Cross-sectional Imaging Research Articles

CT-defined muscle density as a prognostic factor in multiple myeloma undergoing autologous stem cell therapy: a retrospective single center study.

Skeletal muscle quality assessment can be performed by cross-sectional imaging. Skeletal muscle density (SMD) identified to be of prognostic relevance of several clinically outcomes in patients with hematological diseases. The purpose of the present study was to establish the effect of SMD on overall survival (OS) and progression-free survival (PFS) in patients with multiple myeloma (MM). All patients with MM were retrospectively analyzed between 2009 and 2019. 127 patients were included into the analysis. Whole-body computed tomography (CT) was used to calculate skeletal muscle index (SMI), SMD, albumin-gauge score and intramuscular adipose tissue content (IMAC). Overall, 28 patients (22.0%) of the patient sample died. In the discrimination analysis muscle density was higher in non-survivors compared to survivors (mean 30.8 ± 12.5 versus 24.1 ± 15.8, p = 0.03) and IMAC was lower in non-survivors (-0.66 ± 1.8 versus -0.25 ± 0.21, p = 0.01). These differences, however, were not demonstrated in the logistic regression analysis, which could not show prognostic relevance for the investigated muscle density parameters on PFS or OS. CT-defined muscle density parameters have no prognostic relevance on survival in patients with MM undergoing autologous stem cell therapy, which was demonstrated in a comprehensive analysis. These results corroborate previous smaller studies that body composition might have a limited role in this tumor entity.

Enhancing pancreatic tumor delineation using dual-energy CT-derived extracellular volume fraction map.

Precise identification of pancreatic tumors is challenging for radiotherapy planning due to the anatomical variability of the tumor and poor visualization of the tumor on 3D cross-sectional imaging. Low extracellular volume fraction (ECVf) correlates with poor vasculature uptake and possible necrosis or hypoxia in pancreatic tumors. This work investigates the feasibility of delineating pancreatic tumors using ECVf spatial distribution maps derived from contrast enhanced dual-energy CT (DECT). Data acquired from radiotherapy simulation of 12 pancreatic cancer patients, using a dual source DECT scanner, were analyzed. For each patient, an ECVf distribution of the pancreas was computed from the simultaneously acquired low and high energy DECT series during the late arterial contrast phase combined with the patient's hematocrit level. Volume of interest (VECVf) maps in ECVf distribution of pancreas were identified by applying an appropriate threshold condition and a connected components clustering algorithm. The obtained VECVf was compared with the clinical gross tumor volume (GTV) using the positive predictive value (PPV), Dice similarity coefficient (DSC), mean distance to agreement (MDA) and true positive rate (TPR). As a proof of concept, our hypothetical threshold condition based on the first quartile separation of the ECVf distribution to find VECVf of the pancreas elucidates the tumor volume within the pancreas. Notably, 7 out of 12 cases studied for VECVf matched well with the GTV and the mean PPV of 0.83±0.12. The mean MDA (2.83±1.0) of the cases confirms that VECVf lies within the tolerance for comparing to the pancreatic GTV. For the remaining 5 cases, the VECVf is substantially affected by other compounding factors, e.g., large cysts, dilate ducts, and thus did not align with the GTVs. This work demonstrated the promising application of the ECVf map, derived from contrast enhanced DECT, to help delineate tumor target for RT planning of pancreatic cancer.

A Low-Cost Workflow to Generate Virtual and Physical Three-Dimensional Models of Cardiac Structures.

Three-dimensional modeling and printing (3DMP) of anatomical structures from cross-sectional imaging data can enhance the understanding of spatial relationships in complex congenital heart defects. Partially due to the substantial financial, material and personnel resources required, 3DMP is not yet universally used. Here, we describe a workflow that addresses and eliminates these drawbacks. The workflow utilizes the open-source software "3D Slicer" (The Slicer Community) and "Blender" (Blender Foundation) for segmentation and post-editing of datasets. This approach enables the generation of virtual or physical 3D models. The physical models are printed using a standard fused deposition modeling printer. The financial challenges that likely constrain the wider use of 3DMP are largely addressed by this approach. However, the workflow still requires a considerable amount of time to manually segment the imaging data. Three-dimensional modeling and printing might improve planning and safety of congenital cardiac surgical treatment. Furthermore, it is a useful tool for education of parents and medical professionals. This workflow increases its suitability for routine use also in regions with low economic resources.

OGC SO22 - Accuracy of CT and FDG/PET clinical staging within a dedicated multidisciplinary service for patients with oesophago-gastric cancer

Abstract Background Accurate staging for oesophago-gastric cancer is important in ensuring correct treatment pathways, avoiding unnecessary surgery and providing prognostication for patients. Previously, cross sectional imaging in accurately providing tumour (T) and nodal (N) staging has been variable for upper GI malignancies, with usage of invasive investigations such as EUS to provide more specific local staging. With the increased utilisation of specialist multidisciplinary involvement and improved technology, we aimed to assess whether CT and PET imaging may be able to provide sufficiently accurate staging required for treatment decision making. Method All patients who underwent oesoophagogastric resections between January 2022 and March 2024 were identified from our surgical database. Patients were included if they had oesophago-gastric cancer, and underwent curative resection without neo-adjuvant treatment. Data collected included age, gender, location of primary tumour, CT/PET staging, and final histology. Outcomes assessed included rate of understaging in clinical and pathological T and N staging, and sensitivity and specificity of imaging in identifying presence of nodal disease. Results 38 patients were included in this analysis. For oesophageal and GOJ cancers, T stage under-reporting occurred in 6/27 (22%) patients, and N under-reporting in 7/27 (27%) patients. Radiological staging correlated with final pathological staging in 55% of T staging and 59% of N staging. Sensitivity (55.56%, 95% CI 21-86%) and specificity (72.2%, 95% CI 46.5-90.3%) for nodal disease on CT/PET was low, however no tumour or nodal under-staging would have impacted management. Gastric cancer staging accuracy assessment was limited by small numbers (n=12), however T under-staging occurred in 5/12 (42%) patients and N under-staging occurred in 5/11 patients (45%). Conclusion Involvement of dedicated radiology services in multidisciplinary care for oesophago-gastric cancer provides adequate radiological staging to guide treatment. Gastric cancer clinical staging requires laparoscopic and endoscopic assessment for accurate tumour assessment and management guidance. Radiological under-staging is less common in oesophageal and GOJ tumours than gastric cancer and has minimal impact on patient management.

Benign, but Ominous, Pseudotumor in the Post-Sleeve Gastrectomy Hiatal Hernia: A Case Series

Abstract We have incidentally observed a finding not yet described in the literature, on both cross-sectional imaging and fluoroscopy, to correlate with increased obstructive symptoms in our post sleeve gastrectomy patients. This case series aims to show postsurgical imaging cases with the common underlying finding of a pseudotumor associated with hiatal herniae and obstructive symptoms. Because this clinical presentation may, in some cases, warrant postsurgical revision, knowledge of the imaging findings and their potential clinical significance is useful to radiologists who interpret routine cross-sectional imaging examinations as well as fluoroscopic evaluations of these post sleeve gastrectomy patients.

On the Effect of Randomly Oriented Grain Growth on the Structure of Aluminum Thin Films Deposited via Magnetron Sputtering

The microstructure of aluminum thin films, including the grain morphology and surface roughness, are key parameters for improving the thermal or electrical properties and optical reflectance of films. The first step in optimizing these parameters is a thorough understanding of the grain growth mechanisms and film structure. To investigate these issues, thin aluminum films with thicknesses ranging from 25 to 280 nm were coated on SiOx/Si substrates at ambient temperature under high-vacuum conditions and a low argon pressure of 3 × 10−3 mbar (0.3 Pa) using the radio frequency magnetron sputtering method. Quantitative analyses of the surface roughness and nanograin characteristics were conducted using atomic force microscopy (AFM), transmission electron microscopy (TEM), and X-ray diffraction. Changes in specular reflectance were measured using ultraviolet–visible and near-infrared spectroscopy. The low roughness values obtained from the AFM images resulted in high film reflectivity, even for thicker films. TEM and AFM results indicate monomodal, randomly oriented grain growth without a distinct columnar or spherical morphology. Using TEM cross-sectional images and the dependence of the grain size on the film thickness, we propose a grain growth mechanism based on the diffusion mobility of aluminum atoms through grain boundaries.

BN SO62 - Laparoscopic technique for right sided paraduodenal hernia repair: A clinical study and surgical insights

Abstract Background Paraduodenal hernias can present significant diagnostic and therapeutic challenges, with up to 50% potentially leading to bowel obstruction. A minimally invasive approach to repairing these defects offers reduced morbidity and quicker recovery. This report highlights the feasibility and safety of laparoscopic repair of a right-sided paraduodenal hernia. Method A 19-year-old female presented with persistent postprandial bilious vomiting and a long history of forceful regurgitation 10-30 minutes after eating. The preoperative evaluation, surgical technique and operative outcomes are detailed. Results Preoperative evaluation included magnetic resonance imaging, computed tomography and a barium swallow, revealing an incidental finding of the duodenojejunal flexure and most jejunal loops on the right side of the abdomen. A right paraduodenal hernia was diagnosed during laparoscopy. After delineating and reducing the hernia laparoscopically, the sac was obliterated by opening up the posterior aspect over the inferior vena cava. The repair was completed by suturing the hernia orifice and plicating the duodenum. The patient's symptoms resolved postoperatively, with no intraoperative or immediate postoperative adverse outcomes reported. Scheduled outpatient follow-up showed satisfactory resolution of symptoms. Conclusion The laparoscopic repair of the right paraduodenal hernia was successfully performed, leading to the resolution of the patient's symptoms. This case underscores the importance of considering laparoscopic approaches for managing complex and rare hernias, especially when cross-sectional imaging modalities do not clearly identify the cause of symptoms. The laparoscopic technique offers significant advantages, including reduced pain and faster recovery.

Abstract 4136597: Atherosclerotic plaque healing as a marker of plaque vulnerability: Insight from intracoronary polarization-sensitive optical frequency domain imaging

Background: Collagen is the major extracellular matrix that imparts mechanical strength to fibrous caps covering fibroatheromas. Intracoronary polarimetry with polarization-sensitive (PS) optical frequency domain imaging (OFDI) measures polarization properties, such as birefringence and depolarization (Figure 1). Birefringence is elevated in collagen and collagen-synthesizing smooth muscle cells, while depolarization is increased by the presence of macrophages and lipid/necrotic cores. Purpose: This study aimed to investigate polarimetric signatures of coronary lesions with healed coronary plaques (HCP) in patients with ACS and chronic coronary syndrome (CCS). Furthermore, we aimed to investigate diagnostic value for birefringence and depolarization of ACS culprit lesions discriminating from CCS target lesions. Methods: We conducted a single center prospective registry of intracoronary PS-OFDI imaging in patients with coronary artery disease (n = 50). A total of 862 OFDI frames selected from culprit or target lesions were analyzed. Coronary plaque phenotypes were assessed using conventional OFDI imaging. HCP was defined as plaques with one or more layers of different optical density and a clear demarcation from underlying components on intensity images. Birefringence and depolarization of the newer intima was measured in cross-sectional images. Birefringence and depolarization of ACS- and CCS-lesions were compared using a generalized estimating equation model. Receiver operating characteristic (ROC) analysis was used to investigate the diagnostic performance of polarimetric signatures for identifying ACS-lesions. Results: Compared to CCS-lesions, ACS-lesions featured significantly higher lipid-burden index and maximum lipid arc (both p < 0.05). Compared to the CCS-lesions, ACS-lesions exhibited significantly lower birefringence (p < 0.05) and higher depolarization (p < 0.05). In the ROC analysis for differentiating ACS-lesions from CCS-lesions, area under the curves (AUC) for birefringence and depolarization were 0.712 and 0.672, respectively. In the multivariable ROC analysis in diagnosing ACS lesions, combination of birefringence with depolarization improved the AUC to 0.755 (p ＝ 0.025). Conclusions: Intracoronary polarimetry provides quantitative assessment of plaque composition in patients. Further research is warranted to investigate whether birefringence can serve as a marker of healing failure following plaque rupture and erosion.

Abstract 4139162: Optical coherence tomography measures mechanical contractile properties of the beating murine heart

Introduction: Optical imaging techniques can characterize properties of tissue at high temporal and spatial resolution, offering unique insights into electrically excitable tissues such as nerve and muscle. We hypothesized that the gated high-speed optical coherence tomography (OCT) could profile the contractile properties of mouse myocardial tissue and facilitate investigations of microscale mechanical function in the beating heart. Methods: C57BL/6 male mice (n=6) underwent a sternotomy while anesthetized and ventilated and were imaged at baseline with OCT. Another cohort of C57BL/6 male mice (n=6) were sacrificed and the hearts were ex vivo perfused with crystalloid using a Langendorff system. These hearts were imaged at baseline and after inhibition of contractile function with blebbistatin. OCT was performed using a custom tissue stabilizer and a Thorlabs TEL 321 OCT system, which was synchronized to physiologic signals using custom hardware and software and cardiac pacing protocols (Fig. 1A and 1B). OCT cross-sectional B-scan images (Fig. 1C) were obtained throughout multiple cardiac cycles in both in vivo and ex vivo preparations. Data were processed in MATLAB and ImageJ using the workflow in Fig. 1D. Results: Highly reproducible cross-sectional mean intensity changes were observed over the contractile cycle in vivo and ex vivo (Fig. 1E, left and middle). With mechanical contraction inhibited by blebbistatin, this cyclical intensity extinguished, linking the optical scattering change measured by OCT to myocardial contraction (Fig. 1E, right). B-scan curves averaged over multiple mice and temporally aligned with the ECG waveform (Fig. 1F) demonstrate a signal intensity waveform that reproducibly varies with the contractile cycle for both in vivo and ex vivo preparations. In vivo and ex vivo baseline waveforms both had peak intensity during systole and minimum in end-diastole (Fig. 1F). Reproducibility in ex vivo beating heart preparations without blood perfusion provides evidence that myocardial mechanical properties, not red blood cell flow, generate the intensity changes. Conclusion: Gated high-speed OCT imaging can quantify the mechanical contraction wave in the myocardium. Combined with gated OCT angiography, OCT techniques will provide high resolution imaging of both blood flow and mechanical contractility of the beating heart in small animal models of heart disease.

Gold standard nephroureterectomy, chemoprophylaxis and surveillance in upper tract urothelial carcinoma.

The purpose of this review is to summarize the most recent evidence on surgical management, strategies to reduce tumor recurrence, and surveillance regimens in patients diagnosed with upper tract urothelial carcinoma (UTUC) and elected for radical treatment. Minimally invasive surgery is gaining momentum in the surgical management of UTUC. Chemoprophylaxis is still the gold standard to reduce intravesical recurrence after radical nephroureterectomy (RNU). Novel surveillance strategies have been proposed to adapt follow-up regimens to patients' characteristics. Minimally invasive surgery has been associated with comparable oncological outcomes to the open approach while improving postoperative morbidity. In these cases, bladder cuff excision (BCE) is mostly performed by an extravesical approach, that demonstrates a noninferiority compared to the intravesical one in terms of oncological outcomes. Although lymphadenectomy is recommended in patients with high-risk tumors, its benefits are still unclear. Currently, there is a lack of recent prospective trials on chemoprophylaxis to reduce intravesical recurrence post RNU, making single-dose postoperative chemotherapy instillation the standard treatment. Although novel risk stratification models were released by international urological guidelines, their validity is mainly nonevidence-based. Risk-adapted follow-up strategies incorporating cystoscopy and cross-sectional imaging accounting for individual patient factors should be implemented.

Stereo slit-scanning tomography of the anterior segment of the human eye

We demonstrate a new tomographic imaging device for 2D cross-sectional and 3D volumetric images of the anterior eye segment. The optical system combines optical sectioning with a stereoscopic camera setup to determine the true spatial location of the ocular structures. Moreover, we propose a calibration procedure to estimate the triangulation function that links the stereo camera pixel indices with the eye-referenced 3D spatial coordinates. The proposed instrument will image the entire anterior chamber and contiguous structures, including the corneal limbus, sclera and eyelids. Furthermore, the system can obtain corneal topography. Finally, we studied the repeatability of the instrument and its agreement with a commercial Scheimpflug imaging tomographer in a group of healthy subjects.

Utility of Abdominal Cross-Sectional Imaging in Motor Vehicle Accidents in an Inner City Trauma Center: A Retrospective Cohort Study

Utility of Abdominal Cross-Sectional Imaging in Motor Vehicle Accidents in an Inner City Trauma Center: A Retrospective Cohort Study

A DIC-FEM hybrid method for measuring strains near fiber-matrix interface of CFRP cross section

A DIC-FEM hybrid method is proposed to capture micro-scale deformation behavior near the fiber-matrix interface by combining displacement distributions measured using digital image correlation (DIC) with finite element method (FEM) analysis. Images of CFRP cross section with fine random pattern before and after deformation are taken with a laser microscope. The in-plane displacement components near the interface of fiber and matrix are obtained using digital image correlation and they are used as the input of the hybrid method. Not only the displacement distributions but the strain fields are determined using the proposed hybrid method, based on the superposition principle, so that the same distributions are obtained as those obtained by the measurement. The proposed DIC-FEM hybrid provides the strains near the interface between fiber and matrix, compensating for the insufficient resolution of microscope images.

Presence of Sonographic Secondary Signs Without Visualization of Appendix Is Indicative of Appendicitis in Children Younger Than 5 Years.

Diagnosis of acute appendicitis is more difficult in children aged 0-4 years due to atypical clinical presentation, leading to delay in diagnosis and higher incidence of complications. Nonvisualization of the appendix on ultrasound increases diagnostic challenge. We examined the utility of standardized reporting of sonographic secondary signs of appendicitis in children younger than 5 years with nonvisualization of the appendix. A retrospective cohort study of children younger than 5 years who underwent appendectomy following nonvisualization of the appendix on ultrasound from 2016 to 2022 was performed. Primary outcome was comparison of ultrasound and intraoperative findings. Two-sample t test and Wilcoxon sum-rank test compared continuous variables, and Fisher exact test compared categorical variables. Univariate and multivariate logistic regression analyses were performed to assess risk factors for complicated appendicitis in those with category 3 ultrasounds. Overall, 92 patients whose appendix was not visualized on ultrasound were included: 26 without secondary signs (category 2) and 66 with secondary signs (category 3). Significant differences in intraoperative findings between category 2 and category 3 patients existed (P < 0.001). On intraoperative assessment of patients with ultrasound category 2, 3.8% had no appendicitis, 46.2% had simple appendicitis, 34.6% had complicated appendicitis, and 15.4% underwent interval appendectomy. Conversely, of category 3 patients, 0% had no appendicitis, 7.6% had simple appendicitis, 48.5% had complicated appendicitis, and 43.9% underwent interval appendectomy. On logistic regression, in children with category 3 ultrasounds, presence of both fluid collection and free fluid as secondary signs was associated with intraoperative findings of complicated appendicitis. However, number of secondary signs was not significantly associated with increased likelihood of complicated appendicitis intraoperatively. Presence of secondary signs without visualization of the appendix was shown to be indicative of appendicitis, with high suspicion for complicated appendicitis, in patients younger than 5 years. Further validation of the presence of secondary signs on right-lower-quadrant ultrasound may lead to more expedient diagnosis, reduction in cross-sectional imaging, and earlier treatment of complicated appendicitis.

Exploring the Role of Intracorporeal Ultrasound in Partial Nephrectomies: A Systematic Review.

Renal cell carcinoma accounts for the sixth most common cancer in the United Kingdom. With the increasing application of cross-sectional imaging, the frequency of incidental renal masses has increased over time. Laparoscopic and robot-assisted partial nephrectomy has become the standard of care in the management of size and stage-appropriate renal masses. The objective of this systematic review was to analyse the surgical outcomes when intracorporeal ultrasound was utilised as an adjunct in partial nephrectomy. A comprehensive search in PubMed and Google Scholar was performed in July 2024 for publications in the English language. The primary endpoint was to evaluate the role of intracorporeal ultrasound as an adjunct in robotic partial nephrectomies and its impact on tumour clearance. After identifying 609 records, 52 records were screened and 44 records were sought for retrieval. Eight publications were included in this systematic review comprising 765 patients. Seven of the eight studies reported outcomes from single centres. The mean percentage of negative surgical margins was 97.6% (range = 92.1-100%). The use of intracorporeal ultrasound as an adjunct in partial nephrectomy for T1 renal cell cancer has proven to improve the rates of negative surgical margins thereby reducing the incidence of local recurrence and distant metastasis.

Alloplastic Vascular Grafts for Venous Interposition in Pancreatic Surgery: Readily Available and Reliable.

To investigate patency and clinical outcomes of alloplastic and other venous interposition graft materials in pancreatic surgery. Vascular pancreatic surgery is increasingly performed for locally advanced pancreatic neoplasms. Different than other centers, we prefer to use alloplastic vascular graft materials for superior mesenteric vein and portal vein interposition in pancreatic surgery. Advantages are off-the-shelf availability at any customizable length, different diameters, and ring-enforcement but proposed concerns are their thrombogenicity and fatal complications. Patients who underwent elective pancreatic resections with mesoportal venous interposition grafts (ISGPS type 4) between 2003-2022 were identified from the institutional pancreatectomy registry. Alloplastic vascular grafts imply synthetic materials, either based on polytetrafluorethylene (PTFE) or polyethylene terephthalate (PET). Surgical details, clinicopathological, and follow-up data were analyzed. The patients were followed for graft patency by cross-sectional imaging. In this study, 201 patients with venous interposition grafts were included (23% simultaneous arterial resections). Total pancreatectomy (41%) and pancreatoduodenectomy (35%) were the most frequent procedures. Vascular graft materials were alloplastic in 180 patients (83% PTFE and 17% PET) with a median diameter of 10mm and a median length of 33mm (measurement by CT scan). Patency rates among all graft materials at 7-, 30-, and 90-days were 99%, 93%, and 87%. Alloplastic grafts demonstrated superior patency over other materials (hazard ratio 2.7, P=0.009), and PTFE reached a 1-year patency of 78%. The all-cause 90-day mortality rate was 10%. No graft infection occurred. Alloplastic venous vascular grafts are safe and readily available tools in pancreatic surgery, especially for long-segmental mesoportal venous reconstructions.

Evaluation of coarse aggregate properties in hardened concrete based on segment anything model (SAM)

The applicability of the segment anything model (SAM) algorithm, a novel technique for analyzing the characteristics of coarse aggregate from RGB images of concrete cross-sections, was evaluated. Unlike traditional deep learning method, the SAM algorithm effectively and clearly separates coarse aggregate and mortar without requiring a large database, extensive pre-training, conversion of RGB images to grayscale, or manual threshold setting. Additionally, a new technique was applied to separate the pores recognized as aggregates by using the image difference according to the change in vertical and side lighting. Consequently, the area ratio of coarse aggregate, after the separation and removal of pores from the aggregate area, exhibited an error of approximately 7.0 % when compared to the actual volume ratio of the aggregate. However, in contrast to the calculation of the area ratio of coarse aggregate, the SAM algorithm demonstrated significant errors in size analysis, leading to distortions in the sieve curve. Nevertheless, the SAM algorithm indicates potential for application in various concrete-related fields of concrete in the future.

Neuroendocrine tumours and pregnancy: Real-world data from an European Neuroendocrine Tumour Centre of Excellence.

Neuroendocrine neoplasms (NENs) arise from the diffuse endocrine system and have been considered to be rare. However, the incidence and prevalence of these tumours have increased in recent years, and they are being seen in younger patients including women in the reproductive age group. Due to the paucity of data, diagnostic and therapeutic strategies in managing such tumours during pregnancy can be challenging to both treating physicians and patients. This article describes the experience and outcomes of managing pregnant women with NEN at a European Neuroendocrine Tumour Society (ENETS) Centre of Excellence. In this retrospective analysis, we evaluated a total of 22 pregnancies in 18 pregnant women with concurrent diagnoses of NENs who were managed at Royal Free Hospital ENETS Centre of Excellence throughout their pregnancy. These were identified from our tumour registry of 3500 NEN patients between 2015 and 2023. Cross-sectional imaging (computed tomography (CT)/magnetic resonance imaging (MRI)), pre- and post-pregnancy, for each patient was reviewed by an experienced radiologist. Tumour growth rate (TGR) was calculated using the formula: TGR = 100 × [exp (TG) - 1]; TG. [3 × log (D2/D1)]/time (months), where D1 is the tumour size at date 1; D2 is the tumour size at date 2; and time (months) = (Date 2 - Date 1 + 1)/30.44. Tumour growth rate pre-conception (TGRpc) and tumour growth rate post-partum (TGRpp) were calculated for each patient. In a sub-group of patients, positivity for oestrogen and progesterone receptors were analysed on the tumour tissue to evaluate whether the presence of these receptors affected tumour progression during the pregnancy. We also reviewed the pregnancy outcome in patients treated with somatostatin analogues during pregnancy. We analysed the data of a total 22 pregnancy encounters in 18 women: 15 pregnancies (68%) preceded the diagnosis of the NEN, whereas the diagnosis of NEN was made during pregnancy or in the post-partum period in 5 (23%) and 2 (9%) pregnancies respectively. Eight patients (44%) had a diagnosis of a pancreatic NEN, whereas 5 (28%) were diagnosed with mid-gut NENs, and a further 5 at other sites. The majority of the patients (n = 12, 67%) had evidence of metastatic disease at the time of diagnosis. Most pregnancies had a successful outcome (n = 19, 86%), whereas 3 patients (14%) had miscarriages in the 1st trimester. Five patients in total of 6 pregnancies were treated with somatostatin analogues as monotherapy during the pregnancy, and all of them had stable disease after pregnancy. All of them delivered healthy babies without any side effects or complications due to therapy. The average TGRpc was -0.8% (n = 5) and the average TGRpp was +0.96% (n = 6); 2 patients who did not have suitable targets for calculation of TGRpc developed new lesions suggesting disease progression. Moreover, 2 of the 4 patients who have had both pre-conception and post-pregnancy scans showed an increase in TGRpp compared to TGRpc. The management of NENs during pregnancy should be multidisciplinary with an individualised approach to each patient. Somatostatin analogues appear to be safe during pregnancy, though further robust studies are needed. Pregnancy per se may accelerate tumour progression, and patients should be counselled regarding this possibility.

Paraganglioma With Intracranial Invasion Demonstrated on 68Ga-DOTATATE PET/CT.

68Ga-DOTATATE PET/CT demonstrates superior sensitivity compared with other cross-sectional and functional imaging techniques in detecting head and neck paragangliomas. It is the primary recommended imaging modality for the evaluation of head and neck paragangliomas, especially in patients suspected of having locally aggressive, multifocal, or metastatic disease, as well as those being considered for targeted peptide-receptor therapy. Herein, we demonstrate the 68Ga-DOTATATE PET/CT findings of a skull base paraganglioma with extensive local invasion and intracranial extension.

Sociodemographic predictors of imaging utilization in children with right lower quadrant pain.

Inequities in health care access lead to inequities in outcome. In recent years, health outcome disparities have been documented in children with acute appendicitis and sociodemographic predictors of imaging utilization have not been adequately assessed. The purpose of our study is to assess sociodemographic predictors for the diagnostic imaging of children with right lower quadrant (RLQ) pain. Our hypothesis is that disparities exist in imaging utilization. Our nationwide retrospective cohort study of the Pediatric Health Information System (PHIS) database queried emergency department encounters for children aged 0-18years presenting with RLQ pain (ICD code CM R10.31) between January 2018 and September 2023. Primary exposures included neighborhood-level sociodemographic metrics as measured by Child Opportunity Index, race/ethnicity, and insurance status. Outcomes included no diagnostic imaging, diagnostic imaging with radiography alone, ultrasonography (US), computed tomography (CT), and magnetic resonance imaging (MRI). Multivariable logistic regression analyses assessed modality usage with respect to the primary exposures after controlling for demographic (age, gender) and additional (hospital geographic region, time of imaging) covariates. To avoid the perpetuation of bias, reference categories were determined by the lowest numerical value for each covariate. In total, 100,161 patient encounters met inclusion criteria (mean patient age 11.2years ± 3.9; 59.3%, n = 59,416 females). Imaging utilized was US (78.0%; n = 78,115), CT (16.4%, n = 16,405), no imaging (13.9%, n = 13,894), radiography alone (4.4%, n = 4,429), and MRI (3.1%, n = 3,148). The most predictive factors for no imaging were moderate, low, and very low Child Opportunity Index (aOR 1.25, 1.17, and 1.18 [95% CI 1.10-1.33] compared to very high Child Opportunity Index); Black race/ethnicity (aOR 1.26 [95% CI 1.11-1.44] compared to White or Asian race/ethnicity); and public or other insurance (aOR 1.23 and 1.32 [95% CI 1.18-1.41] compared to commercial insurance). The most predictive factors for radiography alone were Black race/ethnicity (aOR 1.30 [95% CI 1.17-1.45] compared to Hispanic race/ethnicity) and public or other insurance (aOR 1.26 [95% CI 1.11-1.44] compared to commercial). The most predictive factors for US were very-high Child Opportunity Index (aOR 1.16 [95% CI 1.09-1.22] compared to very low Child Opportunity Index); Asian, NH-White, or Hispanic race/ethnicity (aOR 1.33, 1.31, 1.30 [95% CI 1.18-1.40] compared to Black race/ethnicity); and commercial insurance (aOR 1.20 [95% CI 1.16-1.25] compared to public insurance). The most predictive factor for CT was White race/ethnicity (aOR 1.26 [95% CI 1.11-1.43] compared with Asian race/ethnicity) and the most predictive factor for MRI was Hispanic race/ethnicity (aOR 1.49 [95% CI 1.17-1.61] compared with Black race/ethnicity). The greatest predictor of cross-sectional imaging was a hospital's region, with CT most likely in southern hospitals (aOR 4.09 [95% CI 2.17-7.70] compared with northeast hospitals). Patient Child Opportunity Index did not predict the likelihood of cross-sectional imaging with CT or MRI in tertiary pediatric centers. Sociodemographic disparities exist in the imaging of children presenting to tertiary pediatric hospitals with RLQ pain. Future studies are needed to analyze the causes of such disparities both on hospital and departmental levels.