Jenny E Dornberger1,2, Grit Rademacher3, Dirk Stengel4,5,6, Alexander Hönning5, Gabriele Schüler Dipl-Phys, Andreas Eisenschenk2,7, Sven Mutze3,8, Leonie Goelz3,8. 1. J. E. Dornberger, Burn Centre with Plastic Surgery, BG Klinikum Unfallkrankenhaus Berlin, Berlin, Germany. 2. J. E. Dornberger, A. Eisenschenk, Department of Hand, Replantation and Microsurgery, BG Klinikum Unfallkrankenhaus Berlin, Berlin, Germany. 3. G. Rademacher, G. Schüler, S. Mutze, L. Goelz, Department of Radiology and Neuroradiology, BG Klinikum Unfallkrankenhaus Berlin, Germany. 4. D. Stengel, BG Kliniken-Klinikverbund der Gesetzlichen Unfallversicherung gGmbH, Berlin, Germany. 5. D. Stengel, A. Hönning, Center for Clinical Research, BG Klinikum Unfallkrankenhaus Berlin, Germany. 6. D. Stengel, Department of Trauma and Orthopaedic Surgery, BG Klinikum Unfallkrankenhaus Berlin, Berlin, Germany. 7. A. Eisenschenk, Department of Hand Surgery and Microsurgery, University Medicine Greifswald, Greifswald, Germany. 8. S. Mutze, L. Goelz, Institute for Diagnostic Radiology and Neuroradiology, University Medicine Greifswald, Greifswald, Germany.
Abstract
BACKGROUND: Cone beam CT (CBCT) is a widely available technique with possible indications in carpal ligament injuries. The accuracy of CBCT arthrography in diagnosing traumatic tears of the scapholunate ligament has not been reported. QUESTIONS/PURPOSES: (1) What is the diagnostic accuracy of CBCT and how does it relate to the accuracy of multislice CT arthrography and conventional arthrography in diagnosing scapholunate ligament tears? (2) What is the estimated magnitude of skin radiation doses of each method? METHODS: This secondary analysis of a previous prospective study included 71 men and women with suspected scapholunate ligament tears and indications for arthroscopy. Preoperative imaging was conventional arthrography and either MSCT arthrography for the first half of patients to be included (n = 36) or flat-panel CBCT arthrography for the remaining patients (n = 35). Index tests identified therapy-relevant SLL tears with dorsal or complete SLL ruptures, and these tears were compared with relevant SLL tears which were determined through arthroscopy as Geissler Stadium III and IV by probing the instable SL joint with a microhook or arthroscope. These injuries were treated by open ligament repair and Kirschner wire fixation. Accuracy values and 95% confidence intervals were calculated. Additional estimates of the radiation skin doses of each CBCT exam and two MSCT protocols were subsequently calculated using dose area products, dose length products, and CT dose indices. RESULTS: The diagnostic accuracy was high for all imaging methods. 95% CIs were broadly overlapping and therefore did not indicate differences between the diagnostic groups: Sensitivity of CBCT arthrography was 100% (95% CI 77 to 100), specificity was 95% (95% CI 76 to 99.9), positive predictive value was 93% (95% CI 68 to 99.8), and negative predictive value was 100% (95% CI 83 to 100). For MSCT arthrography, the sensitivity was 92% (95% CI 64 to 99.8), specificity was 96% (95% CI 78 to 99.9), positive predictive value was 92% (95% CI 64 to 99.8), and negative predictive value was 96% (95% CI 78 to 99.9). For conventional arthrography, the sensitivity was comparably high: 96% (95% CI 81 to 99.9). Specificity was (81% [95% CI 67 to 92]); the positive predictive value was 77% (95% CI 59 to 89) and negative predictive value was 97% (95% CI 86 to 99.9). Estimated mean (range) radiation skin doses were reported in a descriptive fashion and were 12.9 mSv (4.5 to 24.9) for conventional arthrography, and 3.2 mSv (2.0 to 4.8) for CBCT arthrography. Estimated radiation skin doses were 0.2 mSv and 12 mSv for MSCT arthrography, depending on the protocol. CONCLUSION: Flat-panel CBCT arthrography can be recommended as an accurate technique to diagnose scapholunate ligament injuries after wrist trauma. Estimated skin doses are low for CBCT arthrography and adapted MSCT arthrography protocols. LEVEL OF EVIDENCE: Level III, diagnostic study.
BACKGROUND: Cone beam CT (CBCT) is a widely available technique with possible indications in carpal ligament injuries. The accuracy of CBCT arthrography in diagnosing traumatic tears of the scapholunate ligament has not been reported. QUESTIONS/PURPOSES: (1) What is the diagnostic accuracy of CBCT and how does it relate to the accuracy of multislice CT arthrography and conventional arthrography in diagnosing scapholunate ligament tears? (2) What is the estimated magnitude of skin radiation doses of each method? METHODS: This secondary analysis of a previous prospective study included 71 men and women with suspected scapholunate ligament tears and indications for arthroscopy. Preoperative imaging was conventional arthrography and either MSCT arthrography for the first half of patients to be included (n = 36) or flat-panel CBCT arthrography for the remaining patients (n = 35). Index tests identified therapy-relevant SLL tears with dorsal or complete SLL ruptures, and these tears were compared with relevant SLL tears which were determined through arthroscopy as Geissler Stadium III and IV by probing the instable SL joint with a microhook or arthroscope. These injuries were treated by open ligament repair and Kirschner wire fixation. Accuracy values and 95% confidence intervals were calculated. Additional estimates of the radiation skin doses of each CBCT exam and two MSCT protocols were subsequently calculated using dose area products, dose length products, and CT dose indices. RESULTS: The diagnostic accuracy was high for all imaging methods. 95% CIs were broadly overlapping and therefore did not indicate differences between the diagnostic groups: Sensitivity of CBCT arthrography was 100% (95% CI 77 to 100), specificity was 95% (95% CI 76 to 99.9), positive predictive value was 93% (95% CI 68 to 99.8), and negative predictive value was 100% (95% CI 83 to 100). For MSCT arthrography, the sensitivity was 92% (95% CI 64 to 99.8), specificity was 96% (95% CI 78 to 99.9), positive predictive value was 92% (95% CI 64 to 99.8), and negative predictive value was 96% (95% CI 78 to 99.9). For conventional arthrography, the sensitivity was comparably high: 96% (95% CI 81 to 99.9). Specificity was (81% [95% CI 67 to 92]); the positive predictive value was 77% (95% CI 59 to 89) and negative predictive value was 97% (95% CI 86 to 99.9). Estimated mean (range) radiation skin doses were reported in a descriptive fashion and were 12.9 mSv (4.5 to 24.9) for conventional arthrography, and 3.2 mSv (2.0 to 4.8) for CBCT arthrography. Estimated radiation skin doses were 0.2 mSv and 12 mSv for MSCT arthrography, depending on the protocol. CONCLUSION: Flat-panel CBCT arthrography can be recommended as an accurate technique to diagnose scapholunate ligament injuries after wrist trauma. Estimated skin doses are low for CBCT arthrography and adapted MSCT arthrography protocols. LEVEL OF EVIDENCE: Level III, diagnostic study.
Authors: Luis Cerezal; Juan de Dios Berná-Mestre; Ana Canga; Eva Llopis; Alejandro Rolon; Xavier Martín-Oliva; Francisco del Piñal Journal: Semin Musculoskelet Radiol Date: 2012-03-23 Impact factor: 1.777
Authors: Reeta Ramdhian-Wihlm; Jean-Marie Le Minor; Matthieu Schmittbuhl; Jeremy Jeantroux; Peter Mac Mahon; Francis Veillon; Jean-Claude Dosch; Jean-Louis Dietemann; Guillaume Bierry Journal: Skeletal Radiol Date: 2011-11-08 Impact factor: 2.199
Authors: Ryan K L Lee; Alex W H Ng; Cina S L Tong; James F Griffith; W L Tse; C Wong; P C Ho Journal: Skeletal Radiol Date: 2013-06-28 Impact factor: 2.199