Skeletal Radiology

Test Yourself: Question: "Painless right leg swelling"

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Skeletal Radiology: The Year in Review 2018

Selective rickets from localized advanced maturation—a case report Abstract An unusual cause of rickets is illustrated by a patient with infantile multisystem inflammatory disease who, by age 2 years and 4 months, developed striking radiographic and clinical rickets restricted to those joints involved by the inflammatory process. The locally increased vascularity from his inflammation led to increased maturation at those sites so rapid as to override the usual enchondral calcification, thus causing a rickets pattern. Other sites, such as the proximal humeri, lacking any inflammation, showed no increased maturation rate and did not manifest local rickets. Rapid local bone maturation may cause localized rickets.

Osteoma-like melorheostosis: a rare type of skeletal dysplasia depicted on FDG PET/CT Abstract Melorheostosis, also known as Leri's disease, is a rare benign form of mesodermal mixed sclerosing bone dysplasia. We report the unusual case of a 14-year-old boy with melorheostosis in the lower extremity that went undiagnosed due to concurrent Ewing sarcoma in the opposite limb, confounding the findings for metastatic disease. The diagnosis was made on FDG PET/CT when the patient presented for post Ewing sarcoma treatment follow-up. The different types of melorheostosis as well as the challenge of diagnosing this rare entity are discussed in this report.

Test yourself: question: "painless right leg swelling"

Primary infectious costochondritis due to Prevotella nigrescens in an immunocompetent patient: clinical and imaging findings Abstract Infection of costal cartilage is a rare observation. We report the case of a 43-year-old male patient without relevant history who presented with a progressive painful swelling of the left chest wall since 4 months. Computed tomography (CT) and magnetic resonance imaging (MRI) demonstrated an abscess within the left ninth costal cartilage with surrounding reactive changes. A CT-guided biopsy was performed and the culture of the sample revealed the presence of Prevotella nigrescens. Musculoskeletal infections by Prevotella are rarely described in the literature, Prevotella oralis and Prevotella bivia being the most frequently observed pathogens. These infections usually originate from a hematogenous spread after thoracic surgery or dental procedure. In our patient, conservative treatment was chosen. A clinical improvement was noted after 1-month antibiotherapy, confirmed by short-term and 6-month imaging follow-up showing the complete disappearance of all previously observed abnormalities.

Shear-wave elastography of the ulnar collateral ligament of the elbow in healthy volunteers: a pilot study Abstract Objective To estimate the intra-observer repeatability of shear wave elastography in the UCL of the elbow, and to compare shear wave velocities between dominant and non-dominant arms. Materials and methods Twenty elbows in ten healthy volunteers were evaluated [five males, five females; mean age, 31.8 ± 10.3 years]. Shear wave velocity was measured on three separate days during the span of 1 week utilizing a linear 18-MHz transducer. Elastograms were obtained until ten ROIs were drawn, not drawing more than two ROIs on any elastogram. Elastograms were considered diagnostic if any portion of the UCL was colored in and free of boundary artifacts. Median velocity and interquartile range were recorded. A result was considered reliable if the IQR/median ratio of the ten measurements was < 0.3. Results IQR/median was < 0.3 in 88% of sessions, although in 28% of sessions fewer than 60% of elastograms were diagnostic. The ICC was 0.05 (95% CI; − 0.18–0.36; poor). Repeatability coefficient (95% limits of agreement) was 1.95 m/s (95% CI; 1.61–2.37 m/s). Mean velocity in dominant arms was 5.14 ± 0.53 m/s and 5.24 ± 0.39 m/s in non-dominant (p = 0.558). Conclusions Mean shear wave velocity was similar between dominant and non-dominant arms. Although repeatability was poor as assessed by ICC, the repeatability coefficient may be a more useful indicator of clinical utility once shear wave velocities in diseased ligaments are explored. Future studies should therefore evaluate velocities in diseased ligaments and develop techniques to improve elastogram quality.

Optimizing radiation dose parameters in MDCT arthrography of the shoulder: illustration of basic concepts in a cadaveric study Abstract Objective To determine in a cadaveric study the lowest achievable radiation dose and optimal tube potential generating diagnostic image quality in multidetector computed tomography (MDCT) arthrography of the shoulder. Materials and methods Six shoulders from three human cadavers were scanned using a 256-MDCT system after intra-articular injection of diluted iodinated contrast material. Using six decreasing radiation dose levels (CTDIvol: 20, 15, 10, 8, 6, and 4 mGy) and for each dose level, four decreasing tube potentials (140, 120, 100, and 80 kVp), image noise and contrast-to-noise ratio (CNR) were measured. Two independent and blinded observers assessed the overall diagnostic image quality, subjective amount of noise, and severity of artifacts according to a four-point scale. Influence of those MDCT data acquisition parameters on objective and subjective image quality was analyzed using the Kruskal–Wallis and Wilcoxon signed-rank tests, and pairwise comparisons were performed. Results Multidetector CT protocols with radiation doses of 15 mGy or higher, combined with tube potentials of 100 kVp or higher, were equivalent in CNR to the reference 20 mGy–140 kVp protocol (all p ≥ 0.054). Above a CTDIvol of 10 mGy and a tube potential of 120 kVp, all protocols generated diagnostic image quality and subjective noise equivalent to the 20 mGy–140 kVp protocol (all p ≥ 0.22). Conclusions Diagnostic image quality in MDCT arthrography of the shoulder can be obtained with a radiation dose of 10 mGy at an optimal tube potential of 120 kVp, corresponding to a reduction of up to 50% compared with standard-dose protocols, and as high as 500% compared with reported protocols in the literature.

Volume of hip synovitis detected on contrast-enhanced magnetic resonance imaging is associated with disease severity after collapse in osteonecrosis of the femoral head Abstract Objective To evaluate the relationship between the volume of hip synovitis detected on contrast-enhanced magnetic resonance imaging (MRI) and the disease stage of osteonecrosis of the femoral head (ONFH). Materials and methods Sixty-three consecutive hips in 40 ONFH patients were reviewed using contrast-enhanced MRI. Ten unaffected hips in 10 patients with unilateral ONFH were used as controls. Based on the Japanese Investigation Committee system, these hips were classified according to stage and type. The volume and location of hip synovitis were semi-quantitatively measured on contrast-enhanced MRI. Clinicoradiological factors were statistically analyzed to determine the relationship with the volume of hip synovitis. Results The mean synovial volume was significantly larger in ONFH hips (8,020 ± 6,900 mm3) than in controls (910 ± 1,320 mm3; p = 0.001). The area of synovitis in the anterior portion of the hip joint was double (mean: 2.17 ± 1.77) that in the posterior portion. The volume of synovitis was small in pre-collapse-stage hips (stage 1: 680 ± 690 mm3, stage 2: 1,460 ± 1,200 mm3), but significantly larger in post-collapse-stage hips (stage 3A: 7,820 ± 4,490 mm3, stage 3B: 13,850 ± 7,110 mm3; p < 0.001). Multiple regression analysis showed that disease stage was the only factor related to hip synovitis. Conclusions Our study suggests that hip synovitis in ONFH might occur after femoral head collapse and worsen with collapse progression, mainly in the anterior portion.

Alexandros Sfakianakis
Anapafseos 5 . Agios Nikolaos
Crete.Greece.72100
2841026182

6948891480

alsfakia@gmail.com