Endovascular Treatment of Traumatic Vascular Injuries in the Head and Neck Region.

Background and Objectives: Traumatic vascular injuries of the head and neck pose significant treatment challenges due to the complex anatomy, diverse clinical presentation, and mostly emergent nature. Endovascular treatment increasingly complements traditional surgical approaches. This study aimed to report our 10-year experience in treating traumatic vascular injuries of the head and neck with endovascular therapy and to determine the effectiveness of endovascular treatment. Materials and Methods: A retrospective analysis of 21 patients treated for head and neck vascular injuries between May 2011 and April 2021 was performed. Patients' medical histories, clinical presentations, imaging findings, treatment materials, and clinical outcomes were reviewed. Treatments included stenting, coil embolization, and other endovascular techniques focused on hemostasis and preservation of the parent vessel. Results: The most common injuries involved the internal maxillary artery branches (n = 11), followed by the common or internal carotid artery (n = 6), vertebral artery (n = 3), and others. Endovascular treatment achieved successful hemostasis in all but one case. In five of six carotid artery injuries and two of three vertebral artery injuries, we achieved successful hemostasis while preserving the parent vessel using covered and bare stents, respectively. Conclusions: Endovascular therapy might be a useful treatment modality for traumatic vascular injuries in the head and neck region, offering efficacy, safety, and a minimally invasive approach.

False-positive supraclavicular lymph node detected on chest computed tomography in oncology patients: Clinical implication based on subsequent neck ultrasonography and ultrasonography-guided tissue sampling.

PURPOSE: The purpose of this study was to assess the prevalence and clinical implications of false-positive supraclavicular lymph node (LN) detected on chest computed tomography (CT), using subsequent neck ultrasonography (US) and US-guided tissue sampling. METHODS: Among 172 patients with suspected supraclavicular LNs identified on CT, 87 underwent neck US or US-guided tissue sampling. Receiver operating characteristic curve and logistic regression analyses were performed to determine the diagnostic performance of US and independent predictors of false-positive LNs. RESULTS: Among 87 patients, 49 (56.3%) were pathologically confirmed as metastases, 26 (29.9%) were negative for malignancy, and 12 (13.8%) had pseudolesions or schwannomas. The diagnostic indices were as follows: sensitivity, 91.8%; specificity, 92.3%; PPV, 95.7%; NPV, 85.7%; and accuracy, 92.0% (AUC = 0.921; 95% CI: 0.832-0.970, p < 0.001). The false-positive group had a higher mean age than the true-positive group (mean age, 69.8 ± 9.2 vs. 63.9 ± 9.8, p = 0.003). Logistic regression analyses revealed that age ≥ 65 years was the only independent predictor of false-positive LNs (OR = 4.391; 95% CI: 1.037-18.582; p = 0.044). CONCLUSION: Subsequent US can be helpful for evaluating suspicious supraclavicular LNs detected on CT to establish appropriate management, especially in older patients.

Korea Seroprevalence Study of Monitoring of SARS-COV-2 Antibody Retention and Transmission (K-SEROSMART): findings from national representative sample.

OBJECTIVES: We estimated the population prevalence of antibodies to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), including unreported infections, through a Korea Seroprevalence Study of Monitoring of SARS-CoV-2 Antibody Retention and Transmission (K-SEROSMART) in 258 communities throughout Korea. METHODS: In August 2022, a survey was conducted among 10,000 household members aged 5 years and older, in households selected through two stage probability random sampling. During face-to-face household interviews, participants self-reported their health status, COVID-19 diagnosis and vaccination history, and general characteristics. Subsequently, participants visited a community health center or medical clinic for blood sampling. Blood samples were analyzed for the presence of antibodies to spike proteins (anti-S) and antibodies to nucleocapsid proteins (anti-N) SARS-CoV-2 proteins using an electrochemiluminescence immunoassay. To estimate the population prevalence, the PROC SURVEYMEANS statistical procedure was employed, with weighting to reflect demographic data from July 2022. RESULTS: In total, 9,945 individuals from 5,041 households were surveyed across 258 communities, representing all basic local governments in Korea. The overall population-adjusted prevalence rates of anti-S and anti-N were 97.6% and 57.1%, respectively. Since the Korea Disease Control and Prevention Agency has reported a cumulative incidence of confirmed cases of 37.8% through July 31, 2022, the proportion of unreported infections among all COVID-19 infection was suggested to be 33.9%. CONCLUSIONS: The K-SEROSMART represents the first nationwide, community-based seroepidemiologic survey of COVID-19, confirming that most individuals possess antibodies to SARS-CoV-2 and that a significant number of unreported cases existed. Furthermore, this study lays the foundation for a surveillance system to continuously monitor transmission at the community level and the response to COVID-19.

3D Synthetic Brain MRI with Compressed Sensing: Can It Be a Promising Way Forward for Daily Neuroimaging?

BACKGROUND: Synthetic MRI can provide multiple contrast-weighted brain images with high resolution from a single scan via a 3D sequence using an interleaved Look-Locker acquisition sequence with a T2 preparation pulse (3D-QALAS). OBJECTIVE: This study aimed to assess the diagnostic image quality of 3D synthetic MRI using compressed sensing (CS) in clinical practice. METHODS: We retrospectively reviewed the imaging data of 47 patients who underwent brain MRI, including 3D synthetic MRI using CS in a single session, between December 2020 and February 2021. Two neuroradiologists independently evaluated the overall image quality, anatomic demarcation, and artifacts for synthetic 3D T1-weighted, T2-weighted, FLAIR, phase-sensitive inversion recovery (PSIR), and double inversion recovery images, using a 5-point Likert scale. The interobserver agreement between the two readers was assessed using percent agreement and weighted κ statistics. RESULTS: The overall image quality of 3D synthetic T1WI and PSIR was good to excellent, with easy or excellent anatomic demarcation and mild or no visible artifact. However, other 3D synthetic MRI-derived images showed insufficient image quality and anatomic demarcation with marked CSF pulsation artifacts. In particular, 3D synthetic FLAIR showed high-signal artifacts on the brain surface. CONCLUSION: 3D synthetic MRI, at its current status, cannot completely replace conventional brain MRI in daily clinical practice. However, 3D synthetic MRI can achieve scan-time reduction using CS and parallel imaging and may be useful for motion-prone or pediatric patients requiring 3D images where time-efficiency is important.

Prevalence and Clinical Implications of Incidental Aortic Arch Abnormalities on Contrast-Enhanced Neck MR Angiography: A Single-Center Experience.

Background and Objectives: Vascular abnormalities within the anatomical coverage are frequently encountered in imaging studies. The aortic arch is often overlooked as an anatomical blind spot, especially in neck magnetic resonance (MR) angiography. This study investigated the prevalence of incidental aortic arch abnormalities. We also estimated the potential clinical significance of aortic arch abnormalities as blind spots detected on contrast-enhanced neck MR angiography. Materials and Methods: Between February 2016 and March 2023, 348 patients were identified based on contrast-enhanced neck MR angiography reports. The clinical and radiological characteristics of the patients and the presence of additional imaging studies were assessed. The aortic arch abnormalities and coexisting non-aortic arterial abnormalities were classified into two categories according to their clinical significance. We performed the χ2 test and Fisher's exact test for group comparisons. Results: Of the 348 study patients, only 29 (8.3%) had clinically significant incidental aortic arch abnormalities. Among these 348 patients, 250 (71.8%) and 136 (39%) had intracranial and extracranial abnormalities, respectively; the clinically significant intracranial abnormalities in the two groups were 130 lesions (52.0%) and 38 lesions (27.9%), respectively. In addition, there was a significantly higher tendency of clinically significant aortic arch abnormalities (13/29, 44.8%) in the patients who had clinically significant coexisting non-aortic arterial abnormalities than in the other group (87/319, 27.3%) (p = 0.044). The patient groups with clinically significant intracranial or extracranial arterial abnormalities had higher rates of clinically significant aortic abnormalities (31.0% and 17.2%), but there was no statistical significance (p = 0.136). Conclusions: The incidence of clinically significant aortic arch abnormalities was 8.3% on neck MR angiography, with a significant association between aortic and coexisting non-aortic arterial abnormalities. The findings of this study could improve the understanding of incidental aortic arch lesions on neck MR angiography, which is of crucial clinical importance for radiologists to achieve accurate diagnoses and management.

Kikuchi-Fujimoto Disease in the Axilla after COVID-19 Vaccination: A Case Report.

BACKGROUND: Kikuchi-Fujimoto disease (KFD) is a rare, self-limiting inflammatory condition of unknown etiology that is characterized by fever and painful lymphadenopathy. KFD commonly involves the posterior cervical region and very rarely occurs in the axilla. CASE PRESENTATION: We report on a case of KFD that presented 3 weeks after receiving the messenger ribonucleic acid-based coronavirus disease 2019 (COVID-19) vaccine. In this case, we suspected the lesions as COVID-19 vaccination-related lymphadenopathy on the initial ultrasonographic examination. CONCLUSION: Through this case report, we highlight that KFD should be considered in the differential diagnosis of patients with axillary lymphadenopathy who have undergone COVID-19 vaccination, as unusual side effects of COVID-19 vaccination have been increasingly reported in the literature owing to the rapid development of various COVID-19 vaccines during the pandemic period. In addition, we emphasize the importance of clinical suspicion in diagnosing KFD due to the fact that axillary involvement of KFD is extremely rare.

Generative adversarial network with radiomic feature reproducibility analysis for computed tomography denoising.

BACKGROUND: Most computed tomography (CT) denoising algorithms have been evaluated using image quality analysis (IQA) methods developed for natural image, which do not adequately capture the texture details in medical imaging. Radiomics is an emerging image analysis technique that extracts texture information to provide a more objective basis for medical imaging diagnostics, overcoming the subjective nature of traditional methods. By utilizing the difficulty of reproducing radiomics features under different imaging protocols, we can more accurately evaluate the performance of CT denoising algorithms. METHOD: We introduced radiomic feature reproducibility analysis as an evaluation metric for a denoising algorithm. Also, we proposed a low-dose CT denoising method based on a generative adversarial network (GAN), which outperformed well-known CT denoising methods. RESULTS: Although the proposed model produced excellent results visually, the traditional image assessment metrics such as peak signal-to-noise ratio and structural similarity failed to show distinctive performance differences between the proposed method and the conventional ones. However, radiomic feature reproducibility analysis provided a distinctive assessment of the CT denoising performance. Furthermore, radiomic feature reproducibility analysis allowed fine-tuning of the hyper-parameters of the GAN. CONCLUSION: We demonstrated that the well-tuned GAN architecture outperforms the well-known CT denoising methods. Our study is the first to introduce radiomics reproducibility analysis as an evaluation metric for CT denoising. We look forward that the study may bridge the gap between traditional objective and subjective evaluations in the clinical medical imaging field.

Diffuse Large B-cell Lymphoma Presenting as an "Oops" Lesion in the Nasolabial Fold: A Case Report.

BACKGROUND: Diffuse large B-cell lymphomas are the most common type of non-Hodgkin lymphoma. Because cutaneous lymphomas predominantly originate from the T cells, primary cutaneous diffuse large B-cell lymphomas are considered a rare subtype of extranodal diffuse large B-cell lymphomas that commonly involve the subcutaneous tissues of the trunk and extremities. To date, only a single case of facial primary cutaneous diffuse large B-cell lymphoma has been reported in the literature. CASE REPORT: We present a case of primary cutaneous diffuse large B-cell lymphoma presented with a small painless nodule in the right nasolabial fold that had persisted for 10 days in a 67-year-old man. Ultrasonographic findings of this lesion mimicked the features of a complicated epidermal inclusion cyst. Primary cutaneous diffuse large B-cell lymphoma was confirmed by an excisional biopsy of the mass. CONCLUSION: The diagnosis of primary cutaneous diffuse large B-cell lymphomas presenting as "oops lesions" in daily clinical practice can be challenging due to their rarity and nonspecific clinical and radiological findings. Therefore, clinical suspicion and awareness are critical for the accurate diagnosis and management of patients with palpable soft tissue masses in the head and neck region.

A Case Report of Primary Extranodal Diffuse Large B-Cell Lymphoma Involving the Masseter Muscle: Histological-Radiological Correlation.

INTRODUCTION: Diffuse large B-cell lymphoma (DLBCL) is the most common type of non- Hodgkin's lymphoma (NHL). However, the primary skeletal muscle involvement of DLBCL is extremely rare, comprising less than 1% of all the extranodal lymphoma. To date, only 8 cases of extranodal NHL involving the masticator muscles have been reported in the literature. CASE PRESENTATION: A 70-year-old male presented with a rapid progression of painless facial swelling in the left cheek. CT, MRI and US findings demonstrated a well-defined, soft tissue mass in the left masseter muscle. The histopathological diagnosis was DLBCL by US-guided core needle biopsy. The patient received three cycles of chemotherapy. CONCLUSION: Because of its rarity, primary muscular DLBCL must be considered in differential diagnosis with all possible causes of intramuscular masses. Even the integration of multiple imaging methods does not lead to a definitive diagnosis, the biopsy is the only possibility for an early diagnosis. Therefore, clinical awareness and high suspicion of this disease are important for early diagnosis and proper treatment.

Effectiveness of ultrasound-guided percutaneous transhepatic biliary drainage to reduce radiation exposure: A single-center experience.

Percutaneous transhepatic biliary drainage (PTBD) has been an effective treatment to access the biliary tree, especially in case of endoscopically inaccessible biliary tree. In general, PTBD techniques are divided into two methods: fluoroscopy-guided PTBD and ultrasound (US)-guided PTBD. This study aimed to evaluate the effectiveness of US-guided PTBD, focusing on radiation exposure according to intrahepatic duct (IHD) dilatation degree, differences between right- and left-sided approaches and differences between benign and malignant biliary stenosis/obstruction. We evaluated technical success, clinical success, procedural data (the number of liver capsule punctures, procedural time, fluoroscopy time and radiation dose), and procedure-related complications. During the study period, a total of 123 patients with biliary stenosis/obstruction or bile leakage were initially eligible. We excluded 76 patients treated with only ERCP or initially treated with ERCP followed underwent PTBD insertion. Finally, a total of 50 procedures were performed in 47 patients. Of the 47 patients, 8 patients had anatomical alteration due to previous surgery, 6 patients refused ERCP, and 3 patients failed ERCP. For the remaining 30 patients, PTBD was performed on weekend or at night, 11 of whom had poor general condition, 10 patients underwent ERCP 3 to 4 days later after PTBD insertion, 6 patients improved after PTBD insertion without ERCP, 1 patient died, and 1 patient was referred to other hospital. Remaining 1 patient underwent surgery due to Mirizzi syndrome. All procedures were performed by two interventional radiologists. Technical success rate was 100%, clinical success was 94%, and the complication rate was 10%. Fluoroscopy time and the reported radiation dose were significantly lower in patients with dilated bile ducts than in those with non-dilated bile ducts, when biliary puncture under US guidance was performed initially. However, even in patients with non-dilated bile ducts undergoing initial trials of biliary puncture under US guidance, the fluoroscopy time and the reported radiation dose were low, based on current studies. No statistical significant differences were observed in terms of technical and dosimetry results according to right-sided and left-sided procedures and benign and malignant biliary stenosis/obstruction. Thus, US-guided PTBD was found to be a safe and effective technique that significantly reduced fluoroscopy time and radiation doses.

Clinical experience of tensor-valued diffusion encoding for microstructure imaging by diffusional variance decomposition in patients with breast cancer.

Background: Diffusion-weighted imaging plays a key role in magnetic resonance imaging (MRI) of breast tumors. However, it remains unclear how to interpret single diffusion encoding with respect to its link with tissue microstructure. The purpose of this retrospective cross-sectional study was to use tensor-valued diffusion encoding to investigate the underlying microstructure of invasive ductal carcinoma (IDC) and evaluate its potential value in a clinical setting. Methods: We retrospectively reviewed biopsy-proven breast cancer patients who underwent preoperative breast MRI examination from July 2020 to March 2021. We reviewed the MRI of 29 patients with 30 IDCs, including analysis by diffusional variance decomposition enabled by tensor-valued diffusion encoding. The diffusion parameters of mean diffusivity (MD), total mean kurtosis (MKT), anisotropic mean kurtosis (MKA), isotropic mean kurtosis (MKI), macroscopic fractional anisotropy (FA), and microscopic fractional anisotropy (µFA) were estimated. The parameter differences were compared between IDC and normal fibroglandular breast tissue (FGBT), as well as the association between the diffusion parameters and histopathologic items. Results: The mean value of MD in IDCs was significantly lower than that of normal FGBT (1.07±0.27 vs. 1.34±0.29, P<0.001); however, MKT, MKA, MKI, FA, and µFA were significantly higher (P<0.005). Among all the diffusion parameters, MKI was positively correlated with the tumor size on both MRI and pathological specimen (rs=0.38, P<0.05 vs. rs=0.54, P<0.01), whereas MKT had a positive correlation with the tumor size in the pathological specimen only (rs=0.47, P<0.02). In addition, the lymph node (LN) metastasis group had significantly higher MKT, MKA, and µFA compared to the metastasis negative group (P<0.05). Conclusions: Tensor-valued diffusion encoding enables a useful non-invasive method for characterizing breast cancers with information on tissue microstructures. Particularly, µFA could be a potential imaging biomarker for evaluating breast cancers prior to surgery or chemotherapy.

Cavernous Hemangioma of the Maxillary Sinus Masquerading Recurrent Hemorrhagic Mass: Histological-Radiological Correlation and a Literature Review.

BACKGROUND: Sinonasal cavernous hemangioma is rare. To date, fewer than 20 cases have been reported in the literature; however, they may be a source of recurrent epistaxis and masquerade of a hemorrhagic mass on CT and MRI. CASE REPORT: A 68-year-old woman was presented with recurrent epistaxis and progressive right malar fullness. On rhinoscopy, a bulge lesion was observed with multifocal hemorrhagic and friable surfaces in the right nasal cavity. CT and MRI demonstrated a well-defined mass in the right maxillary sinus with inhomogenous T2 hyperintensity, hypointense septa, peripheral rim, and multiple papillary enhancement, suggesting a recurrent hemorrhagic mass. The mass was excised endoscopically, and the histologic diagnosis was cavernous hemangioma. CONCLUSION: Imaging studies, such as CT and MRI, are essential in making an accurate diagnosis of cavernous hemangioma of the maxillary sinus. Endoscopic excision of the lesion can be curative.

Automated Brain Volumetry in Patients With Memory Impairment: Comparison of Conventional and Ultrafast 3D T1-Weighted MRI Sequences Using Two Software Packages.

BACKGROUND. Isotropic 3D T1-weighted imaging has long acquisition times, potentially leading to motion artifact and altered brain volume measurements. Acquisition times may be greatly shortened using an isotropic ultrafast 3D echo-planar imaging (EPI) T1-weighted sequence. OBJECTIVE. The purpose of this article was to compare automated brain volume measurements between conventional 3D T1-weighted imaging and ultrafast 3D EPI T1-weighted imaging. METHODS. This retrospective study included 36 patients (25 women, 11 men; mean age, 68.4 years) with memory impairment who underwent 3-T brain MRI. Examinations included both conventional 3D T1-weighted imaging using inversion recovery gradient-recalled echo sequence (section thickness, 1.0 mm; acquisition time, 3 minutes 4 seconds) and, in patients exhibiting motion, an isotropic ultrafast 3D EPI T1-weighted sequence (section thickness, 1.2 mm; acquisition time, 30 seconds). The 36-patient sample excluded five patients in whom severe motion artifact rendered the conventional sequence of insufficient quality for volume measurements. Automated brain volumetry was performed using NeuroQuant (version 3.0, CorTechs Laboratories) and FreeSurfer (version 7.1.1, Harvard University) software. Volume measurements were compared between sequences for nine regions in each hemisphere. RESULTS. Volumes showed substantial to almost perfect agreement between the two sequences for most regions bilaterally. However, most regions showed significant mean differences between sequences, and Bland-Altman analyses showed consistent systematic biases and wide limits of agreement (LOA). For example, for the left hemisphere using NeuroQuant, volume was significantly greater for the ultrafast sequence in four regions and significantly greater for the conventional sequence in three regions, whereas standardized effect size between sequences was moderate for four regions and large for one region. Using NeuroQuant, mean bias (ultrafast minus conventional) and 95% LOA were greatest in cortical gray matter bilaterally (-50.61 cm3 [-56.27 cm3, -44.94 cm3] for the left hemisphere; -50.02 cm3 [-54.88 cm3, -45.16 cm3] for the right hemisphere). The variation between the two sequences was observed in subset analyses of 16 patients with and 20 patients without Alzheimer disease. CONCLUSION. Brain volume measurements show significant differences and systematic biases between the conventional and ultrafast sequences. CLINICAL IMPACT. In patients in whom severe motion artifact precludes use of the conventional sequence, the ultrafast sequence may be useful to enable brain volume-try. However, the current conventional 3D T1-weighted sequence remains preferred in patients who can tolerate the standard examination.

Large gastroduodenal artery pseudoaneurysm, arterioportal fistula and portal vein stenosis in chronic pancreatitis treated using combined transarterial embolization and transportal stenting: A case report.

RATIONALE: Chronic pancreatitis is an ongoing fibroinflammatory disease of the pancreas characterized by irreversible damage to the pancreatic parenchyma and ductal system. Besides, chronic pancreatitis can present with a variety of life-threatening complications. PATIENT CONCERNS: The patients visited our hospital due to abdominal pain and anemia, and had chronic pancreatitis as an underlying disease. DIAGNOSES: Computed tomography showed a large gastroduodenal artery pseudoaneurysm, arterioportal vein fistula, and portal vein stenosis. INTERVENTIONS: We would like to report the successful use of the coils, and N-butyl cyanoacrylate glue for the therapeutic embolization of the pseudoaneurysm and fistula between the gastroduodenal artery and the portal vein, and stenting for portal vein stenosis. OUTCOMES: On the day following the endovascular management, the patient reported remission of abdominal pain, and hemoglobin level returned to normal after transfusion. It was confirmed that it was still well maintained in the follow-up examination after 1 month. LESSONS: Although chronic pancreatitis causes many vascular complications, simultaneous occurrence of these lesions is extremely rare. Herein, we share our experience with a unique case of an extrahepatic arterioportal fistula induced by the rupture of gastroduodenal artery pseudoaneurysm with concomitant portal vein stenosis. In these complex cases, combined transarterial embolization and transportal stenting can be helpful.

Intracranial Cisternal Lipoma Associated with Cerebellar Cortical Dysplasia Diagnosed Using Dixon Technique: A Case Report and a Review of Literature.

BACKGROUND: Intracranial lipomas are very rare congenital malformations. Previous studies have shown various brain anomalies related to intracranial lipomas, most of which are agenesis or dysgenesis of the adjacent structures. To the best of our knowledge, cortical dysplasia related to intracranial lipoma has yet to be reported. CASE REPORT: We present a rare case of intracranial lipoma in the quadrigeminal and superior cerebellar cisterns with combined cerebellar cortical dysplasia. A 43-year-old female underwent brain MRI to identify possible cause of headache. We made a confident diagnosis based on MR findings using Dixon technique, which is a fat-water separation method based on chemical shift. We also identified unique combined abnormalities of the right cerebellar hemisphere near the cisternal lipoma that showed an abnormal vertical orientation of the cerebellar folia and disorganized parenchymal pattern. CONCLUSION: This case exhibits the rareness of the intracranial lipoma related cerebellar cortical dysplasia by reviewing relevant literature and also highlights the usefulness of Dixon techniques in daily clinical practice.

MALT Lymphoma of the Tongue in a Patient with Sjögren's Syndrome: A Case Report and Literature Review.

Sjögren's syndrome (SS) is a systemic chronic autoimmune disorder characterized by lymphocytic infiltration of the exocrine glands, as well as oral and ocular dryness. Among the late complications, malignant lymphoma is the most serious complication of SS. The risk of lymphoma in patients with SS has been estimated to be approximately 7-19 times higher than that in a generally healthy population. Although various histologic subtypes of lymphoma can occur in patients with SS, mucosa-associated lymphoid tissue (MALT) lymphoma accounts for 48-75% of malignant lymphomas that are frequently located in the parotid gland. However, MALT lymphoma affecting the tongue in patients with SS is extremely rare. Here, we share our experience with a unique case of MALT lymphoma of the tongue, originating from the minor salivary gland tissue in a patient with SS. Through this case report, we emphasize that MALT lymphoma should be considered in the differential diagnosis of a tongue mass in patients with SS.

Prevalence and Clinical Implications of Incidentally Detected Parotid Lesions as Blind Spot on Brain MRI: A Single-Center Experience.

Background and objective: This study was conducted to assess the prevalence and clinical implications of parotid lesions detected incidentally during brain magnetic resonance imaging (MRI) examination. Materials and Methods: Between February 2016 and February 2021, we identified 86 lesions in the brain MRI reports of 84 patients that contained the words "parotid gland" or "PG". Of these, we finally included 49 lesions involving 45 patients following histopathological confirmation. Results: Based on the laboratory, radiological or histopathological findings, the prevalence of incidental parotid lesions was low (1.2%). Among the 45 study patients, 41 (91.1%) had unilateral lesions, and the majority of the lesions were located in the superficial lobe (40/49, 81.6%). The mean size of the parotid lesions was 1.3 cm ± 0.4 cm (range, 0.5 cm-2.8 cm). Of these, 46 parotid lesions (93.9%) were benign, whereas the remaining three lesions were malignant (6.1%). Conclusions: Despite the low prevalence and incidence of malignancy associated with incidental parotid lesions detected on brain MRI, the clinical implications are potentially significant. Therefore, clinical awareness and appropriate imaging work-up of these lesions are important for accurate diagnosis and timely management.

Abdominal CT in patients with arms down positioning: Effect of virtual monoenergetic reconstruction on diagnostic image quality.

PURPOSE: To evaluate effect of virtual monoenergetic reconstruction on contrast-enhanced abdominal CT obtained using a dual-layer detector CT (DLCT) in patients with arms-down positioning, in comparison with conventional 120-kVp image. METHODS: A total of 162 consecutive patients who underwent abdominal CT scans using a DLCT with arms-down positioning were retrospectively enrolled. 120-kVp image and virtual monoenergetic images (VMIs) at 40-100 keV were compared for arm-induced artifact reduction capability and image quality through objective and subjective assessments. Diagnostic performance was compared between VMI with the best quality and 120-kVp image. RESULTS: VMIs at 60-100 keV showed significantly lower (p < 0.001) artifact index than 120-kVp image. Subjective severity of arm-induced streak artifacts was significantly (p < 0.001) lower in VMIs at 70-100 keV than in 120-kVp image. CNRs measured in artifact and reference areas were superior (p < 0.05) in 40-70 keV to those in 120 kVp. Overall image quality was superior (p < 0.05) in 60-90 keV to 120 kVp. 70-keV VMI was chosen as the best image by two independent readers. In ROC analysis of lesion detection in the liver, spleen, and kidneys, the AUC was significantly higher for 70-keV VMI (reader 1, 0.962; p = 0.011; reader 2, 0.981; p = 0.012) than that for 120-kVp image (reader 1, 0.891; reader 2, 0.922). CONCLUSION: The70-keV VMI from DLCT could improve abdominal CT images by reducing streak artifacts and increasing image contrast in patients who could not elevated their arms. The 70-keV VMI showed better diagnostic performance than the conventional 120 kVp image.

BAI1 nuclear expression reflects the survival of nonsmoking non-small cell lung cancer patients.

BACKGROUND: Smoking- and nonsmoking-associated lung cancers have different mechanisms of carcinogenesis. We divided non-small cell lung cancer (NSCLC) patients into nonsmoking and smoking groups with the aim of trying to understand the utility of brain-specific angiogenesis inhibitor 1 (BAI1) expression in the separate groups. METHODS: Clinicopathological data were obtained from 148 patients who had undergone surgery for NSCLC of the lung. Tissue microarray blocks were made of samples from NSCLC patients. Two pathologists graded the intensity of BAI1 expression as high or low expression in the cancer cells of patients in the smoking and nonsmoking groups. RESULTS: NSCLC nonsmokers with higher BAI1 nuclear expression had poor disease-specific survival (DSS) (hazard ratio: 2.679; 95% confidence interval [CI]:1.022-7.022, p = 0.045). The Kaplan-Meier survival curve confirmed that higher BAI1 expression was significantly associated with poor DSS (p = 0.034) in the nonsmoking group. CONCLUSIONS: We divided NSCLC patients into nonsmoking and smoking groups and found that nuclear BAI1 expression was related to patient survival in nonsmoking NSCLC patients. We suggest BAI1 expression as a predictive marker of nonsmoking-associated NSCLC and recommend that it be evaluated as an AJCC staging criterion in the future.

Feasibility study of ultra-low-dose dedicated maxillofacial computed tomography using filter-based spectral shaping in patients with craniofacial trauma: assessment of image quality and radiation dose.

BACKGROUND: In the setting of multiple trauma, radiation exposure is considered a relevant issue because patients may require repeated imaging to evaluate injuries in different body parts. Recently, spectral shaping of the X-ray beam has been shown to be beneficial in reducing radiation exposure. We investigated the clinical feasibility of a tin-filtered 100 kV protocol for the diagnostic use, compared to routine dedicated maxillofacial CT at 120 kVp in patients with craniofacial trauma; we assessed the image quality, radiation dose, and interobserver agreement. METHODS: We retrospectively evaluated 100 consecutive patients who underwent dedicated maxillofacial CT for craniofacial trauma. Fifty patients were examined with a tin-filtered 100 kV protocol performed using a third-generation dual source CT. The other 50 patients were examined with a standard protocol on a different scanner. Two readers independently evaluated image quality subjectively and objectively, and the interobserver agreement was also assessed. CT dose index volume (CTDIvol) and dose-length product (DLP) were recorded to compare radiation exposure. A quality-control phantom was also scanned to prospectively assess the impact of tin filtration. RESULTS: All CT scans showed diagnostic image quality for evaluating craniofacial fractures. The tin-filtered 100 kV protocol showed sufficient-to-good image quality for diagnostic use; however, overall image quality and anatomic delineation from the tin-filtered 100 kV protocol were significantly lower than from the standard protocol. Interobserver agreement was moderate to almost perfect (k=0.56-0.85). Image noises in the air, eye globe, and retrobulbar fat were comparable between the two protocols (P>0.05), whereas both signal-to-noise ratio and contrast-to-noise ratio in the eye globe and retrobulbar fat showed a significant difference (P<0.05). The tin-filtered 100 kV protocol showed a significant reduction in radiation dose compared to the standard protocol: CTDIvol, 3.33 vs. 30.5 mGy (P<0.001); and DLP, 70.70 vs. 669.43 mGy*cm (P<0.001). The phantom study also demonstrated a lower radiation dose for the tin-filter 100 kV protocol compared to the standard protocol. CONCLUSIONS: Dedicated maxillofacial CT using spectral shaping with tin filtration can allow a significant reduction in radiation dose while maintaining sufficient diagnostic image quality, when compared to the standard protocol.