Imaging of spondylodiscitis.

BACKGROUND: Spinal infections (pyogenic or non-pyogenic) are increasing in incidence and are a common cause of morbidity in high-risk patients (elderly, immunocompromised patients, diabetic patients, drug addicts, and patients with sickle-cell disease). AIM: To provide an overview of the radiological features of spinal infections, focusing on magnetic resonance (MR) imaging, and to illustrate the differential diagnosis. MATERIALS AND METHODS: We reviewed the spine imaging of 118 patients with spinal infections from our files. All patients underwent radiography and MR imaging examinations. computed tomography (CT) was performed in 96 patients. RESULTS: MR imaging has greatly contributed to prompt diagnosis, thus allowing implementation of timely appropriate treatment. CONCLUSIONS: Prompt diagnosis and treatment are essential to prevent serious bone and joint destruction, and severe neurologic sequelae.

Recurrent vertebral hydatid disease: spectrum of MR imaging features.

INTRODUCTION: This study aimed to describe a spectrum of magnetic resonance (MR) imaging findings in a case series of four patients with recurrent vertebral hydatid disease (HD). METHODS: Four patients with recurrent spinal HD, who were studied with MR imaging at 1.5T or 0.5T MR units, were encountered during a ten-year period. All patients had a history of repeated spinal surgery for hydatid resection. RESULTS: HD involving the lumbar spine was found in two patients, the thoracolumbar spine in one patient and the lumbosacral in one patient. Skip lesions were seen in one patient. All patients had extensive involvement of the extradural space, soft tissues of the back and posterior vertebral elements. HD involving the vertebral body, intervertebral disk and iliopsoas muscles were noted in three, two and three patients, respectively. Bone and extradural hydatids were typically small, and appeared hypointense on T1-weighted images, with a mildly enhancing rim on post-contrast T1-weighted images. Sacral hydatid was an expansile multicystic process. Muscle hydatids were large, surrounded by a gadolinium-enhancing rim and assumed a variety of patterns - either multilocular or a nonspecific inhomogenous cystic or dumbbell configuration. CONCLUSION: MR imaging is a valuable diagnostic tool for follow-up of patients with vertebral HD. Recurrent HD is characterised by extensive involvement of soft tissues of the back and extradural space. Extension into the intervertebral disk and iliopsoas muscles and skip lesions in the extradural space are not uncommon.

The roots of radiology in Greece.

This article presents as reliably as possible the roots of the Radiology specialty in Greece, from the time of the discovery of X-rays by WC Roentgen. It mentions the most important dates relevant to the foundation of the specialty of Radiology in Greece.

Augmentation of cortical bone mineral density in women with polycystic ovary syndrome: a peripheral quantitative computed tomography (pQCT) study.

BACKGROUND: Women with polycystic ovary syndrome (PCOS) may have increased cortical bone mineral density (BMD) and probably higher bone material quality as well as better resistance in the compression strength of the tibia, measured by peripheral quantitative computed tomography (pQCT), in comparison with that of age-matched healthy subjects. METHODS: Thirty women with PCOS, (15 lean and 15 obese) and 15 age-matched healthy controls were enrolled in this study. The clinical, biochemical and ultrasound characteristics of the two groups were evaluated. Using pQCT, the following parameters were measured: volumetric cortical density (CBD) and volumetric trabecular density (TBD) BMD, total bone cross-sectional area (ToA), cortical area (CoA), cortical thickness (CRT-THK-C) and finally the strength-strain index (SSI). RESULTS: The geometrical parameters (CoA, ToA, CRT-THK-C), the SSI as well as the TBD were increased in the PCOS women; however, these differences did not achieve statistical significance between lean PCOS women, obese PCOS women, and controls. Conversely, CBD was significantly higher in PCOS women compared with controls (P < 0.000) and furthermore in lean PCOS women compared with obese ones (P < 0.01040). CONCLUSIONS: The PCOS women of our study seem to have a higher quality of bone material in the distal tibia and probably a better resistance of bone in the compression strength without alterations in bone mass and geometry (especially the lean PCOS women), indicating that our oligomenorrheic and hyperandrogonemic PCOS women may be protected from the development of osteoporosis and fracture risk later in life.

A pilot finite element study of an osteoporotic L1-vertebra compared to one with normal T-score.

In this paper, two patient-specific finite element (FE) models of both an L1 vertebra with a normal T-score and a mildly wedging, osteoporotic one were created and analysed under usual action. Utilising commercial software packages for image processing and FE analysis (FEA) along with in house computer codes for a posteriori assignment of material properties, in vivo high-resolution spiral computed tomography of the entire vertebrae and FEA were combined. Using the vertebra with a normal T-score as baseline it was found that the maximum value of the von Mises stress in the osteoporotic vertebra was 60% higher but still far below bone strength, while the maximum value of von Mises strain in the same vertebra was 148% higher than that of the vertebra with normal T-score. In the vertebra with normal T-score, 17% of its volume exhibited values of von Mises strain higher than the threshold of 4500 µstrains, referenced by Homminga et al. as a threshold of fracture risk, while in the osteoporotic one this percentage was raised up to 37%. The results suggested that the osteoporotic vertebra is susceptible to fracture due to raised strains and not stresses.

Gallstones and biliary sludge in Greek patients with complete high spinal cord injury: an ultrasonographical evaluation.

INTRODUCTION: We used ultrasonography to detect the presence of biliary sludge or gallstones in Greek patients with complete high spinal cord injury (SCI) above the seventh thoracic segment (T7), within the first six months from injury onset, in order to evaluate the effects of neurological instability and dysfunction of the sympathetic nervous system (SNS) on the gallbladder function in the early post-SCI phase. METHODS: We evaluated 78 asymptomatic patients (57 males, 21 females; mean age 34.8 (range 19-56) years) with complete high SCI located above the T7 segment, and 78 healthy subjects (59 males, 19 females; mean age 35.2 (range 21-59) years) matched for age, gender and race, for a total period of 39 months. All the participants underwent ultrasonographical examination of the gallbladder and common bile duct within the first six months from the injury, in order to investigate the development of biliary sludge and gallstones. RESULTS: The incidence of biliary sludge was significantly higher in patients with SCI compared with the control group. The incidence of biliary sludge and gallstones was also significantly higher in patients with SCI patients in comparison with the healthy subjects. In male SCI patients, the incidence of biliary sludge was significantly increased in comparison with healthy subjects. No significant difference was revealed between the two groups in detection of gallstones. CONCLUSION: Our study indicates that the detection of gallbladder sludge and gallstones are significantly higher in Greek patients with complete high SCI above the T7 segment, as compared with healthy control subjects within the first six months of the injury onset. The complete disruption of the SNS and the neurological instability in the early post-SCI phase is probably responsible for the biliary sludge and gallstone formation. Our results suggest that ultrasonography should be performed in these patients at the first 3-6 months from the injury for the early diagnosis of the lithogenic bile.

A finite element analysis of a T12 vertebra in two consecutive examinations to evaluate the progress of osteoporosis.

Osteoporosis is a metabolic disease that causes bones to become fragile and be more likely to break. As basic clinical examinations to detect osteoporosis, dual energy X-ray absorptiometry (DXA) and quantitative computer tomography (QCT) are used. In the framework of a typical clinical examination, QCT scans were obtained from the T12 vertebra of an elderly woman and osteoporosis was diagnosed. One year later, new QCT scans were obtained in order to evaluate her clinical condition. Using both sets as primary information, two patient-specific finite element (FE) models were created and analyzed under compressive load. Vertebral bone was treated as orthotropic material and its elastic modulus was set as an indirect function of Hounsfield Units (HU). Commercial software for medical image processing and FE analysis, along with in house codes, were used for the mechanical analysis of the FE models. Alterations in the geometry/shape of the vertebra as well as in the distributions of several mechanical quantities were detected between the two FE models. As far as the volume of the vertebra is concerned, it augmented by a percentage of 9.7% while the volume of the vertebral body alone increased by 5.6%. In all the maximum values of the mechanical quantities a measurable reduction was observed (axial compressive displacement: 37.9%, von Mises stress: 23.8%, von Mises strains: 15.1%) and all the investigated distributions in the second FE model became smoother. Finally, the percentage of volume with von Mises strains greater than 4500 microstrain dropped from 8.9%, in the first examination, to 4.9% in the second one. Clinically, the prescribed medication seems to have reinforced the structural stability of the vertebra as a whole and through external remodeling the shape of the vertebra changed in a way that the majority of its volume was relieved from stresses and strains of high magnitude.

Gray-scale and color Doppler ultrasonographic evaluation of reactivated post-traumatic/postoperative chronic osteomyelitis.

OBJECTIVE: We aimed to carry out a systematic assessment of gray-scale and color Doppler ultrasonography (CDUS) findings of reactivated post-traumatic/postoperative chronic osteomyelitis (COM) in adults. MATERIALS AND METHODS: Gray-scale and color Doppler ultrasonography were performed on 40 consecutive patients with a history of long-standing post-traumatic/post-operative chronic osteomyelitis and clinical suggestion of reactivation, in a 32-month-period. All patients had metallic implants: 16 internal fixations, nine external fixations, 11 hip arthroplasties and four knee arthroplasties. The final diagnosis of reactivated COM was based upon biopsy findings, with microbiological and histological examination (n = 27), or a combination of laboratory, clinical and magnetic resonance (MR) findings (n = 13). The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of sonographic signs, including fistulous tracts, periosteal thickening, cortical discontinuity, soft tissue abscess and cellulitis, juxtacortical fluid, distension of the pseudocapsule in arthroplasties, and periosteal vascularity, were estimated. RESULTS: Statistically significant differences between patients with and without reactivated COM were found for fistulous tracts (P < 0.0001), juxtacortical fluid collections (P < 0.001) periosteal thickening (P < 0.01), distension of pseudocapsule (P < 0.05), and periosteal vascularity (P < 0.0001). Low-resistance arterial flow of periosteal vessels presented the highest sensitivity (92%), specificity, and PPV (100%), yielding only two false negative results in two obese patients. Among gray-scale findings, the presence of a fistulous tract yielded the highest specificity and PPV (100%), whereas periosteal thickening was the most sensitive (92%), though not specific, finding (specificity 50%). CONCLUSION: A constellation of gray-scale and CDUS findings can be highly indicative of reactivated bone infection in patients with long-standing chronic post-traumatic/post-operative osteomyelitis.

Hemodynamic alterations and wall properties in large arteries of young, normotensive, and non-obese women with polycystic ovary syndrome.

Young, normotensive, and non-obese women with polycystic ovary syndrome (PCOS) may present abnormal hemodynamic alterations (HA). The purpose of this study was to investigate heart rate (HR), intima-media thickness (IMT), and diameter (DCCA) in the common carotid arteries (CCA), flow velocities, and resistance index in both extracranial carotid and vertebral arteries (VA), in the abdominal aorta (AO) and in the renal arteries (RA) in PCOS women and matched controls. This was a case-control study conducted at a tertiary University Hospital. We studied 53 PCOS women and 53 healthy matched volunteers as controls. The previously reported parameters were assessed using color Doppler ultrasonography. HR, IMT in the CCA, and peak systolic velocity in all examined arteries were significantly increased in PCOS women compared to controls. On the contrary, DCCA was significantly decreased in PCOS women compared to controls. End diastolic velocity (EDV) in both VA and RA, in the AO and in the left extracranial carotid system was significantly increased in the PCOS group compared to controls. Furthermore, the peripheral resistance (PR) of AO and right external carotid artery was also found to be increased while in both RA and in left VA, PR was decreased. No further statistical significant HA in EDV and PR were noted. The results of this study provide evidence for a mild hyperdynamic circulation in young, normotensive, non-obese women with PCOS compared to controls, indicating a mild sympathetic activation at an early age, which may be an underlying cause of hypertension and cardiovascular risk.

Clinical practice guidelines proposed by the Hellenic Foundation of Osteoporosis for the management of osteoporosis based on DXA results.

In recent years guidelines for the testing and treatment of osteoporotic patients have been published by recognised organisations, including the World Health Organisation (WHO), the National Osteoporosis Foundation (NOF) and the International Osteoporosis Foundation (IOF). Dual Energy X-ray Absorptiometry (DXA) has been considered the technique of choice because of its excellent precision and ability to predict osteoporotic fractures. Last December, based on the Appraisal of the Guidelines for Research and Evaluation (AGREE), the Hellenic Foundation of Osteoporosis, in collaboration with other scientific societies, provided guidelines for the use of DXA for the diagnosis, monitoring and treatment of osteoporosis and Quality Assurance (QA) of these systems. According to these guidelines, the adequacy of the present number of DXA units in Greece was assessed. There are 367 DXA units in Greece, and almost 50% are located in the capital city, Athens, where 34.1% of the population lives. The distribution of DXA devices per resident in the Greek provinces (except Attica) is between 4.2 units/100,000 heads (Ionian Islands) and 1.6 units/100,000 heads (Sterea Hellas). These guidelines have resulted in a suggestive yearly repeat of the measurements, to ensure the precision of the method, but mainly for reasons of compliance. Finally, these guidelines are viewed as a work in progress and will be updated periodically in response to advances in this field.