Additional Cross-sectional Imaging Research Articles

Ultrasound imaging of bowel obstruction in infants and children.

We review the etiologies of bowel obstruction in infants and children that can be identified on ultrasound (US) including perforated appendicitis, intussusception, foreign body ingestion, colonic volvulus, intra-abdominal mass lesions, internal hernia, and stricturing inflammatory bowel disease. US can potentially identify the cause of bowel obstruction in these age groups, without the need for additional cross-sectional imaging, and can aid in patient management including interventional and surgical planning. Hence, it is important to be familiar with the sonographic imaging findings of bowel obstruction in infants and children.

European Society of Pediatric Radiology survey of perioperative imaging in pediatric liver transplantation: (1) pre-transplant evaluation

BackgroundLiver transplantation is the state-of-the-art curative treatment in end-stage liver disease. Imaging is a key element for successful organ-transplantation to assist surgical planning. So far, only limited data regarding the best radiological approach to prepare children for liver transplantation is available.ObjectivesIn an attempt to harmonize imaging surrounding pediatric liver transplantation, the European Society of Pediatric Radiology (ESPR) Abdominal Taskforce initiated a survey addressing the current status of imaging including the pre-, intra-, and postoperative phase. This paper reports the responses on preoperative imaging.Material and methodsAn online survey, initiated in 2021, asked European centers performing pediatric liver transplantation 48 questions about their imaging approach. In total, 26 centers were contacted and 22 institutions from 11 countries returned the survey. From 2018 to 2020, the participating centers collectively conducted 1,524 transplantations, with a median of 20 transplantations per center per annum (range, 8–60).ResultsMost sites (64%) consider ultrasound their preferred modality to define anatomy and to plan surgery in children before liver transplantation, and additional cross-sectional imaging is only used to answer specific questions (computed tomography [CT], 90.9%; magnetic resonance imaging [MRI], 54.5%). One-third of centers (31.8%) rely primarily on CT for pre-transplant evaluation. Imaging protocols differed substantially regarding applied CT scan ranges, number of contrast phases (range 1–4 phases), and applied MRI techniques.ConclusionDiagnostic imaging is generally used in the work-up of children before liver transplantation. Substantial differences were noted regarding choice of modalities and protocols. We have identified starting points for future optimization and harmonization of the imaging approach to multicenter studies.

Nutcracker Syndrome: Challenges in Diagnosis and Surgical Treatment

Nutcracker syndrome (NCS) is an uncommon syndrome that presents with signs and symptoms caused by compression of the left renal vein (LRV), whereas 'nutcracker phenomenon' is solely used to refer to the anatomical configuration without clinical symptoms. Treatment for NCS may include nonoperative management, open surgical intervention, and in some instances endovascular stenting. We present a single-center retrospective case series of patients who presented with NCS managed with open surgical interventions. A single-center, retrospective review of patients managed from 2010-2021. We diagnosed NCS via a thorough clinical examination and additional cross-sectional imaging studies including magnetic resonance venography and/or computed tomography venography. For further confirmation of the diagnosis, duplex ultrasound was frequently combined with contrast venography. Thirty eight patients were included in our study from 2010-2021. Twenty one (55.3%) patients presented with symptoms including flank pain, abdominal pain, hematuria, and fatigue. The remaining 17 (44.7%) patients had nutcracker phenomenon. Within the group of patients diagnosed with NCS, 11 patients underwent LRV transposition. Symptoms related to NCS improved in 10 patients. Hematuria in 1 patient did not improve. Transposition of the LRV is an effective treatment for NCS. Nonoperative management is an option for those patients experiencing less severe or nonspecific clinical symptoms.

Use of CEUS for Imaging Evaluation of Pediatric Peritonsillar Abscess.

Peritonsillar abscess can be diagnosed by B-mode ultrasound and cross-sectional imaging. The latter (with MRI being the modality of first choice in children) is associated with higher effort and risk for pediatric patients due to the administration of X-rays and/or the need of sedation. The purpose of this study is to evaluate whether the introduction of CEUS into the diagnostic algorithm for suspected pediatric peritonsillar abscess is suitable and advantageous. Single-institution retrospective review of data of pediatric patients who were presented to the department of pediatric radiology for sonographic evaluation under the suspicion of peritonsillar abscess. Diagnostic performance of CEUS was evaluated by using surgical exploration or clinical follow-up as the reference standard. 284 children included in the study underwent B-mode ultrasound. Mean age of all patients was 6,23 years. Peritonsillar abscess was the diagnosis in 42 patients. Diagnosis of peritonsillar abscess was made by B-mode ultrasound alone in 13 of 42 patients (31 %). In 17 of 42 patients (40 %), diagnosis was made by a combination of B-mode ultrasound and CEUS. Sensitivity rose from 37 % to 86 % in cases where B-mode ultrasound remained unclear and CEUS was used. Contrast-enhanced ultrasound (CEUS) is suitable and efficient for the diagnosis of peritonsillar abscess in pediatric patients. It increases the sensitivity for the diagnosis of peritonsillar abscess and thereby reduces the need of additional cross-sectional imaging for the pediatric patients.

Point-of-care ultrasonography: Downstream utilization of and diagnostic (dis)agreements with additional cross-sectional imaging

ObjectivesPoint-of-care ultrasonography (POCUS), defined as ultrasonography (US) performed and interpreted by the clinician, is increasingly performed. This study aimed to determine the frequency of and reasons why clinicians of the emergency department request cross-sectional imaging after POCUS and how often radiologists experience diagnostic (dis)agreements. MethodsThis retrospective study included a consecutive series of 503 patients who underwent POCUS at the emergency department of a tertiary care center. ResultsDownstream cross-sectional imaging was performed in 77 (15.3%) of 503 POCUS examinations. Reasons for additional cross-sectional imaging were, in order of decreasing frequency: suspicion of pathology that was not assessed with POCUS in 46 cases (59.7%), confirmation of conclusive POCUS findings in 21 cases (27.3%), inconclusive POCUS (i.e. insufficient visualization of the structure of interest to make a diagnosis, despite an attempt of the POCUS operator) in 7 cases (9.6%), a combination of inconclusive POCUS and suspicion of pathology that was not assessed with POCUS in 2 cases (2.6%), and clarification of incidental findings on POCUS in 1 case (1.3%). In the 21 cases that underwent additional cross-sectional imaging to confirm POCUS findings, POCUS agreed with additional cross-sectional imaging in 19 (90.5%) and disagreed in 2 (9.5%) cases. ConclusionsThe use of POCUS appears to not cause any considerable downstream overutilization of cross-sectional imaging. In addition, radiologists experience few diagnostic disagreements when asked to perform second opinion cross-sectional imaging. Future studies with more homogeneous datasets in terms of POCUS operators are required to confirm our results.

Role of Dual-Energy Computed Tomography in Gallbladder Disease: A Review

AbstractGallbladder diseases are common and include a spectrum ranging from benign to cancer. Imaging plays an integral role in the diagnosis and in guiding appropriate management. While most patients with gallstone (GS) diseases can be evaluated with ultrasound, those with complicated GS disease, suspicion of cancer, or staging of cancer need additional cross-sectional imaging. Computed tomography (CT) is widely available and is often the imaging test of choice following an equivocal ultrasound or negative ultrasound in patients with unexplained symptoms. Conventional CT has limited sensitivity in detecting GS or common bile duct stones. In other scenarios, including diagnosis of acute cholecystitis (AC) and characterization of gallbladder wall thickening, an increase in accuracy using novel techniques is desirable. Dual-energy computed tomography (DECT) is increasingly incorporated into clinical practice. DECT has shown promising results in the detection of cholesterol stones that otherwise go unnoticed on conventional CT. However, its role beyond GS disease has largely been unexplored. In this review, we discuss the available literature on the DECT in biliary diseases and discuss the potential applications of this technique.

Sonography in Childhood and Adolescence for General Radiologists - More Possibilities Than Expected...

Sonography is the most common imaging modality in childhood and adolescence. The rapid availability, absence of X-rays, bedside applicability, e. g., in intensive care units, the lack of need for sedation, and last but not least the very good ultrasound conditions in the vast majority of cases are the main advantages of sonography. Due to the spectrum of patients, from premature infants to adolescents, a great variety of questions arise for the examiner. This requires knowledge of the various disease patterns in the different age groups. Proper handling of the young patients as well as their parents is essential in order to make the examination conditions as optimal as possible. Due to the smaller body size compared to adults, sonographic examinations of the abdomen and thorax in children and adolescents are usually possible with very good image quality. In the majority of cases, a definitive diagnosis is made by sonography without additional cross-sectional imaging, which is more common in adults. Due to the acoustic windows provided by the still open fontanelles, excellent image quality of the central nervous system is usually possible in the first year of life. In most cases, complex MRI examinations are not necessary. Due to the partly still missing ossification of the bony structures, further acoustic windows are available, which allow an examination of, e. g., the spinal canal. Ultrasound also plays a major role in the examination of soft tissues and the musculoskeletal system in childhood and adolescence, not only in hip ultrasound. The aim of this article is to show this very broad spectrum for colleagues working predominantly in adult radiology, to highlight some representative examples and to present the respective clinical features in childhood and adolescence. KEY POINTS:: · Ultrasound is the most important initial imaging modality in children and adolescents.. · Often, no further cross-sectional imaging is necessary.. · The most important area of application is the abdomen and pelvis.. · Furthermore, there are additional special applications such as CNS in neonates and infants, thorax, musculoskeletal system.. CITATION FORMAT: · Schaal MC, Moritz JD, Mentzel H et al. Sonography in Childhood and Adolescence for General Radiologists - More Possibilities Than Expected.... Fortschr Röntgenstr 2022; 194: 521 - 531.

Effects of Contrast-Enhanced Ultrasound of Indeterminate Renal Masses on Patient Clinical Management: Retrospective Analysis From 2 Institutions.

To investigate the long-term impact of contrast-enhanced ultrasound (CEUS) on the treatment of patients with indeterminate renal masses. In this retrospective study, consecutive charts of all patients receiving renal CEUS at 1 of 2 academic medical centers between January 1, 2014, and December 31, 2018, were reviewed. Patients were included in the study if they had documented chronic renal disease (estimated glomerular filtration rate < 60 mL/min/1.73 m2 ) or prior nephrectomy and received CEUS for a previously untreated renal mass. A total of 215 lesions in 157 patients were used for analysis. Contrast-enhanced ultrasound provided a final treatment recommendation in 71.6% of lesions (154 of 215). Of these 154 lesions, 7.8% (12 of 154) were lost to follow-up despite CEUS suggesting malignancy; 15.6% (24 of 154) went directly for surgical intervention, with malignancy confirmed by pathologic results in 87.5% (21 of 24) of these cases; and the remaining 76.6% (118 of 154) were deemed benign and required no additional follow-up. Of the 118 lesions diagnosed by CEUS as benign and requiring no follow-up, none showed evidence of later renal cell carcinoma development and, only 5.1% (6 of 118) of the total population was referred for further cross-sectional imaging of the mass in question. In 28.4% of all lesions (61 of 215), CEUS resulted in a recommendation for surveillance imaging at a 6- to 12-month interval, and less than 10% (6 of 61) of these underwent additional cross-sectional imaging within the recommended 6 months after CEUS. These findings highlight the impact of CEUS on clinical treatment of indeterminate renal masses, including reducing the use of the potentially nephrotoxic contrast agents and providing a direct pathway to transplant.

Harms of hepatocellular carcinoma surveillance.

Hepatocellular carcinoma (HCC) surveillance in patients with cirrhosis is associated with decreased mortality by enabling early tumor detection. However, the benefits of any cancer screening program must be considered in light of potential physical, financial, and psychological harms, as well as the risk of overdiagnosis. Herein, we summarize the potential harms of HCC surveillance. To date, two retrospective studies have addressed physical harms of HCC surveillance. Based on these data, 15% to 28% of patients undergoing HCC surveillance experience physical harm including additional cross-sectional imaging or liver biopsy. Although psychological and financial harms have been reported for other cancers, there are currently limited data specific to HCC. An ongoing multi-center prospective study assessing all four types of harms should provide data in near future. HCC screening may prevent death by diagnosing tumors at an early stage, but limited sensitivity and specificity of screening tests can result in unintended harms. There is a need for further quality data evaluating both the benefits and harms of HCC surveillance.

Contrast-enhanced ultrasound (CEUS) for the evaluation of gallbladder diseases in comparison to cross-sectional imaging modalities and histopathological results.

The first method of choice for gallbladder alteration detection is the conventional ultrasound. Due to some imaging limitations, contrast-enhanced ultrasound (CEUS) has been widely used in the last years. CEUS is an additional modality that is able to depict microvessels flow and elucidate suspicious findings. The aim of this retrospective mono-center analysis study is to evaluate the performance of CEUS in gallbladder diseases and compare it to cross-sectional imaging modalities and histopathological results as gold standard. The retrospective study analysed 37 patients with gallbladder diseases between 2009 and 2017. All patients underwent CEUS examinations and additional cross-sectional imaging was also performed: CT imaging on 24 (64.9%) patients, MRI imaging on 18 (48.6%) patients, CT and MRI imaging on (28.7%). CEUS images were performed and interpreted by a single physician. CEUS imaging results of the gallbladder showed a sensitivity and specificity of 100%, a positive predictive value (PPV) of 100% and a negative predictive value (NPV) of 100%. CT imaging of the gallbladder showed a sensitivity of 100%, specificity of 75%, PPV of 100%, and NPV of 95%. MR imaging of the gallbladder showed a sensitivity of 100%, specificity of 93%, PPV of 75%, and NPV of 100%. Ultrasound imaging plays an essential role in the evaluation of gallbladder disease. Due to additional features of contrast-enhanced ultrasound, it is possible to differentiate gallbladder pathologic alterations by depicting its micro and macrocirculation and display important malignant features that recommends prompt management. Patients with contraindications to other cross-sectional imaging modalities benefit from this safe technique.

Sichere Diagnostik zystischer Nierenläsionen

Cystic renal lesions are commonly seen during routine ultrasound examinations of the abdomen. Some cystic renal lesions cannot be sufficiently characterized using native ultrasound. In these cases additional imaging might be necessary. Contrast-enhanced ultrasound (CEUS) is areliable imaging modality to characterize cystic renal lesions. Contrast enhancement of septations and the cystic wall are visualized in high resolution. This information helps to categorize the cystic renal lesions applying the CEUS Bosniak classification. This classification helps to estimate the probability of amalignant etiology of cystic renal lesions. Using CEUS, cystic renal lesions can be characterized with ahigh sensitivity and specificity. The advantages of CEUS include that there is no effect on the function of the kidneys or the thyroid gland and no radiation exposure. In some cases, additional cross-sectional imaging is necessary to optimize diagnostic accuracy. CEUS is ahelpful imaging modality to characterize cystic renal lesions, to avoid unnecessary follow-ups and to detect malignant cystic renal lesions.

Diagnostic accuracy of imaging studies in congenital lung malformations

BackgroundAlthough fetal ultrasound, fetal MRI and postnatal CT are now widely used in the evaluation of congenital lung malformations (CLM), their diagnostic accuracy remains undefined.ObjectiveTo correlate prenatal and postnatal imaging...

External Validation of University of Wisconsin's Clinical Criteria for Obtaining Maxillofacial Computed Tomography in Trauma.

Patients sustaining multisystem trauma are at risk for oral and maxillofacial fractures. Although the University of Wisconsin established criteria to help guide the clinician in obtaining additional cross-sectional imaging to evaluate possible facial fractures, it has not been externally validated. Our aim was to evaluate whether the University of Wisconsin's Criteria is generalizable to external institutions through validation and to report modern practice patterns at a level 1 trauma center. A retrospective case study was performed of all patients who had computed tomography of the facial bones (CT face) at a tertiary, academic, Level 1 trauma center over the 6-month period ending on June 30, 2015. The electronic medical record was reviewed for the 5 University of Wisconsin criteria (bony step off or instability, periorbital ecchymosis, malocclusion, tooth absence, and glasgow coma scale). Final interpretation of CT face findings by board-certified radiologists (facial fractures, intracranial hemorrhage, and cervical spine injury) were also captured. Our modeling was similar to that described by the reference study, the internal validation study. Sensitivity, specificity, negative, and positive predictive values with 95% confidence intervals were evaluated. A P < 0.05 was considered significant. The presence of any ≥1 of the 5 criteria identified on physical examination resulted in 81% sensitivity for any facial fracture, which is lower than the sensitivity initially described (98%) and subsequently internally validated (97%). The absence of all 5 physical examination criteria had a negative predictive value of 60%, again lower than that initially described (87%) and then internally validated (81%). We were unable to validate the University of Wisconsin criteria for predicting facial fractures. These criteria may be institutionally specific and not generalizable to other trauma centers. Further research to refine the criteria for CT of the face is needed to improve resource allocation.

Imaging of Wrist Injuries: A Standardized US Examination in Daily Practice.

The keys to successful ultrasonography (US) of the wrist include knowledge of the relevant anatomy and understanding the biomechanical aspects. A wide spectrum of pathological findings including bone fractures (scaphoid, triquetrum) and ligament lesions (dorsal intercarpal and radiocarpal ligaments, scapholunate ligament) can be caused by an identical traumatic mechanism determined on the basis of the position of wrist at the time of injury.In the setting of wrist trauma, an early diagnosis can minimize the potential for inappropriate or delayed treatment. We describe a practical radiological approach by using a standardized imaging protocol: standard radiographs (four views) associated with an US examination focused on seven landmarks. If there is discordance between clinical and radiological features or if the diagnosis of a disruption of the scapholunate ligament remains uncertain, additional cross-sectional imaging (MRI or CT arthrogaphy) should be performed.

Sonography of pediatric superficial lumps and bumps: illustrative examples from head to toe.

Superficial lumps and bumps are extremely common in children, and the vast majority ultimately prove to be benign. Duplex/color Doppler ultrasound (US) has emerged as the first-line imaging modality for the evaluation of these superficial pediatric masses because it provides a means for rapid acquisition of information including size, shape, location, internal content and vascularity. More important, it does so without utilizing radiation, iodinated contrast material or sedation/anesthesia. In this review, we present the sonographic findings of a variety of cases ranging from head to toe that are either uncommonly seen or were diagnosed in an atypical fashion (i.e. ultrasound). In situations where the lesion is too deep, hyperechoic or large to be fully assessed within the field of view or if malignancy is suspected, then additional cross-sectional imaging is warranted for further evaluation.

Current use of PSMA-PET in prostate cancer management.

Currently, the findings of imaging procedures used for detection or staging of prostate cancer depend on morphology of lymph nodes or bone metabolism and do not always meet diagnostic needs. Prostate-specific membrane antigen (PSMA), a transmembrane protein that has considerable overexpression on most prostate cancer cells, has gained increasing interest as a target molecule for imaging. To date, several small compounds for labelling PSMA have been developed and are currently being investigated as imaging probes for PET with the (68)Ga-labelled PSMA inhibitor Glu-NH-CO-NH-Lys(Ahx)-HBED-CC being the most widely studied agent. (68)Ga-PSMA-PET imaging in combination with multiparametric MRI (mpMRI) might provide additional molecular information on cancer localization within the prostate. In patients with primary prostate cancer of intermediate-risk to high-risk, PSMA-based imaging has been reported to improve detection of metastatic disease compared with CT or mpMRI, rendering additional cross-sectional imaging or bone scintigraphy unnecessary. Furthermore, in patients with biochemically recurrent prostate cancer, use of (68)Ga-PSMA-PET imaging has been shown to increase detection of metastatic sites, even at low serum PSA values, compared with conventional imaging or PET examination with different tracers. Thus, although current knowledge is still limited and derived mostly from retrospective series, PSMA-based imaging holds great promise to improve prostate cancer management.

FDG-PET/CT pitfalls in oncological head and neck imaging.

ObjectivesPositron emission tomography-computed tomography (PET/CT) with fluorine-18-fluorodeoxy-D-glucose (FDG) has evolved from a research modality to an invaluable tool in head and neck cancer imaging. However, interpretation of FDG PET/CT studies may be difficult due to the inherently complex anatomical landmarks, certain physiological variants and unusual patterns of high FDG uptake in the head and neck. The purpose of this article is to provide a comprehensive approach to key imaging features and interpretation pitfalls of FDG-PET/CT of the head and neck and how to avoid them.MethodsWe review the pathophysiological mechanisms leading to potentially false-positive and false-negative assessments, and we discuss the complementary use of high-resolution contrast-enhanced head and neck PET/CT (HR HN PET/CT) and additional cross-sectional imaging techniques, including ultrasound (US) and magnetic resonance imaging (MRI).ResultsThe commonly encountered false-positive PET/CT interpretation pitfalls are due to high FDG uptake by physiological causes, benign thyroid nodules, unilateral cranial nerve palsy and increased FDG uptake due to inflammation, recent chemoradiotherapy and surgery. False-negative findings are caused by lesion vicinity to structures with high glucose metabolism, obscuration of FDG uptake by dental hardware, inadequate PET scanner resolution and inherent low FDG-avidity of some tumours.ConclusionsThe interpreting physician must be aware of these unusual patterns of FDG uptake, as well as limitations of PET/CT as a modality, in order to avoid overdiagnosis of benign conditions as malignancy, as well as missing out on actual pathology.Teaching points• Knowledge of key imaging features of physiological and non-physiological FDG uptake is essential for the interpretation of head and neck PET/CT studies.• Precise anatomical evaluation and correlation with contrast-enhanced CT, US or MRI avoid PET/CT misinterpretation.• Awareness of unusual FDG uptake patterns avoids overdiagnosis of benign conditions as malignancy.

Triplane fractures: do we need cross-sectional imaging?

Diagnosis of Triplane fractures remains difficult in common practice. Aim of the study was the evaluation of the fracture pattern and the benefit of cross-sectional imaging in classification of Triplane-fractures. A total of 27 pediatric patients treated for ankle fractures were identified from patient charts. Radiographic images of epiphyseal fractures (X-rays and additional cross-sectional imaging) were blinded evaluated by 13 observers to answer a specific questionnaire regarding type or fracture and treatment suggestion. There were seven Triplane-I and eight Triplane-II fractures. The other physeal ankle fracture group consisted of four patients with a Twoplane-fracture, five Salter-and-Harris (SH) II, one SH-III, and two SH-IV fracture. Accuracy of classification improved considerably depending on the experience of the observer in pediatric trauma care. Surgeons specialized in pediatric trauma care classified correctly with conventional X-rays in 48.1% of all cases presented versus 31.5% appropriate diagnosis by younger fellows. Accuracy in exact specification of Triplane-fractures was comparable lesser in younger fellows (31.1 vs. 22%). Cross-sectional imaging improved classification of all fractures in both groups (75.6% specialized vs. 47.3% non specialized). Whereas availability of cross-sectional imaging improved treatment recommendation in specialized surgeons this benefit was not detectable for the doctors without specialization. Evaluation of fracture pattern showed a relatively stereotypical fracture pattern in Triplane-II fractures, whereas Triplane-I fractures were more variable. The additional information of cross-sectional imaging seems helpful for any physician in finding the right classification of a pediatric ankle fracture. However, the additive information appears especially viable for experienced surgeons to suggest the appropriate treatment.

131I SPECT/CT: a one-station imaging modality in the management of differentiated thyroid cancer

In patients with differentiated thyroid carcinoma (DTC), single-photon emission computed tomography/computed tomography (SPECT/CT) applied to diagnostic or therapeutic radioiodine (131I) whole-body scintigraphy (WBS) may accurately localize and help to distinguish benign from malignant sites of 131I uptake, with the potential to alter the management plan. 131I SPECT/CT is increasingly being used to evaluate patients with DTC and shows promise for improving imaging specificity and reducing false-positive results. Pre-ablation scans with 131I SPECT/CT contribute to the staging of thyroid cancer and the identification of regional and distant metastases prior to radioiodine therapy. Post-therapy scans with 131I SPECT/CT improve detection and localization of 131I accumulation in lymph node metastases and distant metastases compared with planar WBS and reduce the number of equivocal diagnoses and the need for additional cross-sectional imaging.

Adjustment of the Surgical Plan in Repair of Congenital Heart Disease: The Power of Cross-sectional Imaging and Three-dimensional Visualization

The purpose of this article is to study the importance of cross-sectional imaging in preoperative evaluation and surgical planning. Echocardiography is the modality of choice to diagnose cardiac diseases. However, in some cases, the data obtained from echocardiogram are insufficient or the image quality is poor. In these cases, additional modalities are being used to provide further information that can aid in guiding medical management of or surgical planning for the patient. Cross-sectional imaging has become widely available in many institutions. These imaging techniques, especially with three-dimensional reconstructions, provide realistic images that have imperative diagnostic values. Moreover, the possibility of sophisticated image-processing techniques provides important hemodynamic characteristics via less invasive methods. In this article, we present three cases in which additional cross-sectional imaging seemed to be a crucial step prior to surgical planning.