儿童桡骨颈骨折闭合复位弹性髓内钉固定术与切开复位克氏针固定术疗效分析

Objective To investigate the curative effect and feasibility of closed reduction with elastic intramedullary nailing and open reduction with Kirschner wire fixation in treatment of obviously displaced radial neck fractures in children. Methods From July 2006 to December 2007, 18 children with types Ⅱ and Ⅲ O' Brien radical neck fractures were admitted to Nanjing Children' s Hospital. Of all, six children received open reduction and fixation with Kirschner wire and six weeks of cast immobilization; the other 12 children received closed reduction and fixation with elastic intramedullary nail and three weeks of cast immobilization. The children were followed up for mean 12 months to investigate postoperative functional recovery of the elbow joint and presence of complications. Results All children achieved excellent clinical outcomes, without excessive radial bone growth, early closure of radial bone marrow, bone bridge formation or ectopic calcification around the joint. According to Tibone and Stoltz' s clinical evaluation methods, closed reduction with elastic intramedullary nailing had less trauma, faster recovery, fewer complications and better cosmesis than traditional open reduction with Kirschner wire fixation for children with obviously displaced radial neck fractures. Conclusion Closed reduction with elastic intramedullary nailing is a better option for obviously displaced radial neck fractures in children.     

桡骨小头骨折的治疗

Objective To treat radial head fractures with open reduction and internal fixation, removal of the radial head and artificial joint replacement based on different fracture types to discuss the outcome of these methods and summarize optimal strategy for treatment of radial head fractures. Meth-ods A retrospective study was done on data of 47 patients with 48 radial head fractures treated in our de-partment from November 1999 to May 2008. Among them, nine patients were treated conservatively (all type Mason Ⅰ fractures), 28 treated with open reduction and internal fixation (one patient with type Ma-son Ⅰ fracture, 14 with type Mason Ⅱ and 13 with type Mason Ⅲ), eight with removal of radial head (three patients with type Mason Ⅲ fractures and five with type Ⅳ) and three with artificial joint replace-ment (all type Mason Ⅳ fractures). Results All patients were followed up for average 2.8 years (1-4.4 years). Two patients treated with artificial joint replacement were followed up for six months and three months respectively. According to the Mayo Elbow Performance Index, the excellence rate was 8/9 in conservative treatment, 82% (23/28) in open reduction and internal fixation, 6/8 in removal of the radial head and 3/3 in artificial joint replacement respectively. Conclusions The radial head fracture should be given anatomical reduction for early functional exercise. Conservative treatment can be used for type Mason Ⅰ fractures, open reduction and internal fixation for type Mason Ⅱ , type Mason Ⅲ fractures and part of type Mason Ⅳ fractures. The removal of radial head or mental prosthesis replacement are al-ternative for parte of type Mason Ⅳ fractures that can not attain stable fixation through open reduction and internal fixation.     

桡骨小头骨折的治疗

Objective To treat radial head fractures with open reduction and internal fixation, removal of the radial head and artificial joint replacement based on different fracture types to discuss the outcome of these methods and summarize optimal strategy for treatment of radial head fractures. Meth-ods A retrospective study was done on data of 47 patients with 48 radial head fractures treated in our de-partment from November 1999 to May 2008. Among them, nine patients were treated conservatively (all type Mason Ⅰ fractures), 28 treated with open reduction and internal fixation (one patient with type Ma-son Ⅰ fracture, 14 with type Mason Ⅱ and 13 with type Mason Ⅲ), eight with removal of radial head (three patients with type Mason Ⅲ fractures and five with type Ⅳ) and three with artificial joint replace-ment (all type Mason Ⅳ fractures). Results All patients were followed up for average 2.8 years (1-4.4 years). Two patients treated with artificial joint replacement were followed up for six months and three months respectively. According to the Mayo Elbow Performance Index, the excellence rate was 8/9 in conservative treatment, 82% (23/28) in open reduction and internal fixation, 6/8 in removal of the radial head and 3/3 in artificial joint replacement respectively. Conclusions The radial head fracture should be given anatomical reduction for early functional exercise. Conservative treatment can be used for type Mason Ⅰ fractures, open reduction and internal fixation for type Mason Ⅱ , type Mason Ⅲ fractures and part of type Mason Ⅳ fractures. The removal of radial head or mental prosthesis replacement are al-ternative for parte of type Mason Ⅳ fractures that can not attain stable fixation through open reduction and internal fixation.     

桡骨小头骨折的治疗

Objective To treat radial head fractures with open reduction and internal fixation, removal of the radial head and artificial joint replacement based on different fracture types to discuss the outcome of these methods and summarize optimal strategy for treatment of radial head fractures. Meth-ods A retrospective study was done on data of 47 patients with 48 radial head fractures treated in our de-partment from November 1999 to May 2008. Among them, nine patients were treated conservatively (all type Mason Ⅰ fractures), 28 treated with open reduction and internal fixation (one patient with type Ma-son Ⅰ fracture, 14 with type Mason Ⅱ and 13 with type Mason Ⅲ), eight with removal of radial head (three patients with type Mason Ⅲ fractures and five with type Ⅳ) and three with artificial joint replace-ment (all type Mason Ⅳ fractures). Results All patients were followed up for average 2.8 years (1-4.4 years). Two patients treated with artificial joint replacement were followed up for six months and three months respectively. According to the Mayo Elbow Performance Index, the excellence rate was 8/9 in conservative treatment, 82% (23/28) in open reduction and internal fixation, 6/8 in removal of the radial head and 3/3 in artificial joint replacement respectively. Conclusions The radial head fracture should be given anatomical reduction for early functional exercise. Conservative treatment can be used for type Mason Ⅰ fractures, open reduction and internal fixation for type Mason Ⅱ , type Mason Ⅲ fractures and part of type Mason Ⅳ fractures. The removal of radial head or mental prosthesis replacement are al-ternative for parte of type Mason Ⅳ fractures that can not attain stable fixation through open reduction and internal fixation.     

桡骨小头骨折的治疗

Objective To treat radial head fractures with open reduction and internal fixation, removal of the radial head and artificial joint replacement based on different fracture types to discuss the outcome of these methods and summarize optimal strategy for treatment of radial head fractures. Meth-ods A retrospective study was done on data of 47 patients with 48 radial head fractures treated in our de-partment from November 1999 to May 2008. Among them, nine patients were treated conservatively (all type Mason Ⅰ fractures), 28 treated with open reduction and internal fixation (one patient with type Ma-son Ⅰ fracture, 14 with type Mason Ⅱ and 13 with type Mason Ⅲ), eight with removal of radial head (three patients with type Mason Ⅲ fractures and five with type Ⅳ) and three with artificial joint replace-ment (all type Mason Ⅳ fractures). Results All patients were followed up for average 2.8 years (1-4.4 years). Two patients treated with artificial joint replacement were followed up for six months and three months respectively. According to the Mayo Elbow Performance Index, the excellence rate was 8/9 in conservative treatment, 82% (23/28) in open reduction and internal fixation, 6/8 in removal of the radial head and 3/3 in artificial joint replacement respectively. Conclusions The radial head fracture should be given anatomical reduction for early functional exercise. Conservative treatment can be used for type Mason Ⅰ fractures, open reduction and internal fixation for type Mason Ⅱ , type Mason Ⅲ fractures and part of type Mason Ⅳ fractures. The removal of radial head or mental prosthesis replacement are al-ternative for parte of type Mason Ⅳ fractures that can not attain stable fixation through open reduction and internal fixation.     

桡骨小头骨折的治疗

Objective To treat radial head fractures with open reduction and internal fixation, removal of the radial head and artificial joint replacement based on different fracture types to discuss the outcome of these methods and summarize optimal strategy for treatment of radial head fractures. Meth-ods A retrospective study was done on data of 47 patients with 48 radial head fractures treated in our de-partment from November 1999 to May 2008. Among them, nine patients were treated conservatively (all type Mason Ⅰ fractures), 28 treated with open reduction and internal fixation (one patient with type Ma-son Ⅰ fracture, 14 with type Mason Ⅱ and 13 with type Mason Ⅲ), eight with removal of radial head (three patients with type Mason Ⅲ fractures and five with type Ⅳ) and three with artificial joint replace-ment (all type Mason Ⅳ fractures). Results All patients were followed up for average 2.8 years (1-4.4 years). Two patients treated with artificial joint replacement were followed up for six months and three months respectively. According to the Mayo Elbow Performance Index, the excellence rate was 8/9 in conservative treatment, 82% (23/28) in open reduction and internal fixation, 6/8 in removal of the radial head and 3/3 in artificial joint replacement respectively. Conclusions The radial head fracture should be given anatomical reduction for early functional exercise. Conservative treatment can be used for type Mason Ⅰ fractures, open reduction and internal fixation for type Mason Ⅱ , type Mason Ⅲ fractures and part of type Mason Ⅳ fractures. The removal of radial head or mental prosthesis replacement are al-ternative for parte of type Mason Ⅳ fractures that can not attain stable fixation through open reduction and internal fixation.     

桡骨小头骨折的治疗

Objective To treat radial head fractures with open reduction and internal fixation, removal of the radial head and artificial joint replacement based on different fracture types to discuss the outcome of these methods and summarize optimal strategy for treatment of radial head fractures. Meth-ods A retrospective study was done on data of 47 patients with 48 radial head fractures treated in our de-partment from November 1999 to May 2008. Among them, nine patients were treated conservatively (all type Mason Ⅰ fractures), 28 treated with open reduction and internal fixation (one patient with type Ma-son Ⅰ fracture, 14 with type Mason Ⅱ and 13 with type Mason Ⅲ), eight with removal of radial head (three patients with type Mason Ⅲ fractures and five with type Ⅳ) and three with artificial joint replace-ment (all type Mason Ⅳ fractures). Results All patients were followed up for average 2.8 years (1-4.4 years). Two patients treated with artificial joint replacement were followed up for six months and three months respectively. According to the Mayo Elbow Performance Index, the excellence rate was 8/9 in conservative treatment, 82% (23/28) in open reduction and internal fixation, 6/8 in removal of the radial head and 3/3 in artificial joint replacement respectively. Conclusions The radial head fracture should be given anatomical reduction for early functional exercise. Conservative treatment can be used for type Mason Ⅰ fractures, open reduction and internal fixation for type Mason Ⅱ , type Mason Ⅲ fractures and part of type Mason Ⅳ fractures. The removal of radial head or mental prosthesis replacement are al-ternative for parte of type Mason Ⅳ fractures that can not attain stable fixation through open reduction and internal fixation.     

桡骨小头骨折的治疗

Objective To treat radial head fractures with open reduction and internal fixation, removal of the radial head and artificial joint replacement based on different fracture types to discuss the outcome of these methods and summarize optimal strategy for treatment of radial head fractures. Meth-ods A retrospective study was done on data of 47 patients with 48 radial head fractures treated in our de-partment from November 1999 to May 2008. Among them, nine patients were treated conservatively (all type Mason Ⅰ fractures), 28 treated with open reduction and internal fixation (one patient with type Ma-son Ⅰ fracture, 14 with type Mason Ⅱ and 13 with type Mason Ⅲ), eight with removal of radial head (three patients with type Mason Ⅲ fractures and five with type Ⅳ) and three with artificial joint replace-ment (all type Mason Ⅳ fractures). Results All patients were followed up for average 2.8 years (1-4.4 years). Two patients treated with artificial joint replacement were followed up for six months and three months respectively. According to the Mayo Elbow Performance Index, the excellence rate was 8/9 in conservative treatment, 82% (23/28) in open reduction and internal fixation, 6/8 in removal of the radial head and 3/3 in artificial joint replacement respectively. Conclusions The radial head fracture should be given anatomical reduction for early functional exercise. Conservative treatment can be used for type Mason Ⅰ fractures, open reduction and internal fixation for type Mason Ⅱ , type Mason Ⅲ fractures and part of type Mason Ⅳ fractures. The removal of radial head or mental prosthesis replacement are al-ternative for parte of type Mason Ⅳ fractures that can not attain stable fixation through open reduction and internal fixation.     

桡骨小头骨折的治疗

Objective To treat radial head fractures with open reduction and internal fixation, removal of the radial head and artificial joint replacement based on different fracture types to discuss the outcome of these methods and summarize optimal strategy for treatment of radial head fractures. Meth-ods A retrospective study was done on data of 47 patients with 48 radial head fractures treated in our de-partment from November 1999 to May 2008. Among them, nine patients were treated conservatively (all type Mason Ⅰ fractures), 28 treated with open reduction and internal fixation (one patient with type Ma-son Ⅰ fracture, 14 with type Mason Ⅱ and 13 with type Mason Ⅲ), eight with removal of radial head (three patients with type Mason Ⅲ fractures and five with type Ⅳ) and three with artificial joint replace-ment (all type Mason Ⅳ fractures). Results All patients were followed up for average 2.8 years (1-4.4 years). Two patients treated with artificial joint replacement were followed up for six months and three months respectively. According to the Mayo Elbow Performance Index, the excellence rate was 8/9 in conservative treatment, 82% (23/28) in open reduction and internal fixation, 6/8 in removal of the radial head and 3/3 in artificial joint replacement respectively. Conclusions The radial head fracture should be given anatomical reduction for early functional exercise. Conservative treatment can be used for type Mason Ⅰ fractures, open reduction and internal fixation for type Mason Ⅱ , type Mason Ⅲ fractures and part of type Mason Ⅳ fractures. The removal of radial head or mental prosthesis replacement are al-ternative for parte of type Mason Ⅳ fractures that can not attain stable fixation through open reduction and internal fixation.     

桡骨小头骨折的治疗

Objective To treat radial head fractures with open reduction and internal fixation, removal of the radial head and artificial joint replacement based on different fracture types to discuss the outcome of these methods and summarize optimal strategy for treatment of radial head fractures. Meth-ods A retrospective study was done on data of 47 patients with 48 radial head fractures treated in our de-partment from November 1999 to May 2008. Among them, nine patients were treated conservatively (all type Mason Ⅰ fractures), 28 treated with open reduction and internal fixation (one patient with type Ma-son Ⅰ fracture, 14 with type Mason Ⅱ and 13 with type Mason Ⅲ), eight with removal of radial head (three patients with type Mason Ⅲ fractures and five with type Ⅳ) and three with artificial joint replace-ment (all type Mason Ⅳ fractures). Results All patients were followed up for average 2.8 years (1-4.4 years). Two patients treated with artificial joint replacement were followed up for six months and three months respectively. According to the Mayo Elbow Performance Index, the excellence rate was 8/9 in conservative treatment, 82% (23/28) in open reduction and internal fixation, 6/8 in removal of the radial head and 3/3 in artificial joint replacement respectively. Conclusions The radial head fracture should be given anatomical reduction for early functional exercise. Conservative treatment can be used for type Mason Ⅰ fractures, open reduction and internal fixation for type Mason Ⅱ , type Mason Ⅲ fractures and part of type Mason Ⅳ fractures. The removal of radial head or mental prosthesis replacement are al-ternative for parte of type Mason Ⅳ fractures that can not attain stable fixation through open reduction and internal fixation.     

Motion artifact reduction with fast spin-echo imaging

The influence of signal averaging (n), repetition time (TR), and echo delay (TE) on systematic noise (cardiac, vascular, respiratory, and peristaltic ghost artifacts) and statistical noise (thermal effects) was determined in eight healthy volunteers and 57 patients. Systematic noise was the dominant factor degrading abdominal magnetic resonance (MR) images. Signal averaging was the primary determinant of both statistical and systematic image noise, fitting a power function (n)b with b = 0.44 and -0.42, respectively, close to the expected b = -0.5 power function. All types of ghosting showed the same sensitivity to signal averaging. Normalized systematic noise increased slightly with TR (b = 0.16) and increased markedly with TE (b = 0.40). These data indicate that the short TR, short TE technique is a powerful method for reducing motion artifacts on breathhold images and can be combined with signal averaging to further suppress artifacts, improve signal-to-noise ratio, and maximize anatomic resolution.     

Radiation dose reduction in hepatic multidetector computed tomography with a novel adaptive noise reduction filter

Purpose The aim of this study was to optimize a novel adaptive noise reduction filter based on patient body weight and to investigate its utility for improving the image quality of low-dose hepatic computed tomography (CT) scans. Materials and methods The tube current-time product was changed from 140 to 180 and from 60 to 100 mAs at standard-and low-dose CT, respectively, based on the body weights of 45 patients. Unenhanced and two-phase contrast-enhanced helical scans were obtained at the standard dose during the hepatic arterial and equilibrium phases. During the equilibrium phase, we obtained low-dose scans of the liver immediately after standard-dose scans. The low-dose CT images were postprocessed with the filter. Two radiologists visually evaluated artifacts in the liver parenchyma and its graininess, the sharpness of the liver contour, tumor conspicuity, homogeneity of the enhancement of the portal vein, and overall image quality. Results There was no statistically significant difference between standard and filtered low-dose images with respect to artifacts in the liver, the graininess of the liver parenchyma, tumor conspicuity, homogeneity of enhancement of the portal vein, or overall image quality. Conclusion The adaptive noise reduction filter effectively reduced image noise. We confirmed the effectiveness of the filter by examining clinical hepatic images obtained at low-dose CT.     

Metal artefact reduction in gemstone spectral imaging dual-energy CT with and without metal artefact reduction software

Objective

To assess the usefulness of gemstone spectral imaging (GSI) dual-energy CT (DECT) with/without metal artefact reduction software (MARs).

Methods

The DECTs were performed using fast kV-switching GSI between 80 and 140 kV. The CT data were retro-reconstructed with/without MARs, by different displayed fields-of-view (DFOV), and with synthesised monochromatic energy in the range 40–140 keV. A phantom study of size and CT numbers was performed in a titanium plate and a stainless steel plate. A clinical study was performed in 26 patients with metallic hardware. All images were retrospectively reviewed in terms of the visualisation of periprosthetic regions and the severity of beam-hardening artefacts by using a five-point scale.

Results

The GSI-MARs reconstruction can markedly reduce the metal-related artefacts, and the image quality was affected by the prosthesis composition and DFOV. The spectral CT numbers of the prosthesis and periprosthetic regions showed different patterns on stainless steel and titanium plates.

Conclusion

Dual-energy CT with GSI-MARs can reduce metal-related artefacts and improve the delineation of the prosthesis and periprosthetic region. We should be cautious when using GSI-MARs because the image quality was affected by the prosthesis composition, energy (in keV) and DFOV. The metallic composition and size should be considered in metallic imaging with GSI-MARs reconstruction.

Key Points

• Metal-related artefacts can be troublesome on musculoskeletal computed tomography (CT).

• Gemstone spectral imaging (GSI) with dual-energy CT (DECT) offers a novel solution

• GSI and metallic artefact reduction software (GSI-MAR) can markedly reduce these artefacts.

• However image quality is influenced by the prosthesis composition and other parameters.

• We should be aware about potential overcorrection when using GSI-MARs.

     

TIPS reduction with use of stents or stent-grafts

This report describes new techniques to perform TIPS reduction in patients with post-TIPS complications. Methods included hourglass-shaped stents and stent-grafts, and parallel stents and stent-grafts. All procedures were technically successful, resulting in increased portosystemic gradients and decreased symptoms, although patient outcomes were mixed. None of the patients experienced recurrent variceal hemorrhage or ascites in short-term follow-up. Stent-grafts have the advantage of immediate exclusion of blood flow outside the reducing stent, resulting in an immediate reduction of the caliber of the shunt. Techniques that allow fine adjustment of shunt diameters may have further advantages.     

Noise-based tube current reduction method with iterative reconstruction for reduction of radiation exposure in coronary CT angiography

Purpose

To investigate the potential of noise-based tube current reduction method with iterative reconstruction to reduce radiation exposure while achieving consistent image quality in coronary CT angiography (CCTA).

Materials and methods

294 patients underwent CCTA on a 64-detector row CT equipped with iterative reconstruction. 102 patients with fixed tube current were assigned to Group 1, which was used to establish noise-based tube current modulation formulas, where tube current was modulated by the noise of test bolus image. 192 patients with noise-based tube current were randomly assigned to Group 2 and Group 3. Filtered back projection was applied for Group 2 and iterative reconstruction for Group 3. Qualitative image quality was assessed with a 5 point score. Image noise, signal intensity, volume CT dose index, and dose-length product were measured.

Results

The noise-based tube current modulation formulas were established through regression analysis using image noise measurements in Group 1. Image noise was precisely maintained at the target value of 35.00 HU with small interquartile ranges for Group 2 (34.17–35.08 HU) and Group 3 (34.34–35.03 HU), while it was from 28.41 to 36.49 HU for Group 1. All images in the three groups were acceptable for diagnosis. A relative 14% and 41% reduction in effective dose for Group 2 and Group 3 were observed compared with Group 1.

Conclusion

Adequate image quality could be maintained at a desired and consistent noise level with overall 14% dose reduction using noise-based tube current reduction method. The use of iterative reconstruction further achieved approximately 40% reduction in effective dose.     

Noise reduction in MR angiography with nonlinear anisotropic filtering

PURPOSE: To evaluate three-dimensional nonlinear anisotropic filtering in suppressing image noise in high spatial resolution magnetic resonance angiograms (MRA) acquired with hybrid undersampled projection reconstruction and phase contrast vastly undersampled isotropic projection reconstruction (PC-VIPR). MATERIALS AND METHODS: Three-dimensional nonlinear anisotropic filtering was quantitatively analyzed and evaluated through the measurement of contrast to noise ratio (CNR) in PC-VIPR images and contrast enhanced peripheral MRA images. To filter MRA images with ultra-high spatial resolution and poor CNR, a spatial frequency dependent nonlinear anisotropic filtering algorithm was proposed that uses two-step processing to filter the whole spatial frequency data. RESULTS: Three-dimensional nonlinear anisotropic filtering was shown to be effective in suppressing noise and improving CNR in MRA with isotropic spatial resolution. Higher CNR was achieved using spatial frequency dependent nonlinear anisotropic filtering. A typical CNR gain of between 50-100% was shown in our studies. CONCLUSION: Three-dimensional nonlinear anisotropic filtering significantly improved CNR in MRA images with isotropic spatial resolution. Spatial frequency dependent nonlinear anisotropic filtering further improved CNR for MRA images with ultra-high spatial resolution and low CNR.     

Motion artifact reduction with three-point ghost phase cancellation.

A novel method for "ghost" artifact suppression is introduced. It suppresses ghosts induced by motion in any direction, as well as other types of quasi-periodic signal modulation. Because it requires neither special hardware nor intensive data processing, it can be easily implemented on conventional magnetic resonance (MR) imagers. The method is based on the concept of decomposition of a ghosted complex image into a ghost mask and ideal image. A set of deliberately designed acquisitions are used to generate a set of ghosted complex images in which the ghost components are related in a simple manner. With use of equations describing image decomposition and ghost correlation, the ideal image can be calculated pixel by pixel. The ideal image obtained (representing the time-averaged spin-density distribution) is shown to be a truer representation of physical reality than the ghost-free image obtained with ordered phase encoding. In this technique, both interview and intraview effects are taken into account. The technique is also useful in simultaneously suppressing ghosts from multifrequency signal modulations such as respiratory and cardiac motions. The method was successfully tested with three time-interleaved, phase-encoding-order-shifted acquisitions. Experimental results have shown that it is a simple but effective technique.     

Slice encoding for metal artifact correction with noise reduction

Magnetic resonance imaging (MRI) near metallic implants is often hampered by severe metal artifacts. To obtain distortion‐free MR images near metallic implants, SEMAC (Slice Encoding for Metal Artifact Correction) corrects metal artifacts via robust encoding of excited slices against metal‐induced field inhomogeneities, followed by combining the data resolved from multiple SEMAC‐encoded slices. However, as many of the resolved data elements only contain noise, SEMAC‐corrected images can suffer from relatively low signal‐to‐noise ratio. Improving the signal‐to‐noise ratio of SEMAC‐corrected images is essential to enable SEMAC in routine clinical studies. In this work, a new reconstruction procedure is proposed to reduce noise in SEMAC‐corrected images. A singular value decomposition denoising step is first applied to suppress quadrature noise in multi‐coil SEMAC‐encoded slices. Subsequently, the singular value decomposition‐denoised data are selectively included in the correction of through‐plane distortions. The experimental results demonstrate that the proposed reconstruction procedure significantly improves the SNR without compromising the correction of metal artifacts. Magn Reson Med, 2011. © 2011 Wiley‐Liss, Inc.