MR-lymphangiography at 3.0T—a feasibility study

Abstract

The purpose of this study was to establish and evaluate contrast-enhanced MR-lymphangiography (MRL) at 3.0 T for detection and visualization of abnormalities of the peripheral lymphatic system. Sixteen patients were examined with a highly resolved isotropic T1w-3D-GRE-(FLASH) sequence (TR 3.76 ms/TE 1.45 ms/FA 30 degrees /voxel-size 0.8 x 0.8 x 0.8 mm(3)) at 3T after intracutaneous injection of gadolinium-diethylene-triamine-pentaacetic-acid. Two radiologists evaluated overall image quality, contrast between lymph vessels and background tissue, venous contamination, visualized levels, and fat-saturation-homogeneity on 3D maximum-intensity projections. Overall image quality was good to excellent, and all examinations were diagnostic except one, where contrast medium was injected subcutaneously instead of intracutaneously. Overall image quality was good to excellent in 12/16 cases, depiction of lymph vessels was good to excellent in 15/16 cases. Venous contamination was always present, but diagnostically problematical in only one case. Instant lymphatic drainage was observed in unaffected extremities, reaching the pelvic level after approximately 10 min. Lymphatic drainage was considerably delayed in lymphedematous extremities. Ectatic lymph vessels, entrapment, and diffuse drainage of contrast medium correlated with impaired lymphatic drainage. In conclusion, MRL at 3.0 T provides very high spatial resolution and anatomical detail of normal and abnormal peripheral lymph vessels. MRL may thus become a valuable tool for microsurgical treatment planning and monitoring.

Seven-Tesla micro-MRI in early detection of acute arterial ischaemia: evolution of findings in an in vivo rat model

“…I vantaggi della RM rispetto alla TC includono una maggiore risoluzione di contrasto per i tessuti molli e l'assenza di rischio da radiazioni ionizzanti o di nefropatie indotte da mezzi di contrasto iodati. L'indagine TC mantiene una risoluzione spaziale superiore, ma questa differenza si va riducendo grazie all'introduzione di nuove sequenze per la RM addominale con voxel dell'ordine di 2 mm per apparecchiature da 1,5 T e di 1 mm per apparecchiature da 3 T [12,15].…”

“…Le anse dell'ileo presentavano la stessa evoluzione ma lo spasmo si osservava a circa 1 ora e l'ipotono a 4 ore. contrast media. The CT scan still has a higher spatial resolution, but the difference is becoming less evident with the introduction of new abdominal MRI sequences with voxels in the order of 2 mm for 1.5-T scanners and of 1 mm for 3-T scanners [12,15].…”

Quantitative and Morphologic Change Associated with Breast Cancer-Related Lymphedema. Comparison of 3.0T MRI to External Measures

“…Other tools include perometry for volume measurements, 20 bioimpedance spectroscopy for changes in electrical conductance, 21,22 tonometry for changes in skin texture and resistance, 23 ultrasound, 24,25 computed tomography, 5 and magnetic resonance imaging. [26][27][28] Circumferential measurements have been found to have a strong correlation with water volumetry, [29][30][31] and because of their ease of application are the most frequently used clinical measure. 18 One clinical approach utilizes a specialized measuring tape, Gulic measuring tape, which has a built-in tension device that gauges how tightly the tape is pressed against the skin to prevent excess compression of tissue.…”

Die MR-Lymphangiografie in der präoperativen Diagnostik des fokalen „dermal backflow“ bei peripheren Lymphödemen

“…Mit der MR-Lymphangiografi e kann die gesamte Extremität in mehreren Schritten mit einer hohen räumlichen und zeitlichen Aufl ösung untersucht werden [ 7 , 8 ] , zudem können dynamische Informationen über die Aufnahme des Kontrastmittels in die inguinalen Lymphknoten gewonnen werden [ 6 ] . Eine Untersuchung bei 3,0 Tesla ergibt eine Aufl ösung im Submillimeterbereich, sodass Verlauf und Konfiguration der Lymphgefäße besser dargestellt werden können [ 8 ] . Mit der MR-Lymphangiografi e können Lymphgefäße identifi ziert werden, die für potentiell als Empfänger-oder Spendergefäße bei der Lymphgefäßtransplantation geeignet sind und mögliche topografi sche Areale für Lymphbahn-Anastomosen können bestimmt werden [ 3 , 6 ] .…”

“…zur Ableitung der Lymphe vor Lymphozelen oder vor Lymphfi steln [ 3 ] . Da die verwendeten Gadolinium-Chelate wasserlöslich sind und durch Diff usion in die Lymphgefäße gelangen, kann durch Diff usion in die venösen Blutleiter eine venöse Kontamination, d. h. venöse Überlagerungseff ekte entstehen, die zu einer eingeschränkten Beurteilung der Lymphgefäße führen können [ 8 ] . Im Gegensatz dazu ist der bei der Lymphszintigrafi e verwendete kolloidgebundene Tracer 99 m Tc äußerst spezifi sch für das lymphatische System.…”