Current Issue : October - December Volume : 2015 Issue Number : 4 Articles : 8 Articles
Background: Recent advances in bronchoscopy, such as transbronchial biopsy (TBB) using endobronchial\nultrasonography with a guide sheath (EBUS-GS), have improved the diagnostic yield of small-sized peripheral lung\nlesions. In some cases, however, it is difficult to obtain adequate biopsy samples for pathological diagnosis.\nAdequate prediction of the diagnostic accuracy of TBB with EBUS-GS is important before deciding whether\nbronchoscopy should be performed.\nMethods: We retrospectively reviewed 149 consecutive patients who underwent TBB with EBUS-GS for small-sized\nperipheral lung lesions (?30 mm in diameter) from April 2012 to March 2013. We conducted an exploratory\nanalysis to identify clinical factors that can predict an accurate diagnosis by TBB with EBUS-GS. All patients\nunderwent thin-section chest computed tomography (CT) scans (0.5-mm slices), and the CT bronchus sign was\nevaluated before bronchoscopy in a group discussion. The final diagnoses were pathologically or clinically\nconfirmed in all studied patients (malignant lesions, 110 patients; benign lesions, 39 patients).\nResults: The total diagnostic yield in this study was 72.5 % (95 % confidence interval: 64.8ââ?¬â??79.0 %). Lesion size,\nlesion visibility on chest X-ray, and classification of the CT bronchus sign were factors significantly associated with\nthe definitive biopsy result in the univariate analysis. In the multivariate analysis, only the CT bronchus sign\nremained as a significant predictive factor for successful bronchoscopic diagnosis. The CT bronchus sign was also\nsignificantly associated with the EBUS findings of the lesions.\nConclusion: Our results suggest that the CT bronchus sign is a powerful predictive factor for successful TBB with\nEBUS-GS....
Background: In children, septic arthritis (SA) of the hip is either primary or concomitant with acute haematogenous\nosteomyelitis (AHO). However, seldom, patients with isolated SA at presentation, may later show osteomyelitis in the\nmetaphysis. The aim of this study was to elaborate a physiopathological hypothesis based on the peculiar MRI findings\nto explain the onset of AHO after SA.\nMethods: Cases of acute infection of the hip admitted between January 2010 and December 2013 were retrospectively\nreviewed to assess radiographic and MRI features, as well as bacteriological findings. Only children with isolated SA were\nincluded in this study, whereas cases of concomitant SA and AHO at presentation were excluded.\nResults: Ten patients met the inclusion criteria. Six (1ââ?¬â??11 months) demonstrated, on the initial MRI, decreased perfusion\non gadolinium enhanced fat-suppressed T1-weighted sequence of the femoral epiphysis and developed one month\nlater metaphyseal AHO. Four (5ââ?¬â??14 years) did not show decreased perfusion and did not develop AHO on follow-up.\nThe type of germ involved influenced neither the type of enhancement pattern nor the outcome.\nConclusions: Age under one year and decreased perfusion of the affected femoral epiphysis increases the risk of\nsecondary AHO. Our study is the first report in human medicine supporting the physiopathological hypothesis\ndescribed by Alderson et al. in an animal model: primary infection can originally affect the joint, then penetrate\nthe epiphyseal cartilage, and finally spread into the metaphyseal region through transphyseal vessels present only\nin the first 12/18 months of life....
Background: Hepatocellular carcinoma (HCC) remains a global health problem with unique diagnostic and\ntherapeutic challenges, including difficulties in identifying the highest risk patients. Previous work from our lab\nhas established the murine multidrug resistance-2 mouse (MDR2) model of HCC as a reasonable preclinical\nmodel that parallels the changes seen in human inflammatory associated HCC. The purpose of this study is to\nevaluate modalities of PET/CT in MDR2?/? mice in order to facilitate therapeutic translational studies from bench\nto bedside.\nMethods: 18F-FDG and 11C-acetate PET/CT was performed on 12 m MDR2?/? mice (n = 3/tracer) with HCC and 12 m\nMDR2?/+ control mice (n = 3/tracer) without HCC. To compare PET/CT to biological markers of HCC and cellular\nfunction, serum alpha-fetoprotein (AFP), lysophosphatidic acid (LPA), cAMP and hepatic tumor necrosis factor ?\n(TNF?) were quantified in 3-12 m MDR2?/? (n = 10) mice using commercially available ELISA analysis. To translate\nresults in mice to patients 11C-acetate PET/CT was also performed in 8 patents suspected of HCC recurrence following\ntreatment and currently on the liver transplant wait list.\nResults: Hepatic18F-FDG metabolism was not significantly increased in MDR2?/? mice. In contrast, hepatic 11C-acetate\nmetabolism was significantly elevated in MDR2?/? mice when compared to MDR2?/+ controls. Serum AFP and LPA\nlevels increased in MDR2?/? mice contemporaneous with the emergence of HCC. This was accompanied by a\nsignificant decrease in serum cAMP levels and an increase in hepatic TNF?. In patients suspected of HCC recurrence\nthere were 5 true positives, 2 true negatives and 1 suspected false 11C-acetate negative.\nConclusions: Hepatic 11C-acetate PET/CT tracks well with HCC in MDR2?/? mice and patients with underlying liver\ndisease. Consequently 11C-acetate PET/CT is well suited to study 1) HCC emergence/progression in patients and\n2) reduce animal numbers required to study new chemotherapeutics in murine models of HCC....
Background: The diagnosis of hip pain after total hip replacement (THR) represents a highly challenging question\nthat is of increasing concern to orthopedic surgeons. This retrospective study assesses bone scintigraphy with\nHybrid SPECT/CT for the diagnosis of painful THR in a selected cohort of patients.\nMethods: Bone SPECT/CT datasets of 23 patients (mean age 68.9 years) with a painful hip after THR were\nevaluated. Selection of the patients required an inconclusive radiograph, normal serum levels of inflammatory\nparameters (CRP and ESR) or a negative aspiration of the hip joint prior to the examination. The standard of\nreference was established by an interdisciplinary adjudication-panel using all imaging data and clinical follow-up\ndata (>12 month). Pathological and physiological uptake patterns were defined and applied.\nResults: The cause of pain in this study group could be determined in 18 out of 23 cases. Reasons were aseptic\nloosening (n = 5), spine-related (n = 5), heterotopic ossification (n = 5), neuronal (n = 1), septic loosening (n = 1) and\nperiprosthetic stress fracture (n = 1). In (n = 5) cases the cause of hip pain could not be identified. SPECT/CT imaging\ncorrectly identified the cause of pain in (n = 13) cases, in which the integrated CT-information led to the correct\ndiagnosis in (n = 4) cases, mainly through superior anatomic correlation. Loosening was correctly assessed in all\ncases with a definite diagnosis.\nConclusions: SPECT/CT of THA reliably detects or rules out loosening and provides valuable information about\nheterotopic ossifications. Furthermore differential diagnoses may be detected with a whole-body scan and mechanical\nor osseous failure is covered by CT-imaging. SPECT/CT holds great potential for imaging-based assessment of\npainful prostheses....
Background: Alveolar macrophages, with their high functional plasticity, were reported to orchestrate the induction\nand resolution of inflammatory processes in chronic pulmonary diseases. Noninvasive imaging modalities that offer\nsimultaneous monitoring of inflammation progression and tracking of macrophages subpopulations involved in the\ninflammatory cascade, can provide an ideal and specific diagnostic tool to visualize the action mechanism in its\ninitial stages. Therefore, the purpose of the current study was to evaluate the role of M1 and M2 macrophages in\nthe resolution of lipopolysaccharide (LPS)-induced lung inflammation and monitor this process using noninvasive\nfree-breathing MRI and CT protocols.\nMethods: Bone-marrow derived macrophages were first polarized to M1 and M2 macrophages and then labeled with\nsuperparamagnetic iron oxide nanoparticles. BALB/c mice with lung inflammation received an intrapulmonary instillation\nof these ex vivo polarized M1 or M2 macrophages. The biodistribution of macrophages subpopulations and the\nsubsequent resolution of lung inflammation were noninvasively monitored using MRI and micro-CT. Confirmatory\nimmunohistochemistry analyses were performed on lung tissue sections using specific macrophage markers.\nResults: As expected, large inflammatory areas noninvasively imaged using pulmonary MR and micro-CT were observed\nwithin the lungs following LPS challenge. Subsequent intrapulmonary administration of M1 and M2 macrophages\nresulted in a significant decrease in inflammation starting from 72 h. Confirmatory immunohistochemistry analyses\nestablished a progression of lung inflammation with LPS and its subsequent reduction with both macrophages subsets.\nAn enhanced resolution of inflammation was observed with M2 macrophages compared to M1.\nConclusions: The current study demonstrated that ex vivo polarized macrophages decreased LPS-induced lung\ninflammation. Noninvasive free-breathing MR and CT imaging protocols enabled efficient monitoring of progression\nand resolution of lung inflammation....
Background: Osteoporosis is defined as a skeletal disorder characterized by compromised bone strength due to a\nreduction of bone mass and deterioration of bone microstructure predisposing an individual to an increased risk\nof fracture. Trabecular bone microstructure analysis and finite element models (FEM) have shown to improve the\nprediction of bone strength beyond bone mineral density (BMD) measurements. These computational methods\nhave been developed and validated in specimens preserved in formalin solution or by freezing. However, little\nis known about the effects of preservation on trabecular bone microstructure and FEM. The purpose of this\nobservational study was to investigate the effects of preservation on trabecular bone microstructure and FEM in\nhuman vertebrae.\nMethods: Four thoracic vertebrae were harvested from each of three fresh human cadavers (n = 12). Multi-detector\ncomputed tomography (MDCT) images were obtained at baseline, 3 and 6 month follow-up. In the intervals between\nMDCT imaging, two vertebrae from each donor were formalin-fixed and frozen, respectively. BMD, trabecular bone\nmicrostructure parameters (histomorphometry and fractal dimension), and FEM-based apparent compressive modulus\n(ACM) were determined in the MDCT images and validated by mechanical testing to failure of the vertebrae after\n6 months.\nResults: Changes of BMD, trabecular bone microstructure parameters, and FEM-based ACM in formalin-fixed and\nfrozen vertebrae over 6 months ranged between 1.0ââ?¬â??5.6 % and 1.3ââ?¬â??6.1 %, respectively, and were not statistically\nsignificant (p > 0.05). BMD, trabecular bone microstructure parameters, and FEM-based ACM as assessed at baseline,\n3 and 6 month follow-up correlated significantly with mechanically determined failure load (r = 0.89ââ?¬â??0.99; p < 0.05).\nThe correlation coefficients r were not significantly different for the two preservation methods (p > 0.05).\nConclusions: Formalin fixation and freezing up to six months showed no significant effects on trabecular bone\nmicrostructure and FEM-based ACM in human vertebrae and may both be used in corresponding in-vitro experiments\nin the context of osteoporosis....
Background: Pancreatic cancer accompanied by a moderate-sized pseudocyst with extrapancreatic growth is\nextremely rare. Diagnosis of pancreatic cancer on preoperative imaging is difficult when the pancreatic parenchyma is\ncompressed by a pseudocyst and becomes unclear. Despite advances in imaging techniques, accurate preoperative\ndiagnosis of cystic lesions of the pancreas remains difficult. In this case, it was challenging to diagnose pancreatic\ncancer preoperatively as we could not accurately assess the pancreatic parenchyma, which had been compressed by a\nmoderate-sized cystic lesion with extrapancreatic growth.\nCase presentation: A 63-year-old woman underwent investigations for epigastric abdominal pain. She had no history\nof pancreatitis. Although we suspected pancreatic ductal carcinoma with a pancreatic cyst, there was no mass lesion or\nlow-density area suggestive of pancreatic cancer. We did not immediately suspect pancreatic cancer, as development\nof a moderate-sized cyst with extrapancreatic growth is extremely rare and known tumor markers were not elevated.\nTherefore, we initially suspected that a massive benign cyst (mucinous cyst neoplasm, serous cyst neoplasm, or\nintraductal papillary mucinous neoplasm) resulted in stenosis of the main pancreatic duct. We were unable to\nreach a definitive diagnosis prior to the operation. We had planned a pancreaticoduodenectomy to reach a\ndefinitive diagnosis. However, we could not remove the tumor because of significant invasion of the surrounding\ntissue (portal vein, superior mesenteric vein, etc.). The fluid content of the cyst was serous, and aspiration\ncytology from the pancreatic cyst was Class III (no malignancy), but the surrounding white connective tissue\nsamples were positive for pancreatic adenocarcinoma on pathological examination during surgery. We repeated\nimaging (CT, MRI, endoscopic ultrasound, etc.) postoperatively, but there were neither mass lesions nor a\nlow-density area suggestive of pancreatic cancer. In retrospect, we think that the slight pancreatic duct dilation\nwas the only finding suggestive of pancreatic cancer.\nConclusions: It is difficult to diagnose pancreatic cancer with pseudocyst preoperatively. If a pancreatic cyst is\nfound in patients who had normal tumor marker levels or no history of pancreatitis, we should always consider\nthe possibility of pancreatic cancer. In such cases, slight pancreatic duct dilation may be a diagnostic clue....
Background: Respiratory gating is often used in 4D-flow acquisition to reduce motion artifacts. However, gating\nincreases scan time. The aim of this study was to investigate if respiratory gating can be excluded from 4D flow\nacquisitions without affecting quantitative intracardiac parameters.\nMethods: Eight volunteers underwent CMR at 1.5 T with a 5-channel coil (5ch). Imaging included 2D flow\nmeasurements and whole-heart 4D flow with and without respiratory gating (Resp(+), Resp(?)). Stroke volume\n(SV), particle-trace volumes, kinetic energy, and vortex-ring volume were obtained from 4D flow-data. These parameters\nwere compared between 5ch Resp(+) and 5ch Resp(?). In addition, 20 patients with heart failure were scanned using a\n32-channel coil (32ch), and particle-trace volumes were compared to planimetric SV. Paired comparisons were performed\nusing Wilcoxonâ��s test and correlation analysis using Pearson r. Agreement was assessed as bias �± SD.\nResults: Stroke volume from 4D flow was lower compared to 2D flow both with and without respiratory gating\n(5ch Resp(+) 88 �± 18 vs 97 �± 24.0, p = 0.001; 5ch Resp(?) 86 �± 16 vs 97.1 �± 22.7, p < 0.01). There was a good correlation\nbetween Resp(+) and Resp(?) for particle-trace derived volumes (R2 = 0.82, 0.2 �± 9.4 ml), mean kinetic energy (R2 = 0.86,\n0.07 �± 0.21 mJ), peak kinetic energy (R2 = 0.88, 0.14 �± 0.77 mJ), and vortex-ring volume (R2 = 0.70, ?2.5 �± 9.4 ml).\nFurthermore, good correlation was found between particle-trace volume and planimetric SV in patients for 32ch\nResp(?) (R2 = 0.62, ?4.2 �± 17.6 ml) and in healthy volunteers for 5ch Resp(+) (R2 = 0.89, ?11 �± 7 ml), and 5ch Resp(?)\n(R2 = 0.93, ?7.5 �± 5.4 ml), Average scan duration for Resp(?) was shorter compared to Resp(+) (27 �± 9 min vs 61 �±\n19 min, p < 0.05).\nConclusions: Whole-heart 4D flow can be acquired with preserved quantitative results without respiratory gating,\nfacilitating clinical use....
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