Computed Tomography/computed Tomography Research Articles

Case Report: Gallstone ileus management - Case report and review of the literature

Gallstone ileus, a rare complication of cholelithiasis, presents significant morbidity and mortality challenges, with no established consensus on optimal management. This study aimed to highlight the complexities surrounding its occurrence and emphasize the need for tailored therapeutic strategies. An 88-year-old female, with a history of type 2 diabetes mellitus presented with diffuse abdominal pain and vomiting. Clinical evaluation revealed signs of small-bowel obstruction. Radiological assessments, including Computed Tomography CT) scans, confirmed biliary ileus, showcasing a sizable gallstone causing subacute obstruction. Emergency surgery involving enterolithotomy was performed, successfully addressing the immediate concerns. Postoperative follow-up demonstrated a one-year asymptomatic period, emphasizing the effectiveness of the chosen intervention. Gallstone ileus typically follows acute cholecystitis, leading to gallstone erosion and fistula formation commonly in the duodenum. Diagnosis is challenging because of nonspecific symptoms, necessitating a high index of suspicion. Computed tomography (CT) plays a pivotal role in accurate and rapid diagnoses. This study delves into the intricate details of gallstone ileus presentation, complications, and the debate surrounding optimal surgical management, acknowledging the effectiveness of the two-stage procedure and emerging laparoscopic approaches. This case provides valuable insights into the intricate facets of gallstone ileus and emphasizes the need for individualized treatment strategies. Successful management, as demonstrated in our case, underscores the importance of considering patient-specific factors when choosing between the surgical approaches. This study supports recent reports advocating for laparoscopic interventions, encouraging further exploration of evolving therapeutic modalities for gallstone ileus.

Tc-99m-MDP Uptake in Extraosseous Metastases from Ovarian Papillary Serous Adenocarcinoma.

The uptake of Tc-99m-uptake of Tc-99m-methylene diphosphonate (MDP) on bone scintigraphy can be seen at sites other than bone in a varying number of benign and malignant conditions. Extraosseous metastatic calcifications can occur in ovarian papillary serous adenocarcinoma (PSAC). These extraosseous calcifications show Tc-99m-MDP uptake. We report a case of a female in her sixties who had a previous history of PSAC of the ovary. The patient had undergone neoadjuvant chemotherapy (NACT) followed by total abdominal hysterectomy and bilateral salpingo-oophorectomy. She also received adjuvant chemotherapy. Tc-99m-MDP bone scan was performed post chemotherapy because the patient complained of lower backache. The scan showed increased uptake in the lower thoracic and lumbar vertebral regions. However, single-photon emission computed tomography/computed tomography (CT) localizes the uptake to metastatic calcified peritoneal deposits. Further 18F-fluorodeoxyglucose positron emission tomography/CT confirmed widespread peritoneal and omental metastatic disease with increased uptake.

AI-Defined Cardiac Anatomy Improves Risk Stratification of Hybrid Perfusion Imaging

BackgroundComputed tomography attenuation correction (CTAC) improves perfusion quantification of hybrid myocardial perfusion imaging by correcting for attenuation artifacts. Artificial intelligence (AI) can automatically measure coronary artery calcium (CAC) from CTAC to improve risk prediction but could potentially derive additional anatomic features. ObjectivesThe authors evaluated AI-based derivation of cardiac anatomy from CTAC and assessed its added prognostic utility. MethodsThe authors considered consecutive patients without known coronary artery disease who underwent single-photon emission computed tomography/computed tomography (CT) myocardial perfusion imaging at 3 separate centers. Previously validated AI models were used to segment CAC and cardiac structures (left atrium, left ventricle, right atrium, right ventricular volume, and left ventricular [LV] mass) from CTAC. They evaluated associations with major adverse cardiovascular events (MACEs), which included death, myocardial infarction, unstable angina, or revascularization. ResultsIn total, 7,613 patients were included with a median age of 64 years. During a median follow-up of 2.4 years (IQR: 1.3-3.4 years), MACEs occurred in 1,045 (13.7%) patients. Fully automated AI processing took an average of 6.2 ± 0.2 seconds for CAC and 15.8 ± 3.2 seconds for cardiac volumes and LV mass. Patients in the highest quartile of LV mass and left atrium, LV, right atrium, and right ventricular volume were at significantly increased risk of MACEs compared to patients in the lowest quartile, with HR ranging from 1.46 to 3.31. The addition of all CT-based volumes and CT-based LV mass improved the continuous net reclassification index by 23.1%. ConclusionsAI can automatically derive LV mass and cardiac chamber volumes from CT attenuation imaging, significantly improving cardiovascular risk assessment for hybrid perfusion imaging.

Findings of I-131 SPECT/CT, 18F-FDG, and 68Ga-FAPI-04 PET/CT Imaging in a Patient Treated with Radioiodine Therapy for Metastatic Papillary Thyroid Carcinoma.

A 50-year-old man undergone total thyroidectomy and histopathology revealed papillary thyroid carcinoma with a tumor size of 4.5 cm. The patient was referred to a nuclear medicine clinic for radioiodine therapy. Since the thyroglobulin level before the treatment was 495 ug/L, low-dose (185 MBq) I-131 scan was performed. In addition to multiple liver metastases, bone metastases were detected in the sacrum and right 7th rib in I-131 whole body scanning and single photon emission computed tomography/computed tomography (CT) imaging at the time of initial staging. We present a case of multiple metastatic papillary thyroid carcinoma whose radioiodine treatment response and clinical outcome were evaluated with 18F-fluorodeoxyglucose and Gallium-68 FAPI-04 positron emission tomography/CT.

The effect of percutaneous tract dilation technique on renal parenchymal trauma: An experimental in vivo study on a porcine model.

The purpose of this study was to evaluate renal parenchymal trauma of two-step dilation compared to the conventional Amplatz gradual dilation during percutaneous nephrolithotomy on a porcine model. A nonpapillary percutaneous access tract was established under fluoroscopic guidance in both kidneys of four female pigs. On the right kidney of each pig, gradual dilation was performed using an Amplatz dilator set with a gradual dilation to 30 Fr, whereas on the left, a two-step dilation was utilized using only 16 Fr and 30 Fr dilators. Two of the animals were euthanized immediately after the procedure and the remaining two 1 month later. The pigs that were kept alive underwent a contrast-enhanced computed tomography immediately, 15, and 30 days postoperatively. A dimercaptosuccinic acid (DMSA) scintigraphy and single-photon emission computed tomography-computed tomography (CT) were also performed after the last CT and afterward, the pigs were sacrificed. All kidneys were harvested for pathohistological examination. The follow-up radiologic imaging showed similar parenchymal damage caused by the compared dilation techniques and an expected reduction in scar size in the later scans. No scar was identified by DMSA in any kidney. Gross and microscopic examinations conducted both on the kidneys that were harvested immediately after the procedure and the ones from the animals that were left to heal, revealed no significant differences in tissue damage, grade of fibrosis, or inflammation depending on the dilation method. Our study showed no inferior outcomes caused by two-step dilation compared to gradual dilation regarding renal parenchymal damage following a nonpapillary puncture. In fact, postoperative imaging findings suggested a trend toward better healing and less scar tissue when the two-step method was used.

Nasolacrimal Duct Obstruction on 131I SPECT/CT: Atypical False-positive Paranasal Radioiodine Uptake as a Complication of Single-dose RAI Treatment.

Nasolacrimal duct obstruction (NLDO) is a rare complication after radioiodine therapy and may cause false positive 131I uptake at the point of obstruction in 131I whole body scan. Here, we report a 59-year-old female patient with papillary thyroid cancer treated with total thyroidectomy followed by 131I therapy. 131I whole body scan revealed focal uptake in the head. Single photon emission computed tomography/computed tomography (CT) showed focal uptake at the right proximal nasolacrimal duct. The ophthalmologic examination and the diagnostic maxillofacial CT confirmed the diagnosis of NLDO.

Evaluation of Congenital Mediastinal Vascular Anomaly Types And Frequencies Among 2000 Cases

Aim: Congenital vascular malformations of the thorax are not very common. These conditions are mostly asymptomatic and detected incidentally on imaging performed for various complaints. In this study, it is aimed to examine the incidence of congenital thoracic vascular anomalies in our region.Methods: The features of the patients with non-specific complaints who underwent a thorax Computed Tomography (CT) for over 2 years period were retrospectively reviewed on the hospital database and demographical data (Gender and age) were recorded. All the Computed Tomography CT images were interpreted regarding thoracic vascular anomalies including persistent left superior vena cava, azygos lobe, aberrant right subclavian artery, dilated left superior intercostal vein, right-sided aortic arch, situs inversus, and partial anomalous pulmonary venous return. The incidences of these thoracic vascular anomalies were calculated and compared with previous studies. Results: A total of 2000 patients with a mean age of 56.13±14.62 (12-93 years) were included in this study. Among them 776 (38.8%) ones were female (mean age 56.93±15.19 (13-93 years)) and 1224 (61.2%) were male (mean age 55.63±14.23 (12-88 years)). Mediastinal vascular anomaly was detected in 62 (3.1%) patients. A mediastinal vascular anomaly was observed in 27 (3.5%) female patients and 35 (2.6%) male patients. The most common mediastinal vascular anomaly inthis study was the right aberrant subclavian artery (n:17, 0.9%) and the rarest was partial anomalous pulmonary venous return (n:1, 0.1%). Persistent left superior vena cava incidence was 0.3% (n:6), azygos lobe 0.7% (n:14), right-sided aortic arch 0.3% (n:5), situs inversus totalis 0.2% (n:3), and dilated left superior intercostal vein 0.8% (n:16).Conclusion: Mediastinal vascular anomalies are rare and usually asymptomatic. But the imaging findings of these conditions must be well-known to accurately planning the interventions and also to prevent iatrogenic injuries.

Long-term follow-up study of post-COVID-19 patients

To evaluate dynamic changes in the lungs, hemostasis system, immune system in different terms after coronavirus pneumonia. Ventilation-perfusion single-photon emission computed tomography/computed tomography (CT), functional methods of lung investigation, evaluation of hemostasis system, immune status and specific humoral immune response were performed and evaluated in different terms after coronavirus pneumonia. A total of 71 patients were examined according to this protocol. We examined patients with the lesion volume not less than 50% according to chest CT. All patients were divided into 2 groups depending on the distance from the acute stage of coronavirus pneumonia. Group 1 included patients who were examined early (3060 days after hospital discharge), group 2 included patients who were examined later (61180 days after hospital discharge). We obtained gradual regression of pathologically-modified tissue from 67.3% during the inpatient phase to 30.9% during the early period and to 19.7% during the late period of examination, according to CT scan of the chest organs. The same tendency was demonstrated by diffusion capacity of the lungs. Perfusion scintigraphy data showed a decrease in perfusion deficit from 26.012.8% during the early period of examination to 19.46.2% during the late period of examination. On the contrary, ventilatory scintigraphy demonstrates the increase of isotope passage time through the alveolar-capillary membrane over time (from 48.231.3 minutes in the early period to 83.637.2 minutes in the late period). An increase in D-dimer was detected in 24% of patients in the early group. The levels of inflammatory markers, indices of immune status, and specific humoral immune response did not differ in the two described groups. The results demonstrate gradual regression of pathological changes caused by coronavirus infection.

The Prevalence of Odontogenic Pathology in Patients With Bilateral Rhinosinusitis.

ObjectiveWe investigated cases with opacification on maxillary sinus computed tomography (CT) among patients with rhinosinusitis with opacification in both paranasal sinuses (bilateral rhinosinusitis) to confirm the involvement of odontogenic infections.MethodsThis study included 75 patients who were diagnosed with bilateral rhinosinusitis based on clinical examination and evident opacification on at least one side on maxillary sinus imaging with computed tomography CT. The definition of odontogenic sinusitis was determined by examining EPT and oral findings, in addition to the CT and orthopantomography (OP), by one oral surgeon and two otolaryngologists.ResultsWe found that 45.3% of patients had odontogenic infections, which were associated with multiple infected teeth in some cases. Odontogenic infection was observed in both sinuses in some patients. Sinusitis with polyps was frequently associated with dental infection, and some cases were also associated with mycosis. Almost no oral symptoms were observed.ConclusionsThe results suggest that clinicians should consider odontogenic infection in patients with bilateral rhinosinusitis with opacification, on at least one side on maxillary sinus imaging. This means that accurate diagnosis may be challenging for otolaryngologist or dentists alone, suggesting that a collaboration between the two would be suitable for this task.

Single-domain antibodies for radio nuclear imaging and therapy of esophageal squamous cell carcinoma: a narrative review

Abstract Single-domain antibodies have the characteristics of small molecular weight, strong tissue penetration, and high affinity, and are widely used to construct molecular probes for disease diagnosis and treatment. This article reviews molecular imaging studies including positron emission tomography (PET), single-photon emission computed tomography/computed tomography (CT), PET/CT, and fluorescent imaging of molecular probes composed of single-domain antibodies against eight esophageal squamous cell carcinoma biological targets. These 8 targets are highly expressed on the membrane of esophageal squamous cell carcinoma cells and include epidermal growth factor receptor, human epidermal growth factor receptor 2, human epidermal growth factor receptor 3, hepatocyte growth factor receptor, vascular endothelial growth factor receptor 2, chemokine receptor 4, chemokine receptor 7, and carcinoembryonic antigen. The current problems and solutions are also discussed to provide a reference for future design of molecular imaging probes targeting esophageal squamous cell carcinoma.

Prediction of quality of life by Helsinki computed tomography scoring system in patients with traumatic brain injury

ABSTRACT Purpose The aim of this study is to assess the association between the Computed Tomography (CT) findings on admission, according to the Helsinki computed tomography CT score, and patient’s Quality of Life (QoL) following traumatic brain injury (TBI) in Lebanon. Methods A retrospective study was performed on 49 males suffering from war induced TBI. Participants were stratified into two groups based on the date of injury. Helsinki CT score was calculated for CT scans of participants. Outcomes were assessed using QoL scales including the Project for the Epidemiological Analysis of Critical Care Patients scale (PAEEC). Results Correlation analysis showed that QoL, up to 4 years post-TBI, was significantly associated with Helsinki CT classification. Group 1 of subjects living with TBI for 1–2 years revealed a correlation coefficient r = 0.536, p-value = 0.027, whereas, group 2 including subjects who are injured since 3–4 years, had a correlation coefficient r = 0.565, p-value = 0.001. Conclusion The present study showed that patients with traumatic brain injury experienced significant quality of life deterioration up to 4 years post-TBI. Our findings propose the important role of Helsinki score in predicting the quality of life among patients with TBI.

SPECT Imaging of Muscle Injury with [99mTc]MDP in a Mouse Model of Muscular Dystrophy

PurposeTc-99m methylene diphosphonate ([99mTc]MDP) is an in vivo bone imaging agent that also accumulates in injured skeletal muscle cells. The objective of this study was to investigate if [99mTc]MDP could be used to detect muscle injury in the mdx mouse model of Duchenne muscular dystrophy (DMD).ProceduresStatic whole-body single-photon emission computed tomography/computed tomography (CT) scans were acquired at 2 h post-injection of [99mTc]MDP in two cohorts of animals at different sites: one cohort of mice at 6, 15, and 19 weeks of age, and a separate cohort at 16 weeks. The second cohort was also imaged with high-resolution CT at 8 weeks.Resultsmdx mice had higher [99mTc]MDP uptake and significantly higher [99mTc]MDP concentrations in muscle than controls.ConclusionsHigher uptake of [99mTc]MDP in muscle of mdx mice agrees with histological reports of muscle calcification in mdx mice, and suggests the potential translational use of [99mTc]MDP imaging for tracking DMD progression and therapeutic response.

Incidental Detection of Perinephric Urinary Leak on Bone Scintigraphy in a Patient with Urinary Bladder Carcinoma.

A 71-year-old male patient with urothelial carcinoma of the bladder was referred for 99mTc-methylene diphosphonate bone scintigraphy to assess for skeletal metastasis. While the bone scan showed no abnormal skeletal uptake, tracer activity was detected in the extrarenal region of the left renal fossa on the planar image; single photon emission computed tomography-computed tomography (CT) demonstrated tracer pooling in the perirenal collection. In addition, the CT detected nontracer-avid parenchymal lung nodules and hypodense liver lesions consistent with metastatic disease. The perinephric urinary leak was drained by percutaneous drainage, confirmed by diuretic renography the following day.

Papel del estudio radiológico multimodal en el código ictus

In stroke code patients, multimodal imaging workup encompasses various imaging techniques, including baseline computed tomography (CT), magnetic resonance (MR) imaging, diffusion MR imaging, CT or MR perfusion studies, and CT or MR angiography, that are used to rule out bleeding, confirm arterial occlusion, establish tissue viability, and help select candidates for endovascular treatment as early as possible. Five recently published relevant clinical trials have demonstrated the efficacy of mechanical thrombectomy in proximal arterial occlusions; all these trials used different imaging techniques to select patients. Analyzing these trials and the scientific literature, we conclude that conventional CT interpreted with the Alberta Stroke Programme Computed Tomography Score (ASPECTS) and CT or MR angiography should always be used (level of evidence I, grade of recommendation A) and that CT and MR perfusion studies are useful in specific circumstances.

Nuclear medicine imaging in osteonecrosis of hip: Old and current concepts.

Osteonecrosis (ON) is caused by inadequate blood supply leading to bone death, which results in the collapse of the architectural bony structure. Femoral head is the most common site involved in ON. Magnetic resonance imaging (MRI) is a commonly used imaging modality to detect early ON. When MRI is inconclusive, bone scan is helpful in detecting ON during early phase of the disease. As newer nuclear medicine equipment, like single photon emission computed tomography/computed tomography (CT) and positron emission tomography/CT, are emerging in medical science, we review the role of these imaging modalities in ON of femoral head.

Molecular imaging in neuroendocrine tumors: recent advances, controversies, unresolved issues, and roles in management.

The purpose is to review recent advances in molecular imaging of neuroendocrine tumors (NETs), discuss unresolved issues, and review how these advances are affecting clinical management. Molecular imaging of NETs underwent a number of important changes in the last few years, leading to some controversies, unresolved issues, and significant changes in clinical management. The most recent changes are reviewed in this article. Particularly important is the rapid replacement in somatostatin receptor scintigraphy of In-diethylenetriamine penta-acetic acid-single-photon emission computed tomography/computed tomography (CT) by Ga-fluorodopa(F-D)PA), 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA)-peptide-PET/CT imaging, which is now approved in many countries including the USA. Numerous studies in many different types of NETs demonstrate the greater sensitivity of Ga-DOTA-peptide PET/CT, its high specificity, and its impact on management. Other important developments in somatostatin receptor scintigraphy/molecular imaging include demonstrating the prognostic value of both Ga-DOTA-peptide PET/CT and F-fluoro-deoxyglucose PET/CT; how their use can be complementary; comparing the sensitivities and usefulness of Ga-DOTA-peptide PET/CT and F-FDOPA PET/CT; introducing new linkers and radiolabeled ligands such as Cu-DOTA-peptides with a long half-life, enhancing utility; and the introduction of somatostatin receptor antagonists which show enhanced uptake by NETs. In addition, novel ligands which interact with other receptors (GLP-1, bombesin, cholecystokinin, gastric inhibitory polpeptide, integrin, chemokines) are described, which show promise in the imaging of both NETs and other tumors. Molecular imaging is now required for all aspects of the management of patients with NETs. Its results are essential not only for the proper diagnostic management of the patient, but also for assessing whether the patient is a candidate for peptide receptor radionuclide therapy with Lu and also for providing prognostic value.

⁹⁹mTc-anti-TNF-α antibody for the imaging of disease activity in pulmonary sarcoidosis.

Infliximab, a monoclonal antibody directed against tumour necrosis factor (TNF)-α, is used in the treatment of refractory sarcoidosis. However, the clinical response is variable and a tool to select responders beforehand is highly desirable. In this study we evaluated scintigraphy with technetium-99m ((99m)Tc)-labelled infliximab for the imaging of disease activity in patients with pulmonary sarcoidosis.10 patients were studied using single photon emission computed tomography/computed tomography (CT) 6 h and 20 h after intravenous administration of 370 MBq of(99m)Tc-infliximab. Correlation analysis was performed between tissue accumulation of(99m)Tc-infliximab and laboratory parameters (including soluble interleukin-2 receptor and angiotensin-converting enzyme), lung function parameters (including forced expiratory volume in 1 s and the diffusing capacity of the lung for carbon monoxide) and(18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/CT.Analysis showed selective and variable accumulation of(99m)Tc-infliximab in the target tissue. Accumulation correlated positively with all four laboratory parameters and negatively with all four lung function parameters, yielding better correlations than serum TNF-α levels or(18)F-FDG PET/CT.(99m)Tc-infliximab accumulation reflects thein situTNF-α expression in an individual patient and therefore provides valuable information on the presence of the biological target for anti-TNF-α therapy.

Metastatic mimics on bone scan: "All that glitters is not metastatic".

In this pictorial review, cases where benign diseases caused a diagnostic dilemma on bone scan are illustrated. This review highlights the value of correlative imaging- single-photon emission computed tomography/computed tomography (CT), CT, and magnetic resonance imaging in solving the diagnostic problem by exact localization and characterization of the lesions. All these eventually lead to increased diagnostic confidence, better and more accurate reporting and avoidance of delay in initiation of treatment due to equivocal results. The imaging features of these benign pathologies – which are “mimics of metastatic disease,” are elaborated so that the reader can incorporate them while reporting so as to avoid mis-interpretations.

Accurate Assessment of Aortic Stenosis

Aortic valve (AV) stenosis is one of the most common valvular diseases and is the third most common cardiovascular disease in developed countries. It occurs in ≈2.8% of patients ≥75 years of age and can occur because of degenerative calcification and congenital valvular defects such as bicuspid AVs or rheumatic disease.1–3 Calcific aortic stenosis (AS) is associated with increased leaflet stiffness and a narrowed AV orifice, resulting in increased pressure gradients across the valve. The presence of a bicuspid AV significantly increases the risk of AS.4 The natural history of AS is a prolonged asymptomatic period, with progressive reduction of the AV orifice area due to sclerosis initially, culminating in calcific AS. This is accompanied by a corresponding increase in the transaortic pressure gradient (Δ P ) and myocardial pressure overload. Through the preload reserve, the left ventricle (LV) compensates for the increased workload until the sarcomeres stretch to their maximum diastolic length. Once the preload reserve is exhausted, increases in afterload are accompanied by a reduction in stroke volume (SV), resulting in afterload mismatch. Ultimately, this causes LV hypertrophy, associated with an enlargement of cardiac myocytes and increased LV wall thickness.5 Initial diagnosis of AS typically occurs during routine physical examination with the presence of a heart murmur, click, or other abnormal sounds, but undiagnosed patients may experience the onset of severe symptoms such as angina, syncope, and heart failure. Without intervention, patient mortality typically occurs within 5 years of the onset of symptoms.6–11 Multiple studies and reviews have focused on the clinical aspects of this disease, including disease progression, markers of disease severity, treatment guidelines, and outcomes.1–3,6,12–16 Very few reviews have focused on the hemodynamic principles underlying AS and on comparing data obtained across different …

Correlation between morphological and functional liver volume in each sector using integrated SPECT/CT imaging by computed tomography and technetium-99m galactosyl serum albumin scintigraphy in patients with various diseases who had undergone hepatectomy

The aim of the study was to accurately examine the functional volume (RI-vol) of the hepatic segments on single photon emission computed tomography/computed tomography (CT) fusion imaging by technetium-99m galactosyl human serum albumin scintigraphy and compare it with the RI-vol and morphological volume obtained on computed tomography (CT-vol). In 60 patients with various liver background statuses who had undergone hepatectomy, the RI-vol and CT-vol were examined in each sector using imaging analysis. The values from a control group (n=91) were used as reference data. The mean RI-vol and CT-vol of the right liver were 64 ± 10 and 63 ± 6%, respectively, whereas the values for the left liver were 36 ± 10 and 37 ± 6%, respectively. Compared with the control group, the ratios in each hemiliver were similar. The mean RI-vol and CT-vol for each sector were also similar, and significant positive correlations were identified between the two volumes (P<0.01). In four patients with hepatic tumors involving the main hepatic vessels or the bile duct and in 10 patients who had undergone portal vein embolization, the actual RI-vol in the injured sector was significantly decreased compared with CT-vol (P<0.05). There were marked changes in functional volume in segment 6+7 and segment 2+3 after portal vein embolization (P<0.05). Volumetric measurement using single photon emission computed tomography/CT imaging with technetium-99m galactosyl human serum albumin scintigraphy is useful for evaluating the functional volume in separated livers and offers a good reflection of the background liver status.