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Background
In wrist arthrograms, aberrant contrast material is frequently seen extending into the soft tissue adjacent to the ulnar styloid process. Since the prestyloid recess can mimic contrast leakage in CT arthrography, this study aims to provide a detailed analysis of its morphologic variability, while investigating whether actual ulnar-sided leakage is associated with injuries of the triangular fibrocartilage complex (TFCC).
Methods
Eighty-six patients with positive wrist trauma history underwent multi-compartment CT arthrography (40 women, median age 44.5 years). Studies were reviewed by two board-certified radiologists, who documented the morphology of the prestyloid recess regarding size, opening type, shape and position, as well as the presence or absence of ulnar-sided contrast leakage. Correlations between leakage and the presence of TFCC injuries were assessed using the mean square contingency coefficient (r\(_{ɸ}\)).
Results
The most common configuration of the prestyloid recess included a narrow opening (73.26%; width 2.26 ± 1.43 mm), saccular shape (66.28%), and palmar position compared to the styloid process (55.81%). Its mean length and anterior–posterior diameter were 6.89 ± 2.36 and 5.05 ± 1.97 mm, respectively. Ulnar-sided contrast leakage was reported in 29 patients (33.72%) with a mean extent of 12.30 ± 5.31 mm. Leakage occurred more often in patients with ulnar-sided TFCC injuries (r\(_{ɸ}\) = 0.480; p < 0.001), whereas no association was found for lesions of the central articular disc (r\(_{ɸ}\) = 0.172; p = 0.111).
Conclusions
Since ulnar-sided contrast leakage is more common in patients with peripheral TFCC injuries, distinction between an atypical configuration of the prestyloid recess and actual leakage is important in CT arthrography of the wrist.
Cone-beam computed tomography is a powerful tool for 3D imaging of the appendicular skeleton, facilitating detailed visualization of bone microarchitecture. This study evaluated various combinations of acquisition and reconstruction parameters for the cone-beam CT mode of a twin robotic x-ray system in cadaveric wrist and elbow scans, aiming to define the best possible trade-off between image quality and radiation dose. Images were acquired with different combinations of tube voltage and tube current–time product, resulting in five scan protocols with varying volume CT dose indices: full-dose (FD; 17.4 mGy), low-dose (LD; 4.5 mGy), ultra-low-dose (ULD; 1.15 mGy), modulated low-dose (mLD; 0.6 mGy) and modulated ultra-low-dose (mULD; 0.29 mGy). Each set of projection data was reconstructed with three convolution kernels (very sharp [Ur77], sharp [Br69], intermediate [Br62]). Five radiologists subjectively assessed the image quality of cortical bone, cancellous bone and soft tissue using seven-point scales. Irrespective of the reconstruction kernel, overall image quality of every FD, LD and ULD scan was deemed suitable for diagnostic use in contrast to mLD (very sharp/sharp/intermediate: 60/55/70%) and mULD (0/3/5%). Superior depiction of cortical and cancellous bone was achieved in FD\(_{Ur77}\) and LD\(_{Ur77}\) examinations (p < 0.001) with LD\(_{Ur77}\) scans also providing favorable bone visualization compared to FD\(_{Br69}\) and FD\(_{Br62}\) (p < 0.001). Fleiss’ kappa was 0.618 (0.594–0.641; p < 0.001), indicating substantial interrater reliability. In this study, we demonstrate that considerable dose reduction can be realized while maintaining diagnostic image quality in upper extremity joint scans with the cone-beam CT mode of a twin robotic x-ray system. Application of sharper convolution kernels for image reconstruction facilitates superior display of bone microarchitecture.
Objectives
Trauma evaluation of extremities can be challenging in conventional radiography. A multi-use x-ray system with cone-beam CT (CBCT) option facilitates ancillary 3-D imaging without repositioning. We assessed the clinical value of CBCT scans by analyzing the influence of additional findings on therapy.
Methods
Ninety-two patients underwent radiography and subsequent CBCT imaging with the twin robotic scanner (76 wrist/hand/finger and 16 ankle/foot/toe trauma scans). Reports by on-call radiologists before and after CBCT were compared regarding fracture detection, joint affliction, comminuted injuries, and diagnostic confidence. An orthopedic surgeon recommended therapy based on reported findings. Surgical reports (N = 52) and clinical follow-up (N = 85) were used as reference standard.
Results
CBCT detected more fractures (83/64 of 85), joint involvements (69/53 of 71), and multi-fragment situations (68/50 of 70) than radiography (all p < 0.001). Six fractures suspected in radiographs were ruled out by CBCT. Treatment changes based on additional information from CBCT were recommended in 29 patients (31.5%). While agreement between advised therapy before CBCT and actual treatment was moderate (κ = 0.41 [95% confidence interval 0.35–0.47]; p < 0.001), agreement after CBCT was almost perfect (κ = 0.88 [0.83–0.93]; p < 0.001). Diagnostic confidence increased considerably for CBCT studies (p < 0.001). Median effective dose for CBCT was 4.3 μSv [3.3–5.3 μSv] compared to 0.2 μSv [0.1–0.2 μSv] for radiography.
Conclusions
CBCT provides advantages for the evaluation of acute small bone and joint trauma by detecting and excluding extremity fractures and fracture-related findings more reliably than radiographs. Additional findings induced therapy change in one third of patients, suggesting substantial clinical impact.
Background:
Triangular fibrocartilage complex (TFCC) lesions commonly cause ulnar-sided wrist pain and instability of the distal radioulnar joint. Due to its triangular shape, discontinuity of the TFCC is oftentimes difficult to visualize in radiological standard planes. Radial multiplanar reconstructions (MPR) may have the potential to simplify diagnosis in CT wrist arthrography. The objective of this study was to assess diagnostic advantages provided by radial MPR over standard planes for TFCC lesions in CT arthrography.
Methods:
One hundred six patients (49 women, 57 men; mean age 44.2 ± 15.8 years) underwent CT imaging after wrist arthrography. Two radiologists (R1, R2) retrospectively analyzed three randomized datasets for each CT arthrography. One set contained axial, coronal and sagittal planes (MPR\(_{Standard}\)), while the other two included an additional radial reconstruction with the rotating center either atop the ulnar styloid (MPR\(_{Styloid}\)) or in the ulnar fovea (MPR\(_{Fovea}\)). Readers evaluated TFCC differentiability and condition. Suspected lesions were categorized using Palmer’s and Atzei’s classification and diagnostic confidence was stated on a fivepoint Likert scale.
Results:
Compared to standard planes, differentiability of the superficial and deep TFCC layer was superior in radial reconstructions (R1/R2; MPR\(_{Fovea}\): p < 0.001; MPRStyloid: p ≤ 0.007). Palmer and Atzei lesions were present in 86.8% (92/106) and 52.8% (56/106) of patients, respectively. Specificity, sensitivity and accuracy for central Palmer lesions did not differ in radial and standard MPR. For peripheral Atzei lesions, sensitivity (MPR\(_{Standard}\) 78.6%/80.4%, MPR\(_{Styloid}\) 94.6%/94.6%, MPR\(_{Fovea}\) 91.1%/89.3%) and accuracy (MPR\(_{Standard}\) 86.8%/86.8%, MPR\(_{Styloid}\) 96.2%/96.2%, MPR\(_{Fovea}\) 94.3%/93.4%) improved with additional styloid-centered (p = 0.004/0.008) and foveacentered (p = 0.039/0.125) reconstructions. No substantial difference was observed between both radial MPR (p = 0.688/0.250). Interrater agreement was almost perfect for each dataset (κ\(_{Standard}\) = 0.876, κ\(_{Styloid}\) = 0.894, κ\(_{Fovea}\) = 0.949). Diagnostic confidence increased with addition of either radial MPR (p < 0.001).
Conclusions:
Ancillary radial planes improve accuracy and diagnostic confidence for detection of peripheral TFCC lesions in CT arthrography of the wrist.
Background
Elbow imaging is challenging with conventional multidetector computed tomography (MDCT), while cone-beam CT (CBCT) provides superior options. We compared intra-individually CBCT versus MDCT image quality in cadaveric elbows.
Methods
A twin robotic x-ray system with new CBCT mode and a high-resolution clinical MDCT were compared in 16 cadaveric elbows. Both systems were operated with a dedicated low-dose (LD) protocol (equivalent volume CT dose index [CTDI\(_{vol(16 cm)}\)] = 3.3 mGy) and a regular clinical scan dose (RD) protocol (CTDI\(_{vol(16 cm)}\) = 13.8 mGy). Image quality was evaluated by two radiologists (R1 and R2) on a seven-point Likert scale, and estimation of signal intensity in cancellous bone was conducted. Wilcoxon signed-rank tests and intraclass correlation coefficient (ICC) statistics were used.
Results
The CBCT prototype provided superior subjective image quality compared to MDCT scans (for RD, p ≤ 0.004; for LD, p ≤ 0.001). Image quality was rated very good or excellent in 100% of the cases by both readers for RD CBCT, 100% (R1) and 93.8% (R2) for LD CBCT, 62.6% and 43.8% for RD MDCT, and 0.0% and 0.0% for LD MDCT. Single-measure ICC was 0.95 (95% confidence interval 0.91–0.97; p < 0.001). Software-based assessment supported subjective findings with less “undecided” pixels in CBCT than dose-equivalent MDCT (p < 0.001). No significant difference was found between LD CBCT and RD MDCT.
Conclusions
In cadaveric elbow studies, the tested cone-beam CT prototype delivered superior image quality compared to high-end multidetector CT and showed a potential for considerable dose reduction.
Es wurden 133 Patienten mit VA-ECMO Therapie nach kardiogenem Schock im Zeitraum zwischen 01/2009 und 07/2016 in der Klinik für Herz, Thorax,- und thorakale Gefäßchirurgie des Unisveritätsklinikums Würzburg dahingehend untersucht, ob sich die intrahospitale Mortalität in der Gruppe der zentral kanülierten Patienten von der der peripher kanülierten Patienten unterscheidet. Zudem wurden Unterschiede der präoperativen Charakteristika und postoperativen Komplikationen erfasst und ausgewertet. Bei nicht signifikant unterschiedlicher intrahospitaler Mortalität, bietet der zentrale ECMO-Zugang den Vorteil einer signifikant geringeren Komplikationsrate bezüglich der Häufigkeit lokaler Blutungen am Kanülierungsort, der Menge an benötigten Erythrozytenkonzentraten, des Auftretens des Harlekin Syndrom und dem Bedarf der linksventrikulären Entlastung mittels einer Impella Pumpe. So trat das Harlekin Syndrom in der P-Gruppe in 13 Fällen auf, jedoch in keinem Fall innerhalb der Z-Gruppe (p=0,003). Der Transfusionsbedarf an Erythrozytenkonzentraten war in der Z-Gruppe ebenfalls niedriger (Z-Gruppe: 10,8±10,2 vs. P-Gruppe: 14,4±10,1;p=0,005). Die Thrombozytenkonzentrattransfusionen zeigten ebenfalls einen Trend zugunsten der zentralen Kanülierung (Z-Gruppe: 1,7±2,3 vs. P-Gruppe: 2,5±2,9; p=0,123). Die Entlastung des linken Ventrikels mithilfe einer Impella Pumpe war bei 15 Patienten der P-Gruppe notwendig und nur bei einem Patienten der Z-Gruppe (17,0% vs 2,2%, p=0,045). Die Anzahl der Schlaganfälle, Nierenversagen und peripheren Ischämien waren ähnlich. Ebenso zeigten die Gruppen keine Unterschiede bezüglich der Weaningraten (62,2% vs. 53,4%, p=0,858), sowie des Intrahospitalgesamtüberlebens (22,1% vs 30,7%, p=0,471).
Es kann gefolgert werden, dass eine thorakale aortale Kanülierung eine geringere Rate an Komplikationen aufweist, weniger Personal- und Materialressourcen beansprucht, bedingt durch weniger Revisionseingriffe, reduzierten Transfusionsbedarf, weniger zusätzliche Kanülen für eine linksventrikuläre
Entlastung und periphere Extremitätenperfusion. Jedoch bietet die zentrale Kanülierung keinen Vorteil bezüglich der Mortalität.
Die retrospektiven Daten sprechen für einen Vorteil des zentralen Zugangs. Hinsichtlich der Mortalität bestätigt dies auch der Vergleich mit der Metaanalyse von Raffa et al. aus dem Jahr 2019. [10] Bezüglich der postoperativen Komplikationen ergeben sich jedoch Unterschiede in unserem Patientenklientel, in dem die zentrale Kanülierung mit geringeren Komplikationen verbunden war. Möglicherweise ist dies auf die häufige Verwendung der zentralen ECMO Kanülierung und entsprechend hohe Erfahrungswerte mit dieser zurückzuführen. Insbesondere bei Kardiotomiepatienten, die bereits intraaoperativ die Zugangswege des kardiopulmonalen Bypass aufweisen, kann die zentrale Kanülierung mit ihrem antegraden Fluss eine bessere linksventrikuläre Drainage bieten. Dies zeigt sich an einer geringeren Rate an Harlekin Syndromen. Insgesamt muss die vorwiegend retrospektive Datenlage und das auch in der Metaanalyse von Raffa et al. inhomogenem Patientenklientel mit geringer Patientenzahl der einbezogenen Studien limitierend erwähnt werden. Diese Ergebnisse sollten im Rahmen größerer multizentrischer Studien oder einer Registerstudie überprüft werden.