Magnetic resonance imaging of the lymph nodes: comparison with CT.

Abstract

This retrospective study of 144 patients was made to (a) assess the potential of magnetic resonance (MR) for demonstrating lymph nodes using spin-echo technique, (b) compare the MR results with those of CT, and (c) determine the optimal pulse-sequence interval (TR) and echo-delay time (TE) for imaging lymph nodes. The reported CT findings on normal lymph nodes were compared with MR findings in 60 patients who underwent MR imaging of the neck (20 patients), chest (20 patients), abdomen (10 patients), and pelvis (10 patients) for conditions other than lymph node disease. The results showed that CT is presently better than MR for imaging neck and abdominal lymph nodes less than 13 mm in diameter. The ability of MR to demonstrate normal-size (less than 10 mm) lymph nodes in the chest was comparable to that of CT. In addition, MR scans of 84 patients with proven abnormal lymph nodes (8 neck, 49 chest, and 27 abdomen and pelvis) were assessed: in 72 patients, these nodes had also been imaged by CT. MR and CT gave similar results with abnormal lymph nodes (greater than 13 or 15 mm), but MR displayed these nodes better because of its excellent soft-tissue contrast resolution. MR can clearly differentiate abnormal lymph nodes from normal fat, muscle, vessels, adult thymus, thyroid, and diaphragmatic crura, as well as from primary tumor and lymphoceles. Optimal demonstration of lymph nodes with MR required two sequences: one with a short TR and one with a long TR and long TE. Preliminary results indicate that MR holds great promise for the demonstration of lymph nodes in every part of the body.

Staging of Pelvic Lymph Nodes in Neoplasms of the Bladder and Prostate by Positron Emission Tomography with 2-[¹⁸F]-2-Deoxy-<i>D</i>-Glucose

“…In bladder cancer, tumor metastases in regional lymph nodes cannot be detected by CT or pedal lymphangiography in 30–40% of the patients. MRI was found to be more sensitive than CT; the minimum size of detectable lymph nodes was observed to range between 7 and 11 mm [4, 5, 6]. Similar findings have been reported for the detection of lymph node metastases by CT and MRI in prostate cancer [6, 7].…”

“…MRI was found to be more sensitive than CT; the minimum size of detectable lymph nodes was observed to range between 7 and 11 mm [4, 5, 6]. Similar findings have been reported for the detection of lymph node metastases by CT and MRI in prostate cancer [6, 7]. Due to the low accuracy of conventional imaging methods, selection of the appropriate therapy is based on histopathological examination of pelvic lymph nodes dissected by pelvic lymphadenectomy.…”

“…Pedal lymphangiography lacks specificity, whereas CT and MRI lack sensitivity, especially if the diameter of lymph node metastases does not exceed 1–1.5 cm [4, 5, 6, 7, 8]. …”

Ovarian Dysgerminoma with Massive Metastases to Para-Aortic Lymph Nodes

“…These imaging modalities are also useful for the postoperative evaluation of the residual lymph nodes. However, small lymph node metastases less than 1 cm in diameter cannot be detected by MRI or CT [7].…”

The use of MRI in planning radiotherapy for gynaecological tumours

“…Russell et al, in 1992, reported for the first time on the value of pelvic MRI in designing the lateral fields of the box technique [5] . MRI offers the possibility of visualising the anatomy of the pelvis on all planes and enables much better evaluation of soft tissue structures and tumour depiction than CT [11][12][13][14][15][16] . Russell [3,6,7] .…”