Pitfalls in the management of subglottic paragangliomas at unusual location: a case report and literature review.

BACKGROUND: Subglottic paragangliomas (PGs) are exceptionally rare and unpredictable, occasionally presenting at an atypical location. There are three different clinical forms of subglottic PGs: intraluminal (tracheal PGs), extraluminal (thyroid PGs) and the mixed type (both intraluminal and extraluminal, mixed-subglottic PGs). These tumors are usually misdiagnosed as other relatively common primary thyroid or laryngotracheal tumors, and the treatment is troublesome. CASE PRESENTATION: A 22-year-old male patient with subglottic PGs has been successively misdiagnosed as thyroid tumors and subglottic hemangiomas, and lastly underwent local extended lumpectomy and laryngotracheal reconstruction with a pedicled thoracoacromial artery perforator flap (PTAPF). The patient was decannulated successfully after the second-stage tracheal reconstruction with a local flap, and no evidence of local recurrence and distant metastasis of the tumor until now. CONCLUSION: Subglottic PGs can be easily misdiagnosed as laryngotracheal or thyroid tumors when presented at an atypical location. It is essential for otolaryngologists and head and neck surgeons to remain vigilant against these tumors. If the tumor is not diagnosed or removed completely, patients may encounter a risk of lethal paroxysm, which is incredibly troublesome.

The role of readout-segmented echo-planar imaging-based diffusion-weighted imaging in evaluating tumor response of locally advanced rectal cancer after neoadjuvant chemoradiotherapy.

BACKGROUND: Accurate assessment of tumor response in rectal cancer could help individualize treatment. PURPOSE: To evaluate the role of diffusion-weighted imaging (DWI) based on readout-segmented echo-planar imaging (rs-EPI) in assessing tumor response after neoadjuvant chemoradiotherapy (CRT) in locally advanced rectal cancer (LARC). MATERIAL AND METHODS: Sixty-three patients with LARC who received neoadjuvant CRT and surgery were enrolled retrospectively. They all underwent pre- and post-CRT magnetic resonance examinations, including DWI using rs-EPI. According to pathological results, patients were grouped as pathological complete responder (pCR, n = 16) and non-pCR (n = 47). Visual assessment of residual tumor and whole-tumor histogram analysis of pre- and post-CRT apparent diffusion coefficient (ADC) map was performed by two radiologists; tumor volume on ADC map was also recorded. RESULTS: Overall inter-observer agreement was good for histogram analysis (ICC = 0.543-0.999). Tumor volume reduction rate on ADC map showed no significant difference between the two groups (P = 0.468). Post-CRT mean, quantile values, and their percentage changes were higher in the pCR group (all P < 0.001). Post-CRT mean value had a good diagnostic power in selecting pCR (AUC = 0.855), with a cut-off value of 1.345 × 10-3 mm2/s, yielding a sensitivity of 83%, specificity of 81.3%. Post-CRT 95% quantile value had the highest AUC (AUC = 0.868) among quantile values, and a higher specificity (87.5% vs. 81.3%) than mean value with comparable overall diagnostic performance (P = 0.563). Visual assessment showed a sensitivity of 85.1%, specificity of 68.8% in selecting pCR. CONCLUSION: Quantitative ADC value of rs-EPI DWI could reliably evaluate tumor response in patients with LARC. Post-CRT 95% quantile ADC value could help mean value to more accurately identify pCR.

[Application Value of CT Metal Artifact Correction Technology (MAC TM) in CT Review after Total Hip Replacement].

OBJECTIVE: To evaluate the application value of CT metal artifact correction technology (MAC TM) in CT review after total hip replacement. METHODS: A total of 72 patients who underwent CT re-examination after total hip replacement from December 2018 to March 2020 were enrolled, and the original data were reconstructed by filter backup projection （FBP） and MAC. Select three identical levels in the two sets of reconstructed images and place the same ROI. The selected levels were the initial level, central level, and lower edge of acetabulum. Measure the CT and noise (SD) of metal high and low density artifacts of the three levels area, as well as metal hip joint space, metal para-bone tissue, muscle, bladder and subcutaneous fat, and calculate the average value. Subcutaneous fat value was used as a reference to calculate the SNR and CNR of metal implant para-bone tissue, muscle and bladder. Two radiologists scored the two groups of reconstructed images using blinded method, Kappa's test was used to compare the homogeneity. RESULTS: There were differences between the two groups of reconstructed images in high- and low-density artifact areas, joint gap CT values, and image noise. Compared with the FBP group, the CT value of the high-density area and the joint space of the MAC group decreased, the CT value of the low-density area increased, and the noise value of each area decreased. The SNR and CNR of metal adjacent bone tissue, muscle and bladder were higher in the MAC group than those in the FBP group, and the difference was statistically significant ( P<0.05). The difference in subjective scores between the two groups was statistically significant ( Z=-6.564, P<0.05). 2 radiologists had moderate consistency with Kappa value of 0.72 on FBP group, and good consistency with Kappa value of 0.85 on MAC group. CONCLUSION: MAC TM in CT review after total hip replacement can reduce metal artifacts, make the joint space more clear, and improve the quality of CT images.

[Application Value of Motion-correction Phase Sensitive Inversion Recovery (MOCO-PSIR) to Evaluate Myocardial Fibrosis in Patients with Heart Failure Caused by Dilated Cardiomyopathy].

OBJECTIVE: To study the application value of motion-correction phase sensitive inversion recovery (MOCO-PSIR) to evaluate myocardial fibrosis in the patients with heart failure caused by dilated cardiomyopathy (DCM). METHODS: A prospective study included 60 patients who underwent cardiac MRI enhanced scan from June 2017 to November 2018, including 38 patients who were clinically diagnosed with DCM and 22 patients in the normal control group. All patients were scanned with three late gadolinium enhancement (LGE) sequences: segmented-PSIR, single-shot-PSIR, MOCO-PSIR at the same time. The subjective quality score (level 4) and image signal-to-noise ratio (objective evaluation) of normal and abnormal myocardium were analyzed and compared in three scanning technique groups. The detection rate of myocardial fibrosis and image acquisition time of the three scanning techniques were recorded. RESULTS: In the normal control group (sinus rhythm), subjective score showed no statistical significance. Subjective scoring results in the patients with DCM: MOCO-PSIR>single-shot-PSIR> segmented-PSIR (P < 0.05). SNR results PSIR-LGE images in DCM patients as well as control group: segmented-PSIR>MOCO-PSIR> single-shot-PSIR (P < 0.05). In the whole 646 segments analysis of DCM patients, the ratio unable to judge in segmented-PSIR was up to 25.5%, but only 1.4% in MOCO-PSIR. Significant difference was found in the three groups. While in the 374 segments of control group, no statistical difference was found in comparison of incapability to judge. Acquisition time covered left ventricular: (5.6±1.7) min in segmented-PSIR, (0.4±0.2) min in single-shot-PSIR and (4.5±1.1) min in MOCO-PSIR. Pairwise comparison of acquisition time among three scanning techniques was statistically significant (P < 0.001). CONCLUSION: MOCO-PSIR-LGE has better clinical significance than conventional delayed enhanced scan sequences in the diagnosis of myocardial fibrosis in the patients with heart failure caused by dilated cardiomyopathy.

Relationship between facet tropism and facet joint degeneration in the sub-axial cervical spine.

BACKGROUND: Facet tropism is the angular asymmetry between the left and right facet joint orientation. Although debatable, facet tropism was suggested to be associated with disc degeneration, facet degeneration and degenerative spondylolisthesis in the lumbar spine. The purpose of this study was to explore the relationship between facet tropism and facet degeneration in the sub-axial cervical spine. METHODS: A total of 200 patients with cervical spondylosis were retrospectively analyzed. Facet degeneration was categorized into 4 grade: grade I, normal; grade II, degenerative changes including joint space narrowing, cyst formation, small osteophytes (<3 mm) without joint hypertrophy; grade III, joint hypertrophy secondary to large osteophytes (>3 mm) without fusion of the joint; grade IV, bony fusion of the facet joints. Facet orientations and facet tropisms with respect to the transverse, sagittal and coronal plane were calculated from the reconstructed cervical spine, which was based on the axial CT scan images. The paired facet joints were then categorized into three types: symmetric, moderated tropism and severe tropism. Univariate and multivariate analysis were performed to evaluate the relationship between any demographic and anatomical factor and facet degeneration. RESULTS: The mean age of enrolled patients was 46.23 years old (ranging from 30 to 64 years old). There were 114 males and 86 females. The degrees of facet degeneration varied according to cervical levels and ages. Degenerated facet joints were most common at C2-C3 level and more common in patients above 50 years old. The facet orientations were also different from level to level. By univariate analysis, genders, ages, cervical levels, facet orientations and facet tropisms were all significantly different between the normal facets and degenerated facets. However, results from multivariate logistic regression suggested only age and facet tropism with respect to the sagittal plane were related to facet degeneration. CONCLUSION: Facet degeneration were more common at C2-C3 level. Older age and facet tropism with respect to the sagittal plane were associated with the facet degeneration.

Validation and Feasibility of Ultrafast Cervical Spine MRI Using a Deep Learning-Assisted 3D Iterative Image Enhancement System.

Purpose: This study aimed to evaluate the feasibility of ultrafast (2 min) cervical spine MRI protocol using a deep learning-assisted 3D iterative image enhancement (DL-3DIIE) system, compared to a conventional MRI protocol (6 min 14s). Patients and Methods: Fifty-one patients were recruited and underwent cervical spine MRI using conventional and ultrafast protocols. A DL-3DIIE system was applied to the ultrafast protocol to compensate for the spatial resolution and signal-to-noise ratio (SNR) of images. Two radiologists independently assessed and graded the quality of images from the dimensions of artifacts, boundary sharpness, visibility of lesions and overall image quality. We recorded the presence or absence of different pathologies. Moreover, we examined the interchangeability of the two protocols by computing the 95% confidence interval of the individual equivalence index, and also evaluated the inter-protocol intra-observer agreement using Cohen's weighted kappa. Results: Ultrafast-DL-3DIIE images were significantly better than conventional ones for artifacts and equivalent for other qualitative features. The number of cases with different kinds of pathologies was indistinguishable based on the MR images from ultrafast-DL-3DIIE and conventional protocols. With the exception of disc degeneration, the 95% confidence interval for the individual equivalence index across all variables did not surpass 5%, suggesting that the two protocols are interchangeable. The kappa values of these evaluations by the two radiologists ranged from 0.65 to 0.88, indicating good-to-excellent agreement. Conclusion: The DL-3DIIE system enables 67% spine MRI scan time reduction while obtaining at least equivalent image quality and diagnostic results compared to the conventional protocol, suggesting its potential for clinical utility.

Newly designed plate for the treatment of posterolateral tibial plateau fractures: a finite element analysis.

BACKGROUND: This study investigated the biomechanical properties of a new plate used for the treatment of posterolateral tibial plateau fractures using finite element analysis. METHODS: The study groups were as follows: group PM, model of the new plate with posteromedial tibial plateau fracture; group PL, model of the new plate with posterolateral tibial plateau fracture; and group PC, model of the new plate with posterior tibial plateau fracture. We used two loading modes: uniform loading on the entire plateau, and loading on the posterior plateau. Data such as the displacement of the fracture and distribution of stress on the new plate and screws were recorded and analyzed. RESULTS: When the whole plateau was loaded, the displacement of fractures in groups PM, PL, and PC were 0.273, 0.114, and 0.265 mm, respectively. The maximum stresses on the plates in groups PM, PL, and PC were 118.131 MPa, 44.191 MPa, and 115.433 MPa. The maximum stresses on the screws in Groups PM, PL, and PC were 166.731, 80.330, and 164.439 MPa, respectively. When the posterior tibial plateau was loaded, the displacement of the fractures in groups PM, PL, and PC was 0.410, 0.213, and 0.390 mm, respectively. The maximum stresses on the plates in groups PM, PL, and PC were 194.012 MPa, 72.806 MPa, and 185.535 MPa. The maximum stresses on the screws in Groups PM, PL, and PC were 278.265, 114.839, and 266.396 MPa, respectively. CONCLUSION: The results of this study revealed that titanium plates have good fixation effects in all groups; therefore, the use of the new plate for posterolateral tibial plateau fractures appears to be safe and valid.

Application of three-dimensional (3D) magnetic resonance (MR) Multi-Echo iN Steady-state Acquisition sequences in preoperative evaluation of lumbar disc herniation: a prospective study.

Background: Conventional spinal magnetic resonance imaging (MRI) cannot provide accurate diagnosis and surgical planning; thin-layer scanning can enhance the diagnostic efficacy. This study aimed to investigate the value of 3-dimensional (3D) magnetic resonance (MR) in preoperative evaluation of lumbar disc herniation, with a focus on the application of Multi-Echo iN Steady-state Acquisition (MENSA) sequence. Methods: A total of 51 patients who underwent lumbar disc herniation surgery in West China Hospital of Sichuan University from June 2021 to December 2021 were prospectively enrolled. A cross-sectional study was conducted on those patients. The Cube group was scanned using 3D-FSE-Cube sequence, the Cube stir group was scanned using 3D-FSE-Cube Short Tau Inversion Recovery (STIR) sequence, and the MENSA group was scanned using MENSA sequence. Signal and noise values of nerve, herniated disc, ligamentum flavum (LF), and soft tissue were measured on the 3 groups. Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were calculated. Objective scores were calculated by analysis of variance (ANOVA). Image quality was scored by a 5-point method. Friedman test was used to compare subjective scores, and Kappa test was used to evaluate the consistency of 2 readers' scores. Results: The nerve root SNRs in the MENSA and Cube stir groups were higher than that in the Cube group (P<0.01), but there was no substantial statistical difference between the 2 groups. The herniated disc and LF SNRs of the MENSA group were greater than those of the Cube stir and Cube groups (P<0.01). Soft tissue SNR was greater in the MENSA group compared with the Cube stir group (P<0.01), which was greater than the SNR in the Cube group (P<0.01). The nerve root CNR of the Cube group (102.88±73.19) was greater than that of the MENSA group (55.98±25.26, P<0.01), which was higher than the CNR in the Cube Stir group (29.42±16.22, P<0.01). The herniated disc CNR was higher in the MENSA and Cube groups than that in the Cube Stir group. The CNR of LF was greater in the MENSA group (37.71±16.87) compared to the Cube group (29.76±25.73, P=0.03), which was greater than that in the Cube stir group (10.50±7.75, P<0.01). Among the subjective ratings of 2 reviewers, MENSA sequence scored highest in the qualitative measures of image quality. In the consistency test, the Kappa values of 2 readers for 3 groups of images were all greater than 0.73, indicating good consistency. The differences of subjective scores among all groups were statistically significant (P<0.05). Overall, it was indicated that the consistency test results of the 2 readers were statistically significant and consistent. The MENSA group had the highest accuracy in diagnosing nerve compression. In addition, MENSA sequence ranked highest among the 3 sequences with 94.1% diagnostic accuracy. Conclusions: The preoperative 3D MRI MENSA sequence can clearly depict the nerve roots and offer desirable contrast between the nerve roots, LF, bone, and intervertebral discs (IVDs). Patients with lumbar degeneration can effectively benefit from MENSA sequence since it provides useful imaging information to help understand disc herniation and compression of adjacent tissues when developing preoperative surgical strategies.

[Image quality adapted thoracic diameters in CT coronary artery imaging].

OBJECTIVE: To evaluate the correlation between image quality and thoracic diameters, anteroposterior diameter (AP) and right-left diameter (RL) for the optimization of reducing radiation dose in coronary artery imaging with Dual-source CT. METHODS: 118 patients underwent CT coronary artery imaging (CTCA) were divided into two groups (A and B) according to body mass index (BMI). There were 58 patients in group A with BMI values > or = 25 kg/m2 and < 30 kg/m2; and 60 patients in group B with BMI values < 25 kg/m2. Scan parameters: collimation 64 X 0.6 mm, reconstruction slice thickness 0.75 mm, reconstructin interval 0.7 mm, FOV 150-180 mm, the pitch adjusted according to heart rate automatically. CT imagings were obtained with tube voltage 100 kV, tube current 330 mAs (group A) and 100 kV, tube current 220 mAs (group B). The contrast-noise ratio (CNR), signal to noise ratio (SNR), as well as blind correlation test score values were calculated to establish the relationship among BMI, AP, RL and CNR, SNR. RESULTS: RL of five levels in groups of A, B were correlated to CNRa (P < 0.05). In group A and B (except iii, iv level of Group A), AP were associated with CNRa (P < 0.05). In addition to ii, iv level of group A, v level of group B, BMI were associated with CNRa (P < 0.05). The correlation coefficient of CNRa and RL of group A except ii level was greater than that of CNRa and AP. The correlation coefficient of CNRa, SNRa and RL of group B was greater than that of CNRa, SNRa and AP. Except iii level, the correlation coefficient of CNRa, SNRa and AP of group A was greater than that of CNRa, SNRa and BMI. Except ii level, the correlation coefficient of CNRa and AP of group B was greater than that of CNRa and BMI. CONCLUSION: Thoracic diameter of RL can be used as a guider to select the appropriate scan protocol in the coronary imaging acqusition with dual-source CT.

Proximal fibular axis is a reliable landmark for tibial coronal alignment in patients with or without knee osteoarthritis: A radiological comparative study.

BACKGROUND: Proper coronal alignment of the limb is of vital importance in the progression of knee osteoarthritis even in the long-term survivorship of component after total knee arthroplasty (TKA). Nevertheless, to the best of our knowledge, the relationship between coronal fibular axis and tibial mechanical axis had not reached a consensus in the literatures available. The current study aimed to explore the anatomic relationship between tibia and fibula alignment. METHODS: A total of 100 patients with knee osteoarthritis scheduled for total knee arthroplasty were enrolled in this study (Group A), and radiographic measurement was compared to a control group of 100 healthy volunteers without knee osteoarthritis (Group B). Full-length standing hip-to-ankle radiographs were used to assess limb alignment. The angle between coronal proximal fibular anatomic axis and tibia mechanical axis (PFTA) was used to represent the anatomic relationship between tibia and fibula alignment. A negative value indicates fibula varus relative to tibia mechanical axis, while a positive value indicates fibula valgus. RESULTS: The mean PFTAs were -0.9° ± 0.9° and -1.0° ± 0.8° in Groups A and B. There was no significant difference between the two groups. No significant difference was detected in PFTA distribution in the group A and B. When the mean value of PFTA is used as baseline data, the percentage of subjects in which the PFTA deviation was within 0.5°, 1°, and 1.5° was 51%, 84%, and 94% in Group A and 53%, 87%, and 96% in Group B. There was also no significant difference in distribution deviation between the two groups. No patient-specific factors were correlated with the PFTA. CONCLUSIONS: The proximal fibular anatomic axis is a reliable landmark for tibial mechanical axis in the coronal plane in patients with or without knee osteoarthritis.

[The value of split-bolus 2-phase with virtual non-enhanced scan in CT urography].

OBJECTIVE: To investigate the value of split-bolus 2-phase with virtual non-enhanced scan in CT urography. METHODS: Eighty (80) patients with urinary obstruction were divided into two groups, group A was traditional CT urography scan, group B was split-bolus 2-phase with virtual non-enhanced scan. The scan sequence of group A included conventional scan first, then enhanced scan in arterial phase, parenchyma phase and excretion delayed phase after the injection of 100 mL contrast agent. The scan sequence of group B included conventional scan and enhanced scan following two bolus injection of contrast; the first injection of contrast was 40 mL, the second injection was 60 mL with 15-30 minutes delay, then enhanced scan was conducted in arterial and parenchymal phase, the parenchymal phase scan was performed with dual energy scanning sequence. The image quality of urinary collecting system, the detection of urinary obstructive lesion, and radiation dose were compared between the two groups. RESULTS: Between the two imaging methods, the imaging quality of urinary system did not show significant difference, but radiation dose was statistically significant difference. The radiation dose of split-bolus 2-phase with virtual non-enhanced scan was only 55% of traditional CTU scan. CONCLUSION: Split-bolus2 phase with virtual non-enhanced scan could obtain the same image quality as tranditional CTU, while reducing the approximately half the radiation dose.

Prognostic value of computed tomography derived skeletal muscle mass index in lung cancer: A meta-analysis.

BACKGROUND: The prognostic role of the skeletal muscle mass index (SMI) derived from computed tomography (CT) imaging been well verified in several types of cancers. However, whether the SMI could serve as a reliable and valuable predictor of long-term survival in lung cancer patients remains unclear. AIM: To identify the prognostic value of the CT-derived SMI in lung cancer patients. METHODS: The PubMed, Web of Science, and Embase electronic databases were searched up to November 5, 2021 for relevant studies. The Reference Citation Analysis databases were used during the literature searching and selection. Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated to assess the association of the SMI with the overall survival (OS) of lung cancer patients. All statistical analyses were performed with STATA 12.0 software. RESULTS: A total of 12 studies involving 3002 patients were included. The pooled results demonstrated that a lower SMI was significantly related to poorer OS (HR = 1.23, 95%CI: 1.11-1.37, P < 0.001). In addition, the subgroup analyses stratified by treatment (nonsurgery vs surgery), tumor stage (advanced stage vs early stage), and tumor type (non-small cell lung cancer vs lung cancer) showed similar results. CONCLUSION: The CT-derived SMI is a novel and valuable prognostic indicator in lung cancer and might contribute to the clinical management and treatment of lung cancer patients.

Preoperative Computed Tomography Radiomics Analysis for Predicting Receptors Status and Ki-67 Levels in Breast Cancer.

BACKGROUND: To assess the prediction performance of preoperative chest computed tomography (CT) based radiomics features for estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor-2 (HER2+), and Ki-67 status of breast cancer. MATERIALS AND METHODS: This study enrolled 108 breast cancer patients who received preoperative chest CT examinations in our institution from July 2018 to January 2020. Radiomics features were separately extracted from nonenhanced, arterial, and portal-venous phases CT images. The least absolute shrinkage and selection operator logistic regression was used for feature selection. Then the radiomics signatures for each phase and a combined model of 3 phases were built. Finally, the receiver operating characteristic curves and calibration curves were used to confirm the performance of the radiomics signatures and combined model. In addition, the decision curves were performed to estimate the clinical usefulness of the combined model. RESULTS: The 20 most predictive features were finally selected to build radiomics signatures for each phase. The combined model achieved the overall best performance than using either of the nonenhanced, arterial and portal-venous phases alone, achieving an area under the receiver operating characteristic curve of 0.870 for ER+ versus ER-, 0.797 for PR+ versus PR-, 0.881 for HER2+ versus HER2-, and 0.726 for Ki-67. The decision curve demonstrated that the CT-based radiomics features were clinically useful. CONCLUSION: This study indicated preopreative chest CT radiomics analysis might be able to assess ER, PR, HER2+, and Ki-67 status of breast cancer. The findings need further to be verified in future larger studies.

The application of three-dimensional printed patient-specific drilling templates for expansive open-door laminoplasty: A single-center, prospective randomized controlled study.

Background: The choice of trough position in Expansive open-door laminoplasty (EOLP) mostly relied on bony landmarks and surgeons' experience. The present study was to validate the efficacy of the three-dimensional (3D) printed patient-specific drilling templates with the function of locating and depth control for EOLP. Materials and Methods: A single-center, prospective randomized controlled study was conducted on the patients who underwent unilateral EOLP from August 2019 to December 2020. The 3D printed patient-specific drilling template was fabricated and used in the template group. All the EOLP were performed by a senior surgeon and a junior surgeon. The clinical outcomes and radiographic results were evaluated. Results: A total of 37 patients who completed the 12-month follow-up were analyzed. The clinical outcomes were significantly improved after surgery in both groups (P < 0.05). The visual analogue scale (VAS) scores were significantly lower in the template group at 12 months postoperatively (P < 0.05). The anteroposterior diameter, Pavlov's ratio and Open angle were all higher in the template group than those in the control group at 3 days and 12 months postoperatively (P < 0.05). The satisfaction of the trough position on both sides and incomplete fracture rate on the hinge side were higher in the template group based on the CT scans taken 3 days after surgery (P < 0.05). To the junior surgeon, the satisfaction and the incomplete fracture rate were significantly higher in the template group compared with those in the control group (P < 0.05). Conclusion: The application of 3D printed patient-specific drilling templates with the function of locating and depth control for EOLP could improve the outcome of neck pain relief and expand the decompression. It can also improve the satisfaction of the trough position on the open-door side and the hinge side and decrease the complete fracture rate on the hinge side, especially for the junior surgeon.

Accelerated 3D high-resolution T2-weighted breast MRI with deep learning constrained compressed sensing, comparison with conventional T2-weighted sequence on 3.0 T.

PURPOSE: To evaluate the feasibility of isotropic 3D high-resolution T2-weighted imaging (T2WI) MRI sequences and compare the images reconstructed by integrating artificial intelligence-compressed sensing (AI-CS), compressed sensing (CS), and conventional 2D T2WI sequences for quality. MATERIALS AND METHODS: Fifty-two female patients (ages: 26-80 years) with suspected breast cancer were enrolled. They underwent breast MRI examinations using three sequences: conventional T2WI, CS 3D T2WI, and AI-CS 3D T2WI. Image quality, signal-to-noise ratio (SNR), contrast-to-noise ratio, tumor volume, and maximal tumor diameter were compared using the Friedman test. Image quality was scored on a 5-point scale, with 1 indicating nonassessable quality and 5 indicating excellent quality. Tumor volume and maximal tumor diameter were compared based on AI-CS 3D T2WI (slightly high signal), conventional T2WI, and dynamic contrast-enhanced (DCE) sequences. RESULTS: All three T2WI were successfully performed in all patients. 3D CS and AI-CS were significantly better than conventional T2WI in terms of lesion conspicuity and morphology, structural details, overall image quality, diagnostic information for breast lesions, and breast tissue delineation (P < 0.001). The SNR of conventional T2WI was significantly higher for 3D T2WI sequences. The contrast-to-noise ratio was significantly higher for AI-CS 3D T2WI than for conventional T2WI sequence. There was no significant difference in tumor volume between DCE (8.08 ± 16.51) and AI-CS 3D T2WI (8.25 ± 16.29) sequences and no significant differences in tumor diameter among DCE, AI-CS 3D T2WI, and conventional T2WI sequences. CONCLUSION: Isotropic-resolution 3D T2WI sequences can be acquired using AI-CS while maintaining image quality and diagnostic value, which may pave the way for isotropic 3D high-resolution T2WI for clinical application.

Effect of Epidural Dexmedetomidine as an Adjuvant to Local Anesthetics for Labor Analgesia: A Meta-Analysis of Randomized Controlled Trials.

BACKGROUND: This study aims to determine the analgesic effect and safety of dexmedetomidine as an adjuvant to epidural local anesthetics during labor. METHODS: Randomized controlled trials comparing epidural blocks with or without dexmedetomidine for labor analgesia were comprehensively searched. Review manager 5.4 was used to analyze the extracted data. RESULTS: Compared with placebo and opioids, dexmedetomidine relieved labor pain of 15 min (P=0.002), 30 min (P=0.01), and 120 min (P=0.02) after block and at the moment of fetal disengagement (P=0.0002), decreased mean arterial pressure of 120 min (P=0.01), heart rate of 30 min (P=0.003), 60 min (P < 0.00001), and 120 min (P < 0.00001) after block, blood loss (P=0.02), and the incidence of nausea/vomiting (P=0.006), and increased the incidence of maternal bradycardia (P=0.04). However, sensitivity analysis only found that the incidence of nausea/vomiting was significantly different. Compared with placebo, dexmedetomidine relieved labor pain of 30 min after block (P < 0.00001) and did not increase the incidences of side effects, but only two studies were enrolled. Compared with opioids, dexmedetomidine decreased the incidence of nausea/vomiting (P=0.002), increased the incidence of maternal bradycardia (P=0.04), and had a similar effect on labor pain relief; however, sensitivity analysis found that significant difference existed only at the incidence of nausea/vomiting. Other outcomes from meta-analysis or subgroup analysis were not different. CONCLUSIONS: Epidural dexmedetomidine has the potential to offer a better analgesic effect than placebo, similar labor pain control to opioids, and has no definite adverse effects on the parturient or fetus, but more high-quality studies are needed to confirm these conclusions.

Prognostic value of ground glass opacity on computed tomography in pathological stage I pulmonary adenocarcinoma: A meta-analysis.

BACKGROUND: The clinical role of ground glass opacity (GGO) on computed tomography (CT) in stage I pulmonary adenocarcinoma patients currently remains unclear. AIM: To explore the prognostic value of GGO on CT in lung adenocarcinoma patients who were pathologically diagnosed with tumor-node-metastasis stage I. METHODS: A comprehensive and systematic search was conducted through the PubMed, EMBASE and Web of Science databases up to April 3, 2021. The hazard ratio (HR) and corresponding 95% confidence interval (CI) were combined to assess the association between the presence of GGO and prognosis, representing overall survival and disease-free survival. Subgroup analysis based on the ratio of GGO was also conducted. STATA 12.0 software was used for statistical analysis. RESULTS: A total of 12 studies involving 4467 patients were included. The pooled results indicated that the GGO predicted favorable overall survival (HR = 0.44, 95%CI: 0.34-0.59, P < 0.001) and disease-free survival (HR = 0.35, 95%CI: 0.18-0.70, P = 0.003). Subgroup analysis based on the ratio of GGO further demonstrated that the proportion of GGO was a good prognostic indicator in pathological stage I pulmonary adenocarcinoma patients, and patients with a higher ratio of GGO showed better prognosis than patients with a lower GGO ratio did. CONCLUSION: This meta-analysis manifested that the presence of GGO on CT predicted favorable prognosis in tumor-node-metastasis stage I lung adenocarcinoma. Patients with a higher GGO ratio were more likely to have a better prognosis than patients with a lower GGO ratio.

Lower Tibial Tunnel Placement in Isolated Posterior Cruciate Ligament Reconstruction: Clinical Outcomes and Quantitative Radiological Analysis of the Killer Turn.

BACKGROUND: The "killer turn" effect after posterior cruciate ligament (PCL) reconstruction is a problem that can lead to graft laxity or failure. Solutions for this situation are currently lacking. PURPOSE: To evaluate the clinical outcomes of a modified procedure for PCL reconstruction and quantify the killer turn using 3-dimensional (3D) computed tomography (CT). STUDY DESIGN: Case series; Level of evidence, 4. METHODS: A total of 15 patients underwent modified PCL reconstruction with the tibial aperture below the center of the PCL footprint. Next, 2 virtual tibial tunnels with anatomic and proximal tibial apertures were created on 3D CT. All patients were assessed according to the Lysholm score, International Knee Documentation Committee (IKDC) Subjective Knee Evaluation Form, Tegner score, side-to-side difference (SSD) in tibial posterior translation using stress radiography, and 3D gait analysis. RESULTS: The modified tibial tunnel showed 2 significantly gentler turns (superior, 109.87° ± 10.12°; inferior, 151.25° ± 9.07°) compared with those reconstructed with anatomic (91.33° ± 7.28°; P < .001 for both comparisons) and proximal (99° ± 7.92°; P = .023 and P < .001, respectively) tibial apertures. The distance from the footprint to the tibial aperture was 16.49 ± 3.73 mm. All patient-reported outcome scores (mean ± SD) improved from pre- to postoperatively: Lysholm score, from 46.4 ± 18.87 to 83.47 ± 10.54 (P < .001); Tegner score, from 2.47 ± 1.85 to 6.07 ± 1.58 (P < .001); IKDC sports activities score, from 19 ± 9.90 to 33.07 ± 5.35 (P < .001); and IKDC knee symptoms score, from 17.87 ± 6.31 to 25.67 ± 3.66 (P < .001). The mean SSD improved from 9.15 ± 2.27 mm preoperatively to 4.20 ± 2.31 mm postoperatively (P < .001). The reconstructed knee showed significantly more adduction (by 1.642°), less flexion (by 1.285°), and more lateral translation (by 0.279 mm) than that of the intact knee (P < .001 for all). CONCLUSION: Lowering the tibial aperture during PCL reconstruction reduced the killer turn, and the clinical outcomes remained satisfactory. However, SSD and clinical outcomes were similar to those of previously described techniques using an anatomic tibial tunnel.

Patient-Specific or Conventional Instrumentations: A Meta-analysis of Randomized Controlled Trials.

OBJECTIVE: To conduct a meta-analysis of randomized controlled trials (RCTs) to compare knee arthroplasty with patient-specific instrumentation (PSI) with the conventional instrumentation (CI). METHODS: RCTs were selected in PubMed and Embase from 2012 to 2018. Key data extracted included malalignment of mechanical axis, blood loss, surgical time, Oxford Knee Score (OKS), Knee Society Score (KSS), length of stay, and complications. Subgroup analysis was also performed regarding different PSI systems and different image processing methods. RESULTS: 29 RCTs with 2487 knees were eligible for the meta-analysis. Results showed that PSI did not improve the alignment of the mechanical axis compared with CI, but MRI-based PSI and Visionaire-specific PSI decrease the risk of malalignment significantly (P = 0.04 and P = 0.04 and P = 0.04 and P = 0.04 and P = 0.04 and. CONCLUSION: PSI reduced the blood loss and improved KSS. MRI-based PSI reduced operative time and risk of malalignment of mechanical axis compared with CT-based PSI. Moreover, Visionaire-specific PSI achieves better alignment result of the mechanical axis than other systems.

Gadoxetic acid-enhanced MRI radiomics signature: prediction of clinical outcome in hepatocellular carcinoma after surgical resection.

BACKGROUND: This study aimed to evaluate the efficiency of gadoxetic acid-enhanced MRI-based radiomics features for prediction of overall survival (OS) in hepatocellular carcinoma (HCC) patients after surgical resection. METHODS: This prospective study approved by the Institutional Review Board enrolled 120 patients with pathologically confirmed HCC. Radiomics signatures (rad-scores) were built from radiomics features in 3 different regions of interest (ROIs) with the least absolute shrinkage and selection operator (LASSO) cox regression analysis. Preoperative clinical characteristics and semantic imaging features potentially associated with patient survival were evaluated to develop a clinic-radiological model. The radiomics features and clinic-radiological predictors were integrated into a joint model using multivariable Cox regression analysis. Kaplan-Meier analysis and log-rank tests were performed to compare the discriminative performance and evaluated on the validation cohort. RESULTS: The radiomics signatures showed a significant association with patient survival in both cohorts (all P<0.001). The BCLC (Barcelona clinic liver cancer) stage, non-smooth tumor margin, and the combined rad-score were independently associated with OS. Moreover, the combined model incorporating with clinic-radiological and radiomics features showed an improved predictive performance with C-index of 0.92 [95% confidence interval (CI): 0.87-0.97], compared to the clinic-radiological model (C-index, 0.86, 95% CI: 0.79-0.94; P=0.039) or the combined rad-score (C-index, 0.88, 95% CI: 0.81-0.95; P=0.016). CONCLUSIONS: Radiomics features along with clinic-radiological predictors can efficiently aid in preoperative HCC prognosis prediction after surgical resection and enable a step forward precise medicine.