Quantitative analysis of chest computed tomography of COVID-19 pneumonia using a software widely used in Japan.

This study aimed to determine the optimal conditions to measure the percentage of the area considered as pneumonia (pneumonia volume ratio [PVR]) and the computed tomography (CT) score due to coronavirus disease 2019 (COVID-19) using the Ziostation2 image analysis software (Z2; Ziosoft, Tokyo, Japan), which is popular in Japan, and to evaluate its usefulness for assessing the clinical severity. We included 53 patients (41 men and 12 women, mean age: 61.3 years) diagnosed with COVID-19 using polymerase chain reaction who had undergone chest CT and were hospitalized between January 2020 and January 2021. Based on the COVID-19 infection severity, the patients were classified as mild (n = 38) or severe (n = 15). For 10 randomly selected samples, the PVR and CT scores by Z2 under different conditions and the visual simple PVR and CT scores were compared. The conditions with the highest statistical agreement were determined. The usefulness of the clinical severity assessment based on the PVR and CT scores using Z2 under the determined conditions was statistically evaluated. The best agreement with the visual measurement was achieved by the Z2 measurement condition of ≥-600 HU. The areas under the receiver operating characteristic curves, Youden's index, and the sensitivity, specificity, and p-values of the PVR and CT scores by Z2 were as follows: PVR: 0.881, 18.69, 66.7, 94.7, and <0.001; CT score: 0.77, 7.5, 40, 74, and 0.002, respectively. We determined the optimal condition for assessing the PVR of COVID-19 pneumonia using Z2 and demonstrated that the AUC of the PVR was higher than that of CT scores in the assessment of clinical severity. The introduction of new technologies is time-consuming and expensive; our method has high clinical utility and can be promptly used in any facility where Z2 has been introduced.

Evaluation of age-related thymic changes using computed tomography images: A retrospective observational study.

We aimed to investigate if Computed tomography (CT) attenuation values can help improve the identification of age-related changes in the thymus. We assessed CT images of 405 patients aged 0 to 80 years. We measured the area of the anterior mediastinum at the level of the carina and its average CT attenuation value. We evaluated the thymic area, the ratio of the thymus area to the total thoracic area, and the CT attenuation value. Additionally, we evaluated changes in the thymus area in the 0 to 13-year age group. The area of the thymus decreased from birth to the middle 20s. After the middle 20s, the area tended to increase and plateau till after 50 years of age. The ratio of the thymic area to the thoracic area decreased from age 0 to 20 years, but remained stable after 20 years of age. The CT attenuation values were stable from birth to puberty, decreased after puberty, and were stable again in the late 50s and beyond. The thymus of children showed mass formation, but the shape changed with age. No significant differences in the CT attenuation value were found across underlying conditions for the 0 to 13-year age group. The decrease in the CT attenuation values, observed with advancing age, reflects adipose degeneration of the thymus, indicating that by the late 50s, thymic tissue is replaced completely by adipose tissue. Our data suggest that adipose degeneration of the thymus begins after puberty and advances with age.

Pulmonary lymphoepithelial cyst with no prior HIV infection: A case report.

Most lymphoepithelial cysts (LECs) occur in the salivary glands and are considered one of the autoimmune syndromes caused by the human immunodeficiency virus (HIV). In this report, we present a case of pulmonary LEC without prior HIV infection, paying special attention to radiographic features. A chest radiograph revealed an oval mass with a smooth surface, localized in the left lower lung field, which was in direct contact with the diaphragm. Computed tomography showed an oval homogenous mass with a smooth surface in the lower left lobe. Further, magnetic resonance imaging demonstrated that the mass was a homogeneous internal structure with a smooth surface and a slightly high signal in T2-weighted images and a slightly low signal in T1-weighted images. Surgical resection was performed, and pathological examination confirmed the diagnosis of a pulmonary LEC. To the best of our knowledge, no cases of pulmonary LECs without prior HIV infection have been reported in the literature to date, therefore, the case presented here is considered very rare and informative.

Magnetic resonance imaging evaluation of the effectiveness of FemiCushion in pelvic organ prolapse.

AIMS: FemiCushion (FC) is a supportive device for pelvic organ prolapse (POP), but its effectiveness has not been evaluated with imaging studies. This study utilized magnetic resonance imaging (MRI) to evaluate the anatomic changes induced by FC use in patients with severe POP. METHODS: This prospective study examined patients with stage 3 or 4 POP who underwent treatment with FC and received a diagnostic MRI. Measurements were made in the midsagittal plane at rest and during straining with and without FC. The vertical distances from the lowest points of the anterior and posterior vaginal wall (A; P), uterine cervix or vaginal stump (C), and perineal body (PB) to the Pelvic Inclination Correction System line were measured, along with the lengths of the urogenital (UGH) and levator hiatus (LH). RESULTS: Twelve patients were included in the study. The median age was 72 (range, 56-84) years. All reference points were positioned significantly higher with the FC than without the FC (median ΔA: 11 mm, p = 0.005; ΔC: 14 mm, p = 0.011; ΔP: 6 mm, p = 0.008; ΔPB: 7 mm, p = 0.002). Median UGH and LH lengths during straining were significantly shorter with the FC than without the FC (UGH: 44 mm vs. 53 mm, p = 0.002; LH: 60 vs. 65 mm, p = 0.021). CONCLUSIONS: This is the first report on the use of MRI to measure the performance of FC. Our study demonstrates that FC effectively repositioned the organs involved in POP.

Influence of venipuncture point and port chamber site on the risk of catheter fracture in right internal jugular port placements.

BACKGROUND: For subcutaneously implanted central venous ports, some complications due to prolonged placement have been reported. We investigated the appropriate puncture points and port placement sites to prevent catheter fracture in right internal jugular port placement. METHODS: This retrospective study included 709 patients who underwent right internal jugular vein puncture and port implantation in the right precordium between 1 May 2012 and 31 March 2018. The cases were divided into undamaged catheter group and damaged catheter group comprising normal and fracture cases, respectively. The catheter angle, distance from the clavicle, tip position, and curvature radius were measured from fluoroscopic images obtained at the time of implantation. The t-test was used in statistical analysis. RESULTS: Median angles were 91.6° in the undamaged catheter group and 58.0° in the damaged catheter group. Median distances were 26.0 mm in the undamaged catheter group and 36.6 mm in the damaged catheter group. Median tip positions were 51.6 mm in the undamaged catheter group and 37.5 mm in the damaged catheter group. Median curvature radii were 9.2 R in the undamaged catheter group and 7.1 R in the damaged catheter group. Significant differences were found in the angle, height, and curvature radius between the two groups. CONCLUSION: Our results indicate that a venipuncture as close to the clavicle as possible (less than 3 cm) and a gentle catheter curve (close to 90° angle) are associated with a lower risk of catheter fracture.

Leiomyoma treatment by uterine artery embolization using gelatin sponge prepared by the pumping method.

Uterine leiomyoma, a benign tumor, may be treated with drugs, albeit surgical resection is more common. The present study aimed to evaluate the treatment of leiomyoma cases by uterine artery embolization (UAE) using a gelatin sponge prepared by the pumping method. The results of 700 leiomyoma cases treated by UAE in the outpatient department were evaluated. UAE was performed by injecting gelatin sponge prepared by the pumping method into the uterine artery. Among 700 cases, effective cases were 680 (97.2%), ineffective cases were 18 (2.8%) and impossible cases for UAE were 2 (0.2%). Retreatment was required in 23 cases (3.3%). Complication events designated by the Society of Interventional Radiology Clinical Practice Guidelines occurred in 31 cases (4.4%): 1 case showed permanent adverse sequelae, 4 cases required major therapy with a prolonged hospitalization (>48 h) and 10 patients required therapy with minor hospitalization (<48 h). The remaining 16 cases required nominal or no therapy. Follow-up of patients was performed for 599 cases for an average period of 1.2±0.9 years, ranging between 1 month and 6 years. Pregnancy after UAE was observed in 12 cases/15 cycles. Thus, the findings indicate that UAE using gelatin sponge prepared by the pumping method applied to outpatients is a safe and useful treatment procedure.

Mediastinal lung herniation associated with pulmonary sequestration.

Mediastinal lung herniation is a rare condition characterized by protrusion of 1 lower lung through behind the heart into the opposite side of the chest, usually from right to left. We present a case of mediastinal lung herniation associated with pulmonary sequestration, which was confirmed both surgically and pathologically in a 13-year-old girl initially admitted with a diagnosis of pneumonia. Contrast-enhanced computed tomographic images using a multidetector-row computed tomography clearly demonstrated the right lung herniation toward the left and 2 aberrant systemic arteries supplying the sequestered lung mass. These arteries run through the herniated lung from right to left. Additionally, on the basis of pleural anatomy, we discuss herein the difference between a mediastinal lung herniation and horseshoe lung.

Diffusion-weighted MR imaging of early-stage Creutzfeldt-Jakob disease: typical and atypical manifestations.

Creutzfeldt-Jakob disease causes progressive dementia and, eventually, death. The infectious agent is thought to be proteinaceous scrapie particles. Prompt diagnosis is essential to prevent human-to-human transmission. Progressive brain atrophy and areas of high signal intensity in the cerebral cortex and basal ganglia are well-known features of Creutzfeldt-Jakob disease depicted on T2-weighted magnetic resonance (MR) images. However, in the early stage of disease, the appearance of the brain on T2-weighted MR images often is normal, and it may be impossible on that basis to reach a diagnosis. Diffusion-weighted imaging therefore has gained attention as a useful modality for the early diagnosis of Creutzfeldt-Jakob disease. Even before the appearance of the characteristic periodic synchronous discharges on the electroencephalogram, diffusion-weighted images in most cases of Creutzfeldt-Jakob disease depict areas of abnormal signal hyperintensity in the cortex and in the basal ganglia or thalamus. These imaging abnormalities are accompanied by decreased apparent diffusion coefficient values suggestive of restricted diffusion within the tissue. However, if diffusion-weighted imaging findings of abnormal high signal intensity are restricted to the cerebral cortex, it may be necessary to differentiate between Creutzfeldt-Jakob disease and other conditions that may produce progressive dementia (eg, venous hypertensive en-cephalopathy; chronic herpes encephalitis; and the syndrome of mitochondrial myopathy, encephalopathy, lactic acidosis, and strokelike episodes).

Pulmonary adenocarcinoma complicated with pulmonary infarction presented as intrapulmonary metastases: a report of a case.

Pulmonary adenocarcinoma complicated with a pulmonary infarction presenting as an intrapulmonary metastasis is relatively rare. We present a case of pulmonary infarction manifesting as intrapulmonary metastases of lung cancer. A previously healthy 59-year-old woman was admitted to our hospital for evaluation of abnormal shadows in the right lower lung field. Laboratory tests showed no abnormalities except for a slight elevation of carcinoembryonic antigens (CEAs). Computed tomography (CT) of the chest revealed a hilar mass lesion with parenchymal lesions in the periphery of the right lower lobe, highly suspected to be a pulmonary adenocarcinoma with intrapulmonary metastases. A diagnosis of pulmonary adenocarcinoma was confirmed by a transbronchial brushing examination. A right middle and lower bilobectomy with mediastinal lymph node dissection was due to hilar lymphadenopathy and a lower lobe invasion of the main tumor. Histopathological findings of the resected specimens revealed poorly differentiated adenocarcinoma of the lung with N1 (number 11i and 12 l) disease and multiple pulmonary infarctions with coagulation necrosis and recanalization. Our case suggests that pulmonary infarction associated with lung cancer should be considered as one important cause of peripheral pulmonary nodules.

Serial diffusion-weighted MRI of Creutzfeldt-Jakob disease.

OBJECTIVE: The objective of our study was to evaluate the clinical usefulness of MRI findings, including diffusion-weighted imaging, in relation to the clinical signs and symptoms of Creutzfeldt-Jakob disease (CJD). MATERIALS AND METHODS: We reviewed nine cases of CJD in which MRI was performed from the early to terminal phase of the disease. MRI findings were correlated before (early phase) and after (intermediate phase) the onset of the characteristic clinical findings of myoclonus and periodic synchronous discharges on electroencephalograms. The chronologic changes in imaging findings were followed from the akinetic mutism to the terminal phase of the disease (terminal phase). T2-weighted images had been obtained in all the patients, and diffusion-weighted images and FLAIR images had been obtained in six patients. We evaluated the images for the presence and location of abnormal signal intensities. RESULTS: During the early phase, the T2-weighted images showed no abnormal findings. The diffusion-weighted images, however, revealed abnormal high signal intensities in the cortex in all patients and in the basal ganglia in five patients. In two cases, there were abnormal signals on FLAIR images that corresponded to diffusion-weighted imaging abnormalities. During the intermediate phase, the area of the high signal intensities on the diffusion-weighted images had expanded and progressive cerebral atrophy had become apparent. During the terminal phase, abnormal high signal intensities in the cerebral cortex and basal ganglia on the diffusion-weighted images in one patient disappeared. CONCLUSION: Diffusion-weighted imaging is extremely useful in detecting CJD during the very early phase-even before the onset of characteristic clinical findings.

Acute cerebral infarction: effect of JPEG compression on detection at CT.

PURPOSE: To evaluate the effect of Joint Photographic Experts Group (JPEG) compression ratios of 10:1 and 20:1 on detection of acute cerebral infarction at computed tomography (CT). MATERIALS AND METHODS: CT images obtained in 25 patients with acute cerebral infarction and 25 patients with no lesions were compressed by means of a JPEG algorithm at ratios of 10:1 and 20:1. Normal and abnormal sections (on original and compressed images) were reviewed by using a color soft-copy computed monochrome cathode ray tube monitor. Five observers rated the presence or absence of a lesion with a 50-point scale (0, definitely absent; 25, equivocal; and 50, definitely present). Diagnostic accuracy was evaluated with receiver operating characteristic (ROC) curve analysis. Significant difference was defined as a P value less than.05 for the area tested with a two-tailed paired Student t test. RESULTS: At ROC analysis, no statistically significant difference was detected for all cases considered together (Az [area under the ROC curve] = 0.887 +/- 0.038 [mean +/- SD] on noncompressed images, Az = 0.897 +/- 0.038 on 10:1 compressed images, and Az = 0.842 +/- 0.073 on 20:1 compressed images; P >.05). CONCLUSION: JPEG compression at ratios of 10:1 and 20:1 was tolerated in the detection of acute cerebral infarction at CT.