Eleni E. Drakonaki

Ultrasound elastography for musculoskeletal applications

Ultrasound elastography (EUS) is a method to assess the mechanical properties of tissue, by applying stress and detecting tissue displacement using ultrasound. There are several EUS techniques used in clinical practice; strain (compression) EUS is the most common technique that allows real-time visualisation of the elastographic map on the screen. There is increasing evidence that EUS can be used to measure the mechanical properties of musculoskeletal tissue in clinical practice, with the future potential for early diagnosis to both guide and monitor therapy. This review describes the various EUS techniques available for clinical use, presents the published evidence on musculoskeletal applications of EUS and discusses the technical issues, limitations and future perspectives of this method in the assessment of the musculoskeletal system.

Magnetic resonance imaging, ultrasound and real-time ultrasound elastography of the thigh muscles in congenital muscle dystrophy

Congenital muscle dystrophy includes a range of genetic disorders characterized by muscle weakness and contractures. We report the magnetic resonance (MR), ultrasound (US) and real-time sonoelastography (RTE) imaging findings of the thigh muscles of a 15-year-old boy with Bethlem myopathy diagnosed with clinical, electromyographic and histopathological criteria. Ultrasound and MR showed hyperechoic appearance and high signal intensity on T1- and T2-weighted sequences respectively at the periphery of the vastus lateralis and the long head of the biceps femoris muscles, and at a central area within the rectus femoris muscles. RTE was employed to examine the elastic properties of the muscle. The elastograms were presented as colour-coded maps superimposed on the B-mode images and revealed that the elastographic pattern correlated with the MR and US pattern of involvement. The abnormal muscle areas were stiffer (blue) than the normal-appearing areas (green), a finding that probably correlates with the presence of dystrophic collagen at the affected areas. This report suggests that RTE could be used as an additional imaging tool to evaluate the pattern of muscle changes in congenital myopathy. Further studies are needed to investigate the specificity and clinical value of RTE in the diagnosis and monitoring of neuromuscular disease.

The role of MR imaging in avascular necrosis of the femoral head.

Due to the pattern of its blood supply, the femoral head is particularly vulnerable to avascular necrosis (AVN). Nontraumatic AVN is a devastating disorder affecting young patients, and despite treatment it normally follows a progressive course toward a destructive osteoarthropathy. Magnetic resonance (MR) imaging is currently used in major classification systems solely for early detection of femoral head AVN when plain radiographs are normal. More recent data have shown that MR imaging may improve staging, investigate radiologically occult collapse, depict other causes of disability and pain, assess prognosis, and evaluate treatment. This article reviews the established and evolving role of MR imaging in patients at risk or with known femoral head AVN.

Adrenal glands in beta-thalassemia major: magnetic resonance (MR) imaging features and correlation with iron stores.

This study aimed at describing the magnetic resonance (MR) imaging features of the adrenal glands in beta-thalassemic patients and at investigating the relation between adrenal and hepatic siderosis. Adrenal signal intensity (SI) was retrospectively assessed on abdominal MR studies of 35 patients with beta-thalassemia major undergoing quantification of hepatic siderosis and 12 healthy controls, using T1- (120/4/90), intermediate - (120/4/20), and T2*- (120/15/20) weighted GRE sequences. Adrenal SI was graded as grade 0 (normal SI on all sequences), grade 1 (hypointensity on T2* alone), or grade 2 (hypointensity on at least T2*). Adrenal size was measured in the thalassemic patients and compared with normative data. Liver-to-muscle (L/M) SI ratios, expressing hepatic siderosis, were estimated on each sequence. Serum ferritin levels were recorded. Adrenal hypointensity (grades 1 and 2) was noted in 24/35 (68.6%) patients. L/M ratios correlated significantly with adrenal SI in all sequences. Patients with grade 1 and grade 2 adrenal SI had significantly decreased L/M ratios compared with grade 0. Serum ferritin correlated significantly with L/M values but not with adrenal SI. Adrenal size was within normal limits. Diffuse hypointensity in normal-sized adrenals is a common MR finding in beta-thalassemic patients and correlates with the degree of hepatic siderosis.

Bone marrow changes in beta-thalassemia major: quantitative MR imaging findings and correlation with iron stores

The purpose of this study is to describe the MR imaging features of bone marrow in beta-thalassemia major and investigate their relation to ferritin, liver and spleen siderosis. Spinal bone marrow was prospectively assessed on abdominal MR studies of 40 transfused beta-thalassemic patients and 15 controls using T1-w, Pd, T2*-w Gradient Echo (GRE) and T1-w turbo Spin Echo (TSE) sequences. Signal intensity (SI) ratios of liver, spleen and bone marrow to paraspinous muscles (L/M, S/M, B/M respectively) and the respective T2 relaxation rates (1/T2) were calculated. Serum ferritin levels were recorded. Bone marrow hypointensity in at least T2*-w GRE sequence was noted in 29/40 (72.5%) patients. Eleven/40 patients exhibited normal B/M on all MR sequences. Five/40 patients had normal B/M and low L/M. B/M correlated with L/M in T1-w TSE sequence only (r = 0.471, p = 0.05). B/M correlated with S/M and mean ferritin values in all sequences (r > 0.489, p < 0.01 and r  >  − 0.496, p < 0.03 respectively). Marrow 1/T2 did not correlate with ferritin values or liver and spleen 1/T2. B/M in transfused beta-thalassemic patients is related to splenic siderosis and ferritin levels. Although marrow is usually hypointense, it may occasionally display normal SI coexisting with liver hypointensity, a pattern typical of primary hemochromatosis.

Deferoxamine Versus Combined Therapy for Chelating Liver, Spleen and Bone Marrow Iron in β-Thalassemic Patients: A Quantitative Magnetic Resonance Imaging Study

We used magnetic resonance imaging (MRI) to compare the effect of iron chelation on liver, spleen and bone marrow. We examined 21 β-thalassemic patients undergoing deferoxamine (DFO) (9/21) or combined therapy [DFO and deferiprone (L1), 12/21] with two abdominal MRI studies using T1-w/Pd-w/T2*-wGRE and T1-wTSE sequences. Changes in serum ferritin (DF%), and liver, spleen and marrow to paraspinous muscles signal intensity ratios (SI) in T1-wTSE sequence were calculated as D%=[(2ndvalue-1st value)/1st value] ×100%. Negative DF% and positive D(SI)% indicated reduction of iron. Although 17/21 (80.9%) patients demonstrated reduction in ferritin, only 8/21 (38%), 7/21 (33.3%) and 7/21 (33.3%) patients had decreased liver, spleen and marrow iron. Patients undergoing combined therapy showed significantly greater reduction (Students t-test, p < 0.05) or less increase (t-test, p <0.05) in iron stores. Combined therapy is more effective than DFO for removing and preventing liver, spleen and bone marrow iron accumulation in β-thalassemic patients. Magnetic resonance imaging is valuable for organ-specific monitoring of chelation therapy.

High-resolution ultrasound in the diagnosis of upper limb disorders: a tertiary referral centre experience.

The purpose of this study is to determine the reliability of high-resolution ultrasound (HRUS) in the diagnosis of upper limb disorders compared with the initial clinical opinion. We prospectively studied 178 patients referred for HRUS examination (47.2% hand, 34.8% wrist, and 18% elbow examinations) by recording the clinical opinion, the specific ultrasound diagnosis, and the final diagnosis, as established by surgery (79.9%) or follow-up (20.1%). HRUS examination was highly reliable in diagnosing cystic lesions, synovial disease, ligament injury and foreign bodies (100%), and slightly less reliable for solid lesions (82.1%) and nerve, bone, and tendon disorders (97%, 91.7%, 86.5%, respectively). HRUS examination resulted in significantly more correct diagnoses (92.1%) than the clinical opinion (70.8%) (McNemar test, P = 0.001). The agreement between the HRUS diagnosis and the clinical opinion was slight (Kappa test, k = 0.16). HRUS examination is more reliable than clinical examination in diagnosing upper limb disorders.

Ultrasound-guided intervention in the ankle and foot.

In this comprehensive review, we discuss the main interventions performed in the foot and ankle for Achilles tendinopathy, Mortons neuromas and Plantar fasciitis as well as techniques for intra-articular and peritendinous injections. We present the different imaging techniques and injectable agents that can be used in clinical practice, trying to help the reader decide the most appropriate way of managing the patient with a problem in the ankle and foot.

EVALUATION OF IRIDOCILIARY AND LENTICULAR ELASTICITY USING SHEAR-WAVE ELASTOGRAPHY IN RABBIT EYES

INTRODUCTION A previous study has employed shear-wave ultrasound elastographic imaging to assess corneal rigidity in an ex-vivo porcine eye model. This study employs the same modality in vivo in a rabbit eye model in order to assess lens, ciliary body and total ocular rigidity changes following the instillation of atropine and pilocarpine. METHODS Ten non-pigmented female rabbits were examined. Measurements of the lens, ciliary body and total ocular rigidity as well as lens thickness and anterior chamber depth were taken with the Aixplorer system (SuperSonic Imagine, Aix-en-Provence, France) with the SuperLinear™ SL 15-4 transducer in both eyes at baseline as well as after pilocarpine and atropine instillation. The IOP was also measured with the TonoPen tonometer. RESULTS Changes in rigidity in the examined areas following atropine instillation were statistically not significant. Ciliary body rigidity was significantly increased whereas lens and total ocular rigidity were significantly reduced following pilocarpine instillation. The decrease in lens rigidity following pilocarpine was significantly associated with the respective increase in ciliary body rigidity. CONCLUSIONS Shear-wave ultrasound elastography can detect in vivo rigidity changes in the anterior segment of the rabbit eye model and may potentially be applied in human eyes, providing useful clinical information on conditions in which rigidity changes play an important role, such as glaucoma, pseudoexfoliation syndrome or presbyopia.

Hypertrophic osteoarthropathy in a child due to thoracic Hodgkin's disease

Keywords Hodgkins disease.Osteoartropathy.Radiographs.CTThere is periosteal reaction along the shaft of the longbones of the hand and foot, leading to the diagnosis ofhypertrophic osteoarthropathy (HPOA), associated withintrathoracic Hodgkin’s disease.DiscussionHypertrophic osteoarthropathy in children is rare and istypically considered to be a sign of pulmonary disease [1–3]. However, it may be related to a variety of inflammatoryor neoplastic disorders, including congenital heart diseases,pulmonary or cystic fibrosis, infectious airway disease,chronic liver and inflammatory bowel disease as well asvarious intrathoracic and gastrointestinal tumours [1–3].While up to 90% of HPOA cases are associated withprimary or metastatic pulmonary neoplasms in adults,intrathoracic malignant disease accounts for only 12% ofHPOA cases in children [1–3]. The presence of HPOA hasbeen regarded as a poor prognostic sign, since most of thepatients with malignancy and HPOA have showed exten-sive metastases [2]. Therefore, although HPOA is rare inchildhood cancers, its occurrence should alert physiciansfor the recurrence of disease or intrathoracic involvementduring follow-up [2–4].HPOA has a characteristic radiological appearance [1–4]. Initially, there is periosteal new bone formation forminga thin radiopaque line around the cortex and separated fromit by a radiolucent band. In our patient, this pattern isevident at both the X-rays, and the CT. Subsequently, thetwo layers gradually fuse and lead to poorly demarcated orlamellar periosteal reaction. This appearance may be easilydifferentiated from bone involvement from the Hodgkin’sdisease itself, as periosteal infiltration by lymphoma usuallyaffects the anterior surfaces of the vertebral bodies ratherthan the long bones and is always associated with corticalbone destruction [1–4].In pediatric Hodgkin’s lymphoma,