Abbreviated MRI Protocol for the Assessment of Ablated Area in HCC Patients.

BACKGROUND: Liver Imaging Reporting and Data Systems (LI-RADS) Treatment Response Algorithm (TRA) was created to provide a standardized assessment of hepatocellular carcinoma (HCC) following loco regional therapy. The aim of this study was to compare sensitivity of standard MRI protocol versus abbreviated protocol (only T1-Weigthed fat suppressed (FS) sequences pre- and post-contrast phase) in the detection of ablated area according to LI-RADS Treatment Response (LR-TR) categories. METHODS: From January 2015 to June 2020, we selected 64 patients with HCC, who underwent Radiofrequency ablation (RFA) or Microwave ablation (MWA) treatment. According to inclusion criteria, 136 pathologically proven treated HCC (median 2, range 1-3 per patient; mean size 20.0 mm; range 15-30 mm) in 58 patients (26 women, 32 men; median age, 74 years; range, 62-83 years) comprised our study population. For each ablated area, abbreviated protocol, and standard Magnetic Resonance Imaging (MRI) studies were independently and blindly assessed in random order within and between three expert radiologists. Each radiologist assessed the ablated area by using the following categories: "LR-TR Non-viable" = 1; "LR-TR Equivocal" = 2 and "LR-TR Viable" = 0. RESULTS: According to the concordance between MRI and Contrast enhancement ultrasound (CEUS) among 136 treated HCCs, 115 lesions were assessed as non-viable or totally ablate and 21 as viable or partially ablate. The accuracy for standard MRI protocol and abbreviated MRI protocol for predicting pathologic tumor viability of a consensus reading was 98.6% (sensitivity = 100%; specificity = 98.3%; positive predictive value = 91.3% and negative predictive value = 100%). No differences were found in sensitivity or specificity between standard MRI LR-TR viable and abbreviated MRI LR-TR viable categories (p value > 0.05 at McNemar test). CONCLUSION: The abbreviated dynamic protocol showed similar diagnostic accuracy to conventional MRI study in the assessment of treated HCCs, with a reduction of the acquisition study time of 30% respect to conventional MRI.

Is whole body low dose CT still necessary in the era of 18F-FDG PET/CT for the assessment of bone disease in multiple myeloma patients?

OBJECTIVE: Whole body low dose computed tomography (WBLDCT) is the first-choice imaging modality to identify bone involvement in multiple myeloma (MM). Because the unenhanced LDCT co-registered to positron emission tomography (PET) (LDCT/PET) has similar technical characteristics to WBLDCT, we aimed to assess its reliability in the detection of bone disease, for employing fluorine-18-fluorodeoxyglucose (18F-FDG) PET/CT as unique multimodality imaging method in MM patients. SUBJECTS AND METHODS: Thirty three consecutive MM patients were prospectively enrolled and evaluated with WBLDCT to assess bone involvement. In addition, patients underwent 18F-FDG PET/CT using a disease-tailored optimized LDCT protocol. To compare both methods, skeletal anatomical regions were identified and a per-region and per-patient analysis were performed using Cohen's k test. Low dose computed tomography/PET sensitivity, specificity and accuracy were also calculated. RESULTS: The two imaging modalities resulted highly concordant considering both patient-based (k=0.841) and region-based analysis; some discrepancies were observed in dorsal spine (k=0.809) and thorax (k=0.756). Low dose computed tomography/PET sensitivity, specificity and accuracy were 89.4%, 98.3% and 93.5%, respectively. CONCLUSION: Low dose computed tomography co-registered PET has comparable performance to WBLDCT. If confirmed on a lager sample, these encouraging results suggest the possibility to use this multimodal hybrid imaging as the only method for MM evaluation, rather than both exams, providing both morphologic and metabolic information in one session with impact on patient compliance, health care spending and especially radiation exposure.

Assessment of Ablation Therapy in Pancreatic Cancer: The Radiologist's Challenge.

This article provides an overview of imaging assessment of ablated pancreatic cancer. Only studies reporting radiological assessment on pancreatic ablated cancer were retained. We found 16 clinical studies that satisfied the inclusion criteria. Radiofrequency ablation and irreversible electroporation have become established treatment modalities because of their efficacy, low complication rates, and availability. Microwave Ablation (MWA) has several advantages over radiofrequency ablation (RFA), which may make it more attractive to treat pancreatic cancer. Electrochemotherapy (ECT) is a very interesting emerging technique, characterized by low complication rate and safety profile. According to the literature, the assessment of the effectiveness of ablative therapies is difficult by means of the Response Evaluation Criteria in Solid Tumors (RECIST) criteria that are not suitable to evaluate the treatment response considering that are related to technique used, the timing of reassessment, and the imaging procedure being used to evaluate the efficacy. RFA causes various appearances on imaging in the ablated zone, correlating to the different effects, such as interstitial edema, hemorrhage, carbonization, necrosis, and fibrosis. Irreversible electroporation (IRE) causes the creation of pores within the cell membrane causing cell death. Experimental studies showed that Diffusion Weigthed Imaging (DWI) extracted parameters could be used to detect therapy effects. No data about functional assessment post MWA is available in literature. Morphologic data extracted by Computed Tomography (CT) or Magnetic Resonance Imaging (MRI) do not allow to differentiate partial, complete, or incomplete response after ECT conversely to functional parameters, obtained with Position Emission Tomography (PET), MRI, and CT.

Usefulness of triphasic CT aortic angiography in acute and surveillance: Our experience in the assessment of acute aortic dissection and endoleak.

INTRODUCTION: Computed tomography angiography (CTA) has been widely used in the diagnostic evaluation of many aortic diseases, but no standardized techniques actually exist for aortic CTA. The aim of this study was to describe the usefulness of triphasic CTA in aortic assessment in both non-traumatic emergency and surveillance conditions. METHODS: We performed non ECG-gated CTA examinations with a 64-slice CT scanner using a triphasic protocol consisting of an unenhanced acquisition, and two (early and delayed) contrastographic phases with a delay of 25-30 s and 100-120 s respectively after the injection of contrast medium. Were retrospectively selected adult patients with imaging findings of acute aortic dissection (AAD) or endoleak (EL) from November 2012 to November 2014. RESULTS: AAD was detected in 36 (67%) patients: 23 type A-AADs, and 13 type B-AADs. The presence of EL was observed in 18 (33%) patients: 1 type Ia, 5 types IIa, 2 types IIb, 1 type IIIa and 9 types IIIb. DISCUSSION: Triphasic CTA is useful to provide correct and prompt diagnosis of AAD in emergency, allowing the evaluation of type and atypical forms of AAD, and the identification of possible branch-vessel involvement and complications. During surveillance, triphasic CTA assures accurate and complete assessment of all known and unknown ELs and it is essential for first follow-up examination. CONCLUSION: Triphasic CTA represents a reliable imaging tool for aortic assessment in both non-traumatic emergency and surveillance after endovascular aneurysm repair. Modified protocol could be employed in selected patients and tailored in their known disease.

Role of WB-MR/DWIBS compared to (18)F-FDG PET/CT in the therapy response assessment of lymphoma.

INTRODUCTION: This study prospectively evaluated whole-body magnetic resonance/diffusion-weighted imaging with body signal suppression (WB-MR/DWIBS) reliability compared to (18)F-FDG PET/CT in the treatment response assessment of classic Hodgkin lymphomas (HL) and aggressive non-Hodgkin lymphomas (aNHL). MATERIALS AND METHODS: Twenty-seven consecutive patients were prospectively enrolled at the time of diagnosis. Eighteen (11 HL and seven aNHL) were considered for the analysis. They received chemo/radiotherapy as induction and completed post-treatment evaluation performing both (18)F-FDG PET/CT and WB-MR/DWIBS. The revised response criteria for malignant lymphomas were used to assess the response to treatment. We evaluated the agreement between the two methods by Cohen's K test. Post-therapy WB-MR/DWIBS sensitivity, specificity, PPV, NPV and accuracy were then calculated, considering the 12 months of follow-up period as the gold standard. RESULTS: By using an evaluation on a lesion-by-lesion basis, WB-MR/DWIBS and (18)F-FDG PET/CT showed an overall good agreement (K = 0.796, 95% IC = 0.651-0.941), especially in the evaluation of the nodal basins in aNHL (K = 0.937, 95% IC = 0.814-1). In reference to the revised response criteria for malignant lymphomas, the two methods showed a good agreement (K = 0.824, 95% IC = 0.493-1). Post-therapy sensitivity, specificity, PPV, NPV and accuracy of WB-MR/DWIBS were 43, 91, 75, 71 and 72%, respectively. CONCLUSION: WB-MR/DWIBS seems to be an appropriate method for the post-treatment assessment of patients affected by HL and aNHL. The small discrepancies between the two methods found within HL could be due to the biological and metabolic behavior of this group of diseases. Larger prospective studies are necessary to better define the role of WB-MR/DWIBS in this setting of patients.

Role of plain radiography in the assessment of ingested foreign bodies in the pediatric patients.

Ingestion of various types of foreign bodies (FBs) such as coins, toy parts, jewelry pieces, needles and pins, fish and chicken bones, and button-type batteries is common among children. The curiosity of children and their need to investigate the world around them place them at a higher risk for ingestion of FBs. Fortunately, 80%-90% of ingested foreign objects that reach the stomach will pass uneventfully without intervention. The remainder may become blocked in the esophagus or other region of the alimentary tract, placing the pediatric patient at risk of significant complications such as aspiration, obstruction, bleeding, perforation, fistulization, sepsis, and death. The goals of the initial pediatric patient assessment are to identify the type of object ingested, its location in the gastrointestinal tract, and the presence of associated complications. Factors reported to increase the risk of complications included a sharp FB, a FB with a wide diameter, and symptoms. Plain radiographs still play an important role in the assessment of ingested FBs in the pediatric patient: plain films of the neck, chest, and abdomen are very useful in confirming the diagnosis of FB ingestion because most ingested FBs are radiopaque.

Imaging assessment of gunshot wounds.

Gunshot injuries occur when someone is shot by a bullet or other sort of projectile from a firearm. Wounds are generally classified as low velocity (less than 609.6m/s) or high velocity (more than 609.6m/s). Those with higher velocity may be expected, on this basis, to dissipate more energy into surrounding tissue as they are slow and cause more tissue damage, but this is only a very approximate guide. However, these terms can be misleading; more important than velocity is the efficiency of energy transfer, which is dependent on the physical characteristics of the projectile, as well as the kinetic energy, stability, entrance profile and path traveled through the body, and the biological characteristics of the tissues injured. Hemodynamically stable patients and patients who stabilized after simple immediate resuscitation were evaluated with a careful history and physical examination. A routine x-ray is performed in patients with gunshot wounds. Indication for total body computed tomography (CT) is based on the presence of signs and symptoms of vascular damage at clinical examination. Patients are immediately transferred in the operating room for surgery if more serious injuries that require immediate surgical care are not diagnosed, or hemostasis may be preliminary reached in the emergency room. Hemodynamically stable patients with no history and clinical examination showing suspected vascular damage are allowed in the radiology department for obtaining a total body CT scan with intravenous contrast medium and then transferred to the surgical ward trauma for observation. After 24 hours without the complications, patient can be discharged. CT is the procedure of choice to identify hemorrhage, air, bullet, bone fragments, hemothorax, nerve lesion, musculoskeletal lesions, and vessels injuries and is useful for assessing medicolegal aspects as trajectory and the anatomical structures at risk.

Imaging assessment and clinical significance of pneumatosis in adult patients.

Gas detection in the bowel wall and in portomesenteric venous vessels in adults has long been related to intestinal infarction and poor outcome; many case reports have shown that pneumatosis may be associated with a large variety of pathological situations, ranging from absolutely benign and asymptomatic forms to abdominal catastrophes. Several studies have been conducted on this topic with different conclusions, probably due to differences in population so that the clinical value of these signs is still questioned. Intestinal pneumatosis, especially if presenting with a band-like pattern and if associated with portomesenteric vein gas, when observed in an acute abdominal setting should raise the suspicion of mesenteric infarct and prompt a careful search for other signs of intestinal involvement, so as not to miss cases of life-threatening intestinal infarct or allow them to further evolve into extensive necrosis with worse prognosis. In this review we illustrate the most relevant aspects of these debated but significant radiological signs.

The role of computed tomography in the preoperative assessment of gastrointestinal causes of acute abdomen in elderly patients.

Gastro-intestinal disorders in older patients is a medical emergency that requires immediate medical care. Chances of recovery improve with an early diagnosis and treatment. It might be caused by a number of different diseases, including perforations by foreign bodies, colon cancer, diverticulitis, ischemia. CT is often the initial modality used to assess patients with acute abdomen, the radiologist may be the first to suggest such a diagnosis. Computed tomography allows to identify the site of gastrointestinal perforations, of ischemia and to determine the most predictive signs in this diagnosis. The purpose of this study was to assess the diagnostic performance of CT gastrointestinal emergency of elderly patients with nontraumatic acute abdominal pain. The cases of 126 consecutively registered patients 65 years old or older presenting to the emergency department with acute abdominal pain and who underwent CT were retrospectively reviewed by two radiologists. Diagnostic accuracy was calculated according to the level of correctly classified cases in both the entire cohort and a surgical subgroup and was compared between readings. Agreement between each reading and the reference diagnosis and interobserver agreement were assessed with kappa statistics. In both the entire cohort (87.5% vs 85.3%, p = 0.07) and the surgical group (94% vs 91%, p = 0.15), there was no significant difference in CT accuracy between diagnoses made by the radiologist. Agreement between the CT diagnosis and the final diagnosis was excellent. In the care of elderly patients, CT is accurate for diagnosing the cause of acute abdominal pain, particularly when it is of gastrointestinal surgical origin. Thus CT interpretation should not be delayed until complete clinicobiologic data are available, and the images should be quickly transmitted to the emergency physician so that appropriate therapy can be begun.

Role of computed tomography in the assessment of intraorbital foreign bodies.

Intraorbital foreign bodies (IOFBs) are a common occurrence worldwide and happen at a frequency of once in every 6 cases of orbital trauma. An orbital foreign body may produce a variety of signs and symptoms related to its size, composition, and ballistics. Retained foreign bodies may give rise to cellulitis, abscess, fistulas, and impaired vision and motility. Prompt detection and accurate localization of IOFBs are essential for the optimum management of patients, to enable the surgeon to plan the most atraumatic method of removing the IOFB. Computed tomography (CT) is very useful in determining the size of foreign bodies and localizing them as intraocular, extraocular, or retro-ocular. CT is generally considered the gold standard in the evaluation of IOFBs because it is safe to use with metallic IOFBs, excludes orbitocranial extension, and is also able to diagnose orbital wall fractures and orbital sepsis with high accuracy. Other potential complications excludible by CT are abscess formation in the orbit, bone, and brain. Magnetic resonance imaging is generally not recommended for the evaluation of the foreign bodies because of risks associated with magnetic metal.

The radiological assessment of axial involvement in psoriatic arthritis.

This article summarizes the state of radiological assessment of axial involvement in psoriatic arthritis (PsA). The definition and measurement of axial disease in PsA remain problematic and this situation in turn could affect the choice of approach to evaluate radiological findings of the spine. At present, the radiological assessment has been evaluated by using scoring systems borrowed from ankylosing spondylitis (AS). In particular, the Bath AS Radiology Index (BASRI) and the modified Stoke AS Spine Score (m-SASSS) have been validated for axial PsA. A recent study showed that BASRI and m-SASSS were valid instruments; however, neither score encompassed all radiological features of PsA. Therefore, a new index for assessing radiological axial involvement in PsA was developed--the PsA Spondylitis Radiology Index (PASRI). This new index encompassed a greater range of the spinal radiological features of PsA, providing a greater score range, and it correlated well with anthropometric and patient-reported outcomes. Recently, a study assessed the sensitivity to change of BASRI, m-SASSS, and PASRI, and showed that these 3 instruments provided a moderate sensitivity to change but high specificity to detect the true changes.