Acute posterior leukoencephalopathy in a patient with nephrotic syndrome

 Reversible posterior leukoencephalopathy syndrome is one of the most serious complications of immunosuppressive therapy. The clinical features include headache, altered mental functioning, seizures, cortical blindness and other visual disturbances, with hypertension. The neuroimaging studies reveal predominant posterior leukoencephalopathy. Usually, antihypertensive therapy and reduction or withdrawal of immunosuppressive agents have been reported to resolve the neurological deficits and imaging abnormalities within a few weeks. We discuss here a 51-year-old woman with nephrotic syndrome who developed acute leukoencephalopathy during combination therapy with prednisolone and cyclosporine. She developed severe headache, visual disturbance, consciousness disturbance, and generalized tonic clonic convulsion. A computed tomography scan (CT) revealed low-density areas in the subcortices of the parietal and occipital lobes. Magnetic resonance imaging (MRI) disclosed a high signal intensity area on T₂-weighted images and a low signal intensity area on T₁-weighted images in the same lesions. Follow-up brain CT and MRI were performed several times. Three weeks after the first study, these lesions had completely resolved, but she had persistent altered consciousness for more than 1 year. Received: April 3, 2002 / Accepted: October 29, 2002 Correspondence to:K. Utsumi     

Imaging of multiple myeloma: Current concepts

Medical imaging is of crucial importance for diagnosis and initial staging as well as for differentiation of multiple myeloma (MM) from other monoclonal plasma cell diseases. Conventional radiography represents the reference standard for diagnosis of MM due to its wide availability and low costs despite its known limitations such as low sensitivity, limited specificity and its inability to detect extraosseous lesions. Besides conventional radiography, newer cross-sectional imaging modalities such as whole-body low-dose computed tomography (CT), whole-body magnetic resonance imaging (MRI) and ¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/CT are available for the diagnosis of osseous and extraosseous manifestations of MM. Whole-body low-dose CT is used increasingly, replacing conventional radiography at selected centers, due to its higher sensitivity for the detection of osseous lesions and its ability to diagnose extraosseous lesions. The highest sensitivity for both detection of bone marrow disease and extraosseous lesions can be achieved with whole-body MRI and ¹⁸F-FDG PET/CT. According to current evidence, MRI is the most sensitive method for initial staging while ¹⁸F-FDG PET/CT allows monitoring of treatment of MM. There is an evolving role for assessment of treatment response using newer MR imaging techniques. Future studies are needed to further define the exact role of the different imaging modalities for individual risk stratification and therapy monitoring.     

Magnetic resonance imaging (MRI): Method and early clinical experiences in diseases of the central nervous system

Summary Magnetic resonance imaging (MRI) has undergone a rapid development which is still continuing. In this article a survey is given of the present status of this new diagnostic tool in the evaluation of diseases of the central nervous system.When atoms with uneven numbers of protons or neutrons in a homogeneous magnetic field are tilted against the main vector of this field by a radiofrequency pulse, nuclear magnetic resonance can be observed. During the relaxation of the little dipoles back to the direction of the underlying magnetic field, a resonance signal is generated. The superposition of variable field gradients enables the scanning of sectional images in the axial, frontal and sagittal plane.The variables of H⁺-magnetic resonance which can be utilized for imaging are: the proton density, the relaxation times T₁ (spin-lattice) and T₂ (spin-spin) and flow effects. While the proton density in organic tissue fluctuates only by some 10%, the relaxation times may vary by several hundred per cent. Tissue contrast, therefore, is mainly based on relaxation times differences. The image character can also be influenced by variations of imaging parameters (i.e. repetition rate, interpulse delay, read out or echo delay) in different imaging sequences, such as the spin-echo and the inversion recovery technique. Depending on these imaging parameters T₁ and T₂ will contribute to the signal to a varying degree. This fact is most important for the diagnostic information of MRI.In initial clinical experiences in the diagnosis of diseases of the central nervous system, MRI has demonstrated high sensitivity in the detection of lesions (such as oedema, neoplasms, demyelinating disease), but less significance in lesion discrimination.In spinal disease the direct sagittal imaging of MRI enables MRI-myelography without contrast medium, superior to conventional myelography in many cases. For detailed evaluation of disc disease, however, the spatial resolution still has to be improved.Promising results have been obtained from flow effects. Depending on the flow velocity of blood, vessels appear white with intensive signals (slow flow) or black due to low signal intensities (rapid flow). MRI-angiography including measurement of blood flow seems possible.MRI-contrast media are not yet available for routine clinical use. Promising results have been reported on the basis of rare-earth elements, such as gadolinium Gd³⁺. These substances decrease T₁ and T₂ with subsequent increase in signal intensity.Concerning harmful side-effects of MRI, three possible sources have to be considered: the static magnetic field, the changing magnetic field, and radiofrequency heating. No permanent damage to organisms has been described up to the present time, in relation to the magnetic field strength used in MRI. However, there is known risk for patients who carry cardiac pace makers or metal implants such as aneurysm clips.     

Bone metastasis imaging with SPECT/CT/MRI: A preclinical toolbox for therapy studies

Bone is one of the most common metastatic target sites in breast cancer, with more than 200 thousand new cases of invasive cancer diagnosed in the US alone in 2011. We set out to establish a multimodality imaging platform for bone metastases in small animals as a tool to non-invasively quantify metastasis growth, imaging the ensuing bone lesions and possibly the response to treatment. To this end, a mouse model of osteolytic metastatic bone tumors was characterized with SPECT/CT and MRI over time. A cell line capable of forming bone metastases, MDA-MB-231, was genetically modified to stably express the reporter gene herpes simplex virus-1 thymidine kinase (hsv-1 tk). The intracellular accumulation of the radiolabeled tracer [¹²³I]FIAU promoted by HSV-1 TK specifically pinpoints the location of tumor cells which can be imaged in vivo by SPECT.First, a study using tumors implanted subcutaneously was performed. The SPECT/MRI overlays and the ex vivo γ-counting showed a linear correlation in terms of %ID/cm³ (R² = 0.93) and %ID/g (R² = 0.77), respectively. Then, bone metastasis growth was imaged weekly by SPECT/CT and T₂-weighted MRI over a maximum of 40 days post-intracardiac injection of tumor cells. The first activity spots detectable with SPECT, around day 20 post-cell injection, were smaller than 2 mm³ and not yet visible by MRI and increased in volume and in %ID over the weeks. Osteolytic bone lesions were visible by CT (in vivo) and μCT (ex vivo). The SPECT/MRI overlays also showed a linear correlation in terms of %ID/cm³ (R² = 0.86).In conclusion, a new multimodality imaging platform has been established that non-invasively combines images of active tumor areas (SPECT), tumor volume (MRI) and the corresponding bone lesions (CT and μCT). To our knowledge this is the first report where the combination of soft tissue information from MRI, bone lesions by CT, and reporter gene imaging by SPECT is used to non-invasively follow metastatic bone lesions.     

胸椎肋骨横突螺钉技术的CT影像解剖学参数研究

目的通过影像学测量对胸椎肋骨横突螺钉技术解剖学参数进行分析,为该技术的临床应用提供参考。方法选取100名健康成年志愿者T_(1～10)胸椎肋骨结合区的CT图像,应用PACS软件分别测量每个椎体相应横突模拟进钉点(A点和B点)在横断位上的肋骨横突长(CL)、肋骨横突宽(CW)以及最大内倾角(MIA)和极限外展角(UEA),其中A点为横突背侧肋骨横突关节表面,B点为横突背侧最内侧缘。结果 A点CL最大值均位于T_6节段,最小值位于T_1节段,以T_6节段为分界点呈先增大后减小的变化趋势;B点CL较为平稳。A、B点CW最大值均位于T_1节段,最小值位于T_6节段,以T_6节段为分界点呈先减小后增大的变化趋势。A点MIA最大值位于T_6节段,最小值位于T_1节段,以T_6节段为分界点基本表现为先增大后减小的变化趋势;B点MIA较为平稳。A点UEA从T_1节段到T_(10)节段逐渐减小,B点UEA则从T_1节段到T_(10)节段逐渐增大。结论本研究设计的2个胸椎肋骨横突螺钉进钉点的解剖学参数有不同特点,可为胸椎肋骨横突螺钉固定技术的临床应用提供参考。     

Highly variable biodistribution of 68Ga labeled somatostatin analogues 68Ga-DOTA-NOC and 68Ga-DOTA-TATE in neuroendocrine tumors: clinical implications for somatostatin receptor directed PET/CT

BackgroundSomatostatin receptor (SSTR)-targeted positron emission tomography/computed tomography (PET/CT) imaging has risen to the forefront for neuroendocrine tumor (NET) detection and management, yet the variability of significant uptake variability (SUV) as a semiquantitative measure of disease detection and tumor response to treatment has not been fully explored.MethodsWe assess the reproducibility and interscan variability of SUV metrics of normal tissue and NET in serial ⁶⁸Ga-DOTA-NOC and ⁶⁸Ga-DOTA-TATE PET imaging to clinically monitor disease state. Eighty-one patients were enrolled in this retrospective study.ResultsBoth primary and metastatic hepatic lesions demonstrated SUV (SUV_mean 16.5±8.0). The median SUV_mean was 16 for the spleen, 9.7 for the pituitary, 12.6 for the adrenal glands, and 4.8 for the liver. The normal pituitary gland demonstrates focal homogenous uptake with SUV_max range of 4.5–23. The adrenal gland showed uptake with SUV_max range of 4.1–29.4, which is more than two times greater than liver uptake (SUV_mean range, 2.3–12.4). Highest physiological uptake seen in the spleen (average SUV_mean of 17.3, range of 5.4–34.4).ConclusionsThe highly variable nature of regional SUV_mean and SUV_max in both physiologic tissue and lesions suggests the need for incorporation of more reliable quantitative measures for clinical decision making.     

Magnetic Resonance Imaging Findings Predict the Recurrence of Chronic Subdural Hematoma

The exact predictive factors for postoperative recurrence of chronic subdural hematoma (CSDH) are still unknown. Based on the preoperative magnetic resonance imaging (MRI), low recurrence rate of T₁-hyperintensity hematoma was previously reported. We investigated the other types of radiological findings which are related to the recurrence rate of CSDH in large number of patients analyzed by multivariate logistic regression model. Preoperative MRI and postoperative computed tomography (CT) were performed and the influence of the preoperative use of antiplatelet or anticoagulant drugs was also studied. The overall recurrence rate was 9.3% (47 of 505 hematomas). The MRI T₁-iso/hypointensity group showed a significantly higher recurrence rate (18.2%, 29 of 159) compared to the other groups (5.2%, 18 of 346; p < 0.001). Multivariate logistic regression analysis showed T₁ classification was the solo significant prognostic predictor among various factors such as bilateral hematoma, antiplatelet or anticoagulant drug usage, residual hematoma on postoperative CT, and MRI classification (p < 0.001): adjusted odds ratio for the recurrence in T₁-iso/hypointensity group relative to the T₁-hyperintensity group was 5.58 [95% confidence interval (CI), 2.09–14.86] (p = 0.001). Postoperative residual hematoma and antiplatelet or anticoagulant drug usage did not increase the recurrence risk. The preoperative MRI findings, especially T₁WI findings, have predictive value for postoperative recurrence of CSDH and the T₁-iso/hypointensity group can be assumed to be a high recurrence risk group.     

Evaluation of articular cartilage with quantitative MRI in an equine model of post‐traumatic osteoarthritis

Chondral lesions lead to degenerative changes in the surrounding cartilage tissue, increasing the risk of developing post‐traumatic osteoarthritis (PTOA). This study aimed to investigate the feasibility of quantitative magnetic resonance imaging (qMRI) for evaluation of articular cartilage in PTOA. Articular explants containing surgically induced and repaired chondral lesions were obtained from the stifle joints of seven Shetland ponies (14 samples). Three age‐matched nonoperated ponies served as controls (six samples). The samples were imaged at 9.4 T. The measured qMRI parameters included T₁, T₂, continuous‐wave T_1ρ (CWT_1ρ), adiabatic T_1ρ (AdT_1ρ), and T_2ρ (AdT_2ρ) and relaxation along a fictitious field (T_RAFF). For reference, cartilage equilibrium and dynamic moduli, proteoglycan content and collagen fiber orientation were determined. Mean values and profiles from full‐thickness cartilage regions of interest, at increasing distances from the lesions, were used to compare experimental against control and to correlate qMRI with the references. Significant alterations were detected by qMRI parameters, including prolonged T₁, CWT_1ρ, and AdT_1ρ in the regions adjacent to the lesions. The changes were confirmed by the reference methods. CWT_1ρ was more strongly associated with the reference measurements and prolonged in the affected regions at lower spin‐locking amplitudes. Moderate to strong correlations were found between all qMRI parameters and the reference parameters (ρ = ?0.531 to ?0.757). T₁, low spin‐lock amplitude CWT_1ρ, and AdT_1ρ were most responsive to changes in visually intact cartilage adjacent to the lesions. In the context of PTOA, these findings highlight the potential of T₁, CWT_1ρ, and AdT_1ρ in evaluation of compositional and structural changes in cartilage.     

Cranial magnetic resonance imaging in multiple sclerosis — indicated only in exceptional cases?

Clinical examination, spinal fluid laboratory data, evoked potentials (EP), cranial computed tomography (CT), and magnetic resonance imaging (MRI) were compared for their value in diagnosing multiple sclerosis (MS) in 51 patients aged 18–60 yrs.MRI was superior to CT imaging: supratentorial lesions were found in 90% of the patients with confirmed MS. These lesions are not specific, however, as vascular processes, vitamin B₁₂ deficiency or chronic encephalitis, can show similar MRI-patterns. The detection of infratentorial lesions in symptomatic patients was poor (8% compared to 64% pathological EP-findings). Thirty-eight patients (= 75%) could be classified correctly as confirmed MS according toBauer-criteria without any CT or MR imaging. In the remaining 13 patients presenting classificatory problems due to normal CSF, first manifestation or possible alternate processes, MRI helped for the final diagnosis in only 6 cases.The value of MRI in diagnosing MS seems to lie in its superiority to CT in excluding other pathological processes or for research rather than in its value for the confirmation of the diagnosis. In a minority of cases, it can detect supratentorial lesions in patients with pure spinal symptoms, normal CSF, or first manifestations.     

Validity of Computerized Tomography in Blunt Renal Trauma

PurposeImproved imaging techniques and new therapeutic possibilities require rethinking the indication for laparotomy with regard to blunt renal trauma. Refined classification systems would facilitate the decision relating to therapy but they are based on knowledge of the imaging accuracy of computerized tomography (CT). We evaluated the validity of the CT depiction of renal injuries.Materials and MethodsA total of 42 porcine kidneys were subjected to traumatization of various degrees. They then underwent CT examination and were subsequently cross-dissected into slices 3 mm thick. The comparative evaluation involved 2,080 CT images and 1,819 macroscopic sectional views, which showed 3,521 and 3,778 individual lesions, respectively.ResultsUsing CT the overall extent of injury in renal trauma was only slightly overrated at an average of 15% higher than that seen on macroscopy. Simple linear lesions tended to be over assessed and parenchymal destruction tended to be under assessed. Central lesions were depicted more frequently than peripheral lesions. CT of medullary lesions and parenchymal detachment was not feasible.ConclusionsCT of the kidney enables the distinction of different kinds of lesions and their localization well. Pelvic structures or vessels can imitate linear lesions. However, this imaging procedure can be used as a basis for refining categorization systems for blunt renal trauma. It can also be used to obtain a large quantity of lesion data for biomechanical investigations.     

The role of bone marrow edema on osteochondral lesions of the talus

Background

To assess the functional and radiological outcomes after arthroscopic talus autologous matrix-induced chondrogenesis (AT-AMIC^®) in 2 groups: patients with and without bone marrow edema (BME).

Magnetic resonance imaging of the sella turcica and parasellar region. A clinical-radiographic evaluation with computed tomography

Thirty-one magnetic resonance (MR) scans and computed tomography (CT) scans were obtained on 25 patients in whom lesions involving the sella turcica or parasellar region were clinically suspected. Surgical pathologic studies were available in 19 cases. Twenty-two of the MR scans were of diagnostic value equivalent to that of the corresponding CT studies. In two small meningiomas, an empty sella, and a sphenoid-middle fossa tumor, MR technology failed to delineate the pathologic process adequately. In the remaining five patients, MR either more convincingly demonstrated the pathologic anatomy or yielded diagnostic information not present in the CT study. In view of the absence of ionizing radiation, high degree of tissue contrast and spatial resolution, and multiplanar capability, magnetic resonance scanning will probably become the initial imaging modality of choice in patients suspected of harboring sellar and parasellar tumors.     

Nuclear magnetic resonance imaging: Review of early clinical experience

Nuclear magnetic resonance tomography is a powerful new imaging modality which produces cross-sectional images similar to those obtained by computerized tomography. However, unlike computerized tomography, nuclear magnetic resonance imaging does not use ionizing radiation but rather utilizes an apparently safe interaction between magnetic fields, radio waves, and atomic nuclei. Basic principles of nuclear magnetic resonance imaging are discussed briefly and promising early clinical applications are reviewed.The two magnetic relaxation times, T₁ and T₂, provide discrimination between tissues based on differences in fat and water content. Tumors are readily differentiated from normal tissue on the basis of the increased water content, primarily due to edema and hypervascularity. Although nuclear magnetic resonance imaging is very sensitive in the detection of these abnormalities, it is not yet able to provide a specific diagnosis.     

脊柱胸腰段骨折椎体的三维形态学分析

目的 通过三维骨折线分布图的大数据形态学分析,揭示脊柱胸腰段椎体（T₁₁~L₂）骨折的好发模式及骨折特点,从而指导临床决策。方法 回顾性分析2017年1月至2019年3月AO分型为A型的压缩性胸腰段椎体（T₁₁~L₂）骨折病人的临床资料。共纳入了257例研究对象,平均年龄为46岁,266个骨折椎体,其中T₁₁骨折15例,T₁₂骨折69例,L₁骨折95例,L₂骨折87例。把病人高分辨率CT数据导入到Mimics软件中,通过阈值分割,重建出骨折椎体模型。依次将各个骨折椎体的骨折线临摹到相应正常椎体模型上,获得各个椎体节段的3D骨折线分布图。结果 3D骨折线分布图揭示骨折线主要集中在椎体的上半部分以及椎体的外1/3部分,并且沿着椎体的前方和侧方呈环状楔形分布。结论 首次将骨折的Mapping技术应用到胸腰段骨折的分析研究中,骨折线分布图揭示了胸腰段骨折的好发模式及形态学特点,从流行病学及形态学方面提高了对胸腰段骨折的认识,有助于提升后续的科学研究及改善临床决策。     

Incidence and outcomes of incidental breast lesions detected on cross‐sectional imaging examinations

The aim of this study was to determine the frequency and outcomes of incidental breast lesions detected on nonbreast specific cross‐sectional imaging examinations. A retrospective review of the medical records was performed to identify all patients without a known history of breast cancer, who had an incidentally discovered breast lesion detected on a nonbreast imaging examination performed at our institution between September 2008 and August 2012 for this IRB‐approved, HIPAA compliant study. Outcomes of the incidental lesions were determined by follow‐up with dedicated breast imaging (mammography, breast ultrasound, and/or breast MRI) or results of biopsy, if performed. Imaging modality of detection, imaging features, patient age, patient location at the time of the nonbreast imaging examination, type of follow‐up, and final outcome were recorded. Rates of malignancy were also calculated, and comparison was made across the different cross‐sectional imaging modalities. Kruskal‐Wallis and Fisher's exact tests were used to identify factors associated with an increased rate of malignancy. Logistic regression was used to model the risk of malignancy as a function of continuous predictors (such as patient age or lesion size); odds ratios and 95% confidence intervals were obtained. A total of 292 patients with incidental breast lesions were identified, 242 of whom had incidental lesions were noted on computed tomography (CT) studies, 25 on magnetic resonance imaging (MRI), and 25 on positron emission tomography (PET). Although most of the incidental breast lesions were detected on CT examinations, PET studies had the highest rate of detection of incidental breast lesions per number of studies performed (rate of incidental breast lesion detection on PET studies was 0.29%, compared to 0.10% for CT and 0.01% for MRI). Of the 121 of 292 (41%) patients who received dedicated breast imaging work‐up at our institution, 40 of 121 (33%) underwent biopsy and 25 of 121 (21%) had malignancy. There was a significantly increased rate of malignancy in older patients (odds ratio: 1.05, 95% CI: 1.02‐1.093; P = .006). Additionally, patients with PET‐detected incidental breast lesions had a significantly higher rate of malignancy (55%), compared to patients with CT‐detected (35%) and MRI‐detected (8%) incidental breast lesions (P = .038). The rate of malignancy upon follow‐up of incidental breast lesions detected on nonbreast imaging examinations in this retrospective study was 21%, supporting the importance of emphasizing further work‐up of all incidentally detected breast lesions with dedicated breast imaging. Additionally, we found that PET examinations had the highest rate of detection of incidental breast lesions and the highest rate of malignancy, which suggests that PET examinations may be more specific for predicting the likelihood of malignancy of incidental breast lesions, compared to CT and MRI.     

Dual-Time <Superscript>18</Superscript>F-FDG PET/CT Imaging in Initial Locoregional Staging of Breast Carcinoma: Comparison with Conventional Imaging and Pathological Prognostic Factors

The aims of this retrospective study were to consider the diagnostic role of dual-time ¹⁸F-fluorodeoxyglucose positron emission tomography and computed tomography (¹⁸F-FDG PET/CT) in detection of breast carcinoma and axillary lymph node (ALN) status and to evaluate the primary tumor ¹⁸F-FDG uptake pattern. Preoperative staging was performed by ¹⁸F-FDG PET/CT in 78 female patients with breast carcinoma. Conventional imaging results were evaluated by breast magnetic resonance imaging (MRI) of 79 lesions in 78 patients, bilateral mammography (MMG) of 40 lesions in 40 patients, and breast ultrasonography (USG) of 47 lesions in 46 patients. The primary tumor detection rate using ¹⁸F-FDG PET/CT was higher than those using MRI, USG, and MMG. The sensitivity and specificity of ¹⁸F-FDG PET/CT scans for detecting multifocality were higher than those of MRI. The specificity of ALN metastasis detection with MRI was higher than that with ¹⁸F-FDG PET/CT, but ¹⁸F-FDG PET/CT had higher sensitivity. Higher ¹⁸F-FDG uptake levels were detected in patients with ALN metastasis, histologic grade 3, estrogen–progesterone-negative receptor status, lymphatic invasion, and moderate to poor prognostic groups. There was no statistical difference for the retention index in categorical pathological parameters except for progesterone-negative status. In conclusion, ¹⁸F-FDG PET/CT scans may be a valuable imaging technique for evaluating primary tumor and axillary status in staging breast carcinoma and ¹⁸F-FDG uptake may be a prognostic factor that indicates aggressive tumor biology and poor prognosis. Dual-time imaging in breast carcinoma staging may not be used for predicting pathological criteria and the aggressiveness of primary lesions.     

Increased IL‐6 Expression in Osteoclasts Is Necessary But Not Sufficient for the Development of Paget's Disease of Bone

Measles virus nucleocapsid protein (MVNP) expression in osteoclasts (OCLs) and mutation of the SQSTM1 (p62) gene contribute to the increased OCL activity in Paget's disease (PD). OCLs expressing MVNP display many of the features of PD OCLs. Interleukin‐6 (IL‐6) production is essential for the pagetic phenotype, because transgenic mice with MVNP targeted to OCLs develop pagetic OCLs and lesions, but this phenotype is absent when MVNP mice are bred to IL‐6^–/– mice. In contrast, mutant p62 expression in OCL precursors promotes receptor activator of NF‐κB ligand (RANKL) hyperresponsivity and increased OCL production, but OCLs that form have normal morphology, are not hyperresponsive to 1,25‐dihydroxyvitamin D₃ (1,25‐(OH)₂D₃), nor produce elevated levels of IL‐6. We previously generated p62^P394L knock‐in mice (p62KI) and found that although OCL numbers were increased, the mice did not develop pagetic lesions. However, mice expressing both MVNP and p62KI developed more exuberant pagetic lesions than mice expressing MVNP alone. To examine the role of elevated IL‐6 in PD and determine if MVNP mediates its effects primarily through elevation of IL‐6, we generated transgenic mice that overexpress IL‐6 driven by the tartrate‐resistant acid phosphatase (TRAP) promoter (TIL‐6 mice) and produce IL‐6 at levels comparable to MVNP mice. These were crossed with p62KI mice to determine whether IL‐6 overexpression cooperates with mutant p62 to produce pagetic lesions. OCL precursors from p62KI/TIL‐6 mice formed greater numbers of OCLs than either p62KI or TIL‐6 OCL precursors in response to 1,25‐(OH)₂D₃. Histomorphometric analysis of bones from p62KI/TIL‐6 mice revealed increased OCL numbers per bone surface area compared to wild‐type (WT) mice. However, micro‐quantitative CT (µQCT) analysis did not reveal significant differences between p62KI/TIL‐6 and WT mice, and no pagetic OCLs or lesions were detected in vivo. Thus, increased IL‐6 expression in OCLs from p62KI mice contributes to increased responsivity to 1,25‐(OH)₂D₃ and increased OCL numbers, but is not sufficient to induce Paget's‐like OCLs or bone lesions in vivo. © 2014 American Society for Bone and Mineral Research.     

Severe dysplastic lesions in the colon – how aggressive should we be?

Introduction Biopsies of colonic lesions are often reported as showing dysplasia, though in reality some lesions may harbour invasive malignancy. Aim To assess the risk of underlying invasive malignancy in sessile polyps where biopsies had shown severe dysplasia and also to attempt to define a management strategy in such patients. Methods Between 1997 and 2001, 30 patients were diagnosed as having severe dysplasia using Morson's criteria in colonic lesions not amenable for endoscopic polypectomy. Severely dysplastic lesions were completely excised by appropriate surgical measures. Results Out of 30 patients, 15 had invasive cancers. Surgical intervention involved anterior resections, endoanal excisions, sigmoid colectomies, or abdomino‐perineal excisions as deemed appropriate. The lesions ranged in size from 0.5 cm to 13 cm (mean 3.4 cm). There were nine T₁ lesions (one of which was T₁N₁) and two each of T₂, T₃, T₄ lesions (10 Dukes' A, 3 Dukes' B, 2 Dukes' C). Complete resection was confirmed histologically in all cases. One patient had a leak following endoanal excision, which required intervention. There was no mortality. Discussion This study demonstrates that endoscopic sampling can be misleading and severely dysplastic sessile lesions should be managed along the same principles as followed for invasive cancers, rather than adopting a ‘wait and watch’ policy with repeated endoscopies, biopsies or piece‐meal polypectomies.     

Nuclear magnetic resonance imaging of the prostate

Nuclear magnetic resonance (NMR) imaging of the prostate has been done in 25 patients, using a prototype machine developed in Aberdeen. It is a non-invasive technique which demonstrated the anatomical extent and pathological nature of prostatic lesions. The NMR images in both benign and malignant prostatic disease on this machine are comparable with first generation CT scans.     

Improved detection of juxtacortical lesions using highly accelerated double inversion-recovery MRI in patients with multiple sclerosis

PurposeThe purpose of this study was to compare a highly-accelerated double inversion recovery (fast-DIR) sequence using a recent parallel imaging technique (CAIPIRINHA) with a conventional DIR (conv-DIR) sequence for image quality and the detection of juxtacortical and infratentorial multiple sclerosis (MS) lesions.Materials and methodsA total of 38 patients with MS who underwent brain MRI at 3 T between 2020 and 2021 were included. There were 27 women and 12 men with a mean age of 40 ± 12.8 (standard deviation) years (range: 20–59 years). All patients underwent conv-DIR sequence and fast-DIR sequence. Fast-DIR was obtained with a T₂-preparation module to improve contrast and an iterative denoising algorithm to compensate noise enhancement. Two blinded readers reported the number of juxtacortical and infratentorial MS lesions for fast-DIR and conv-DIR, confirmed by further consensus reading that was used as the standard of reference. Image quality and contrast were evaluated for fast-DIR and conv-DIR sequences. Comparisons between fast-DIR and conv-DIR sequences were performed using Wilcoxon test and Lin concordance correlation coefficient.ResultsThirty-eight patients were analyzed. Fast-DIR imaging allowed detection of 289 juxtacortical lesions vs. 238 with conv-DIR, corresponding to a significant improved detection rate with fast-DIR (P < 0.001). Conversely, 117 infratentorial lesions were detected with conv-DIR sequence vs. 80 with fast-DIR sequence (P < 0.001). Inter-observer agreement for lesion detection with fast-DIR and conv-DIR was very high (Lin concordance correlation coefficient ranging between 0.86 and 0.96).ConclusionFast-DIR improves the detection of juxtacortical MS lesions, but is limited for the detection of infratentorial MS lesions.