Retrospective evaluation of radiological and clinical outcomes after surgical treatment of proximal femoral fractures utilizing PFNA and PFNA augmented.

INTRODUCTION: The primary aim of this study was to evaluate the clinical and radiological outcomes after surgical treatment of proximal femoral fractures utilizing the Proximal Femoral Nail Antirotation (PFNA), with the main focus on complications and reoperations. The secondary aim was to compare the outcomes of patients with and without cement augmentation of the cephalomedullary nails. MATERIALS AND METHODS: All patients with an acute proximal femoral fracture consequently treated with a PFNA between January 2011 and Dezember  2018 were evaluated. Clinical and radiological data were assessed for intra- and postoperative complications, including treatment failure. In addition, intra- and postoperative radiographs were used to determine the position of the implant, and any migration, via Tip-Apex-Distance (TAD) and the caput-collum-diaphyseal angle (CCD). The accuracy of the fracture reduction was rated according to Baumgaertners criteria. RESULTS: Two hundred sixty-four consecutive patients (mean age 78.8 ± 12.0; 73.1% female) were included. The predominant OTA/AO fracture classification was 31A1 (153 cases, 58.0%). The average duration of surgery was 63.1 ± 28.0 min and showed no significant differences between PFNA and PFNA with augmentation. The implant positioning was rated as good in 222 cases (84.1%). Two hundred sixty-three patients (99.6%) showed evidence of healing within the time frame of three months postoperatively, one case of delayed union healed after secondary dynamization. During the observational period, 18 patients (6.8%) required a total of 23 additional surgeries. Overall, a lower reoperation rate was observed following the use of the augmentation option (2/86 patients (2.3%) vs. 16/178 patients (9.0%), p = 0.04). In particular, there were no cases of cut-out or cut-through among patients who underwent augmentation as part of osteosynthesis. CONCLUSIONS: Overall reoperation rate after surgical treatment of proximal femoral fractures utilizing the Proximal Femoral Nail Antirotation (PFNA) was 6.8%, with 23 additional surgeries performed in 18 patients. The usage of the PFNA with augmentation showed equally good implant positioning, excellent healing rates and fewer postoperative complications compared to the PFNA implant alone with a similar overall duration of surgery.

Can we identify abnormal pelvic tilt using pre-THA anteroposterior pelvic radiographs?

BACKGROUND: Patients with increased pelvic tilt (PT) are at risk for instability following total hip arthroplasty (THA). Identification of increased PT using anteroposterior (AP) pelvic radiographs could avoid additional spinopelvic radiographs. This study aimed to (1) describe which AP pelvic parameters most accurately estimate sagittal PT, and (2) determine thresholds for these parameters that can identify patients with increased PT. METHODS: This was a retrospective, consecutive, cohort study in a tertiary referral hospital on 225 patients (age: 66 ± 12 years-old; 52% female) listed for THA. Patients underwent pre-operative standing AP pelvic radiographs to measure distance- and angular- based parameters from several anatomical landmarks. Sagittal PT was measured on a standing lateral spinopelvic radiograph and considered high when ≥ 20°. RESULTS: No AP pelvic parameters correlated strongly with sagittal PT. Ratio between horizontal and vertical diameter of the pelvic foramen (C/D ratio) (rho - 0.341; p < 0.001); and vertical distance between trans-SIJ and trans-ASIS line (SITA) (rho 0.307; p < 0.001) correlated moderately with sagittal PT. Sacro-femoral-pubic (SFP) angle < 60° had highest sensitivity (85%), but lowest specificity (52%) to differentiate between patients with and without increased PT. If SITA > 62 mm, C/D ratio < 0.5 and SFP < 60°, specificity increased (88%), but sensitivity was low (49%). CONCLUSION: In the absence of computerized models, AP pelvic parameters cannot accurately predict sagittal PT. However, an SFP < 60° should alert a hip surgeon that a patient may have an increased PT, and would benefit from additional lateral spinopelvic imaging prior to THA. LEVEL OF EVIDENCE: Level II, diagnostic study.

Treatment of cartilage defects in the patellofemoral joint with matrix-associated autologous chondrocyte implantation effectively improves pain, function, and radiological outcomes after 5-7 years.

INTRODUCTION: The aim of the present study was to evaluate midterm outcomes 5-7 years after matrix-associated autologous chondrocyte implantation (MACI) in the patellofemoral joint. MATERIALS AND METHODS: Twenty-six patients who had undergone MACI using the Novocart® 3D scaffold were prospectively evaluated. Clinical outcomes were determined by measuring the 36-Item Short-Form Health Survey (SF-36) and International Knee Documentation Committee (IKDC) scores and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) values preoperatively and 3, 6, and 12 months, and a mean of 6 years postoperatively. At the final follow-up, the Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) score was evaluated. RESULTS: Twenty-two patients with 23 focal cartilage defects (19 patella and four trochlea) were available for the final follow-up. The mean defect size was 4.0 ± 1.9 cm2 (range 2.4-9.4 cm2). All clinical outcome scores improved significantly until 5-7 years after MACI (SF-36 score, 61.2 ± 19.6 to 83.2 ± 11.6; P = 0.001; IKDC score, 47.5 ± 20.6 to 74.7 ± 15.5; P < 0.001; and WOMAC, 29.8 ± 15.7 to 8.2 ± 10.3; P < 0.001). The mean MOCART score was 76.0 ± 11.0 at the final follow-up. Nineteen of the 22 patients (86.4%) were satisfied with the outcomes after 5-7 years and responded that they would undergo the procedure again. CONCLUSION: MACI in the patellofemoral joint demonstrated good midterm clinical results with a significant reduction in pain, improvement in function, and high patient satisfaction. These clinical findings are supported by radiological evidence from MOCART scores. LEVEL OF EVIDENCE: IV-case series.

Hip arthroscopy with initial access to the peripheral compartment for femoroacetabular impingement: midterm results from a large-scale patient cohort.

BACKGROUND: Hip arthroscopy with initial access to the peripheral compartment could reduce the risk of iatrogenic injury to the labrum and cartilage; furthermore, it avoids the need for large capsulotomies with separate portals for peripheral and central (intra-articular) arthroscopy. Clinical results of the peripheral-compartment-first technique remain sparse, in contrast to those of conventional hip arthroscopy starting in the intra-articular central compartment. The purpose of this study was to assess outcome of hip arthroscopy with the peripheral-compartment-first technique, including complication rates, revision rates and patient-reported outcome scores. MATERIALS AND METHODS: This outcome study included 704 hips with femoroacetabular impingement. All arthroscopies were performed using the peripheral-compartment-first technique. A joint replacement registry and the institutional database were used to assess the revision and complication rates, while patient-reported outcome measures were used to assess functional outcomes and patient satisfaction. RESULTS: In total, 704 hips (615 patients) were followed up for a mean of 6.2 years (range 1 to 9 years). The mean age of the patients was 32.1 ± 9.2 years. During the follow-up period, 26 of 704 (3.7%) hips underwent total hip arthroplasty (THA) after a mean of 1.8 ± 1.2 years, and 18 of the 704 (2.6%) hips required revision hip arthroscopy after a mean of 1.2 ± 2.1 years. 9.8% of the hips had an unsatisfactory patient-reported outcome at final follow-up. CONCLUSIONS: The results for the peripheral-compartment-first technique were promising. We recommend a well-conducted randomized controlled clinical trial to guide future therapeutic recommendations regarding the most favorable hip arthroscopy technique. LEVEL OF EVIDENCE: Level IV, therapeutic study. TRIAL REGISTRATION: This study was registered at ClinicalTrials.gov (U.S. National Library of Medicine; ID: NCT05310240).

Can gadolinium contrast agents be replaced with saline for direct MR arthrography of the hip? A pilot study with arthroscopic comparison.

OBJECTIVE: To compare image quality and diagnostic performance of preoperative direct hip magnetic resonance arthrography (MRA) performed with gadolinium contrast agent and saline solution. METHODS: IRB-approved retrospective study of 140 age and sex-matched symptomatic patients with femoroacetabular impingement, who either underwent intra-articular injection of 15-20 mL gadopentetate dimeglumine (GBCA), 2.0 mmol/L ("GBCA-MRA" group, n = 70), or 0.9% saline solution ("Saline-MRA" group, n = 70) for preoperative hip MRA and subsequent hip arthroscopy. 1.5 T hip MRA was performed including leg traction. Two readers assessed image quality using a 5-point Likert scale (1-5, excellent-poor), labrum and femoroacetabular cartilage lesions. Arthroscopic diagnosis was used to calculate diagnostic accuracy which was compared between groups with Fisher's exact tests. Image quality was compared with the Mann-Whitney U tests. RESULTS: Mean age was 33 years ± 9, 21% female patients. Image quality was excellent (GBCA-MRA mean range, 1.1-1.3 vs 1.1-1.2 points for Saline-MRA) and not different between groups (all p > 0.05) except for image contrast which was lower for Saline-MRA group (GBCA-MRA 1.1 ± 0.4 vs Saline-MRA 1.8 ± 0.5; p < 0.001). Accuracy was high for both groups for reader 1/reader 2 for labrum (GBCA-MRA 94%/ 96% versus Saline-MRA 96%/93%; p > 0.999/p = 0.904) and acetabular (GBCA-MRA 86%/ 83% versus Saline-MRA 89%/87%; p = 0.902/p = 0.901) and femoral cartilage lesions (GBCA-MRA 97%/ 99% versus Saline-MRA 97%/97%; both p > 0.999). CONCLUSION: Diagnostic accuracy and image quality of Saline-MRA and GBCA-MRA is high in assessing chondrolabral lesions underlining the potential role of non-gadolinium-based hip MRA. KEY POINTS: • Image quality of Saline-MRA and GBCA-MRA was excellent for labrum, acetabular and femoral cartilage, ligamentum teres, and the capsule (all p > 0.18). • The overall image contrast was lower for Saline-MRA (Saline-MRA 1.8 ± 0.5 vs. GBCA-MRA 1.1 ± 0.4; p < 0.001). • Diagnostic accuracy was high for Saline-MRA and GBCA-MRA for labrum (96% vs. 94%; p > 0.999), acetabular cartilage damage (89% vs. 86%; p = 0.902), femoral cartilage damage (97% vs. 97%; p > 0.999), and extensive cartilage damage (97% vs. 93%; p = 0.904).

Are degenerative findings detected on traction MR arthrography of the hip associated with failure of arthroscopic femoroacetabular impingement surgery?

OBJECTIVES: To identify preoperative degenerative features on traction MR arthrography associated with failure after arthroscopic femoroacetabular impingement (FAI) surgery. METHODS: Retrospective study including 102 patients (107 hips) undergoing traction magnetic resonance arthrography (MRA) of the hip at 1.5 T and subsequent hip arthroscopic FAI surgery performed (01/2016 to 02/2020) with complete follow-up. Clinical outcomes were assessed using the International Hip Outcome Tool (iHOT-12) score. Clinical endpoint for failure was defined as an iHOT-12 of < 60 points or conversion to total hip arthroplasty. MR images were assessed by two radiologists for presence of 9 degenerative lesions including osseous, chondrolabral/ligamentum teres lesions. Uni- and multivariate Cox regression analysis was performed to assess the association between MRI findings and failure of FAI surgery. RESULTS: Of the 107 hips, 27 hips (25%) met at least one endpoint at a mean 3.7 ± 0.9 years follow-up. Osteophytic changes of femur or acetabulum (hazard ratio [HR] 2.5-5.0), acetabular cysts (HR 3.4) and extensive cartilage (HR 5.1) and labral damage (HR 5.5) > 2 h on the clockface were univariate risk factors (all p < 0.05) for failure. Three risk factors for failure were identified in multivariate analysis: Acetabular cartilage damage > 2 h on the clockface (HR 3.2, p = 0.01), central femoral osteophyte (HR 3.1, p = 0.02), and femoral cartilage damage with ligamentum teres damage (HR 3.0, p = 0.04). CONCLUSION: Joint damage detected by preoperative traction MRA is associated with failure 4 years following arthroscopic FAI surgery and yields promise in preoperative risk stratification. CLINICAL RELEVANCE STATEMENT: Evaluation of negative predictors on preoperative traction MR arthrography holds the potential to improve risk stratification based on the already present joint degeneration ahead of FAI surgery. KEY POINTS: • Osteophytes, acetabular cysts, and extensive chondrolabral damage are risk factors for failure of FAI surgery. • Extensive acetabular cartilage damage, central femoral osteophytes, and combined femoral cartilage and ligamentum teres damage represent independent negative predictors. • Survival rates following hip arthroscopy progressively decrease with increasing prevalence of these three degenerative findings.

Patients with combined pelvic and spinal injuries have worse clinical and operative outcomes than patients with isolated pelvic injuries analysis of the German Pelvic Registry.

BACKGROUND: Pelvic fractures are often associated with spine injury in polytrauma patients. This study aimed to determine whether concomitant spine injury influence the surgical outcome of pelvic fracture. METHODS: We performed a retrospective analysis of data of patients registered in the German Pelvic Registry between January 2003 and December 2017. Clinical characteristics, surgical parameters, and outcomes were compared between patients with isolated pelvic fracture (group A) and patients with pelvic fracture plus spine injury (group B). We also compared apart patients with isolated acetabular fracture (group C) versus patients with acetabular fracture plus spine injury (group D). RESULTS: Surgery for pelvic fracture was significantly more common in group B than in group A (38.3% vs. 36.6%; p = 0.0002), as also emergency pelvic stabilizations (9.5% vs. 6.7%; p < 0.0001). The mean time to emergency stabilization was longer in group B (137 ± 106 min vs. 113 ± 97 min; p < 0.0001), as well as the mean time until definitive stabilization of the pelvic fracture (7.3 ± 4 days vs. 5.4 ± 8.0 days; p = 0.147). The mean duration of treatment and the morbidity and mortality rates were all significantly higher in group B (p < 0.0001). Operation time was significantly shorter in group C than in group D (176 ± 81 min vs. 203 ± 119 min, p < 0.0001). Intraoperative blood loss was not significantly different between the two groups with acetabular injuries. Although preoperative acetabular fracture dislocation was slightly less common in group D, postoperative fracture dislocation was slightly more common. The distribution of Matta grades was significantly different between the two groups. Patients with isolated acetabular injuries were significantly less likely to have neurological deficit at discharge (94.5%; p < 0.0001). In-hospital complications were more common in patients with combined spine plus pelvic injuries (groups B and D) than in patients with isolated pelvic and acetabular injury (groups A and C). CONCLUSIONS: Delaying definitive surgical treatment of pelvic fractures due to spinal cord injury appears to have a negative impact on the outcome of pelvic fractures, especially on the quality of reduction of acetabular fractures.

Mid-Term Results After 517 Primary Total Hip Arthroplasties With a Shortened and Shoulderless Double-Taper Press-Fit Stem: High Rates of Aseptic Loosening.

BACKGROUND: Shorter double-taper stems with reduced lateral shoulders facilitate implantation via the muscle-sparing direct anterior approach and are becoming increasingly popular. We observed an unusually high number of cases of aseptic loosening with the use of a modified stem. Therefore, the aim of this prospective single-center study was to assess safety and efficacy of this cementless stem. METHODS: A total of 486 consecutive patients receiving 517 primary total hip arthroplasties using the MonoconMIS stem were prospectively followed up for a mean period of 5.29 years (standard deviation [SD], 1.47). Surgical and clinical data, complications, and revision surgeries were analyzed. The Western Ontario and McMaster Universities Arthritis Index (WOMAC) score was recorded before surgery and at one year and five years after surgery. RESULTS: The overall 5-year implant survival rate was 95.2%. The individual component survival rates were 96.1% for the stem, 99.4% for the acetabular cup, and 99.0% for the isolated mobile component exchange. The most common reasons for revision were periprosthetic fracture (1.5%), aseptic stem loosening (1.4%), and infection (1.0%). The WOMAC score improved significantly from 49.57 (SD, 21.42) at baseline to 13.33 (SD, 16.47) at one year and 9.84 (SD, 14.45) at five years after surgery. Aseptic stem loosening occurred only in patients with Dorr type A proximal femur morphology. CONCLUSION: The evaluated femoral stem is associated with revision rates higher than what has been reported for other implants. The WOMAC scores suggest adequate efficacy. Our data do not support the use of the MonoconMIS for primary total hip arthroplasty in patients with Dorr type A proximal femur morphology.

Correlation of Loss of Correction With Postoperative Radiological Factors After Distal Chevron Osteotomy in Dependence of Concomitant Akin Osteotomy.

Loss of correction is frequently observed following hallux valgus correction and is associated with recurrence of a hallux valgus deformity. The purpose of this study was to correlate loss of correction and radiological parameters following distal chevron (Group C) and combined chevron/akin (Group AC) osteotomy. A total of 859 feet were included for analysis and grouped according to treatment with a distal chevron osteotomy alone or a combined chevron/akin osteotomy. Radiographs were evaluated preoperatively, postoperatively, after 6 weeks, 3 months and, if available, at long term follow-up with a mean of 34.2 (range 7.5-155.3) months. With the exception of the proximal to distal phalangeal articular angle (PDPAA), preoperative deformity was comparable between both groups. Significant correction of all examined parameters (p < .001) was seen. Loss of correction at 6 weeks with minor deterioration until follow-up was also detected, with group AC somewhat better than Group C. A strong correlation with loss of correction was found for the postoperative hallux valgus angle (HVA) (p < .002), intermetatarsal angle (IMA) (p < .001), distal metatarsal articular angle (DMAA) (p < .002), positioning of the sesamoids (p < .002) and joint congruity (p < .035) in Group C and for the DMAA (p < .033) and HVA (p < .046) in Group AC. Multiple postoperative radiological parameters correlated with loss of correction following distal chevron osteotomy. In Group AC only postoperative HVA and DMAA determined loss of correction. Correction of the deformity in Group AC showed greater stability.

Survivorship of Ceramic-on-Ceramic Total Hip Arthroplasty With Metal-Backed Acetabular Liners at 10 Years.

BACKGROUND: Ceramic-on-ceramic bearings are becoming increasingly popular in primary total hip arthroplasty (THA). To enhance ceramic-on-ceramic liner exchange in case of revision surgery, metal-backed liner systems have been proposed. Little is known about the clinical performance of these implants. The purpose of this study is to evaluate a metal-backed liner implant system for primary THA. METHODS: A total of 422 patients (with 468 consecutive THAs) were followed over a mean period of 10 years. All arthroplasties were performed with a cementless stem, a press-fit cup, and a metal-backed liner system. Surgical and clinical data, complications, and revisions were analyzed. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) before surgery and at 1 and 10 years after surgery were compared. RESULTS: The overall 10-year implant survival rate was 93.8%. The survival rate was 97.0% for heads and liners, 97.5% for stem, and 99.3% for acetabular cup. The most common reason for revision was ceramic breakage (2.4%) of the third-generation (BIOLOX forte) acetabular liner. Mean WOMAC score improved significantly from 50.1 before surgery to 13.2 at 1 year after surgery. There was no difference in WOMAC scores between surgical approach and type of bearing at 1 and 10 years after surgery. CONCLUSION: THA using cementless stem, press-fit cup, and metal-backed liner system provides satisfactory long-term outcomes, with revision rate comparable to that with other systems available in the market. The metal-backed liner system has low risk of mal-seating. Third-generation ceramic liners should be avoided as they seem to be more prone to breakage.

The negative impact of the COVID-19 lockdown on pain and physical function in patients with end-stage hip or knee osteoarthritis.

PURPOSE: The purpose of this study was to evaluate pain, functional impairment, mental health, and daily activity in patients with end-stage hip and knee osteoarthritis (OA) during the COVID-19 lockdown. METHODS: The study included 63 patients, with hip or knee OA, who had been scheduled for arthroplasty that was postponed because of COVID-19. Patients were evaluated by telephone interviews during the first week after lockdown, in the fourth week, and again at the end of the lockdown. Patients rated their pain level on the basis of a visual analog scale (VAS) and completed WOMAC, SF-12 and Tegner activity scale (TAS) questionnaires. RESULTS: VAS and WOMAC scores increased significantly during lockdown, while physical activity significantly decreased. At the final evaluation, VAS and WOMAC showed a significant negative correlation with TAS. The SF-12 subscale scores showed a significant decrease of the physical component during the lockdown, while the mental component remained largely unchanged. Patients with knee OA showed a faster progress of pain compared to those with hip OA. 50 patients (79%) stated they wished to have arthroplasty as soon as possible. CONCLUSION: The COVID-19 lockdown had a significant impact on pain, joint function, physical function, and physical activity in patients with end-stage hip and knee OA. LEVEL OF EVIDENCE: II (Prospective cohort study).

Differentiation of Predominantly Osteoblastic and Osteolytic Spine Metastases by Using Susceptibility-weighted MRI.

Purpose To evaluate the use of susceptibility-weighted MRI for the differentiation of predominantly osteoblastic and osteolytic spine metastases. Materials and Methods For this prospective study, 53 study participants (mean age, 54.5 years ± 14.3 [range, 22-88 years]; 27 men with a mean age of 55.3 years ± 12.7 [range, 22-72 years] and 26 women with a mean age of 53.8 years ± 15.7 [range, 23-88 years]) with clinically suspected spine metastases underwent imaging with standard MRI sequences, susceptibility-weighted MRI, and CT. Sensitivities and specificities of MRI sequences for the detection of predominantly osteoblastic and osteolytic metastases were determined by using CT as the reference standard. The metastases-to-vertebral body signal intensity ratio (MVR) was calculated to compare modalities. Phantom measurements were obtained to correlate bone densities between MRI sequences and CT. Results A total of 64 metastases (38 predominantly osteoblastic, 26 predominantly osteolytic) were detected. Susceptibility-weighted MRI achieved a sensitivity of 100% (38 of 38) and specificity of 96% (25 of 26) for predominantly osteoblastic metastases and a sensitivity of 96% (25 of 26) and specificity of 100% (38 of 38) for predominantly osteolytic metastases. Standard MRI sequences achieved a sensitivity of 89% (34 of 38) and specificity of 73% (19 of 26) for predominantly osteoblastic metastases and a sensitivity of 73% (19 of 26) and specificity of 92% (35 of 38) for predominantly osteolytic metastases. MVR measurements obtained with susceptibility-weighted MRI demonstrated a strong correlation with those obtained with CT (R2 = 0.75), whereas those obtained with T1-weighted MRI, T2-weighted MRI, and turbo inversion-recovery magnitude MRI showed a weak to moderate correlation (R2 = 0.00, R2 = 0.35, and R2 = 0.39, respectively). Susceptibility-weighted MRI showed a strong correlation with CT with regard to metastases size (R2 = 0.91). In phantom measurements, susceptibility-weighted MRI enabled the reliable differentiation of different degrees of mineralization (R2 = 0.92 compared with CT). Conclusion Susceptibility-weighted MRI enables the reliable differentiation between predominantly osteoblastic and osteolytic spine metastases with a higher accuracy than standard MRI sequences. © RSNA, 2018 Online supplemental material is available for this article. See also the editorial by Schweitzer in this issue.

Evaluation of osseous cervical foraminal stenosis in spinal radiculopathy using susceptibility-weighted magnetic resonance imaging.

OBJECTIVE: The aim of this study was to evaluate the diagnostic performance of susceptibility-weighted magnetic resonance imaging (SW-MRI) for the evaluation of osseous foraminal stenosis (FS) of the cervical spine compared to conventional MRI-sequences, using computed tomography (CT) as a reference standard. MATERIALS AND METHODS: Twenty-one patients with suspected radiculopathy of the cervical spine were prospectively included. CT and MRI data sets were available for all patients. As standard of reference, 280 neuroforamina of the cervical spine, including 58 foraminal stenosis, were identified on sagittal CT images. T1-, T2-, and SW-MRI of the cervical spine were performed. The presence of foraminal stenosis was assessed on sagittal views in all sequences. Sensitivity and specificity were calculated and differences in detection rate and severity scoring of foraminal stenosis between the different sequences were tested. CT was used as reference standard for all analysis. RESULTS: Fifty-six of 58 osseous foraminal stenosis could be correctly identified on SW-MR magnitude images. SW-MRI achieved a sensitivity of 96.6% and specificity of 99.5% for the identification of foraminal stenosis. In comparison, conventional T1-weighted MRI sequences achieved a sensitivity and specificity of 43.1% and 100% respectively. T2-weighted MRI sequences achieved a sensitivity and specificity of 65.5% and 99.1%, respectively. The overall detection rate was significantly (p < 0.05) higher on SW-MRI and there was no significant difference (p > 0.05) in severity scoring compared to CT. T1- and T2-weighted MRI underestimated the degree of foraminal stenosis. Intermodality and interobserver agreements were highest for SW-MRI. CONCLUSIONS: SW-MRI enables the reliable detection of osseous foraminal stenosis of the cervical spine in patients with spinal radiculopathy with a higher sensitivity compared to conventional T1- and T2-MRI sequences, with CT as a reference standard. KEY POINTS: • Susceptibility-weighted magnetic resonance imaging enables the reliable detection of osseous foraminal stenosis of the cervical spine with CT as a reference standard. • This could be relevant for younger patients in order to prevent unnecessary radiation exposure. • This may also facilitate a one-stop-shop approach and speed up diagnostic work-up.

Assessment of the extracellular volume fraction for the grading of clear cell renal cell carcinoma: first results and histopathological findings.

OBJECTIVES: To assess the potential of T1 mapping-based extracellular volume fraction (ECV) for the identification of higher grade clear cell renal cell carcinoma (cRCC), based on histopathology as the reference standard. METHODS: For this single-center, institutional review board-approved prospective study, 27 patients (17 men, median age 62 ± 12.4 years) with pathologic diagnosis of cRCC (nucleolar International Society of Urological Pathology (ISUP) grading) received abdominal MRI scans at 1.5 T using a modified Look-Locker inversion recovery (MOLLI) sequence between January 2017 and June 2018. Quantitative T1 values were measured at different time points (pre- and postcontrast agent administration) and quantification of the ECV was performed on MRI and histological sections (H&E staining). RESULTS: Reduction in T1 value after contrast agent administration and MR-derived ECV were reliable predictors for differentiating higher from lower grade cRCC. Postcontrast T1diff values (T1diff = T1 difference between the native and nephrogenic phase) and MR-derived ECV were significantly higher for higher grade cRCC (ISUP grades 3-4) compared with lower grade cRCC (ISUP grades 1-2) (p < 0.001). A cutoff value of 700 ms could distinguish higher grade from lower grade tumors with 100% (95% CI 0.69-1.00) sensitivity and 82% (95% CI 0.57-0.96) specificity. There was a positive and strong correlation between MR-derived ECV and histological ECV (p < 0.01, r = 0.88). Interobserver agreement for quantitative longitudinal relaxation times in the T1 maps was excellent. CONCLUSIONS: T1 mapping with ECV measurement could represent a novel in vivo biomarker for the classification of cRCC regarding their nucleolar grade, providing incremental diagnostic value as a quantitative MR marker. KEY POINTS: • Reduction in MRI T1 relaxation times after contrast agent administration and MR-derived extracellular volume fraction are useful parameters for grading of clear cell renal cell carcinoma (cRCC). • T1 differences between the native and the nephrogenic phase are higher for higher grade cRCC compared with lower grade cRCC and MRI-derived extracellular volume fraction (ECV) and histological ECV show a strong correlation. • T1 mapping with ECV measurement may be helpful for the noninvasive assessment of cRCC pathology, being a safe and feasible method, and it has potential to optimize individualized treatment options, e.g., in the decision of active surveillance.

Extracardiac findings at cardiac MR imaging: a single-centre retrospective study over 14 years.

OBJECTIVES: To determine the prevalence and significance of extracardiac findings (ECF) in a large set of cardiac magnetic resonance (MR) imaging examinations. METHODS: The institutional review board (IRB) of the Charité approved this retrospective, single-centre study. A total of 4376 cardiac MR imaging reports of 3553 patients (age 37.4 ± 20 years, 60.8 % male) examined from 2000 to 2014 were included. Findings with a recommendation for follow-up were considered "major ECF". To analyse the association of indication, age and gender with ECF, Poisson regression and computed incidence rate ratios (IRR) were evaluated. RESULTS: The overall prevalence of ECF was 34% (95% confidence interval [CI] 32.5-35.6%). Major ECF were present in 3.4% (95% CI 2.9-4.1%) while findings that changed patient management were found in 0.9% (95% CI 0.7-1.3%). In the cases of congenital heart disease, ECF prevalence was higher compared to myocarditis (IRR, 6.0; 95% CI 5.1-7.1%; p < 0.001), while the prevalence of major ECF was lower (IRR, 0.2; 95% CI 0.02-0.51%; p < 0.05). Older patient age was associated with more nonvascular ECF (p < 0.001). Female patients had the same probability of having an ECF as male patients (IRR, 1.04; 95% CI 0.95-1.1%; p = 0.43). CONCLUSION: ECF in cardiac MR imaging are present in about every third patient while relevant ECF that change patient management can be found in about one out of 100 patients. Our data suggest that it is important to involve well-trained radiologists in reading cardiac MR images, which often reveal ECF if congenital heart disease is the clinical indication. KEY POINTS: • Extracardiac findings are present in about every third patient. • Relevant ECF changing patient management are found in one out of 100 findings. • Chance of ECF is high in patients with CHD and vascular indications.

Evaluation of vertebral body fractures using susceptibility-weighted magnetic resonance imaging.

PURPOSE: To test the diagnostic performance of susceptibility-weighted MRI (sMRI) for the evaluation of vertebral body fractures versus standard MRI-sequences, using CT as reference standard. METHODS: In this prospective study 88 vertebral fractures (45 healed, 43 non-healed) were detected in 39 patients who underwent T1/T2/TIRM MRI-sequences and sMRI. All fractures were evaluated with CT as reference standard. In all modalities/sequences, displacement and height of the posterior vertebral body cortex and visibility of fracture lines and cortical breaks were assessed. Sensitivity, specificity and inter-reader agreement between MRI and CT were calculated. RESULTS: sMRI demonstrated highest diagnostic accuracy for detection of posterior vertebral body cortex involvement (sensitivity: 98 %/specificity: 100 %), fracture lines (86 %/99 %) and cortical breaks (93 %/100 %) versus T1/T2/TIRM sequences. Regarding evaluation of posterior vertebral body cortex displacement and height, sMRI demonstrated the closest intermodality agreement (R2=0.96; 95 % CI -0.92-0.89/R2=0.97; 95 % CI -1.67-1.23) with CT and the closest interobserver agreement (R2=0.97; 95 % CI -0.71-1.01). CONCLUSION: sMRI allows reliable evaluation of vertebral body fractures with regard to posterior vertebral body cortex displacement and height, cortical breaks and fracture lines with higher accuracy versus standard MRI, especially in patients with non-healed vertebral body fractures. KEY POINTS: • sMRI allows a reliable evaluation of vertebral body fractures. • sMRI has higher accuracy than standard-MRI for evaluation of vertebral body fractures. • sMRI is especially useful in patients with non-healed vertebral body fractures.

Image quality of low-radiation dose left atrial CT using filtered back projection and an iterative reconstruction algorithm: intra-individual comparison in unselected patients undergoing pulmonary vein isolation.

Background Computed tomography (CT) of the left atrium (LA) is performed prior to pulmonary vein isolation (PVI) to improve success of circumferential ablation for atrial fibrillation. The ablation procedure itself exposes patients to substantial radiation doses, therefore radiation dose reduction in pre-ablational imaging is of concern. Purpose To assess and compare diagnostic performance of low-radiation dose preprocedural CT in patients scheduled for PVI using two types of reconstruction algorithms. Material and Methods Forty-six patients (61 ± 10 years) scheduled for PVI were enrolled in this study irrespective of body-mass-index or cardiac rhythm at examination. An electrocardiographically triggered dual-source CT scan was performed. Filtered back projection (FBP) and iterative reconstruction (IR) algorithms were applied. Images were integrated into an electroanatomic mapping (EAM) system. Subjective image quality was scored independently by two readers on a five-point scale for both reconstruction algorithms (1 = excellent to 5 = non-diagnostic). Signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and effective radiation dose were calculated. Results Data acquisition and EAM integration were successful in all patients. Median image quality score was 1 for both FBP (quartiles = 1, 1.62; range = 1-3) and IR (quartiles = 1, 1.5; range = 1-3). Mean SNR was 7.61 ± 2.14 for FBP and 9.02 ± 2.69 for IR. Mean CNR was 5.92 ± 1.80 for FBP and 6.95 ± 2.29 for IR. Mean effective radiation dose was 0.3 ± 0.1 mSv. Conclusion At a radiation dose of 0.3 ± 0.1 mSv, high-pitch dual-source CT yields LA images of consistently high quality using both FBP and IR. IR raises SNR and CNR without significantly improving subjective image quality.

Assessment of intracranial meningioma-associated calcifications using susceptibility-weighted MRI.

PURPOSE: To determine the diagnostic accuracy of susceptibility-weighted MRI (SW-MRI) for the detection of intracranial meningioma-associated calcifications compared with standard MR sequences, using computed tomography (CT) as a reference standard. MATERIALS AND METHODS: 354 patients, who had received both a CT and a 1.5 Tesla clinical brain MRI with SW-MRI sequences between January 2014 and July 2016, were retrospectively evaluated and 316 patients were included. Calcification diameter was used to assess correlation between imaging modalities. Sensitivity and specificity as well as intra- and interobserver agreement were calculated for SW-MRI and standard MRI sequences when compared with reference standard CT. RESULTS: Fifty patients had positive findings for intracranial meningioma-associated calcifications on CT scans. SW-MRI reached a sensitivity of 94% (95% confidence interval [CI]: 83-99%) and a specificity of 95% (95% CI: 92-98%) for the detection of meningioma-associated calcifications, while standard MRI yielded a sensitivity of 64% (95% CI: 49-77%) and a specificity of 94% (95% CI: 90-96%). Diameter measurements between SW-MRI and CT showed a close correlation (R2 = 0.99; P < 0.001) with a slight overestimation of size, which, however, did not reach significance level (SW-MRI: 8.2 mm ± 7.1; CT: 6.8 mm ± 6.4; P = 0.29). Compared with standard MRI, SW-MRI showed a better interobserver agreement for size measurements of calcifications. CONCLUSION: SW-MRI enables a reliable detection of intracranial meningioma-associated calcifications by using CT as a reference and offers a higher diagnostic accuracy than standard MRI. LEVEL OF EVIDENCE: 3 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2017;46:1177-1186.

Detection of vessel wall calcifications in vertebral arteries using susceptibility weighted imaging.

PURPOSE: Calcification of the brain supplying arteries has been linked to an increased risk for cerebrovascular disease. The purpose of this study was to test the potential of susceptibility weighted MR imaging (SWMR) for the detection of vertebral artery calcifications, based on CT as a reference standard. METHODS: Four hundred seventy-four patients, who had received head CT and 1.5 T MR scans with SWMR, including the distal vertebral artery, between January 2014 and December 2016, were retrospectively evaluated and 389 patients were included. Sensitivity and specificity for the detection of focal calcifications and intra- and interobserver agreement were calculated for SWMR and standard MRI, using CT as a standard of reference. The diameter of vertebral artery calcifications was used to assess correlations between imaging modalities. Furthermore, the degree of vessel stenosis was determined in 30 patients, who had received an additional angiography. RESULTS: On CT scans, 40 patients showed a total of 52 vertebral artery calcifications. While SWMR reached a sensitivity of 94% (95% CI 84-99%) and a specificity of 97% (95% CI 94-98%), standard MRI yielded a sensitivity of 33% (95% CI 20-46%), and a specificity of 93% (95% CI 90-96%). Linear regression analysis of size measurements confirmed a close correlation between SWMR and CT measurements (R 2 = 0.74, p < 0.001). Compared to standard MRI (ICC = 0.52; CI 0.45-0.59), SWMR showed a higher interobserver agreement for calcification measurements (ICC = 0.84; CI 0.81-0.87). CONCLUSIONS: For detection of distal vertebral artery calcifications, SWMR demonstrates a performance comparable to CT and considerably higher than conventional MRI.