02541nas a2200253 4500008004100000022001400041245013200055210007100187260002600258300001400284490000700298520172500305100002102030700002102051700002402072700002302096700002802119700002302147700001502170700002002185700001802205700001602223856004802239 2003 eng d a0033-832X00a3D-Querschnittsprofil des Laryngotrachealtrakts—Eine neue Methode zur Visualisierung und Quantifizierung von Trachealstenosen0 a3DQuerschnittsprofil des Laryngotrachealtrakts—Eine neue Methode bSpringer-Verlagc2003 a1056-10680 v433 a

Purpose

Demonstration of a technique for 3D assessment of tracheal stenoses, regarding site, length and degree, based on spiral computed tomography (S-CT).

Patients and Methods

S-CT scanning and automated segmentation of the laryngo-tracheal tract (LTT) was followed by the extraction of the LTT medial axis using a skeletonisation algorithm. Orthogonal to the medial axis the LTT 3D cross sectional profile was computed and presented as line charts, where degree and length were obtained. Values for both parameters were compared between 36 patients and 18 normal controls separately. Accuracy and precision was derived from 17 phantom studies.

Results

Average degree and length of tracheal stenoses were found to be 60.5% and 4.32 cm in patients compared to minor caliber changes of 8.8% and 2.31 cm in normal controls (p <0.005). For the phantoms an excellent correlation between the true and computed 3D cross sectional profile was found (p <0.005) and an accuray for length and degree measurements of 2.14 mm and 2.53% respectively could be determined. The corresponding figures for the precision were found to be 0.92 mm and 2.56%.

Conclusion

LTT 3D cross sectional profiles permit objective, accurate and precise assessment of LTT caliber changes. Minor LTT caliber changes can be observed even in normals and, in case of an otherwise normal S-CT study, can be regarded as artefacts.

 

1 aSorantin, Erich.1 aHalmai, Csongor.1 aErdőhelyi, Balázs1 aPalágyi, Kálmán1 aNyúl, László, Gábor1 aOllé, Krisztián.1 aGeiger, B.1 aLindbichler, F.1 aFriedrich, G.1 aKiesler, K. uhttp://dx.doi.org/10.1007/s00117-003-0990-8