A no-Reference Stereoscopic Image Quality Assessment Network Based on Binocular Interaction and Fusion Mechanisms.

In contemporary society full of stereoscopic images, how to assess visual quality of 3D images has attracted an increasing attention in field of Stereoscopic Image Quality Assessment (SIQA). Compared with 2D-IQA, SIQA is more challenging because some complicated features of Human Visual System (HVS), such as binocular interaction and binocular fusion, must be considered. In this paper, considering both binocular interaction and fusion mechanisms of the HVS, a hierarchical no-reference stereoscopic image quality assessment network (StereoIF-Net) is proposed to simulate the whole quality perception of 3D visual signals in human cortex, including two key modules: BIM and BFM. In particular, Binocular Interaction Modules (BIMs) are constructed to simulate binocular interaction in V2-V5 visual cortex regions, in which a novel cross convolution is designed to explore the interaction details in each region. In the BIMs, different output channel numbers are designed to imitate various receptive fields in V2-V5. Furthermore, a Binocular Fusion Module (BFM) with automatic learned weights is proposed to model binocular fusion of the HVS in higher cortex layers. The verification experiments are conducted on the LIVE 3D, IVC and Waterloo-IVC SIQA databases and three indices including PLCC, SROCC and RMSE are employed to evaluate the assessment consistency between StereoIF-Net and the HVS. The proposed StereoIF-Net achieves almost the best results compared with advanced SIQA methods. Specifically, the metric values on LIVE 3D, IVC and WIVC-I are the best, and are the second-best on the WIVC-II.

The pelvic radius technique in the assessment of spinopelvic sagittal alignment of degenerative spondylolisthesis and lumbar spinal stenosis.

BACKGROUND: Degenerative spondylolisthesis (DS) and lumbar spinal stenosis (LSS) are the most common degenerative spinal diseases. The evaluating of spinopelvic sagittal alignment of the two diseases using pelvic radius (PR) technique have not been reported. The purpose of this study was to use PR measurement technique to compare the differences in spinopelvic sagittal alignment between DS and LSS. METHODS: A total of 145 patients with DS or LSS were retrospectively reviewed. Seventy patients with DS (DS group) and 75 age-matched patients with LSS (LSS group) were enrolled. Spinopelvic parameters including pelvic angle (PA), regional lumbopelvic lordosis (PR-L1, PR-L2, PR-L3, PR-L4 and PR-L5), total lumbopelvic lordosis (PR-T12), pelvic morphology (PR-S1), sagittal vertical axis from the C7 plumb line (SVA), lumbar lordosis (LL), thoracic kyphosis (TK), L4 slope and L5 slope were assessed in the two groups. Several parameters of DS and LSS group were compared with the normal population (NP). RESULTS: The PR-L4, PR-L5 and PR-S1 in the DS group were significantly smaller than those in the LSS group. There was no difference in PR-T12 between the DS group and NP (p > 0.05), while PR-T12 of the LSS group were significantly lower (p < 0.01). Degree of correlations among spinopelvic parameters differed between the two groups. PR-T12 of the DS group was more strongly correlated with PA (r = -0.829, p < 0.001) than with LL (r = 0.664, p < 0.001), TK (r = 0.582, p < 0.001). PR-T12 of the LSS group was more strongly correlated with LL (r = 0.854, p < 0.001), TK (r = 0.616, p < 0.001) than with PA (r = -0.582, p < 0.001). CONCLUSIONS: PR-L4 and PR-L5 may be the predisposing factors for DS development. Spinopelvic morphology differed in patients with DS and LSS compared to NP. The compensatory mechanisms to maintain spinopelvic sagittal alignment in DS and LSS patients may be different.

Sequencing-based detection of drug-resistant Mycobacterium tuberculosis in patients with spinal tuberculosis.

INTRODUCTION: Traditionally, bacterial cultures serve as the gold standard for the detection of drug resistance and can provide evidence for directing the treatment of tuberculosis. However, this method has a low positive rate and is time consuming, which significantly limits its wide application. Thus, in the present study, the genes associated with drug resistance were amplified and sequenced to determine the presence of drug-resistant mutations in Mycobacterium tuberculosis. In addition, to find a more sensitive, specific, rapid, and simple method for the detection of drug-resistant bacteria, this method was compared with traditional bacterial culture. MATERIALS AND METHODS: Pus was collected from surgical patients with spinal tuberculosis. The common drug resistance genes (rpoB, rpsL, and katG) were amplified by PCR. The PCR products were then sequenced, and the sequences were compared with those in the NCBI database using DNATools v.5.1 software. RESULTS: Mutations were identified in 17 patients, including mutations in the rpsL gene in four patients, the rpoB gene in seven, and the katG gene in six. The mean time of detection was 6 days. CONCLUSION: These results indicated that PCR and DNA sequencing are rapid, sensitive, and specific methods for the detection of drug-resistant genes of M. tuberculosis in patients with spinal tuberculosis. This method may provide critical evidence for the clinical treatment of tuberculosis when it is applied in combination with bacterial culture.

Detection of Mycobacterium tuberculosis DNA in the sclerotic spinal wall.

Recent studies have shown that the major spinal lesion in spinal tuberculosis is predominantly sclerotic and accounts for >70% of the lesion. In this type of sclerosis, apart from spinal reactive hyperplasia and increased bone density, the most severe lesion is the formation of a hard outer osteoid shell (the sclerotic wall) around the cheese-like substances and granulated tissues. In the current study, polymerase chain reaction detection of Mycobacterium tuberculosis in the sclerotic wall was performed. Surgical specimens were obtained from 18 patients with spinal tuberculosis with peripheral sclerotic wall (as shown by computed tomography) and included the sclerotic wall, subnormal bone tissue outside the sclerotic wall, and iliac bone tissue (control). The IS986 gene in the samples was amplified by polymerase chain reaction followed by DNA sequencing. The obtained sequences were then compared with the published sequences in GenBank using DNATools version 5.1 software (International Centre for Genetic Engineering and Biotechnology, Trieste, Italy). The polymerase chain reaction results showed that 16 specimens from the sclerotic spinal wall, 3 from the subnormal bone, and 0 from the controls were positive for M tuberculosis, indicating a statistically significant difference (P<.05). These results indicated that M tuberculosis was present in the spinal sclerotic wall. Combined with our previous studies, we conclude that the sclerotic wall should be considered a lesion in patients with spinal tuberculosis.