Till Örebro universitet

PURPOSE: The purpose of this study was to assess the long-term clinical, subjective, and radiographic results of pyrocarbon hemiarthroplasty for proximal interphalangeal joint (PIPJ) arthritis at a single institution.

METHODS: Patients treated with a pyrolytic carbon hemiarthroplasty between 2005 and 2015 were contacted for a clinical follow-up visit. Patients were assessed before surgery, one year after surgery, and again after a mean of 11 years (range: 6-16 years). Objective outcomes were assessed with grip strength, pinch strength, and range of motion (ROM). Subjective outcomes were assessed by the Disabilities of the Arm, Shoulder, and Hand score, Canadian Occupational Performance Measure (performance and satisfaction), and Visual Analog Scale pain scores at rest and during activity. Radiographic assessments were completed according to Sweets and Stern as modified by Wagner et al.

RESULTS: A total of 68 fingers in 52 patients underwent PIPJ hemiarthroplasty. Thirty-six arthroplasties in 29 patients were available for the long-term follow-up, five patients had died, and the remaining cases were contacted by phone. Three cases were lost to follow-up. Preoperative diagnoses included 41 fingers with osteoarthritis or posttraumatic arthritis, and 27 fingers with inflammatory arthritis. Eight cases had undergone revision at the time of follow-up, and the 10-year implant survival was 72%. The revisions were performed after a mean of two years after surgery. Three patients had undergone soft-tissue procedures. Visual Analog Scale pain scores, Disabilities of the Arm, Shoulder, and Hand scores, and Canadian Occupational Performance Measure scores improved significantly compared with that before surgery. Grip strength and pinch grip remained unchanged. However, PIPJ ROM deteriorated significantly one year after surgery, when compared with that before surgery.

CONCLUSIONS: Pyrocarbon hemiarthroplasty of the PIPJ has an acceptable long-term implant survival, and the significant improvement in pain scores and patient-reported outcomes is maintained over time. Pyrocarbon hemiarthroplasty could be a viable option in the management of PIPJ arthritis. Patients should be advised that PIPJ ROM deteriorates over time.

TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

BACKGROUND: Magnetic resonance imaging (MRI) is useful in the diagnosis of clinically significant prostate cancer (csPCa). MRI-derived radiomics may support the diagnosis of csPCa. PURPOSE: To investigate whether adding radiomics from biparametric MRI to predictive models based on clinical and MRI parameters improves the prediction of csPCa in a multisite-multivendor setting.

MATERIAL AND METHODS: Clinical information (PSA, PSA density, prostate volume, and age), MRI reviews (PI-RADS 2.1), and radiomics (histogram and texture features) were retrieved from prospectively included patients examined at different radiology departments and with different MRI systems, followed by MRI-ultrasound fusion guided biopsies of lesions PI-RADS 3-5. Predictive logistic regression models of csPCa (Gleason score ≥7) for the peripheral (PZ) and transition zone (TZ), including clinical data and PI-RADS only, and combined with radiomics, were built and compared using receiver operating characteristic (ROC) curves.

RESULTS: In total, 456 lesions in 350 patients were analyzed. In PZ and TZ, PI-RADS 4-5 and PSA density, and age in PZ, were independent predictors of csPCa in models without radiomics. In models including radiomics, PI-RADS 4-5, PSA density, age, and ADC energy were independent predictors in PZ, and PI-RADS 5, PSA density and ADC mean in TZ. Comparison of areas under the ROC curve (AUC) for the models without radiomics (PZ: AUC = 0.82, TZ: AUC = 0.80) versus with radiomics (PZ: AUC = 0.82, TZ: AUC = 0.82) showed no significant differences (PZ: P = 0.366; TZ: P = 0.171).

CONCLUSION: PSA density and PI-RADS are potent predictors of csPCa. Radiomics do not add significant information to our multisite-multivendor dataset.

BACKGROUND: Volar locking plate fixation is the most common method of operative fixation of distal radius fractures (DRFs). For more complex cases, combined plating is an option for stabilizing intra-articular fragments. The prevalence of posttraumatic arthritis (PA) after an intra-articular DRF, and its relation to patient-reported outcome measures (PROMs), remains unclear. The purpose of this study was to study the prevalence of PA and its correlation to clinical outcome measures.

METHODS: We evaluated 97 consecutive patients with intra-articular DRF, operated with combined plating, 7 years postoperatively. The primary outcome measure was the prevalence of radiographic PA. Secondary outcome measures included visual analog scale (VAS) pain score, hand grip strength, wrist range of motion (ROM), Patient-Rated Wrist Evaluation (PRWE) score, and Quick Disabilities of the Arm, Shoulder, and Hand (QuickDASH) score. Radiographic examination was performed between 1 and 7 years postoperatively.

RESULTS: The prevalence of PA was 29% at the 7-year follow-up. No correlation was found between PA and ROM, hand grip strength, PRWE, QuickDASH, VAS pain scores, or radiographic reduction. Median wrist ROM and grip strength were significantly inferior compared with the uninjured side. Hardware removal was performed in 51.5% of cases. There were 2 cases of tendon ruptures.

CONCLUSIONS: Combined plating can yield a good clinical outcome 7 years postoperatively and a low prevalence of PA. The presence of PA did not correlate to clinical outcome measures or to the accuracy of anatomical reduction 1 year postoperatively. The frequency of tendon ruptures was acceptable, but the high frequency of hardware removal is a concern.

OBJECTIVES: To compare the assessment of patients with multiple sclerosis (MS) using synthetic and conventional MRI.

MATERIALS AND METHODS: Synthetic and conventional axial images were prospectively acquired for 52 patients with diagnosed MS. Quantitative MRI (qMRI) was used for measuring proton density and relaxation times (T1, T2) and then, based on these parameters, synthetic T1W, T2W and FLAIR images were calculated. Image stacks were reviewed blindly, independently and in random order by two radiologists. The number and location for all lesions were documented and categorised. A combined report of lesion load and presence of contrast-enhancing lesions was compiled for each patient. Agreement was evaluated using kappa statistic.

RESULTS: There was no significant difference in lesion detection using synthetic and conventional MRI in any anatomical region or for any of the three image types. Inter- and intra-observer agreements were mainly higher (p < 0.05) using conventional images but there was no significant difference in any specific region or for any image type. There was no significant difference in the outcome of the combined reports.

CONCLUSION: Synthetic MR images show potential to be used in the assessment of MS dissemination in space (DIS) despite a slightly lower inter- and intra-observer agreement compared to conventional MRI.

KEY POINTS:

• Synthetic MR images may potentially be useful in the assessment of MS.

• Examination times may be shortened.

• Inter- and intra-observer agreement is generally higher using conventional MRI.

Background: Iterative reconstruction (IR) is a recent reconstruction algorithm for computed tomography (CT) that can be used instead of the standard algorithm, filtered back projection (FBP), to reduce radiation dose and/or improve image quality.

Purpose: To evaluate and compare the image quality of low-dose CT of the lumbar spine reconstructed with IR to conventional FBP, without further reduction of radiation dose.

Material and Methods: Low-dose CT on 55 patients was performed on a Siemens scanner using 120 kV tube voltage, 30 reference mAs, and automatic dose modulation. From raw CT data, lumbar spine CT images were reconstructed with a medium filter (B41f) using FBP and four levels of IR (levels 2-5). Five reviewers scored all images on seven image quality criteria according to the European guidelines on quality criteria for CT, using a five-grade scale. A side-by-side comparison was also performed.

Results: There was significant improvement in image quality for IR (levels 2-4) compared to FBP. According to visual grading regression, odds ratios of all criteria with 95% confidence intervals for IR2, IR3, IR4, and IR5 were: 1.59 (1.39-1.83), 1.74 (1.51-1.99), 1.68 (1.46-1.93), and 1.08 (0.94-1.23), respectively. In the side-by-side comparison of all reconstructions, images with IR (levels 2-4) received the highest scores. The mean overall CTDIvol was 1.70 mGy (SD 0.46; range, 1.01-3.83 mGy). Image noise decreased in a linear fashion with increased strength of IR.

Conclusion: Iterative reconstruction at levels 2, 3, and 4 improves image quality of low-dose CT of the lumbar spine compared to FPB.

Background: Lumbar spine radiography is often performed instead of CT for radiation dose concerns.

Purpose: To compare image quality and diagnostic information from low dose lumbar spine CT at an effective dose of about 1 mSv with lumbar spine radiography.

Material and Methods: Fifty-one patients were examined by both methods. Five reviewers scored all examinations on eight image quality criteria using a five-graded scale and also assessed three common pathologic changes.

Results: Low dose CT scored better than radiography on the following: sharp reproduction of disc profile and vertebral end-plates (odds ratio [OR], 1.8; 95% confidence interval [CI], 1.3-2.5), intervertebral foramina and pedicles (OR, 4.3; 95% CI, 3.1-5.9), intervertebral joints (OR, 139; 95% CI, 59-326), spinous and transverse processes (OR, 7.0; 95% CI, 4.3-11.2), sacro-iliac joints (OR, 4.2; 95% CI, 3.2-5.7), reproduction of the adjacent soft tissues (OR, 2.9; 95% CI, 2.1-4.0), and absence of any obscuring superimposed gastrointestinal gas and contents (OR, 188; 95% CI, 66-539). Radiography scored better on sharp reproduction of cortical and trabecular bone (OR, 0.3; 95% CI, 0.2-0.4). The reviewers visualized disk degeneration, spondylosis/diffuse idiopathic skeletal hyperostosis (DISH) and intervertebral joint osteoarthritis more clearly and were more certain with low dose CT. Mean time to review low dose CT was 204 s (95% CI, 194-214 s.), radiography 152 s (95% CI, 146-158 s.). The effective dose for low dose CT was 1.0-1.1 mSv, for radiography 0.7 mSv.

Conclusion: Low dose lumbar spine CT at about 1 mSv has superior image quality to lumbar spine radiography with more anatomical and diagnostic information.

Objective: To describe the effects of switching treatment from ongoing first-line injectable therapies to rituximab on inflammatory activity measured by MRI and levels of CSF neurofilament light chain (CSF-NFL) in a cohort of patients with clinically stable relapsing-remitting multiple sclerosis (RRMS).

Method: Seventy-five patients with clinically stable RRMS treated with the first-line injectables interferon-β (IFN-β) and glatiramer acetate (GA) at 3 Swedish centers were switched to rituximab in this open-label phase II multicenter study. After a run-in period of 3 months, 2 IV doses of 1,000 mg rituximab were given 2 weeks apart followed by repeated clinical assessment, MRI, and CSF-NFL for 24 months.

Results: The mean cumulated number of gadolinium-enhancing lesions per patient at months 3 and 6 after treatment shift to rituximab was reduced compared to the run-in period (0.028 vs 0.36, p = 0.029). During the first year after treatment shift, the mean number of new or enlarged T2 lesions per patient was reduced (0.01 vs 0.28, p = 0.004) and mean CSF-NFL levels were reduced by 21% (p = 0.01).

Conclusions: For patients with RRMS, a treatment switch from IFN or GA to rituximab is associated with reduced inflammatory activity measured by MRI and CSF-NFL.

Classification of evidence: This study provides Class IV evidence that rituximab has an equal or superior effect in reducing inflammatory activity in RRMS measured by MRI and CSF-NFL compared to first-line injectables during the first year after treatment shift.

Objectives: To evaluate metal artefact reduction (MAR) techniques from four computed tomography (CT) vendors in hip prosthesis imaging.

Methods: Bilateral hip prosthesis phantom images, obtained by using MAR algorithms for single energy CT data or dual energy CT (DECT) data and by monoenergetic reconstructions of DECT data, were visually graded by five radiologists using ten image quality criteria. Comparisons between the MAR images and a reference image were performed for each scanner separately. Ordinal probit regression analysis was used.

Results: The MAR algorithms in general improved the image quality based on the majority of the criteria (up to between 8/10 and 10/10) with a statistically improvement in overall image quality (P<0.001). However, degradation of image quality, such as new artefacts, was seen in some cases. A few monoenergetic reconstruction series improved the image quality (P<0.004) for one of the DECT scanners, but it was only improved for some of the criteria (up to 5/10). Monoenergetic reconstructions resulted in worse image quality for the majority of the criteria (up to 7/10) for the other DECT scanner.

Conclusions: The MAR algorithms improved the image quality of the hip prosthesis CT images. However, since additional artefacts and degradation of image quality were seen in some cases, all algorithms should be carefully evaluated for every clinical situation. Monoenergetic reconstructions were in general concluded to be insufficient for reducing metal artifacts. Advances in knowledge: Qualitative evaluation of the usefulness of several MAR techniques from different vendors in CT imaging of hip prosthesis.

Purpose: To evaluate the accuracy and reproducibility of a quantitative magnetic resonance (qMR) imaging method (QRAPMASTER) for simultaneous measurements of T1 and T2 relaxation times, and proton density (PD).

Materials and Methods: Measurements of T1, T2, and PD with qMR were performed using phantoms with different relaxation times and concentrations of heavy water. Healthy volunteers were examined with different head coils. Regional measurements were performed in normal-appearing white and gray matter from the healthy control subjects, and in multiple sclerosis (MS) patients.

Results: In phantom measurements, QRAPMASTER slightly underestimated T1, and T2 variations between repeated measurements were modest. PD was generally overestimated. The overall relative difference was 1.2 5.3% (T1), 6.6 1.9% (12), and 0.7 5.1% (PD). In healthy volunteers, there were no statistically significant differences of T1, T2 or PD using different head coils. Values of T1, T2, and PD obtained in healthy controls and MS patients were within reference ranges. However, significant differences were found in normal-appearing gray and white matter.

Conclusion: QRAPMASTER can be considered a sufficiently accurate and reproducible method for use in clinical practice. Neuropathology in normal-appearing brain tissue may be revealed using this MR method, with putative implications for quantification of tissue damage in neurological diseases. (C) 2015 Elsevier Inc. All rights reserved.

Partial segmental thrombosis of the corpus cavernosum (PSTCC) is a rare urological condition characterized by a painful, firm mass in the proximal part of the corpus cavernosum. The underlying pathophysiology of this condition is not fully understood. We present a case diagnosed by magnetic resonance imaging with complete clinical recovery after conservative treatment and novel associated findings, such as excessive alcohol intake. We also review the previous cases of PSTCC and propose a two hit model explaining PSTCC's etiology. UROLOGY 79: 708-712, 2012.