Na-imaging, a 3D density adapted, radial GRE-sequence (TE = 0.55 ms; TR = 120 ms; projections = 8,000; spatial resolution = 5 × 5 × 5 mm3) was used in combination with a dedicated 23Na-coil and reference phantoms. The corticomedullary [23Na] gradient (in mmol/L/mm) was calculated pixel-by-pixel along a linear region-of-interest (ROI) spanning from the renal cortex in the direction of the medulla. Mean ± SDs of [23Na] were calculated for each patient as well as for the entire group. Results Mean [23Na] increased along the corticomedullary gradient from the cortex (pre-DDAVP 38.0 ± 6.3 mmol/L vs. post-DDAVP 30.7 ± 3.5 mmol/L) to the medulla (pre-DDAVP 71.6 ± 14.8 mmol/L vs. post-DDAVP 59.7 ± 10.8 mmol/L). The overall mean decrease of [23Na] after DDAVP administration was 17.1 ± 1.1 %. Conclusion 23Na-MRI with state-of-the-art techniques at 3T depicts the physiologic renal response to the administration of desmopressin in patients with central diabetes insipidus.enjournal article