A Giant Urachal Accessory Spleen: Case Report.

Accessory spleen (AS) refers to single or multiple splenic tissues which appear outside the relative normal spleen position results from embryonic dysplasia similar in structure and function to the spleen. AS is frequently observed in the splenic hilus and or adjacent to the tail of pancreas, and only a few cases occurred in the pelvic cavity. We present an extremely rare AS case in urachus, which was initially considered as an urachal neoplasm revealed on CT images with big mass. However, the postoperative pathology confirmed it was an AS that had not been reported at urachal before. Urachal AS can be misdiagnosed as a tumor, so it is vital to make an accurate imaging preoperative diagnosis to avoid unnecessary biopsy and surgery.

Imaging findings of inflammatory pseudotumor-like follicular dendritic cell sarcoma of the spleen: A case report and literature review.

Inflammatory pseudotumor-like follicular dendritic cell sarcoma (IPT-like FDCS) is a low-grade malignant tumor type caused by the proliferation of follicular dendritic cells. It is a distinct subtype of FDCS that is rarely encountered in the clinic and is overwhelmingly associated with Epstein-Barr virus infection. As it is a sporadic disease with a low specificity of clinical and imaging manifestations, it is less frequently considered a diagnosis, resulting in a low preoperative diagnostic rate and easy misdiagnosis. The present study reported the ultrasound, CT and MRI features of a patient with splenic IPT-like FDCS and discussed this rare subtype of FDCS based on a review of previously published literature to provide radiologists with a broader understanding of the differential diagnosis of splenic lesions.

Metastatic embryonal rhabdomyosarcoma of the breast: A case report and literature review.

Rhabdomyosarcoma (RMS) is a common malignancy in children, but embryonal rhabdomyosarcoma (ERMS) deposits rarely occur in the breast in adults. Therefore, little is known about magnetic resonance imaging (MRI) features of breast metastases from RMS, especially the embryonal type. We reported a case of a 22-year-old woman who was diagnosed with ERMS at left foot 2 years ago and accepted operation and chemotherapy. She was confirmed to have breast metastases from the left foot. Successive imaging examinations were performed 3 months apart. Breast ultrasound indicated a benign lesion, and further examination did not reveal any bone metastases. However, predominant restricted diffusion and rim contrast enhancement on MRI combined with the patient's medical history suggested a malignancy of BI-RADS 5. After 3 months, breast ultrasound revealed masses detected last time became larger and lobulated. In addition, internal heterogeneous intensity and rim contrast enhancement with restricted diffusion were revealed on MRI. We speculated that typical MRI findings of breast metastases from RMS may include iso- to hypointensity on T1WI, heterogeneous hyperintensity on T2WI, and circular enhancement with restricted diffusion. Moreover, mild peritumoral edema, rapid expansion of necrosis, and ascending time-intensity curve detected on MRI may be features of the ERMS type.

Inflammatory Myofibroblastoma of the Breast: A Case Report.

Inflammatory myofibroblastic tumor (IMT) is a rare tumor with low-grade malignant risk mainly occurring in soft tissues and lungs, and it is extremely rare in the breast. Meanwhile, imaging findings of the tumor often present with non-specific features that lead to misdiagnosis and delayed treatment. Here, we report a case of inflammatory myofibroblastic tumor in the breast with the imaging findings of mammography, magnetic resonance imaging (MRI), and pathologic findings to improve the understanding of the disease. The patient was treated by surgical operation, and was followed up for 44 months, no local recurrence and distant metastasis.

Case Report: Solitary Extramedullary Plasmacytoma in the Cervix Misdiagnosed as Cervical Cancer.

Solitary plasmacytoma (SP) is a malignant tumor caused by the monoclonal proliferation of plasma cells, representing less than 5% of plasma cell tumors. SP can be categorized into two groups: solitary bone plasmacytoma (SBP) and solitary extramedullary plasmacytoma (SEP). SEP most commonly occurs in the head and neck and is rarely located in the reproductive system. Here, we report a case of a 77-year-old woman with SEP in the cervix who had a 7-day history of vaginal bleeding. Ultrasonography and magnetic resonance imaging (MRI) showed an oval mass in the cervix, which was initially considered as neoplastic lesions and highly suspected to be cervical cancer, but cervical leiomyoma and other benign tumors cannot be completely excluded. Subsequently, cervical biopsy showed that the tumor was SEP, and then the patient underwent surgery. The postoperative pathological diagnosis was also SEP, which confirmed the radiologist's misjudgment. In conclusion, SEP that occurs in the cervix is remarkably rare, and only nine cases have been reported in the cervix. No case reports to date have described in detail the imaging findings of cervical SEP. This study demonstrates the MRI imaging characteristics of a patient with SEP of the cervix and reviews the imaging findings of SEP reported in the previous literature, in order to provide more extensive insights for radiologists to consider the differential diagnosis of cervical lesions.

Aberrant Structural and Functional Developmental Trajectories in Children With Intellectual Disability.

Intellectual disability (ID) is associated with aberrant structural and functional development of the brain, yet how the dynamical developmental changes of the structure and function of ID from childhood to around puberty remains unknown. To explore the abnormal developmental trajectories of structure and function, 40 children with ID aged 6-13 years and 30 sex-, age-, and educational level-matched healthy controls (HC) with age range from 6 to 13 were recruited. The automatic voxel-based morphometry (VBM) and resting-state functional connectivity (FC) analyses were adopted to delineate the structural and functional differences. Significantly decreased total gray matter volume (GMV) and white matter volume (WMV) in children with ID were found, and the developmental trajectories of GMV and WMV in children with ID showed an opposite direction as compared with HC. The voxel-wise VMB analysis further revealed significantly increased GMV in the dorsal medial prefrontal cortex (dmPFC), bilateral orbital part of the inferior frontal gyrus (orb_IFG.L, orb_IFG.R), right cuneus (cuneus.R), and bilateral middle frontal gyrus (MFG.L, MFG.R) in children with ID. The following seed-based whole-brain functional connectivity analyses of the brain areas with changed GMV found decreased FCs between the cuneus.R and left intraparietal sulcus (IPS.L) and between the MFG.R and anterior cingulate cortex (ACC) in children with ID. Moreover, negative correlations between GMV values in the dmPFC, orb_IFG.L, cuneus.R, and intelligence quotient (IQ) scores and positive correlations between the FCs of the cuneus.R with IPS.L and MFG.R with ACC and IQ scores were found in children with ID and HC. Our findings provide evidence for the abnormal structural and functional development in children with ID and highlight the important role of frontoparietal network in the typical development. The abnormal development of GMV and functional couplings found in this study may be the neuropathological bases of children with ID.

Aberrant Dynamics of Regional Coherence Measured by Resting-State fMRI in Children With Benign Epilepsy With Centrotemporal Spikes (BECTS).

Objective: To explore the dynamic features of intrinsic brain activity measured by fMRI in children with benign epilepsy with centrotemporal spikes (BECTS) and examine whether these indexes were associated with behaviors. Methods: We recruited 26 children with BECTS (10.35 ± 2.91 years) and 26 sex-, and age-matched (11.35 ± 2.51 years) healthy controls (HC) and acquired resting-state functional magnetic resonance imaging (rs-fMRI) and behavioral data. Dynamic regional homogeneity (dReHo), including mean and coefficient of variation (CV) metrics derived from the rs-fMRI data, and were compared between the BECTS and the HC groups. Results: Significantly decreased mean dReHo in bilateral supramarginal gyrus, left middle temporal gyrus (MTG.L), left postcentral gyrus and superior occipital gyrus were found in children with BECTS. Meanwhile, increased CV of dReHo in MTG.L and right fusiform in children with BECTS was revealed compared with HC. Further analyses of functional connectivity revealed decreased global signal FC existed in similar regions, linked with linguistic, social cognition, and sensorimotor processes, in children with BECTS compared with HCs. Moreover, the association analyses showed that the CV of dReHo in MTG.L was positively associated with age and a negative correlation was found between mean dReHo of MTG.L and disease duration. Besides, the CV of dReHo in MTG.L was found positively associated with the intelligence quotient (IQ) language scores and full IQ scores in children with BECTS, and the CV of dReHo in the left inferior temporal gyrus and Rolandic operculum were positively correlated with IQ operation scores and full IQ scores. Conclusion: Aberrant dynamic regional coherence in sensorimotor, linguistic, and lateral temporal regions suggests dynamical interplay that underlying cognitive performance in children with BECTS, suggesting an intrinsic dynamic mechanism for BECTS.

Frequency-Dependent Changes in Interhemispheric Functional Connectivity Measured by Resting-State fMRI in Children With Idiopathic Generalized Epilepsy.

Epilepsy is associated with abnormal spatiotemporal changes in resting-state brain connectivity, but how these changes are characterized in interhemispheric coupling remains unclear. This study aimed to characterize frequency-dependent alterations in voxel-wise mirrored homotopic connectivity (VMHC) measured by resting-state functional magnetic resonance imaging (rs-fMRI) in children with idiopathic generalized epilepsy (IGE). Rs-fMRI data were collected in 21 children with IGE and 22 demographically matched children with typical development. We used three resting-state frequency bands (full, 0.01-0.08 Hz; slow-4, 0.027-0.073 Hz; slow-5, 0.01-0.027 Hz) to compute VMHC and locate the significant foci. Voxel-wise p <0.001 and cluster-level p <0.05 cluster-level family-wise error correction was applied. In between-group comparisons, we identified that the full and higher frequency (slow-4) bands showed similar reductions in VMHC including Rolandic operculum, putamen, superior frontal, lateral parietal, middle cingulate, and precuneus in children with IGE. In the lower frequency band (slow-5), we identified specific reductions in VMHC in orbitofrontal and middle temporal gyri in children with IGE. Further analyses on main effects and interaction between group and frequency band suggested significant frequency-dependent changes in VMHC, and no significant interaction was found. The results were generally similar with global brain signal regression. Additional association analysis showed that VMHC in the putamen within the full and slow-4 bands was significantly positively correlated with chronological age in children with IGE, and the same analysis was non-significant in the controls; VMHC in the medial prefrontal region in the slow-4 band was significantly positively correlated with IQ performance sub-score. Our findings suggest that IGE children show frequency-dependent changes in interhemispheric integration that spans regions and systems involving cortical-subcortical, language, and visuomotor processing. Decreased functional coupling within the dorsal striatum may reflect atypical development in children with IGE.

[Broadband subharmonic active cavitation imaging with high cavitation to tissue ratio].

To improve the cavitation-to-tissue ratio (CTR) of cavitation imaging during the treatment with high-intensity focused ultrasound (HIFU), we proposed a pulse inversion based broadband subharmonic cavitation imaging method (PIBSHI). Due to the fact that the subharmonic signal is a unique nonlinear vibration characteristic of cavitation bubbles, we extracted the broadband subharmonic signal to get a high-CTR cavitation imaging. The simulation showed that the subharmonic signal produced by cavitating bubbles with different sizes varied, and the signal was stronger than other subharmonics when the bubbles' resonant frequency was close to 1/2 subharmonic frequency. Further experiment results demonstrated that compared with the conventional B-mode images, broadband subharmonic cavitation imaging (BSHI) has improved the CTR by 5.7 dB, and the CTR was further improved by 3.4 dB when combined with pulse inversion (PI) technology. Moreover, when the bandwidth was set to 100%~140% of the 1/2 subharmonic frequency in PIBSHI, the CTR was the highest and the imaging showed the optimal quality. The study may have reference value for the development of precise cavitation imaging during HIFU treatment, and contribute to improve the safety of HIFU treatment.

High mobility indium tin oxide thin film and its application at infrared wavelengths: model and experiment.

In this work, high mobility indium tin oxide (ITO) thin films with uniform crystallographic orientation are prepared. These films present a wide-range transmittance window and could be used as transparent electrodes at ultraviolet-visible-infrared wavelengths. In particular, the ITO thin film is characterized by low resistivity (5.1 × 10-4 Ωcm) and high infrared transmittance (88.5% at 2.5 µm) due to the improved mobility, achieving higher infrared performance than other transparent conductive materials. A model based on carrier's transport theory and Lorentz-Drude dielectric function is proposed to quantitatively calculate the optical performance of conductive thin films under the influence of plasma effect. The calculation demonstrates that ITO is a suitable electrode material for near/middle infrared optoelectronic applications.

GaN-based mid-power flip-chip light-emitting diode with high -3 dB bandwidth for visible light communications.

By directly flip-chip soldering three mid-power light-emitting diode (LED) chips with periodic micro-via-holes on ceramic substrates, -3 dB modulation bandwidths of 49.9 MHz, 58.8 MHz, and 25 MHz are obtained at the driving current of 170 mA. To the best of our knowledge, these are the reported highest -3 dB bandwidth values for flip-chip power-type LEDs (FC-LEDs) at the low-bias current levels. Moreover, good radiant powers are also achieved: 180.2 mW, 168.8 mW, and 233.8 mW at 150 mA, respectively. With a gold wire-free feature, the fabricated FC-LEDs could offer an opportunity to miniaturize the package volume of a LED module for illumination and free-space high-speed VLC dual-usage applications.

Study on the optimization of the deposition rate of planetary GaN-MOCVD films based on CFD simulation and the corresponding surface model.

Metal-organic chemical vapour deposition (MOCVD) is a key technique for fabricating GaN thin film structures for light-emitting and semiconductor laser diodes. Film uniformity is an important index to measure equipment performance and chip processes. This paper introduces a method to improve the quality of thin films by optimizing the rotation speed of different substrates of a model consisting of a planetary with seven 6-inch wafers for the planetary GaN-MOCVD. A numerical solution to the transient state at low pressure is obtained using computational fluid dynamics. To evaluate the role of the different zone speeds on the growth uniformity, single factor analysis is introduced. The results show that the growth rate and uniformity are strongly related to the rotational speed. Next, a response surface model was constructed by using the variables and the corresponding simulation results. The optimized combination of the matching of different speeds is also proposed as a useful reference for applications in industry, obtained by a response surface model and genetic algorithm with a balance between the growth rate and the growth uniformity. This method can save time, and the optimization can obtain the most uniform and highest thin film quality.