Artificial Intelligence-based CT Assessment of Bronchiectasis: The COPDGene Study.

Background CT is the standard method used to assess bronchiectasis. A higher airway-to-artery diameter ratio (AAR) is typically used to identify enlarged bronchi and bronchiectasis; however, current imaging methods are limited in assessing the extent of this metric in CT scans. Purpose To determine the extent of AARs using an artificial intelligence-based chest CT and assess the association of AARs with exacerbations over time. Materials and Methods In a secondary analysis of ever-smokers from the prospective, observational, multicenter COPDGene study, AARs were quantified using an artificial intelligence tool. The percentage of airways with AAR greater than 1 (a measure of airway dilatation) in each participant on chest CT scans was determined. Pulmonary exacerbations were prospectively determined through biannual follow-up (from July 2009 to September 2021). Multivariable zero-inflated regression models were used to assess the association between the percentage of airways with AAR greater than 1 and the total number of pulmonary exacerbations over follow-up. Covariates included demographics, lung function, and conventional CT parameters. Results Among 4192 participants (median age, 59 years; IQR, 52-67 years; 1878 men [45%]), 1834 had chronic obstructive pulmonary disease (COPD). During a 10-year follow-up and in adjusted models, the percentage of airways with AARs greater than 1 (quartile 4 vs 1) was associated with a higher total number of exacerbations (risk ratio [RR], 1.08; 95% CI: 1.02, 1.15; P = .01). In participants meeting clinical and imaging criteria of bronchiectasis (ie, clinical manifestations with ≥3% of AARs >1) versus those who did not, the RR was 1.37 (95% CI: 1.31, 1.43; P < .001). Among participants with COPD, the corresponding RRs were 1.10 (95% CI: 1.02, 1.18; P = .02) and 1.32 (95% CI: 1.26, 1.39; P < .001), respectively. Conclusion In ever-smokers with chronic obstructive pulmonary disease, artificial intelligence-based CT measures of bronchiectasis were associated with more exacerbations over time. Clinical trial registration no. NCT00608764 © RSNA, 2022 Supplemental material is available for this article. See also the editorial by Schiebler and Seo in this issue.

Evaluation of Iodine-125 Interstitial Brachytherapy Using Micro-Positron Emission Tomography/Computed Tomography with 18F-Fluorodeoxyglucose in Hepatocellular Carcinoma HepG2 Xenografts.

BACKGROUND Iodine-125 interstitial brachytherapy (125I-IBT) is a promising treatment option for unresectable hepatocellular carcinoma (HCC). This study evaluated the usefulness of micro-positron emission tomography/computed tomography (micro-PET/CT) with 18F-fluorodeoxyglucose (18F-FDG) in assessing response to 125I-IBT in HCC HepG2 xenograft. MATERIAL AND METHODS Twelve mice with bilateral HepG2 xenografts were divided into 3 equal groups implanted with iodine-125 seeds into the left xenografts with a dose of 30, 50, and 80 Gy, respectively, and the right xenografts were used as internal controls. Before and 28 days after treatment, the 18F-FDG micro-PET/CT was performed. The ratios of left to right xenografts of tumor volume (RTV), maximum standardized uptake value (RSUVmax), mean optical density of caspase-3 expression (RMODcaspase-3), and apoptosis index (RAI) were compared. RESULTS The RTV means of the 50 and 80 Gy groups were significantly lower than in the 30 Gy group after treatment (P<0.01) and the RTV means after treatment were lower than baseline in the 50 and 80 Gy groups (P<0.05). The RSUVmax mean after treatment was lower than baseline in the 80 Gy group (P<0.05). The RMODCaspase-3 and RAI means of the 80 Gy group were higher than in the 30 Gy group (P<0.05). The RSUVmax was correlated negatively to RMODcaspase-3 (r=-0.624, P<0.05) and RAI (r=-0.651, P<0.05). CONCLUSIONS This study suggest that 125I-IBT inhibits tumor growth via upregulating caspase-3 expression and prompting apoptosis in HCC HepG2 xenografts. The 18F-FDG micro-PET/CT may be a useful functional imaging modality to assess early response to 125I-IBT in HCC HepG2 xenograft.

Utility of Radionuclide Bone Scintigraphy in Complex Regional Pain Syndrome.

PURPOSE OF REVIEW: To describe the current understanding of the role of three-phase bone scintigraphy (TPBS) in the diagnosis and management of complex regional pain syndrome (CRPS), discuss its advantages and limitations, and present three examples of TPBS patterns typically seen in CRPS patients. RECENT FINDINGS: CRPS is a debilitating disorder frequently presenting with pain to ordinarily non-painful stimuli, redness, swelling, following fractures, stroke, myocardial infarction, surgery, or even minor trauma, and its diagnosis, based on clinical criteria and supportive imaging findings, is difficult. Of the available adjunctive diagnostic imaging modalities, radionuclide bone scintigraphy using a TPBS protocol is the most sensitive and specific for detecting abnormalities commonly seen with this condition-classically, increased periarticular uptake on delayed phase of TPBS, with variable increased uptake on perfusion phases, depending on chronicity. Recent studies have (1) demonstrated a more heterogeneous correlation of TPBS findings with CRPS diagnosis using the current Budapest criteria than in studies using older criteria, (2) pointed to the utility of novel quantitative scintigraphic techniques, and (3) highlighted the value of the early perfusion phases of TPBS in predicting treatment response. TPBS remains a valuable imaging adjunct to clinical diagnosis of CRPS. In combination with a multi-modal analgesic approach, TPBS can be used to follow disease course and potentially treatment response, although prospective trials are needed to further delineate its role.

[State of the venous outflow from the small pelvis after surgical correction of pelvioperineal reflux]. / Sostoianie venoznogo ottoka iz malogo taza posle khirurgicheskoi korrektsii pel'vio-perineal'nogo refliuksa.

OBJECTIVE: The study was aimed at assessing the venous outflow from the small pelvis after surgical correction of pelvioperineal reflux with the use of reference methods of examination. PATIENTS AND METHODS: We examines a total of 43 female patients (aged 41.5±5.2 years) presenting with pelvic varicose veins and subjected to phlebectomy on the external genitalia, perineum and lower limbs. All women had no evidence of pelvic venous plethora. All women underwent the following examinations: ultrasonographic angioscanning of pelvic and lower-limb veins, emission computed tomography of pelvic veins prior to operation, as well as 1, 6 and 12 months after surgical interventions. We evaluated efficacy of phlebectomy in elimination of pelvioperineal reflux and varicose syndrome, the frequency of detecting valvular insufficiency of pelvic and lower-limb veins, dynamics of the coefficient of pelvic congestion syndrome in the immediate and remote postoperative periods. RESULTS AND DISCUSSION: No cases of relapses of valvular, perineal varicosity, repeat appearance of varicose veins on the lower extremities, occurrence of signs of pelvic venous congestion were revealed. The frequency of detecting valvular insufficiency of the parametrial, uterine, gonadal and iliac veins remained unchanged. The coefficient of pelvic congestion syndrome did not alter either (Cpcs=0.8±0.11 at baseline versus Cpcs=0.78±0.1 after 12 months). CONCLUSION: The obtained results are indicative of a steady state of the venous outflow from the small pelvis in women with pelvic varicose veins and pelvioperineal reflux after surgical removal of vulvar, perineal and superficial femoral veins.

Nuclear medicine imaging of multiple myeloma, particularly in the relapsed setting.

Multiple myeloma (MM) is characterized by a monoclonal plasma cell population in the bone marrow. Lytic lesions occur in up to 90 % of patients. For many years, whole-body X-ray (WBX) was the method of choice for detecting skeleton abnormalities. However, the value of WBX in relapsing disease is limited because lesions persist post-treatment, which restricts the capacity to distinguish between old, inactive skeletal lesions and new, active ones. Therefore, alternative techniques are necessary to visualize disease activity. Modern imaging techniques such as magnetic resonance imaging, positron emission tomography and computed tomography offer superior detection of myeloma bone disease and extramedullary manifestations. In particular, the properties of nuclear imaging enable the identification of disease activity by directly targeting the specific cellular properties of malignant plasma cells. In this review, an overview is provided of the effectiveness of radiopharmaceuticals that target metabolism, surface receptors and angiogenesis. The available literature data for commonly used nuclear imaging tracers, the promising first results of new tracers, and our pilot work indicate that a number of these radiopharmaceutical applications can be used effectively for staging and response monitoring of relapsing MM patients. Moreover, some tracers can potentially be used for radio immunotherapy.

Cardiovascular magnetic resonance myocardial T1 mapping to detect and quantify cardiac involvement in familial amyloid polyneuropathy.

OBJECTIVES: This study sought to explore the potential role of non-contrast T1 mapping for the detection and quantification of cardiac involvement in familial amyloid polyneuropathy (FAP). METHODS: Japanese patients with FAP [n = 41, age 53.2 ± 13.9 years, genotype Val30Met (n = 25), non-Val30Met (n = 16)] underwent cardiac magnetic resonance imaging that included T1 mapping (saturation-recovery method) and late gadolinium-enhanced (LGE) imaging on a 3.0-T MR scanner. Their native T1 was measured on mid-ventricular short-axis images and compared with 30 controls. RESULTS: Of the 41 FAP patients 29 were LGE positive. The native T1 was significantly higher in FAP patients than in the controls (1,634.1 ± 126.3 ms vs. 1,432.4 ± 69.0 ms, p < 0.01), significantly higher in LGE-positive- than LGE-negative FAP patients (1,687.1 ± 104.4 ms vs. 1,505.4 ± 68.5 ms, p < 0.01), and significantly higher in LGE-negative FAP patients than the controls (p < 0.01). A native T1 cutoff value of 1,610 ms yielded 85.4% accuracy for identifying LGE-positive FAP. The native T1 significantly correlated with the interventricular septum wall thickness, the left ventricular mass, the LGE volume, the plasma B-type natriuretic peptide level, and the E/e' ratio (all p < 0.01). CONCLUSION: T1 mapping is of high diagnostic accuracy for the detection of LGE-positive FAP. The native myocardial T1 may be correlated with the severity of cardiac amyloid deposition. KEY POINTS: • The native T1 was higher in FAP patients than the controls. • The native T1 was higher in LGE-positive- than LGE-negative FAP patients. • The native T1 was higher in LGE-negative FAP patients than the controls. • The native T1 correlated with clinical markers of systolic and diastolic dysfunction. • Myocardial T1 mapping is of high diagnostic accuracy for detecting LGE-positive FAP.

Multi-modality imaging: Bird's eye view from the 2016 American Heart Association Scientific Sessions.

This review summarizes key imaging studies that were presented in the American Heart Association Scientific Sessions 2016 related to the fields of nuclear cardiology, cardiac computed tomography, cardiac magnetic resonance, and echocardiography. This bird's eye view will inform readers about multiple studies from these different modalities. We hope that this general overview will be useful for those that did not attend the conference as well as to those that did since it is often difficult to get exposure to many abstracts at large meetings. The review, therefore, aims to help readers stay updated on the newest imaging studies presented at the meeting.

Enhancing contrast agents and radiotracers performance through hyaluronic acid-coating in neuroradiology and nuclear medicine.

The use of hyaluronic acid nanoshells has been proposed to encapsulate prodrugs and exploit the mechanisms of interactions between living cells, like endocytes or cancer cells and hyaluronic acid, which is a natural component of the extracellular matrix. In this review we describe the potential and the limits of this promising research trend and discuss the theoretical advantages of such an engineering approach. Is it a possible scalability to increase the efficacy and biodegradability of molecules like contrast media and radiotracers especially for neuroradiology and nuclear medicine studies.

Multimodality-multiparametric brain tumors evaluation.

Brain tumors represent a vast group of lesions, originating from different neuronal cells with different degrees of aggressiveness. Despite some technological advances either pre or post-treatment, these tumors may share similar imaging findings and properties, rendering diagnosis/prognosis, an ambiguous process. Gadolinium-enhanced magnetic resonance imaging remains the gold standard for providing detailed morphologic information, but presents several limitations due to the overlap of findings, in cases such as progressive tumor and post-radiation related effects. Tumor cellularity, vascularity, proliferative activity, metabolic and functional profiles are a few of many characteristics that may further support tumor classification, but cannot be assessed by conventional imaging alone. We review the aforementioned factors and indicate how they improve tumor characterization and grading in order to design the optimal treatment strategy and better evaluate post treatment efficacy.

Is there still a role for computed tomography and bone scintigraphy in prostate cancer staging? An analysis from the EUREKA-1 database.

PURPOSE: According to the current guidelines, computed tomography (CT) and bone scintigraphy (BS) are optional in intermediate-risk and recommended in high-risk prostate cancer (PCa). We wonder whether it is time for these examinations to be dismissed, evaluating their staging accuracy in a large cohort of radical prostatectomy (RP) patients. METHODS: To evaluate the ability of CT to predict lymph node involvement (LNI), we included 1091 patients treated with RP and pelvic lymph node dissection, previously staged with abdomino-pelvic CT. As for bone metastases, we included 1145 PCa patients deemed fit for surgery, previously staged with Tc-99m methylene diphosphonate planar BS. RESULTS: CT scan showed a sensitivity and specificity in predicting LNI of 8.8 and 98 %; subgroup analysis disclosed a significant association only for the high-risk subgroup of 334 patients (P 0.009) with a sensitivity of 11.8 % and positive predictive value (PPV) of 44.4 %. However, logistic multivariate regression analysis including preoperative risk factors excluded any additional predictive ability of CT even in the high-risk group (P 0.40). These data are confirmed by ROC curve analysis, showing a low AUC of 54 % for CT, compared with 69 % for Partin tables and 80 % for Briganti nomogram. BS showed some positivity in 74 cases, only four of whom progressed, while 49 patients with negative BS progressed during their follow-up, six of them immediately after surgery. CONCLUSIONS: According to our opinion, the role of CT and BS should be restricted to selected high-risk patients, while clinical predictive nomograms should be adopted for the surgical planning.

The role and clinical effectiveness of multimodality imaging in the management of cardiac complications of cancer and cancer therapy.

With the increasing number of individuals living with a current or prior diagnosis of cancer, it is important for the cardiovascular specialist to recognize the various complications of cancer and its therapy on the cardiovascular system. This is true not only for established cancer therapies, such as anthracyclines, that have well established cardiovascular toxicities, but also for the new targeted therapies that can have "off target" effects in the heart and vessels. The purpose of this informational statement is to provide cardiologists, cardiac imaging specialists, cardio-oncologists, and oncologists an understanding of how multimodality imaging may be used in the diagnosis and management of the cardiovascular complications of cancer therapy. In addition, this document is meant to provide useful general information concerning the cardiovascular complications of cancer and cancer therapy as well as established recommendations for the monitoring of specific cardiotoxic therapies.

The role of nuclear cardiac imaging in risk stratification of sudden cardiac death.

Sudden cardiac death (SCD) represents a significant portion of all cardiac deaths. Current guidelines focus mainly on left ventricular ejection fraction (LVEF) as the main criterion for SCD risk stratification and management. However, LVEF alone lacks both sensitivity and specificity in stratifying patients. Recent research has provided interesting data which supports a greater role for advanced cardiac imaging in risk stratification and patient management. In this article, we will focus on nuclear cardiac imaging, including left ventricular function assessment, myocardial perfusion imaging, myocardial blood flow quantification, metabolic imaging, and neurohormonal imaging. We will discuss how these can be used to better understand SCD and better stratify patient with both ischemic and non-ischemic cardiomyopathy.

Endogenous Technology Adoption and Medical Costs.

Despite the claim that technology has been one of the most important drivers of healthcare spending growth over the past decades, technology variables are rarely introduced explicitly in cost equations. Furthermore, technology is often considered exogenous. Using 1996-2007 panel data on Swiss geographical areas, we assessed the impact of technology availability on per capita healthcare spending covered by basic health insurance whilst controlling for the endogeneity of health technology availability variables. Our results suggest that medical research, patent intensity and the density of employees working in the medical device industry are influential factors for the adoption of technology and can be used as instruments for technology availability variables in the cost equation. These results are similar to previous findings: CT and PET scanner adoption is associated with increased healthcare spending, whilst increased availability of percutaneous transluminal coronary angioplasty facilities is associated with reductions in per capita spending. However, our results suggest that the magnitude of these relationships is much greater in absolute value than that suggested by previous studies that did not control for the possible endogeneity of the availability of technologies. Copyright © 2016 John Wiley & Sons, Ltd.

Isotopic Scintigraphy Coupled With Computed Tomography for the Investigation of Intrathecal Baclofen Device Malfunction.

OBJECTIVE: To assess the potential use of indium-111 diethylenetriamine pentaacetic acid ((111)In-DTPA) scintigraphy coupled with computed tomography (CT) for the investigation of intrathecal baclofen (ITB) device malfunction. DESIGN: Retrospective study of a case series of patients. SETTING: Neurosurgical and physical and rehabilitation medicine departments. PARTICIPANTS: Patients (N=7) with reduced ITB effectiveness in whom prior conventional radiographs were inconclusive. INTERVENTION: Nine (111)In-DTPA scintigraphic studies and 8 CT scans. Planar acquisitions were followed by tomoscintigraphy combined with CT. MAIN OUTCOME MEASURE: Progression of the radiotracer in the pump, catheters, and in the subarachnoid space. RESULTS: In 7 cases, scintigraphy coupled with CT showed leakage behind the pump, lack of activity outside the pump reservoir, abrupt interruption of activity in the catheter, or abnormal distribution of the radiotracer, thus demonstrating that the drug did not reach its target. Surgical revision confirmed these findings in 5 cases. In 1 case, combined imagery ruled out device dysfunction. In the remaining case, only planar acquisitions were performed, showing correct diffusion of the radiotracer. CONCLUSIONS: The combination of scintigraphy and CT provides simultaneous functional and anatomic imagery of the device. The slow infusion of the radioisotope mimics the diffusion of baclofen, and this could be a useful method to explore intrathecal device malfunction. Further studies are required to compare scintigraphy coupled with CT, to radiopaque injection followed by fluoroscopy or CT.

[Hemato-oncological imaging : Importance of hybrid procedures]. / Hämatoonkologische Bildgebung : Stellenwert der Hybridverfahren.

CLINICAL/METHODICAL ISSUE: Biomedical imaging procedures play a major role in hemato-oncological diseases with respect to pre-therapeutic staging and assessment of treatment response. STANDARD RADIOLOGICAL METHODS: Originally, the therapeutic management was the domain of computed tomography (CT) and whole-body magnetic resonance imaging (MRI). METHODICAL INNOVATIONS: Over the last decade these purely morphological techniques have gradually been replaced by hybrid imaging techniques, such as positron emission tomography-CT (PET/CT) and PET/MRI, which also provide metabolic and functional information. PERFORMANCE: For lymphomas, the PET tracer 18F-fluorodeoxyglucose (18 F-FDG) is meanwhile so well-established that its use is a cornerstone of the Lugano classification; however, for multiple myeloma the search for an optimal PET tracer that can also detect early disease stages is still ongoing. Functional MRI techniques, such as diffusion-weighted imaging (DWI), perfusion-weighted imaging and dynamic contrast-enhanced imaging have shown promising results for both lymphomas and multiple myelomas. ACHIEVEMENTS: The PET/MRI technique can combine the different types of information due to its truly multiparametric approach. PRACTICAL RECOMMENDATIONS: In the future PET/MRI could possibly become the hybrid imaging technique of choice for hemato-oncological diseases.

[Molecular imaging in neurological diseases]. / Molekulare Bildgebung bei neurologischen Erkrankungen.

In neurodegeneration and in neuro-oncology, the standard imaging procedure, magnetic resonance imaging (MRI), shows limited sensitivity and specificity. Molecular imaging with specific positron-emission tomography (PET) and single-photon emission computed tomography (SPECT) tracers allows various molecular targets and metabolic processes to be assessed and is thus a valuable adjunct to MRI. Two important examples are referred to here: amino acid transport for neuro-oncological issues, and the recently approved PET tracers for detecting amyloid depositions during the preclinical stage of Alzheimer's disease. This review discusses the clinical relevance and indications for the following nuclear medicine imaging procedures: amyloid PET, (18)F-fluorodeoxyglucose (FDG)-PET, and dopamine transporter (DaT)-SPECT for the diagnosis of dementia and the differential diagnosis of Parkinson's disease, in addition to amino acid PET for the diagnosis of brain tumors and somatostatin receptor imaging in meningioma.

[Degenerative cerebellar diseases and differential diagnoses]. / Degenerative Kleinhirnerkrankungen und Differenzialdiagnosen.

CLINICAL/METHODICAL ISSUE: Cerebellar syndromes result in distinct clinical symptoms, such as ataxia, dysarthria, dysmetria, intention tremor and eye movement disorders. STANDARD RADIOLOGICAL METHODS: In addition to the medical history and clinical examination, imaging is particularly important to differentiate other diseases, such as hydrocephalus and multi-infarct dementia from degenerative cerebellar diseases. Degenerative diseases with cerebellar involvement include Parkinson's disease, multiple system atrophy as well as other diseases including spinocerebellar ataxia. ACHIEVEMENTS: In addition to magnetic resonance imaging (MRI), nuclear medicine imaging investigations are also helpful for the differentiation. PRACTICAL RECOMMENDATIONS: Axial fluid-attenuated inversion recovery (FLAIR) and T2-weighted sequences can sometimes show a signal increase in the pons as a sign of degeneration of pontine neurons and transverse fibers in the basilar part of the pons. The imaging is particularly necessary to exclude other diseases, such as normal pressure hydrocephalus (NPH), multi-infarct dementia and cerebellar lesions.

Radiological prognostication in patients with head trauma requiring decompressive craniectomy: Analysis of optic nerve sheath diameter and Rotterdam CT Scoring System.

INTRODUCTION: Optic nerve sheath diameter (ONSD) measured on CT scan has been shown to predict outcomes of patients with severe traumatic brain injury. No such relation has been studied in patients undergoing decompressive craniectomy (DC). We evaluated ONSD on admission CT scan to predict outcomes of patients undergoing DC along with Rotterdam CT Score (RCTS). MATERIALS AND METHODS: This retrospective cohort study was approved by the institutional ethics committee. All the consecutive patients undergoing DC with available images and records were included. We measured ONSD 3mm behind the eyeball and calculated RCTS. Glasgow Outcome Scale (GOS) was measured at last follow-up. We analyzed the data on SPSS v 19. Receiver operator curve analysis (ROC) was done to measure the predictive values of ONSD and RCTS for mortality and unfavorable outcomes. RESULTS: One hundred and seventeen patients were included. Twenty patients had bilateral DC. Mean GCS at presentation was 8.5±3.5. Mean follow-up was 7.5±1.2 months. Thirty-day mortality was 19%. Mean ONSD of both eyes was 6.73±0.89mm. Area under the curve (AUC) for bilateral mean ONSD as predictor of mortality was 0.49 [95%CI: 0.36-0.62]. AUC for RCTS was as a predictor of 30-day mortality was significant, i.e. 0.67 [95%CI: 0.572-0.820]. The difference of mean ONSD was also not significantly different between survivor and non-survivors. CONCLUSION: Admission ONSD in DC patients is high but does not predict mortality and unfavorable outcomes. RCTS has a better prognostic value for predicting mortality and unfavorable outcomes in DC patients.

Functional MRI and CT biomarkers in oncology.

Imaging biomarkers derived from MRI or CT describe functional properties of tumours and normal tissues. They are finding increasing numbers of applications in diagnosis, monitoring of response to treatment and assessment of progression or recurrence. Imaging biomarkers also provide scope for assessment of heterogeneity within and between lesions. A wide variety of functional parameters have been investigated for use as biomarkers in oncology. Some imaging techniques are used routinely in clinical applications while others are currently restricted to clinical trials or preclinical studies. Apparent diffusion coefficient, magnetization transfer ratio and native T1 relaxation time provide information about structure and organization of tissues. Vascular properties may be described using parameters derived from dynamic contrast-enhanced MRI, dynamic contrast-enhanced CT, transverse relaxation rate (R2*), vessel size index and relative blood volume, while magnetic resonance spectroscopy may be used to probe the metabolic profile of tumours. This review describes the mechanisms of contrast underpinning each technique and the technical requirements for robust and reproducible imaging. The current status of each biomarker is described in terms of its validation, qualification and clinical applications, followed by a discussion of the current limitations and future perspectives.