[Experience with Surgical Stabilization for Traumatic Rib Fractures and Sternal Fractures].

The treatment of traumatic rib fractures and sternal fractures have focused on pain and respiratory management, and conservative treatment has been recommended. Recently, however, a number of case series from abroad have been reported and demonstrated the usefulness of surgical stabilization of rib fractures (SSRF) and sternal fractures (SSSF). We have experienced seven cases of SSRF and two cases of SSSF at International University Health and Welfare Narita Hospital and Atami Hospital. Based on our experienced cases, we have outlined the preoperative evaluation, indication for surgery, timing of surgery, surgical techniques, and postoperative course. Of these nine cases, the clinical course of two cases of SSRF and one case of SSSF were detailly presented. The surgical indications and techniques for traumatic rib fractures and sternal fractures vary from institution to institution, and there is no single optimal treatment. We hope that the accumulation of cases, and discussions will help to build a higher quality evidence for surgical treatment of thoracic trauma in Japan.

Surgical treatment for chronic pulmonary coccidioidomycosis: a retrospective study from a single institution.

PURPOSE: Coccidioidomycosis, caused by the Coccidioides species, is a well-known disease in the Southwestern United States and North Mexico, with scattered reports in Latin America countries. While this disease is still rare in Japan and other Asian countries, its incidence has been increasing over the last two decades. Coccidioides species are highly infectious and require caution when encountered. This study presents a case series of chronic pulmonary coccidioidomycosis surgically treated at a single institution. METHODS: We conducted a retrospective chart review of six patients who underwent lung resection for pulmonary coccidioidomycosis at Chiba University Hospital between January 2007 and December 2021. RESULTS: All six patients had travelled to the Southwestern United States. Preoperative serology was negative for the anti-Coccidioides antibody in four patients and positive in two. Chest computed tomography revealed a single, well-defined round nodule in all patients. Preoperative biopsy taken from three patients failed to obtain a definitive diagnosis. Histopathological examination of the resected pulmonary nodules revealed granulomas that contained numerous spherules with many endospores, thereby confirming the diagnosis of pulmonary coccidioidomycosis. CONCLUSIONS: Pulmonary coccidioidomycosis should be suspected based on travel history and radiological findings. Meticulous care should be taken during specimen processing to prevent cross infection.

Parameter search of a CPG network using a genetic algorithm for a snake robot with tactile sensors moving on a soft floor.

When a snake robot explores a collapsed house as a rescue robot, it needs to move through various obstacles, some of which may be made of soft materials, such as mattresses. In this study, we call mattress-like environment as a soft floor, which deforms when some force is added to it. We focused on the central pattern generator (CPG) network as a control for the snake robot to propel itself on the soft floor and constructed a CPG network that feeds back contact information between the robot and the floor. A genetic algorithm was used to determine the parameters of the CPG network suitable for the soft floor. To verify the obtained parameters, comparative simulations were conducted using the parameters obtained for the soft and hard floor, and the parameters were confirmed to be appropriate for each environment. By observing the difference in snake robot's propulsion depending on the presence or absence of the tactile sensor feedback signal, we confirmed the effectiveness of the tactile sensor considered in the parameter search.

Modified Clagett procedure for acute pleural empyema.

Pleural empyema often requires surgical intervention; however, surgical invasiveness should be minimized. We utilized the modified Claget procedure as an alternative to thoracoplasty for acute pleural empyema with a dead space. The procedure was performed as follows: first, 500 mg of kanamycin and 500,000 units of polymyxin sulfate dissolved in 10-100 ml saline was instilled intrapleurally via tube thoracostomy. The chest tube was clamped overnight and then removed. The modified Clagett procedure might be effective for acute pleural empyema with a dead space without pulmonary or bronchopleural fistula. We report our successful experience of performing modified Clagett procedure for pleural empyema with a dead space, through a detailed case presentation.

Successful management of a mediastinum abscess with sternum destruction caused by MSSA bloodstream infection.

BACKGROUND: Multiple deep organ abscesses associated with Staphylococcus aureus bloodstream infection (SAB) have a high mortality rate, requiring rapid removal or drainage of infective foci with long-term appropriate antimicrobial therapy. Cases in which infective foci cannot be completely removed are challenging for their management. CASE PRESENTATION: A 77-year-old man developed multiple deep organ abscesses associated with SAB. The left anterior chest subcutaneous abscess continued into the right anterior mediastinum and had extensively destroyed the sternum. Necrotizing fasciitis was observed in the bilateral feet. The anterior mediastinum abscess was drained percutaneously, and the chest wall abscess was incised cautiously without causing an external pneumothorax. On the next day, right-sided pyothorax had developed, requiring pleural drainage. On the third day, debridement of anterior chest wall abscess followed by concurrent thoracoscopic pleural curettage and debridement of bilateral feet were performed. Thorough sternal debridement was not performed, considering the risk of respiratory failure due to the sternal defects. On the 24th day, sternum debridement and incisional drainage of sciatic rectus fossa abscess, which had been present since the time of admission, were performed to control persistent infection. The caudal half of the sternal body was resected, leaving the costal cartilage attachments. The general condition further improved without postoperative respiratory failure after the second surgery, leading to a transfer to the general ward on the 43rd day. CONCLUSIONS: We successfully treated the severe multiple deep organ abscesses, including a mediastinum abscess with sternum destruction, by repeated removal of the infective foci while avoiding respiratory failure due to excessive debridement of the anterior chest wall, including the sternum.

Apparent diffusion coefficient and intravoxel incoherent motion-diffusion kurtosis model parameters in invasive breast cancer: Correlation with the histological parameters of whole-slide imaging.

OBJECTIVES: To evaluate the correlation of ADC and IVIM-diffusion kurtosis (DK) model parameters with quantitative histological parameters of whole-slide imaging (WSI). METHODS: This retrospective study (September 2015-July 2016) included 37 consecutive patients (all females; median age: 64 years, range, 41-82 years), each with a single invasive breast ductal carcinoma lesion with a mass appearance on preoperative MRI. DWI with b-values of 0, 50, 100, 300, 550, 850, and 1000 s/mm2 was performed. ADC maps were generated with b-values of 50 and 850 s/mm2. The IVIM-DK model was analysed using the following formula: [Formula: see text] where S is the signal intensity, b is the b-value, f is the perfusion fraction, D* is the pseudo-diffusion coefficient of the vascular component, D is the diffusion coefficient of the non-vascular component, and k is the diffusion kurtosis. Whole tumour segmentation was performed to obtain the mean ADC, f, D*, D, and k. Quantitative histological parameters were obtained using cytokeratin immunostaining and WSI. The correlation of ADC and IVIM-DK model parameters with quantitative histological parameters was examined by Pearson's correlation. RESULTS: The ADC was significantly correlated with the area ratio of interstitium (r = 0.53, p = 0.00082) and entropy (r = -0.58, p = 0.00019). k was significantly correlated with the area ratio of cancer cell nuclei (r = 0.53, p = 0.00079). CONCLUSIONS: Since the ADC reflected the area ratio of interstitium and entropy, and diffusion kurtosis reflected the area ratio of cancer cell nuclei, these parameters may be effective in distinguishing between benign and malignant breast tumours and in grading breast cancer.

Differential gene analysis during the development of obliterative bronchiolitis in a murine orthotopic lung transplantation model: A comprehensive transcriptome-based analysis.

BACKGROUND: Obliterative bronchiolitis (OB) is a known issue during minor histocompatibility antigen (mHA) disparity during lung transplantation. This study evaluated gene expression in a murine orthotropic lung transplantation model using microarray analysis. METHODS: Left lungs from C57BL/10(H-2b) donor mice were transplanted into mHA-mismatched C57BL/6(H-2b) recipient mice. Three groups (OB, non-OB, and sham controls) were confirmed pathologically and analyzed. Gene expression changes in the lung grafts were determined by microarray and immunohistochemical staining, and genes were verified by quantitative PCR in the lungs and mediastinal lymph nodes (LNs). RESULTS: A total of 1343 genes were upregulated in the OB lungs compared to the sham group. Significant upregulation was observed for genes related to innate, e.g. Tlr2 and CCL3 and adaptive immunity, e.g. H2-ab1 and Il-21. Positive labeling for MHC class II antigen was observed in the bronchial epithelium of OB accompanied with B cells. We found increased Tlr2, Ccl3, H2-ab1, Il-21, Ighg3, Ifng, and Pdcd1 mRNA expression in the OB lung, and increased Il-21, Ighg3, and Pdcd1 expression in the OB LNs. CONCLUSIONS: Adaptive and innate immune reactions were involved in OB after lung transplantation, and genetic examination of related genes could be used for detection of OB.

The combination of endobronchial elastography and sonographic findings during endobronchial ultrasound-guided transbronchial needle aspiration for predicting nodal metastasis.

BACKGROUND: During endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA), the sonographic findings of B-mode imaging, as well as endobronchial elastography, can be obtained noninvasively and used for the prediction of nodal metastasis. METHODS: Patients with lung cancer or suspected lung cancer who underwent EBUS-TBNA were recorded prospectively and reviewed retrospectively. Both the B-mode sonographic and elastographic findings were independently evaluated for each lymph node. The sonographic features were classified according to previously published criteria. If oval shape, indistinct margins, homogenous echogenicity, and the absence of coagulation necrosis sign were all observed by B-mode imaging, then the lymph node was judged to be benign by sonographic imaging. In addition, if the stiffer area comprised more than 31% of the entire lymph node area, then the lymph node was judged to be malignant by elastography. We compared the results of these imaging-based predictions with the pathological diagnoses. RESULTS: The prevalence of nodal metastasis was 78/228 (34.2%). B-mode sonography predicted 95.8% of benign lymph nodes, and elastography predicted 72.1% of malignant lymph nodes. By combining the two modalities, 59 of 71 (83.1%) lymph nodes judged as malignant by both analyses were pathologically proven to be malignant, and 101 of 105 (96.2%) lymph nodes judged as benign by both analyses were pathologically proven to be benign. CONCLUSION: The combination of elastography and sonographic findings showed good sensitivity and a high negative predictive value, which may facilitate selecting the most suspicious lymph nodes for biopsy. KEY POINTS: Significant findings of the study. The combination of endobronchial elastography and sonography resulted in a higher diagnostic yield than either modality alone for predicting benign and malignant lymph nodes in patients with lung cancer. WHAT THIS STUDY ADDS: The combination of endobronchial elastography and sonography will help clinicians identify the most suspicious lymph nodes for puncturing during EBUS-TBNA, which may improve the efficiency of EBUS-TBNA.

Atrophy of the ipsilateral mammillary body in unilateral hippocampal sclerosis shown by thin-slice-reconstructed volumetric analysis.

PURPOSE: Conventional volumetric analysis could not detect ipsilateral atrophy of the mammillary body in patients with unilateral hippocampal sclerosis. By using thin-slice-reconstructed volumetric analysis, we investigated whether the mammillary body volume is smaller on the hippocampal sclerosis side than in healthy subjects or the non-hippocampal sclerosis side. METHODS: This retrospective study included 45 patients with unilateral hippocampal sclerosis and 30 healthy subjects. Three-dimensional T1WI of 1 mm thicknesses were oversampled to a thickness of 0.2 mm (thin-slice-reconstructed images), and the mammillary bodies were segmented manually to determine mammillary body volume on each side. Mammillary body volumes on the hippocampal sclerosis side were compared with those in healthy subjects or the non-hippocampal sclerosis side. RESULTS: In patients with right hippocampal sclerosis, right mammillary body volume was both significantly smaller than that in healthy subjects (30.3 ± 10.3 vs. 43.3 ± 8.07 mm3, P < 0.001) and significantly smaller than the left mammillary body volume in each patient (30.3 ± 10.3 vs. 41.4 ± 10.1 mm3, P < 0.001). Similarly, in patients with left hippocampal sclerosis, left mammillary body volume was both significantly smaller than that in healthy subjects (37.7 ± 11.2 vs. 47.0 ± 8.65 mm3, P < 0.001) and significantly smaller than right mammillary body volume in each patient (37.7 ± 11.2 vs. 42.5 ± 7.78 mm3, P = 0.044). CONCLUSIONS: In this study, thin-slice-reconstructed volumetric analysis showed that, in patients with unilateral hippocampal sclerosis, mammillary body volume on the hippocampal sclerosis side is smaller than that in healthy subjects and the non-hippocampal sclerosis side.

Ultrafast Dynamic Contrast-Enhanced Breast MRI: Kinetic Curve Assessment Using Empirical Mathematical Model Validated with Histological Microvessel Density.

RATIONALE AND OBJECTIVES: To evaluate whether parameters from empirical mathematical model (EMM) for ultrafast dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) correlate with histological microvessel density (MVD) in invasive breast cancer. MATERIALS AND METHODS: Ninety-eight consecutive patients with invasive breast cancer underwent an institutional review board-approved ultrafast DCE-MRI including a pre- and 18 postcontrast whole breast ultrafast scans (3 seconds) followed by four standard scans (60 seconds) using a 3T system. Region of interest was placed within each lesion where the highest signal increase was observed on ultrafast DCE-MRI, and the increase rate of enhancement was calculated as follows: ΔS = (SIpost - SIpre)/SIpre. The kinetic curve obtained from ultrafast DCE-MRI was analyzed using a truncated EMM: ΔS(t) = A(1 - e-αt), where A is the upper limit of the signal intensity, α (min-1) is the rate of signal increase. The initial slope of the kinetic curve is given by Aα. Initial area under curve (AUC30) and time of initial enhancement was calculated. From the standard DCE-MRI, the initial enhancement rate (IER) and the signal enhancement ratio (SER) were calculated as follows: IER = (SIearly - SIpre)/SIpre, SER = (SIearly - SIpre)/(SIdelayed - SIpre). The parameters were compared to MVD obtained from surgical specimens. RESULTS: A, α, Aα, AUC30, and time of initial enhancement significantly correlated with MVD (r = 0.29, 0.40, 0.51, 0.43, and -0.32 with p = 0.0027, p < 0.0001, p < 0.0001, p < 0.0001, and p = 0.0012, respectively), whereas IER and SER from standard DCE-MRI did not. CONCLUSION: The parameters of the EMM, especially the initial slope or Aα, for ultrafast DCE-MRI correlated with MVD in invasive breast cancer.

Quantitative characterization of carotid plaque components using MR apparent diffusion coefficients and longitudinal relaxation rates at 3T: A comparison with histology.

BACKGROUND: There is limited evidence of parametric MR mapping to characterize carotid plaques associated with cerebral ischemic events. PURPOSE: To explore the apparent diffusion coefficients (ADCs) and longitudinal relaxation rates (R1 ) of carotid plaques, including areas of hemorrhage, lipid-rich/necrotic core (LR/NC) without hemorrhage, and fibrous tissue (Fbr) STUDY TYPE: Prospective. SUBJECTS: Twelve patients who underwent carotid endarterectomy. FIELD STRENGTH/SEQUENCE: R1 was measured using double angle Look-Locker acquisition on 3T systems. Single-shot spin-echo echo-planar imaging with fat suppression and outer-volume suppression (OVS-DWEPI) with b values of 10 and 500 s/mm2 was used for diffusion-weighted imaging. ASSESSMENT: A phantom study using diluted gadolinium solutions and polyvinyl alcohol solutions was used to validate the two protocols. Regions of interest (ROIs) were manually outlined on MR images for areas of LR/NC, hemorrhage, and Fbr based on histological cross-sections. Pixel-based R1 and ADC values in the ROIs were plotted for each component. The probability density function of the plots determined the optimum contours to separate the three components in the ADC-R1 plane. The LR/NC, hemorrhage, and Fbr regions were mapped on MR images based on the above results and compared to histological results. STATISTICAL TESTS: The R1 values of the phantom measurements were tested using Bland-Altman analysis. The accuracies of the MRI classification were calculated. RESULTS: R1 values <8 s-1 calculated using our method agreed with those calculated using an inversion-recovery fast-spin-echo sequence (error, ≤0.1 s-1 ). ADC values obtained using OVS-DWEPI were 4.1% higher than those obtained using standard echo-planar imaging. LR/NC (R1 , 0.4-1.2 s-1 ; ADC, 0-1.5 µm2 /ms), hemorrhage (R1 ≥ 1.5 s-1 ; ADC, 0.5-1.5 µm2 /ms), and Fbr (R1 , 0.2-0.8 s-1 ; ADC, 1.5-2.9 µm2 /ms) were separated on the plots. The accuracies of MRI classification were LR/NC, 0.86; hemorrhage, 0.79; and Fbr, 0.77. CONCLUSION: The combination of ADC and R1 values measured using our method enabled differentiation among LR/NC, hemorrhage, and Fbr. LEVEL OF EVIDENCE: 1 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2018;48:1657-1667.

Sclerosing pneumocytoma diagnosed by preoperative endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA).

BACKGROUND: Sclerosing pneumocytoma is a rare lung tumor that is usually recognized as a solitary nodule in the lung. Surgical removal is recommended; however, its clinical diagnosis is still an issue because it is difficult to differentiate from lung adenocarcinomas using a tiny sample obtained from biopsy. CASE PRESENTATION: We report a case of pulmonary sclerosing pneumocytoma located in the upper lobe of the right lung of a 34-year-old woman, which was diagnosed before surgery by endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA). A 3-cm irregular mass was detected by chest X-ray without any symptoms. She was referred to our hospital after being followed for 10 years in her previous clinic. During this follow-up period, the tumor had grown to 5 cm. We performed the EBUS-TBNA for the diagnosis. The histological findings obtained by EBUS-TBNA consisted of alveolar type 2-like cells that were positive for napsin A and round cells that were positive for vimentin. Based on these immunostaining results, we successfully diagnosed sclerosing pneumocytoma before surgery. Right upper lobectomy was performed, and the pathological diagnosis of the surgical specimen was also confirmed as sclerosing pneumocytoma. CONCLUSIONS: We herein report a case of sclerosing pneumocytoma, which was clinically diagnosed by EBUS-TBNA and resected surgically.

[A Case of Axillary Nodal Metastasis of Adenocarcinoma of an Unknown Primary Site Effectively Treated with Anti-HER2plus AC plus Paclitaxel Therapy].

A 68-year-old woman who presented with a left axillary mass was admitted. A computed tomography scan showed swelling ofthe left axillary and supraclavicular lymph nodes, but magnetic resonance imaging(MRI)and fluorodeoxyglucose positron emission tomography(FDG-PET)did not reveal these primary sites. Histological findings of the axillary mass revealed a HER2-positive adenocarcinoma. We diagnosed the patient with axillary nodal metastasis ofadenocarcinoma ofan unknown primary site and treated her with neoadjuvant chemotherapy including paclitaxel and trastuzumab followed by doxorubicin and cyclophosphamide. The lesions almost disappeared after 3 courses of chemotherapy and she showed a pathologically complete response(CR)after surgery. The patient has been recurrence-free since the operation owing to treatment with adjuvant trastuzumab.

Differential diagnosis of primary intrapulmonary thymoma: a report of two cases.

Primary intrapulmonary thymomas (PITs), which are intrapulmonary tumors without an associated mediastinal component, are very rare. The diagnosis of a PIT can be difficult. Here, we report two cases of resected PITs that were difficult to differentiate from other lung tumors. The patients, of a 62-year-old man and a 64-year-old woman, had no significant symptoms and were both referred to our hospital due to the presence of an abnormal shadow on chest computed tomography (CT). The patients underwent (18)F-fluorodeoxyglucose positron emission tomography-CT (FDG-PET/CT) and subsequently tumor excision. A PIT was confirmed histopathologically in the surgical specimens from both patients. In one case, the tumor consisted of a type A thymoma without abnormal FDG uptake. In the other case, the tumor consisted of a type B2 thymoma presenting with weak FDG uptake. This report thus documents two cases of PITs with different histopathologic and FDG-PET/CT findings. Thoracoscopic surgery is essential in the differential diagnosis between PITs and other lung tumors.

Quantitative activation-induced manganese-enhanced MRI reveals severity of Parkinson's disease in mice.

We demonstrate that activation-induced manganese-enhanced magnetic resonance imaging with quantitative determination of the longitudinal relaxation time (qAIM-MRI) reveals the severity of Parkinson's disease (PD) in mice. We first show that manganese ion-accumulation depends on neuronal activity. A highly active region was then observed by qAIM-MRI in the caudate-putamen in PD-model mice that was significantly correlated to the severity of PD, suggesting its involvement in the expression of PD symptoms.

Noise Power Spectrum in PROPELLER MR Imaging.

The noise power spectrum (NPS), an index for noise evaluation, represents the frequency characteristics of image noise. We measured the NPS in PROPELLER (Periodically Rotated Overlapping ParallEL Lines with Enhanced Reconstruction) magnetic resonance (MR) imaging, a nonuniform data sampling technique, as an initial study for practical MR image evaluation using the NPS. The 2-dimensional (2D) NPS reflected the k-space sampling density and showed agreement with the shape of the k-space trajectory as expected theoretically. Additionally, the 2D NPS allowed visualization of a part of the image reconstruction process, such as filtering and motion correction.

Endobronchial ultrasound-guided transbronchial needle aspiration in a patient with pericardial mesothelioma.

Pericardial mesothelioma is a very rare pericardial tumor. Diagnosing pericardial disease can be challenging, and obtaining an antemortem diagnosis of pericardial mesothelioma is particularly difficult. We herein report the case of a 60-year-old man with pericardial mesothelioma diagnosed on endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA). Chest computed tomography showed a mass surrounding the pericardium, and EBUS-TBNA of the right inferior paratracheal and subcarinal stations was consequently performed. No uptake was noted on (18)F-fluorodeoxy glucose positron emission tomography, other than in the pericardial mass. The results of histological and immunohistochemical examinations indicated the features of malignant mesothelioma. We therefore diagnosed the patient with pericardial mesothelioma, which was subsequently confirmed at autopsy.

Frequency of brain metastases in non-small-cell lung cancer, and their association with epidermal growth factor receptor mutations.

BACKGROUND: The brain is a frequent site of metastases from non-small-cell lung cancer (NSCLC). We analyzed the frequency of brain metastases (BMs) from NSCLC in the era of magnetic resonance images, and evaluated the correlation between epidermal growth factor receptor (EGFR) mutations and BMs among East Asian patients. METHODS: Frequency, number, and size of BMs, and survival of 1,127 NSCLC patients were retrospectively reviewed. Mutation status of EGFR was evaluated in all cases, and its association with BMs was statistically evaluated. RESULTS: EGFR mutations were found for 331 cases (29.4 %). BM was the cause of primary symptoms for 52 patients (4.6 %), and found before initiation of treatment for 102 other patients (9.1 %); In addition to these 154 patients, 107 patients (9.5 %) developed BMs, giving a total of 261 patients (23.2 %) who developed BMs from 1,127 with NSCLC. BM frequency was higher among EGFR-mutated cases (31.4 %) than EGFR-wild cases (19.7 %; odds ratio: 1.86; 95 % confidence interval (CI) 1.39-2.49; P < 0.001). BMs from EGFR-mutated NSCLC were small, but often became disseminated. EGFR mutations accounted for 39.9 % of BMs, but patient survival after BMs was significantly longer for EGFR-mutated cases than for EGFR-wild cases (hazard ratio: 2.23; 95 % CI 1.62-3.10; P < 0.001). CONCLUSIONS: Patients with EGFR-mutated NSCLC were more likely to develop BMs, but apparently also survived longer after BMs.

Evaluation of the biodistribution and radiation dosimetry of the 18F-labelled amyloid imaging probe [18F]FACT in humans.

BACKGROUND: The biodistribution and radiation dosimetry of the 18F-labelled amyloid imaging probe ([18F] FACT) was investigated in humans. METHODS: Six healthy subjects (three males and three females) were enrolled in this study. An average of 160.8 MBq of [18F] FACT was intravenously administered, and then a series of whole-body PET scans were performed. Nineteen male and 20 female source organs, and the remainder of the body, were studied to estimate time-integrated activity coefficients. The mean absorbed dose in each target organ and the effective dose were estimated from the time-integrated activity coefficients in the source organs. Biodistribution data from [18F] FACT in mice were also used to estimate absorbed doses and the effective dose in human subjects; this was compared with doses of [18F] FACT estimated from human PET data. RESULTS: The highest mean absorbed doses estimated using human PET data were observed in the gallbladder (333 ± 251 µGy/MBq), liver (77.5 ± 14.5 µGy/MBq), small intestine (33.6 ± 30.7 µGy/MBq), upper large intestine (29.8 ± 15.0 µGy/MBq) and lower large intestine (25.2 ± 12.6 µGy/MBq). The average effective dose estimated from human PET data was 18.6 ± 3.74 µSv/MBq. The highest mean absorbed dose value estimated from the mouse data was observed in the small intestine (38.5 µGy/MBq), liver (25.5 µGy/MBq) and urinary bladder wall (43.1 µGy/MBq). The effective dose estimated from the mouse data was 14.8 µSv/MBq for [18F] FACT. CONCLUSIONS: The estimated effective dose from the human PET data indicated that the [18F] FACT PET study was acceptable for clinical purposes.