Temporal Bone High Resolution Computed Tomography Findings in a Case of Postpartum Otosclerosis.

We describe temporal bone high resolution computed tomography (HRCT) findings in a case of bilateral mixed fenestral and retrofenestral otosclerosis with onset in the postpartum period. This condition should be considered in women complaining of postpartum hearing loss and temporal bone HRCT is a fundamental tool leading to the diagnosis.

Overview of the Current Knowledge and Conventional MRI Characteristics of Peri- and Para-Vascular Spaces.

Brain spaces around (perivascular spaces) and alongside (paravascular or Virchow-Robin spaces) vessels have gained significant attention in recent years due to the advancements of in vivo imaging tools and to their crucial role in maintaining brain health, contributing to the anatomic foundation of the glymphatic system. In fact, it is widely accepted that peri- and para-vascular spaces function as waste clearance pathways for the brain for materials such as ß-amyloid by allowing exchange between cerebrospinal fluid and interstitial fluid. Visible brain spaces on magnetic resonance imaging are often a normal finding, but they have also been associated with a wide range of neurological and systemic conditions, suggesting their potential as early indicators of intracranial pressure and neurofluid imbalance. Nonetheless, several aspects of these spaces are still controversial. This article offers an overview of the current knowledge and magnetic resonance imaging characteristics of peri- and para-vascular spaces, which can help in daily clinical practice image description and interpretation. This paper is organized into different sections, including the microscopic anatomy of peri- and para-vascular spaces, their associations with pathological and physiological events, and their differential diagnosis.

Late/delayed gadolinium enhancement in MRI after intravenous administration of extracellular gadolinium-based contrast agents: is it worth waiting?

The acquisition of images minutes or even hours after intravenous extracellular gadolinium-based contrast agents (GBCA) administration ("Late/Delayed Gadolinium Enhancement" imaging; in this review, further termed LGE) has gained significant prominence in recent years in magnetic resonance imaging. The major limitation of LGE is the long examination time; thus, it becomes necessary to understand when it is worth waiting time after the intravenous injection of GBCA and which additional information comes from LGE. LGE can potentially be applied to various anatomical sites, such as heart, arterial vessels, lung, brain, abdomen, breast, and the musculoskeletal system, with different pathophysiological mechanisms. One of the most popular clinical applications of LGE regards the assessment of myocardial tissue thanks to its ability to highlight areas of acute myocardial damage and fibrotic tissues. Other frequently applied clinical contexts involve the study of the urinary tract with magnetic resonance urography and identifying pathological abdominal processes characterized by high fibrous stroma, such as biliary tract tumors, autoimmune pancreatitis, or intestinal fibrosis in Crohn's disease. One of the current areas of heightened research interest revolves around the possibility of non-invasively studying the dynamics of neurofluids in the brain (the glymphatic system), the disruption of which could underlie many neurological disorders.

Extrahepatic abscess and dropped gallstones: a case report and a narrative review of an unusual delayed complication of laparoscopic cholecystectomy.

BACKGROUND: Laparoscopic cholecystectomy is the most common minimally invasive abdominal surgery procedure performed in Western countries; it offers several advantages over laparotomy but still carries some risks, such as intraoperative spillage of bile and gallstones. Diagnosis of dropped gallstones could be challenging, it is frequently delayed, and this can lead to further complications such as abscesses formation. METHODS: We report the history of a 51-year-old male with persistent dull abdominal pain in association to appetite loss, vomiting episodes and changes in regular bowel habits, a past medical history of laparoscopic cholecystectomy for biliary lithiasis (1.5 years earlier) and minimum elevation of inflammatory markers and gamma-GT values. RESULTS: Ultrasound examination showed perihepatic stones and magnetic resonance imaging revealed the presence of multiple perihepatic abscesses, findings compatible with fibrotic-inflammatory phenomena from 'dropped gallstones'. A re-laparoscopy was then performed with an abscess collection containing multiple gallstones; a liver wedge resection was also required due to strong adhesions. At follow up, the patient had improved both on clinical and biochemical perspective. CONCLUSION: Dropped gallstones are an underreported cause of morbidity and diagnostic dilemmas in subjects who underwent to laparoscopic cholecystectomy, in relation to infectious complications that can occur even several months or years after surgery. Imaging represents a valuable aid in the correct non-invasive diagnostic process, but proper awareness of this insidious condition is necessary. Surgeons and radiologists should always consider this eventuality in the differential diagnosis of a patient presenting with abdominal abscesses and history of cholecystectomy.

The role of gadolinium-based contrast agents in magnetic resonance imaging structured reporting and data systems (RADS).

Among the 28 reporting and data systems (RADS) available in the literature, we identified 15 RADS that can be used in Magnetic Resonance Imaging (MRI). Performing examinations without using gadolinium-based contrast agents (GBCA) has benefits, but GBCA administration is often required to achieve an early and accurate diagnosis. The aim of the present review is to summarize the current role of GBCA in MRI RADS. This overview suggests that GBCA are today required in most of the current RADS and are expected to be used in most MRIs performed in patients with cancer. Dynamic contrast enhancement is required for correct scores calculation in PI-RADS and VI-RADS, although scientific evidence may lead in the future to avoid the GBCA administration in these two RADS. In Bone-RADS, contrast enhancement can be required to classify an aggressive lesion. In RADS scoring on whole body-MRI datasets (MET-RADS-P, MY-RADS and ONCO-RADS), in NS-RADS and in Node-RADS, GBCA administration is optional thanks to the intrinsic high contrast resolution of MRI. Future studies are needed to evaluate the impact of the high T1 relaxivity GBCA on the assignment of RADS scores.

Interrater reliability of Brain Tumor Reporting and Data System (BT-RADS) in the follow up of adult primary brain tumors: a single institution experience in Italy.

Background: In 2018, a new system was proposed for classifying and reporting post-treatment adult brain tumor on magnetic resonance imaging, named as Brain Tumor Reporting and Data System (BT-RADS), that needs a validation by means of agreement studies. Methods: A retrospective study was designed with the aim of identifying contrast-enhanced magnetic resonance imaging (MRI) of adult patients on follow-up for primary brain tumor at Fondazione Policlinico Campus Bio-Medico. Four radiologists (2 radiology residents, 1 general radiologist, 1 neuroradiologist) read and scored each study using the BT-RADS scoring tool, blinded to the MRI original report. Interobserver agreement and Fleiss' k were calculated to assess the level of diagnostic agreement. It was assessed how many times the assignment of different scoring of BT-RADS would have led to a different patient management. Results: The total number of patients included in the study was 23 with 147 MRIs and a total of 588 BT-RADS scores retrospectively evaluated. The two most frequent tumor types were astrocytoma grade 4 (62%) and oligodendroglioma grade 3 (21%). The overall agreement rate for all 4 radiologists was 82% with a Fleiss' k of 0.70. The overall agreement rate between general radiologist and neuroradiologist was 91% with a Fleiss' k of 0.86. The overall agreement rate between 2 radiology residents and neuroradiologist was 80% with a Fleiss' k of 0.66. Astrocytoma grade 3 (k: 0.51) and oligodendroglioma grade 2 (k: 0.32) showed a poor agreement while higher values of agreement were found for astrocytoma grade 4 (k: 0.70), astrocytoma grade 2 (k: 0.78) and oligodendroglioma grade 3 (k: 0.78). All the radiologists agreed on BT-RADS assignment in 70% patients, three radiologists agreed in 17% and two radiologists agree in 13%. In no cases there was a complete disagreement among the readers. In 18% of cases the discrepancy in the estimated BT-RADS would have led to a different follow-up management. Conclusions: BT-RADS can be considered a valid tool for neuroradiologists and radiologists even with little experience in the interpretation of patients' images during follow-up for adult primary brain tumors supporting standardized interpretation, reporting and clinical management.

The role of iodinated contrast media in computed tomography structured Reporting and Data Systems (RADS): a narrative review.

Background and Objective: In recent years, there has been a large-scale dissemination of guidelines in radiology in the form of Reporting & Data Systems (RADS). The use of iodinated contrast media (ICM) has a fundamental role in enhancing the diagnostic capabilities of computed tomography (CT) but poses certain risks. The scope of the present review is to summarize the current role of ICM only in clinical reporting guidelines for CT that have adopted the "RADS" approach, focusing on three specific questions per each RADS: (I) what is the scope of the scoring system; (II) how is ICM used in the scoring system; (III) what is the impact of ICM enhancement on the scoring. Methods: We analyzed the original articles for each of the latest versions of RADS that can be used in CT [PubMed articles between January, 2005 and March, 2023 in English and American College of Radiology (ACR) official website]. Key Content and Findings: We found 14 RADS suitable for use in CT out of 28 RADS described in the literature. Four RADS were validated by the ACR: Colonography-RADS (C-RADS), Liver Imaging-RADS (LI-RADS), Lung CT Screening-RADS (Lung-RADS), and Neck Imaging-RADS (NI-RADS). One RADS was validated by the ACR in collaboration with other cardiovascular scientific societies: Coronary Artery Disease-RADS 2.0 (CAD-RADS). Nine RADS were proposed by other scientific groups: Bone Tumor Imaging-RADS (BTI-RADS), Bone­RADS, Coronary Artery Calcium Data & Reporting System (CAC-DRS), Coronavirus Disease 2019 Imaging-RADS (COVID-RADS), COVID-19-RADS (CO-RADS), Interstitial Lung Fibrosis Imaging-RADS (ILF-RADS), Lung-RADS (LU-RADS), Node-RADS, and Viral Pneumonia Imaging-RADS (VP-RADS). Conclusions: This overview suggests that ICM is not strictly necessary for the study of bones and calcifications (CAC-DRS, BTI-RADS, Bone-RADS), lung parenchyma (Lung-RADS, LU-RADS, COVID-RADS, CO-RADS, VP-RADS and ILF-RADS), and in CT colonography (C-RADS). On the other hand, ICM plays a key role in CT angiography (CAD-RADS), in the study of liver parenchyma (LI-RADS), and in the evaluation of soft tissues and lymph nodes (NI-RADS, Node-RADS). Future studies are needed in order to evaluate the impact of the new iodinated and non-iodinate contrast media, artificial intelligence tools and dual energy CT in the assignment of RADS scores.

Right Condylar Jugular Diverticulum: Contrast-enhanced Computed Tomography Findings of a Rare Anatomical Variant of Jugular Bulb.

This is the first description of condylar jugular diverticulum (CJD) by means of contrast-enhanced computed tomography scan in the medical literature. CJD is a rare anatomical variant of jugular bulb that should be known to avoid radiological and surgical errors and achieve an appropriate pre-surgical planning of skull base pathologies.

Skin Toxicity After Exposure to Gadolinium-Based Contrast Agents in Normal Renal Function, Using Clinical Approved Doses: Current Status of Preclinical and Clinical Studies.

OBJECTIVES: The aim of this study was to summarize the current preclinical and clinical evidence on the association between exposure to gadolinium (Gd) compounds and skin toxicity in a setting similar to clinical practice. MATERIALS AND METHODS: A search of MEDLINE and PubMed references from January 2000 to December 2022 was performed using keywords related to gadolinium deposition and its effects on the skin, such as "gadolinium," "gadolinium-based contrast agents," "skin," "deposition," and "toxicity." In addition, cross-referencing was added when appropriate. For preclinical in vitro studies, we included all the studies that analyzed the response of human dermal fibroblasts to exposure to various gadolinium compounds. For preclinical animal studies and clinical studies, we included only those that analyzed animals or patients with preserved renal function (estimated glomerular filtration rate >30 mL/min/1.73 m 2 ), using a dosage of gadolinium-based contrast agents (GBCAs) similar to that commonly applied (0.1 mmol/kg). RESULTS: Forty studies were selected. Preclinical findings suggest that Gd compounds can produce profibrotic responses in the skin in vitro, through the activation and proliferation of dermal fibroblasts and promoting their myofibroblast differentiation. Gadolinium influences the process of collagen production and the collagen content of skin, by increasing the levels of matrix metalloproteinase-1 and tissue inhibitor of metalloproteinase-1. Preclinical animal studies show that Gd can deposit in the skin with higher concentrations when linear GBCAs are applied. However, these deposits decrease over time and are not associated with obvious macroscopic or histological modifications. The clinical relevance of GBCAs in inducing small fiber neuropathy remains to be determined. Clinical studies show that Gd is detectable in the skin and hair of subjects with normal renal function in higher concentrations after intravenous administration of linear compared with macrocyclic GBCA. However, these deposits decrease over time and are not associated with cutaneous or histological modifications. Also, subclinical dermal involvement related to linear GBCA exposure may be detectable on brain MRI. There is no conclusive evidence to support a causal relationship between GBCA administration at the clinical dose and cutaneous manifestations in patients with normal renal function. CONCLUSIONS: Gadolinium can produce profibrotic responses in the skin, especially acting on fibroblasts, as shown by preclinical in vitro studies. Gadolinium deposits are detectable in the skin even in subjects with normal renal function with higher concentrations when linear GBCAs are used, as confirmed by both preclinical animal and human studies. There is no proof to date of a cause-effect relationship between GBCA administration at clinical doses and cutaneous consequences in patients with normal renal function. Multiple factors, yet to be determined, should be considered for sporadic patients with normal renal function who develop clinical skin manifestations temporally related to GBCA administration.

Skin Thickening of the Scalp and High Signal Intensity of Dentate Nucleus in Multiple Sclerosis: Association With Linear Versus Macrocyclic Gadolinium-Based Contrast Agents Administration.

OBJECTIVE: The aim of this study was to assess the presence of detectable changes of skin thickness on clinical brain magnetic resonance imaging (MRI) scans in patients with MS, history of multiple gadolinium-based contrast agents (GBCAs) administrations, and evidence of gadolinium deposition in the brain. MATERIALS AND METHODS: In this observational cross-sectional study, 71 patients with MS who underwent conventional brain MRI with an imaging protocol including enhanced 3D volumetric interpolated breath-hold examination (VIBE) T1-weighted with fat saturation were assessed. Patients with bilateral isointense dentate nucleus on unenhanced T1-weighted images were assigned to group A (controls without MRI evidence of gadolinium deposition), and patients with visually hyperintense dentate nuclei were assigned to group B. Qualitative and quantitative assessment of the skin thickness were performed. RESULTS: Group A included 27 patients (median age, 33 years [IQR, 27-46]; 20 women), and group B included 44 patients (median age, 42 years [IQR, 35-53]; 29 women). Qualitative and quantitative assessment of the skin revealed significant differences between group A and group B. The average skin-to-scalp thickness ratios was significantly higher in group B than in group A (mean ± standard deviation = 0.52 ± 0.02 in group B vs 0.41 ± 0.02 in group A, P < 0.0001) and showed a positive correlation with the total number of enhanced MRI scans ( r = 0.39; 95% confidence interval, 0.17-0.57, P < 0.01). CONCLUSIONS: Brain MRI detects increased skin thickness of the scalp in patients with MS and dentate nucleus high signal intensity on unenhanced T1-weighted images and shows positive association with previous exposures to linear GBCAs rather than macrocyclic GBCAs.

Imaging findings in a case of leptomeningeal myelomatosis, a rare but critical central nervous system complication of multiple myeloma.

Leptomeningeal myelomatosis is a rare complication of multiple myeloma (<1% of the patients). There was an increase in the incidence of leptomeningeal myelomatosis during the last decade; the prognosis of leptomeningeal myelomatosis remains poor, (overall median survival from the time of diagnosis of 2 months). We discuss a rare case of a monoclonal gammopathy evolving into multiple myeloma and finally into a rapidly progressing leptomeningeal disease. A 76 year-old woman in hematologic follow-up for advanced stage multiple myeloma in sixth-line treatment had an episode of generalized tonic-clonic seizure with sphincter release followed by altered state of consciousness. The unenhanced head CT scan showed a mild enlargement of the ventricular system without intra-axial or extra-axial hemorrhages nor significant changes in brain parenchyma. The subsequent contrast-enhanced brain MRI revealed a widespread nodular leptomeningeal enhancement characterized by contrast-enhancement of the pia mater extended into the subarachnoid spaces of the sulci and cisterns, involving supra- and sub-tentorial regions and the statoacoustic nerve in the inner ear canal bilaterally. The fluid-attenuated inversion recovery MRI images demonstrated an abnormally elevated signal within the sulci in the parieto-occipital regions. The radiological diagnosis of leptomeningeal myelomatosis was made. The patient died 4 days after the examination. In patients with long-lasting multiple myeloma and onset of neurological signs or symptoms, a contrast-enhanced brain MRI should be performed to assess the actual burden of central nervous system involvement in leptomeningeal myelomatosis; CT may provide a clue to the diagnosis when progressive enlargement of the ventricles over time is noted.

A Rare Case of Contained Chronic Rupture of Abdominal Aortic Aneurysm Associated With Vertebral Erosion: Pre- and Post-operative Findings on Computed Tomography and a Narrative Review.

Contained chronic rupture of aortic aneurysm (CCR-AA) is a rare condition that can be associated with vertebral body erosion (VBE) and is often a diagnostic challenge; in fact, CCR-AAs are in general hemodynamically stable and the patients tend to present with a non-specific low-back pain syndrome secondary to vertebral involvement. Furthermore, the differential diagnosis of a retroperitoneal mass can be difficult on medical imaging. We discuss the case of a 79-years-old man, heavy smoker without history of cardiovascular diseases, admitted to the emergency department with signs of left lower limb ischemia. The patient was hemodynamically stable and the medical examination revealed a pulsatile abdominal mass. Doppler ultrasound showed the presence of aneurysmal dilatation of infra-renal abdominal aorta and chronic femoropopliteal occlusion on the left side. The subsequent computed tomography angiography (CTA) demonstrated a voluminous retroperitoneal mass continuous with the infra-renal aorta, which infiltrated the psoas muscles and caused vertebral bodies erosion of the anterior wall in L2, L3 and L4 suspected for CCR-AA or mycotic aortic aneurysm. Furthermore, the examination confirmed the occlusion of the peripheral arterial circulation of the left lower limb. The patient underwent a successful open replacement of the infra-renal abdominal aorta through aorto-aortic prosthetic graft insertion; the visualization during the surgical procedure of a posterior vessel wall opening in continuity with the eroded vertebral bodies associated with negative microbiological culture of the thrombotic material sample, led to the definitive diagnosis of CCR-AA. The post-operative CTA showed successful open vascular treatment. A bypass surgery of the left lower limb was then performed with positioning saphenous graft between femoral common artery and posterior tibial artery. The patient was finally discharged in good clinical conditions.

Imaging findings in a case of myo-pericarditis associated with SARS CoV-2 disease.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is known to use the host protein angiotensin-converting enzyme 2 as a co-receptor to gain intracellular entry into different organs, including the heart. Cardiac involvement is one of the clinical manifestations of coronavirus disease 2019 (COVID-19) and is associated with a worse prognosis; in this setting, few cases of myo-pericarditis with complete imaging documentation have been reported. We discuss a case of a woman admitted to the emergency department with dyspnea. Nasopharyngeal swab showed positive results for SARS-CoV-2. A subsequent 12-lead electrocardiogram showed modifications of T-wave in leads V1 to V6 while blood tests revealed increased levels of troponin I. Coronary computed tomography angiography was performed, excluding hemodynamically significant coronary stenosis. Cardiac magnetic resonance (CMR) was also performed, showing findings fulfilling Lake Louise criteria for the diagnosis of acute myo-pericarditis. To date, myocardial inflammation was recognized as connected with COVID-19 mortality. CMR is an indispensable tool for non-invasive diagnosis of this pathology; however, most clinical studies demonstrated the presence of intramyocardial edema using T1 and T2 mapping sequences. In our case, extensive intramyocardial edema was well demonstrated using TIRM sequences, with a short TI to obtain fat suppression. .

Anterior pituitary gland T1 signal intensity is influenced by time delay after injection of gadodiamide.

To test the hypothesis of washout from the anterior pituitary (AP) gland after serial injections of gadodiamide. We included 59 patients with history of at least 5 injections of gadodiamide. Values of mean signal intensity of the AP and of the central pons were measured on unenhanced sagittal T1-weighted images. AP-to-pons signal intensity ratios were calculated dividing the values of the AP by those of the pons. The measurements were performed using MR images acquired at four different time points including baseline (prior to any gadodiamide injection), minimum post-injection time delay, maximum post-injection time delay, and last available MR scans. Normalized ratios (i.e. ratios divided total volume of injected gadodiamide) were also calculated. To assess the difference between ratios, non-parametric Wilcoxon signed-rank test was applied. The correlations were tested with non-parametric Spearman correlation coefficient. A p-value < 0.05 was considered as statistically significant. A statistically significant increase of AP signal intensity was found by comparing the baseline scans with both the minimum time delay (p = 0.003) and maximum time delay scans (p = 0.005). We found significant higher normalized ratios for minimum post-injection time delay with respect to maximum post-injection time delay (p < 0.001). The normalized ratios demonstrated a statistically significant negative correlation with the post-injection time delay (r = - 0.31; p = 0.006). The findings of this study suggest that washout phenomena of retained/deposited gadolinium from the AP are influenced by the total injected volume and post-injection time delay.