title: [Modern ultrasound diagnostics of deep vein thrombosis in lung embolism of unknown origin].
abstract: OBJECTIVE
  We compared innovative ultrasound techniques such as tissue harmonic imaging (THI) and cross-beam technique with speckle reduction imaging (SRI) to conventional fundamental B scan in the diagnosis of deep vein thrombosis.
  
  
  METHODS
  We investigated a total number of 185 patients with clinical symptoms of acute vein thrombosis. We documented the thrombosis in the patients using multifrequency ultrasound probes (5-7 MHz, 6-9 MHz, 9-14 MHz, Logig 9, GE) and recorded ultrasound sequences in fundamental B scan, THI, and cross-beam technique with SRI (grade 2). Three blinded ultrasound investigators ranked the marking of the thrombosis in each of these image modalities and graded them with the numbers 5 = weak, 4 = moderate, 3 = satisfactory, 2 = good, and 1 = excellent. We calculated the median and a t-test for each of these image modalities.
  
  
  RESULTS
  We diagnosed 115 thromboses (62%) in 185 investigated patients. This group could be divided as follows: 11 patients (6%) with three-level thrombosis, 37 patients (20%) with two-level thrombosis, and 67 (36%) with one-level thrombosis. The one-level thrombosis group included five (3%) patients with muscle vein thromboses, seven (4%) cases of thrombophlebitis without involvement of the deep vein system, and three (2%) cases of thrombophlebitis with involvement of the deep vein system. The t-test for unconnected samples showed significant differences (p <0.05) in iliac veins and highly significant differences (p <0.001) in the veins of the lower extremity due to the superior capabilities for detection of thrombosis using the cross-beam technique with SRI compared to THI and the fundamental B scan.
  
  
  CONCLUSIONS
  The use of high-resolution linear ultrasound probes with the concomitant application of THI and cross-beam technique with SRI facilitates the diagnosis of deep vein thrombosis. The employment of these new ultrasound modalities is an advantage in distinguishing the veins from the surrounding tissue structures and helps in evaluating the compressibility of venous vessels.
authors.affiliation: Institut für Klinische Radiologie, Klinikum Grosshadern der Ludwig-Maximilians-Universität München, Marchioninistrasse 15, 81377 Munich, Germany. dirk.clevert@med.uni-muenchen.de
authors.forename: D-A
authors.initials: DA
authors.lastname: Clevert
authors.forename: E M
authors.initials: EM
authors.lastname: Jung
authors.forename: K
authors.initials: K
authors.lastname: Pfister
authors.forename: K
authors.initials: K
authors.lastname: Stock
authors.forename: G
authors.initials: G
authors.lastname: Schulte-Altedorneburg
authors.forename: C
authors.initials: C
authors.lastname: Fink
authors.forename: D-A
authors.initials: DA
authors.lastname: Clevert
authors.forename: M
authors.initials: M
authors.lastname: Reiser
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D008297:Male; D011655:Pulmonary Embolism / Q000150:complications* / Q000000981:diagnostic imaging*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D016037:Single-Blind Method; D014463:Ultrasonography / Q000379:methods*; D020246:Venous Thrombosis / Q000150:complications* / Q000000981:diagnostic imaging*