Bone texture analysis using CT-simulation scans to individuate risk parameters for radiation-induced insufficiency fractures.

This study deals with the role of texture analysis as a predictive factor of radiation-induced insufficiency fractures in patients undergoing pelvic radiation. INTRODUCTION: This study aims to assess the texture analysis (TA) of computed tomography (CT) simulation scans as a predictive factor of insufficiency fractures (IFs) in patients with pelvic malignancies undergoing radiation therapy (RT). METHODS: We performed an analysis of patients undergoing pelvic RT from January 2010 to December 2014, 24 of whom had developed pelvic bone IFs. We analyzed CT-simulation images using ImageJ macro software and selected two regions of interest (ROIs), which are L5 body and the femoral head. TA parameters included mean (m), standard deviation (SD), skewness (sk), kurtosis (k), entropy (e), and uniformity (u). The IFs patients were compared (1:2 ratio) with controlled patients who had not developed IFs and matched for sex, age, menopausal status, type of tumor, use of chemotherapy, and RT dose. A reliability test of intra- and inter-reader ROI TA reproducibility with the intra-class correlation coefficient (ICC) was performed. Univariate and multivariate analyses (logistic regression) were applied for TA parameters observed both in the IFs and the controlled groups. RESULTS: Inter- and intra-reader ROI TA was highly reproducible (ICC > 0.90). Significant TA parameters on paired t test included L5 m (p = 0.001), SD (p = 0.002), k (p = 0.006), e (p = 0.004), and u (p = 0.015) and femoral head m (p < 0.001) and SD (p = 0.001), whereas on logistic regression analysis, L5 e (p = 0.003) and u (p = 0.010) and femoral head m (p = 0.027), SD (p = 0.015), and sex (p = 0.044). CONCLUSIONS: In our experience, bone CT TA could be correlated to the risk of radiation-induced IFs. Studies on a large patient series and methodological refinements are warranted.

A solitary uterine relapse in T-cell Acute Lymphoblastic Leukaemia: CT features and pathologic correlation.

T-cell Acute Lymphoblastic Leukemia (T-cell ALL) is a rare haematological neoplasia, that affects children and less commonly adults. Female genital tract and particularly uterus involvement in acute ALL is rare. This report presents the CT features of a 64-year-old woman with uterine relapse of T-cell ALL, occurring 11 months after the diagnosis, as a second, unique relapse of disease. The patient was asymptomatic when a CT examination showed a homogenous thickness of the uterine wall in comparison with the previous CT examination. Histology from biopsy specimens, obtained through hysteroscopy, confirmed T-cell ALL localisation (TdT+, CD10+, CD3c+ and CD2+). The uterus could be a site of relapse in patients suffering from ALL. Even though an MRI examination could better demonstrate the disease in cases of suspected female genital tract involvement by ALL, the comparison of differences between a present and a previous CT examination is sufficient to suspect the diagnosis.

Errors in multidetector row computed tomography.

Multidetector row computed tomography (MDCT) represents the technique of choice for the majority of pathologies today and is responsible for the majority of diagnoses. However, despite the low number of studies dedicated to errors in MDCT, CT reporting seems especially prone to generating errors and errors are an inevitable part of MDCT practice. Most of these arise during image interpretation but, differently from other radiological techniques, the awareness of radiologists regarding technical CT aspects and pathologies substantially contribute in generating errors, in particular because CT technology expands rapidly and radiologists do not routinely receive specific and appropriate training for its use and because CT examinations are not the same for each patient and each pathology and the choice of the most appropriate CT examination (including the dose exposure to the patient) presumes a very large awareness from radiologists. This review is aimed at increasing awareness regarding the type of errors in MDCT and in particular to also highlight technical and procedural errors.

"HRCT predictors of GGO surgical resection: Histopathological and molecular correlation in the era of lung sparing surgery".

OBJECTIVES: Ground-glass pulmonary opacities (GGOs) are increasingly encountered in routine clinical practice and an accurate differentiation between benign and malignant lesions is crucial. The aim of this study is to evaluate the relationship between radiological features and the actual biological behavior of these nodules. The secondary endpoint is to identify any radiological predictors able to choose the type of surgical resection and the extent of lymphadenectomy. MATERIALS AND METHODS: This single-center retrospective study included all patients, who underwent high resolution computed tomography (HRCT) and surgical resection for GGOs between 2010 and 2020. Histopathological sampling focused on lesion size, histology, growth pattern, amount of lepidic component, percentage of ground-glass (GG), grade of tumor and proliferation index (Ki67). RESULTS: In 56 patients enrolled, 65 lesions (15 pure GG and 50 part-solid) were resected (44 lobectomies, 9 anatomical segmentectomies, 12 wedge resections). A direct significant correlation was found between: the GG at HRCT and the amount of lepidic component (p < 0.0001; R = 0.305), the tumor grading and the lepidic component at HRCT (p = 0.003), the percentage of GG and the expression of Ki67 (p = 0.016), the lepidic percentage and the expression of Ki67 (p = 0.004; R = 0.223). A total of 609 lymph-nodes were removed (stations N1 and N2) and histopathological analysis was negative for nodal involvement in all cases. CONCLUSION: Pure and part-solid GGOs could benefit from less invasive and lung sparing surgery with just nodal sampling. These would reduce surgical complications and guarantee a better quality of life for the patient. The major limitations are the number of patients and the lack of a longer follow-up.

Gastrointestinal stromal tumors (GIST): a proposal of a "CT-based predictive model of Miettinen index" in predicting the risk of malignancy.

PURPOSE: To identify the predictors of malignancy on CT for the evaluation of gastrointestinal stromal tumors (GIST) by correlating CT findings with the mitotic index in order to propose a "CT-based predictive model of Miettinen index." METHODS: One radiologist and one resident in radiology with 14- and 4-year experience in oncological field reviewed the CT findings of 42 patients by consensus, with respect to lesion site, size, contour, tumor growth pattern, enhancing pattern, degree of enhancement of tumor, percentage of tumor necrosis, mesenteric fat infiltration, ulceration, calcification, regional lymphadenopathy, direct invasion to adjacent organs, and distant metastasis. All parameters were correlated with the mitotic index evaluated at histopathological analysis following surgery. Normality of variables was evaluated using Shapiro-Wilk test. Pearson's correlation test was used to assess the interaction between variables. The diagnostic accuracy percentage of tumor necrosis was measured by receiver operating characteristic (ROC) analysis for detecting whether the number of mitosis per 50 high-power fields was > 5. RESULTS: A significant statistical correlation was found between percentage of tumor necrosis and the mitotic index (p < 0.005), dimension, and location of the tumor. CONCLUSION: CT could be an accurate technique in the prediction of malignancy of GIST in a CT risk assessment system, based on the location of the tumor, its size, and the percentage of tumor necrosis.

Structured reporting of chest CT in COVID-19 pneumonia: a consensus proposal.

OBJECTIVES: The need of a standardized reporting scheme and language, in imaging of COVID-19 pneumonia, has been welcomed by major scientific societies. The aim of the study was to build the reporting scheme of chest CT in COVID-19 pneumonia. METHODS: A team of experts, of the Italian Society of Medical and Interventional Radiology (SIRM), has been recruited to compose a consensus panel. They used a modified Delphi process to build a reporting scheme and expressed a level of agreement for each section of the report. To measure the internal consistency of the panelist ratings for each section of the report, a quality analysis based on the average inter-item correlation was performed with Cronbach's alpha (Cα) correlation coefficient. RESULTS: The overall mean score of the experts and the sum of score were 3.1 (std.dev. ± 0.11) and 122 in the second round, and improved to 3.75 (std.dev. ± 0.40) and 154 in the third round. The Cronbach's alpha (Cα) correlation coefficient was 0.741 (acceptable) in the second round and improved to 0.789 in the third round. The final report was built in the management of radiology report template (MRRT) and includes n = 4 items in the procedure information, n = 5 items in the clinical information, n = 16 in the findings, and n = 3 in the impression, with overall 28 items. CONCLUSIONS: The proposed structured report could be of help both for expert radiologists and for the less experienced who are faced with the management of these patients. The structured report is conceived as a guideline, to recommend the key items/findings of chest CT in COVID-19 pneumonia.

Small (< or = 2 cm) atypical hepatic haemangiomas in the non-cirrhotic patient: pattern-based classification scheme for enhancement at triple-phase helical CT.

PURPOSE: The aim of this study was to determine by triplephase helical computed tomography (CT) the appearance of atypical small (< or = 2 cm) hepatic haemangiomas (HHs) in the non-cirrhotic patient. MATERIALS AND METHODS: We retrospectively reviewed the hepatic arterial-dominant phase (HAP), portal venous phase (PVP) and delayed-phase (DP) helical CT images of 47 patients with 52 atypical small (< or = 2 cm) HHs associated with 34 typical small HHs. Images were assessed to identify the patterns of enhancement of atypical HHs and correlate their appearance with that of typical small HHs in the delayed phase. Interobserver variability and kappa value were calculated. Statistical significance was calculated by the Fisher exact test. RESULTS: The 52 atypical small HHs were categorised as follows: type 1a (hyperattenuating in the HAP, n=17), type 1b [hyperattenuating with transient hepatic attenuation difference (THAD) around the lesion in the HAP, n=12], type 2a (homogeneously hypoattenuating in the HAP or PVP, n=9), type 2b (hypoattenuating with "bright-dot" sign in the HAP or PVP, n=13) and type 3 (hypoattenuating with central enhancing area, n=1). Interobserver agreement was perfect for HHs of types 1a, 1b, 2a and 3. On DP images, the appearance of atypical small HHs was identical to that of typical small HHs in all cases (p<0.0001), with lesions showing homogeneous isoattenuation to the aorta or liver parenchyma without peripheral capsule. CONCLUSIONS: Triple-phase helical CT scans can distinguish several types of atypical small HHs. The demonstration of patterns similar to those of typical forms on DP CT is fundamental for the diagnosis.

Pleuroparenchymal fibroelastosis (PPFE) associated with giant cell arteritis: A coincidence or a novel phenotype?

Pleuroparenchymal fibroelastosis (PPFE) is a rare interstitial lung disease characterized by the fibrotic thickening of subpleural and parenchymal areas of the upper lobes. It may be both idiopathic or secondary to infections, interstitial lung diseases and/or drug exposure. Often PPFE patients report recurrent lower respiratory tract infections, suggesting that repeated inflammatory alterations induced by pulmonary infections may contribute to the development/progression of PPFE. Here, we report for the first time the case of a patient affected by Giant cell Arteritis with histologically proven PPFE. The lung involvement in GCA is rare and interstitial lung diseases are usually reported as an uncommon clinical manifestation of GCA. Our patient is probably the first case presenting PPFE associated with GCA and we wonder if this is a real associative disease or a coincidence perhaps, secondary to drug effects.

Magnetic resonance imaging in Tietze's syndrome.

OBJECTIVE: To evaluate the usefulness of magnetic resonance imaging (MRI) in Tietze's syndrome which, to our knowledge, has not previously been reported in the literature. METHODS: Twelve consecutive outpatients with clinical features of Tietze's syndrome underwent evaluation, including the anamnesis, clinical general examination, clinical evaluation of costosternal and sternoclavicular joints (SCJ) and biochemical and instrumental investigations. Twenty normal subjects age- and sex-matched to the patients' group were examined in a similar manner. MRI of costosternal and SCJ was performed using a 1.5 Tesla unit (Gyroscan NT 1.5 Philips, The Netherlands and GE Signa Excite HD, GE Healthcare, Milwaukee, Wis., USA). RESULTS: The MRI pattern of primary Tietze's syndrome was characterized as follows: enlargement and thickening of cartilage at the site of complaint (12/12 patients); focal or widespread increased signal intensities of affected cartilage on both TSE T2-weighted and STIR or FAT SAT images (10/12 patients); bone marrow oedema in the subcondral bone (5/12 patients); vivid gadolinium uptake in the areas of thickened cartilage, in the subcondral bone marrow and/or in capsule and ligaments (10/12, 4/12 and 7/12 patients respectively). CONCLUSION: Magnetic resonance is an excellent technique to evidence both the cartilage and bone abnormalities, therefore it represents the elective method in the investigation of primary Tietze's syndrome, due to its high sensitivity, diagnostic reliability and biological advantages thanks to the lack of ionizing radiation.

Primary hepatic epithelioid hemangioendothelioma progressively responsive to interferon-alpha: is there room for novel anti-angiogenetic treatments?

Primary hepatic epithelioid hemangioendothelioma (HEH) is a rare, low-grade malignant neoplasm of endothelial origin, with an unpredictable clinical course and prognosis. No standard therapeutic strategies are still available for HEH, due to the infrequency of the disease and to its variable natural history that limit the identification of the most effective treatment. In the absence of metastatic disease, surgical resection or liver transplantation represent the treatment of choice for HEH, while several antineoplastic agents have been proposed in the presence of metastatic nonresectable disesase. Herein, we describe the biological characterization and the clinical course of a primary HEH progressively responsive to treatment with intermediate doses of interferon-alpha (IFN)-alpha2a. Furthermore, based on the newly-identified expression of endoglin (CD105) on HEH, we discuss the clinical potential of novel anti-angiogenetic approaches to the disease.

Could MRI visualize the invisible? An Italian single center study comparing magnetic resonance lymphography (MRL), super microsurgery and histology in the identification of lymphatic vessels.

OBJECTIVE: Aim of this study is to evaluate the possibility of limb magnetic resonance lymphography (MRL) to differentiate lymphatic vessels from pathological veins, collect a specimen of the identified lymphatic vessel during operations of super microsurgical lymphatic-venular anastomosis (s-LVA) and perform immunohistochemical stainings to confirm the nature of the collected vessels. PATIENTS AND METHODS: Twenty patients presenting lymphedema were enrolled in this study. Five patients reported lower limb lymphedema and 15 patients reported upper limb lymphedema. All patients had the indication for s-LVA and underwent preoperative MRL imaging of the affected limb. A total of 57 lymphatic vessels were identified by MRL and used to guide s-LVA: all these vessels have also been used to perform an intraoperative biopsy for immunohistochemical evaluation. RESULTS: A total of 53/57 vascular structures resulted compatible with lymphatic vessels at the immunohistochemical study performed with D2-40 antibody; 3/57 specimen showed the absence of the D2-40 antibody. A significant association was found between preoperative MRL and immunohistochemical marker D2-40 on collected specimen. CONCLUSIONS: Most of the articles in the international literature report the concomitant presence of both lymphatic and venous vessels at MRL. However, no one in literature describes the possibility to differentiate venous vessels from lymphatic vessels, and this is a crucial issue for the correct evaluation of the lymphatic system in patients with limb lymphedema undergoing a future surgical correction. In the present study, MRL allowed to identify active lymphatic vessels. MRL was predictive to determine preoperatory lymphatic vessels and to perform successful s-LVA in lymphedema patients. This is the first study to prove the nature of the vessels identified at the preoperative MRL with immunohistochemical stainings.

Water/cortical bone decomposition: A new approach in dual energy CT imaging for bone marrow oedema detection. A feasibility study.

INTRODUCTION: Many studies aimed at validating the application of Dual Energy Computed Tomography (DECT) in clinical practice where conventional CT is not exhaustive. An example is given by bone marrow oedema detection, in which DECT based on water/calcium (W/Ca) decomposition was applied. In this paper a new DECT approach, based on water/cortical bone (W/CB) decomposition, was investigated. MATERIALS AND METHODS: Eight patients suffering from marrow oedema were scanned with MRI and DECT. Two-materials density decomposition was performed in ROIs corresponding to normal bone marrow and oedema. These regions were drawn on DECT images using MRI informations. Both W/Ca and W/CB were considered as material basis. Scatter plots of W/Ca and W/CB concentrations were made for each ROI in order to evaluate if oedema could be distinguished from normal bone marrow. Thresholds were defined on the scatter plots in order to produce DECT images where oedema regions were highlighted through color maps. The agreement between these images and MR was scored by two expert radiologists. RESULTS: For all the patients, the best scores were obtained using W/CB density decomposition. CONCLUSIONS: In all cases, DECT color map images based on W/CB decomposition showed better agreement with MR in bone marrow oedema identification with respect to W/Ca decomposition. This result encourages further studies in order to evaluate if DECT based on W/CB decomposition could be an alternative technique to MR, which would be important when short scanning duration is relevant, as in the case of aged or traumatic patients.

Two-year-results of Endurant stent-graft in challenging aortic neck morphologies versus standard anatomies.

AIM: The aim of this paper was to evaluate the influence of a challenging neck on mid-term results using the Endurant I stent-graft system in high risk patients. METHODS: A retrospective study was conducted on a prospectively compiled database of 72 elective patients with challenging neck treated with the Endurant I system (Endurant Stent Graft, Medtronic AVE, Santa Rosa, CA, USA). These patients were compared to a control group (65 patients) without significant neck problems. The endpoints were mid-term 2-years technical, clinical success and the event free survival of all treated patients. RESULTS: Mean age was 76.12 years; 76.6% of patients were males. Risk factors and preoperative variables did not differ significantly between the two groups. Only 4 (5.5%) patients of the study group vs. 2 (3.1%) in the control group developed type I endoleak during the follow-up. Three (4.1%) study group patients developed type III endoleak vs. 2 (3.1%) in the control group. All these patients required an adjunct procedure of relining with a new endograft. No type II endoleaks requiring adjunctive endovascular procedures were detected in our series. The 2-year event free survival rate did not differ statistically between the two groups (P=0.425). CONCLUSION: Treatment with the Endurant stent-graft is technically feasible and safe, yielding satisfactory results even in challenging anatomies. Mid-term results are promising and challenge current opinion concerning the negative influence of challenging neck anatomy on EVAR especially after a longer follow-up.

Cystic gastrointestinal stromal tumors of the pancreas simulating cystoadenocarcinoma. Report of three cases and short review of the literature.

Gastrointestinal stromal tumors (GISTs) represent a distinct subset of mesenchymal tumours of the gastrointestinal tract. They are more common in the stomach and small intestine, and are characterized by the proliferation of spindle or epithelioid cells and by the expression of CD117. Extra-gastrointestinal stromal tumors are rare and only 13 cases of pancreatic GISTs have been reported in the literature, only 1 of which presented as a cystic lesion. Mutational analysis of KIT and Platelet derived growth factor receptor-α genes was performed only in two out of the 13 cases. We report 3 cases of cystic GISTs of the pancreas, radiologically mimicking a cystoadenocarcinoma. Routine histopathology and molecular characterization of the tumours have been performed. In two of them, molecular analysis showed unusual genetic alterations (the internal repeat of codon 502 and 503 in exon 9 of the KIT gene and the KIT exon 9 single nucleotide substitution c.1427G⟩T). Pancreatic GIST should be included in the differential diagnosis of both cystic and solid masses of the pancreas. The diagnosis should be accomplished by a combination of radiology, histology, immunohistochemistry and molecular biology. The evaluation of CD117 expression and the sequence analysis of KIT and Platelet derived growth factor receptor-α gene is mandatory for therapy.

Utility of spiral CAT scan in the follow-up of patients with pulmonary Langerhans cell histiocytosis.

Pulmonary Langerhans cell histiocytosis (PLCH) is a rare disease that occurs almost exclusively in smokers, generally young adults between 20 and 40 years old. Prognostic biomarkers of the disease are lacking. This study describes the clinical-radiological features of a group of PLCH patients and applies a semi-quantitative CT score of the chest to verify the prognostic value of radiological findings in this disease. Clinical-radiological and immunological data from 12 Caucasian patients (6M, 7 smokers and 5 ex-smokers, mean age 36±8 years) were recorded at onset and after a follow-up period of 4 years. Application of the semi-quantitative CT score revealed a prevalently cystic pattern at onset and follow-up in the majority of the patients. Patients with a prevalently nodular pattern developed cystic lesions during follow-up. Interestingly, significant correlations were found between the extent of cystic lesions and DLCO values at onset (time 0: p<0.05) and at the end of follow-up (time 1, p<0.05) and with FEV1 values at time 0 (p<0.05) and time 1 (p<0.05). Patients with progressive functional decline were those with CT evidence of severe cystic alterations. The results suggest that high resolution CT scan of the chest is mandatory for characterizing PLCH patients at diagnosis and during follow-up. The proposed CT score of the chest showed potential prognostic value.

Diffusion-weighted magnetic resonance imaging in the evaluation of renal function: a preliminary study.

PURPOSE: Magnetic resonance diffusion-weighted imaging (MR-DWI) is useful to assess proton motion by the computation of an apparent diffusion coefficient (ADC). This property could be used to assess renal damage, with special regard to unilateral dysfunction. The aim of this study was to estimate the correlation between ADC and the stage of chronic renal failure (CRF) using a spin-echo echo-planar imaging (SE-EPI) sequence with the sensitivity encoding (SENSE) technique. MATERIALS AND METHODS: Fourteen patients (nine men and five women, mean age 49 years, range 22-66 years) underwent an MR examination on a 1.5-T system. Seven patients had a history of hypertension or CRF, one had Takayasu disease and one had nephrovascular hypertension. Five subjects without known kidney disease were used as controls. The glomerular filtration rate (GFR) assessed by Cockcroft-Gault's equation was used as a functional marker. The imaging protocol consisted of T1- and T2-weighted sequences followed by a SE-EPI acquisition with a diffusion gradient of 600 s/mm(2) and SENSE factor 2 and pixel-by-pixel ADC map reconstruction. In five patients, the SE-EPI-DWI sequence was repeated after i.v. administration of 1 mg of furosemide. RESULTS: ADC was of 2.44+/-0.24 x 10(-3) mm(2)/s in patients with normal GFR and of 2.05+/-0.33 x 10(-3) mm(2)/s (p<0.05) in subjects with altered GFR; a significant difference was found between stage III and IV (p<0.01), whereas no differences were found between stage I and II (p=0.27) and between stage II and III (p=0.39). A good correlation was found between GFR and ADC (r=0.79; p<0.01), with no significant change after furosemide administration (p=0.7). CONCLUSIONS: DWI is a feasible MR technique for assessing renal damage. Further studies with scintigraphic correlation are needed to confirm these results and to establish reference values for this imaging technique.