Predicting preoperative muscle invasion status for bladder cancer using computed tomography-based radiomics nomogram

OBJECTIVES

The aim of the study is to assess the efficacy of the established computed tomography (CT)-based radiomics nomogram combined with radiomics and clinical features for predicting muscle invasion status in bladder cancer (BCa).

METHODS

A retrospective analysis was conducted using data from patients who underwent CT urography at our institution between May 2018 and April 2023 with urothelial carcinoma of the bladder confirmed by postoperative histology. There were 196 patients enrolled in all, and each was randomized at random to either the training cohort (n = 137) or the test cohort (n = 59). Eight hundred fifty-one radiomics features in all were retrieved. For feature selection, the significance test and least absolute shrinkage and selection operator (LASSO) approaches were utilized. Subsequently, the radiomics score (Radscore) was obtained by applying linear weighting based on the selected features. The clinical and radiomics model, as well as radiomics-clinical nomogram were all established using logistic regression. Three models were evaluated using analysis of the receiver operating characteristic curve. An area under the curve (AUC) and 95% confidence intervals (CI) as well as specificity, sensitivity, accuracy, negative predictive value, and positive predictive value were included in the analysis. Radiomics-clinical nomogram's performance was assessed based on discrimination, calibration, and clinical utility.

RESULTS

After obtaining 851 radiomics features, 12 features were ultimately selected. Histopathological grading and tortuous blood vessels were included in the clinical model. The Radscore and clinical histopathology grading were among the final predictors in the unique nomogram. The three models had an AUC of 0.811 (95% CI, 0.742-0.880), 0.845 (95% CI, 0.781-0.908), and 0.896 (95% CI, 0.846-0.947) in the training cohort and in the test cohort they were 0.808 (95% CI, 0.703-0.913), 0.847 (95% CI, 0.739-0.954), and 0.887 (95% CI, 0.803-0.971). According to the DeLong test, the radiomics-clinical nomogram's AUC in the training cohort substantially differed from that of the clinical model (AUC: 0.896 versus 0.845, p = 0.015) and the radiomics model (AUC: 0.896 versus 0.811, p = 0.002). The Delong test in the test cohort revealed no significant difference among the three models.

CONCLUSIONS

CT-based radiomics-clinical nomogram can be a useful tool for quantitatively predicting the status of muscle invasion in BCa.

Quantitative MRI Analysis of Brachial Plexus and Limb-Girdle Muscles in Upper Extremity Onset Amyotrophic Lateral Sclerosis

BACKGROUND

Recent evidence highlights the potential of axonal degeneration as a biomarker for amyotrophic lateral sclerosis (ALS) detection. However, the diagnostic potential of peripheral nerve axon changes in ALS remains unclear.

PURPOSE

To evaluate the diagnostic performance of quantitative MRI of the brachial plexus and limb-girdle muscles (LGMs) in patients with upper extremity onset of ALS.

STUDY TYPE

Retrospective.

POPULATION

47 patients with upper extremity onset of ALS and 20 healthy volunteers.

FIELD STRENGTH/SEQUENCE

3-T, three-dimensional sampling perfection with application-optimized contrasts using different flip angle evolutions with short-tau inversion recovery sequences, T2-weighted turbo spin-echo Dixon sequence.

ASSESSMENT

The cross-sectional area (CSA) and nerve-muscle T2 signal intensity ratio (nT2) of the bilateral brachial plexus as well as the CSA and fat fraction (FF) of the bilateral LGMs were assessed by two radiologists. Disease severity and clinical stage of ALS patients were assessed by two neurologists.

STATISTICAL TESTS

Student's t-test, Wilcoxon rank-sum test, binary logistic regression, interclass correlation coefficient, receiver operating characteristic analysis, and correlation analysis were performed for MRI quantitative metrics and clinical variables. Significance level: P < 0.05.

RESULTS

In the affected limbs of patients with ALS, the CSA of the brachial plexus roots, trunks, and cords and the nT2 values of the brachial plexus trunks were significantly smaller than in the healthy controls. In the LGMs, the affected limbs of ALS showed significantly smaller CSA and higher FF than controls. The model containing parameters such as brachial plexus trunk CSA, subscapularis CSA, infraspinatus CSA, and subscapularis FF had excellent diagnostic efficacy for ALS. Additionally, increased subscapularis FF and supraspinatus FF were correlated with disease severity, and subscapularis CSA was negatively correlated with the clinical stage.

DATA CONCLUSION

Brachial plexus thinning, LGM atrophy, and fatty infiltration might serve as MRI-derived biomarkers for ALS with upper extremity onset.

LEVEL OF EVIDENCE

4 TECHNICAL EFFICACY: Stage 2.

Multi-Parametric Diffusion Tensor Imaging of The Optic Nerve for Detection of Dysthyroid Optic Neuropathy in Patients With Thyroid-Associated Ophthalmopathy

Objective

To evaluate the microstructural changes of the orbital optic nerve in thyroid-associated ophthalmopathy (TAO) patients with or without dysthyroid optic neuropathy (DON) using diffusion tensor imaging (DTI) and investigate whether DTI can be used to detect DON.

Materials and Methods

59 bilateral TAO patients with (n= 23) and without DON (non-DON, n= 36) who underwent pretreatment DTI were included and 118 orbits were analyzed. The clinical features of all patients were collected. DTI parameters, including mean, axial, and radial diffusivity (MD, AD, and RD, respectively) and fractional anisotropy (FA) of the intra-orbital optic nerve for each orbit were calculated and compared between the DON and non-DON groups. ROC curves were generated to evaluate the diagnostic performance of single or combined DTI parameters. Correlations between DTI parameters and ophthalmological characteristics were analyzed using correlation analysis.

Results

Compared with non-DON, the DON group showed decreased FA and increased MD, RD, and AD (P < 0.01). In the differentiation of DON from non-DON, the MD was optimal individually, and the combination of the four parameters had the best diagnostic performance. There were significant correlations between the optic nerve's four DTI metrics and the visual acuity and clinical active score (P < 0.05). In addition, optic nerve FA was significantly associated with the amplitude of visual evoked potentials (P = 0.022).

Conclusions

DTI is a promising technique in assessing microstructural changes of optic nerve in patients with DON, and it facilitates differentiation of DON from non-DON eyes in patients with TAO.

T2 Mapping with and without Fat-Suppression to Predict Treatment Response to Intravenous Glucocorticoid Therapy for Thyroid-Associated Ophthalmopathy

Objective

To evaluate the performance of baseline clinical characteristics and pretherapeutic histogram parameters derived from T2 mapping of the extraocular muscles (EOMs) in the prediction of treatment response to intravenous glucocorticoid (IVGC) therapy for active and moderate-to-severe thyroid-associated ophthalmopathy (TAO) and to investigate the effect of fat-suppression (FS) in T2 mapping in this prediction.

Materials and Methods

A total of 79 patients clinically diagnosed with active, moderate-to-severe TAO (47 female, 32 male; mean age ± standard deviation, 46.1 ± 10 years), including 43 patients with a total of 86 orbits in the responsive group and 36 patients with a total of 72 orbits in the unresponsive group, were enrolled. Baseline clinical characteristics and pretherapeutic histogram parameters derived from T2 mapping with FS (i.e., FS T2 mapping) or without FS (i.e., conventional T2 mapping) of EOMs were compared between the two groups. Independent predictors of treatment response to IVGC were identified using multivariable analysis. Receiver operating characteristic (ROC) curve analysis was performed to evaluate the predictive performance of the prediction models. Differences between the models were examined using the DeLong test.

Results

Compared to the unresponsive group, the responsive group had a shorter disease duration, lower kurtosis (FS-kurtosis), lower standard deviation, larger 75th, 90th, and 95th (FS-95th) T2 relaxation times in FS mapping and lower kurtosis in conventional T2 mapping. Multivariable analysis revealed that disease duration, FS-95th percentile, and FS-kurtosis were independent predictors of treatment response. The combined model, integrating all identified predictors, had an optimized area under the ROC curve of 0.797, 88.4% sensitivity, and 62.5% specificity, which were significantly superior to those of the imaging model (p = 0.013).

Conclusion

An integrated combination of disease duration, FS-95th percentile, and FS-kurtosis was a potential predictor of treatment response to IVGC in patients with active and moderate-to-severe TAO. FS T2 mapping was superior to conventional T2 mapping in terms of prediction.

Prediction of treatment response to intravenous glucocorticoid in patients with thyroid-associated ophthalmopathy using T2 mapping and T2 IDEAL

PURPOSE

To investigate the performance of combined T2 mapping and T2 iterative decomposition of water and fat with echo asymmetry and least-squares estimation (IDEAL) in orbital tissues to predict the therapeutic efficacy of intravenous glucocorticoids (IVGCs) for active and moderate-to-severe thyroid-associated ophthalmopathy (TAO).

METHOD

Sixty-three active and moderate-to-severe TAO patients (responsive group, n = 35; unresponsive group, n = 28) who underwent orbital MRI before receiving IVGCs were retrospectively enrolled. Baseline clinical characteristics and imaging parameters were analyzed and compared between the two groups of different therapeutic efficacy. Binary logistic regression analysis was conducted to determine the independent predictors, the predictive performance of which was evaluated using receiver operating characteristic curve analysis.

RESULTS

The mean T2 relaxation time of extraocular muscle (EOM-T2RT_mean) (P = 0.001), maximum T2RT of EOM (EOM-T2RT_max) (P = 0.001), mean water fraction of EOM (EOM-WF_mean) (P < 0.001), maximum WF of EOM (EOM-WF_max) (P < 0.001) and exophthalmos (P = 0.007) were significantly higher in the responsive group than in the unresponsive group. EOM-T2RT_mean (P < 0.001) and EOM-WF_max (P < 0.001) were determined as independent predictors for responsive patients with TAO in the multivariable analysis. Combining EOM-T2RT_mean ≥ 77.1 and EOM-WF_max ≥ 91.52 demonstrated optimal efficiency for prediction (area under the curve = 0.844) and optimal predictive sensitivity (77.1%). Setting EOM-WF_max ≥ 91.52 achieved the optimal predictive specificity (89.3%).

CONCLUSIONS

Pretherapeutic quantitative measurements, based on combining T2 mapping and T2 IDEAL in orbital tissues, are valuable for predicting IVGC treatment response in active and moderate-to-severe TAO. EOM-T2RT_mean and EOM-WF_max may become promising IVGC treatment response predictors.

The diagnostic value of the IDEAL-T2WI sequence in dysthyroid optic neuropathy: a quantitative analysis of the optic nerve and cerebrospinal fluid in the optic nerve sheath

OBJECTIVES

To evaluate the optic nerve and CSF in the optic nerve sheath as imaging markers of dysthyroid optic neuropathy (DON).

METHODS

In this single-centre retrospective study, orbital images of 30 consecutive participants (54 orbits) with DON, 30 patients (60 orbits) with thyroid-associated ophthalmopathy (TAO) without DON, and 19 healthy controls (HCs; 38 orbits) were analysed. The diameter and cross-sectional area of the optic nerve and its sheath, water fraction of the optic nerve, and volume of the fluid in the optic nerve sheath were measured and compared. The associations between MR parameters and clinical measures were assessed using correlation analysis.

RESULTS

The diameter and water fraction of the optic nerve (3 mm and 6 mm behind the eyeball), optic nerve subarachnoid space (ONSS) (3 mm and 6 mm behind the eyeball), and subarachnoid fluid volume in the optic nerve sheath were significantly greater in the DON group than in the TAO group (p < 0.01) or HC group (p < 0.01). ROC analysis showed that ONSS 3 mm behind the eyeball (ONSS3) was a robust predictor of DON (AUC = 0.957, sensitivity = 0.907, specificity = 0.9). Water fraction of the optic nerve 3 mm behind the eyeball (water fraction3) had the best specificity (0.967). Water fraction3, fluid volume in the optic nerve sheath, and optic nerve diameter (3 mm behind the eyeball) were correlated with clinical measures (i.e. clinical activity score, mean defect, and pattern standard deviation).

CONCLUSIONS

Increased water fraction of the optic nerve and ONSS3 are promising and easily accessible radiological markers for diagnosing DON.

KEY POINTS

• The water fraction of the optic nerve and optic nerve subarachnoid space (ONSS) are greater in patients with dysthyroid optic neuropathy (DON) than in patients with thyroid-associated ophthalmopathy (TAO) without DON. • The optic nerve and the cerebrospinal fluid in the optic nerve sheath measures are associated with visual dysfunction. • The water fraction of the optic nerve and ONSS may be promising imaging markers for diagnosing DON.

[Value of intravoxel incoherent motion diffusion weighted imaging in evaluating the microstructure changes in white matter hyperintensities]

Objective: To investigate the value of intravoxel incoherent motion diffusion weighted imaging (IVIM DWI) in evaluating microstructure changes in elderly white matter hyperintensities (WMH) patients and to analyze the correlation between IVIM parameters and severity grading and cognitive scores. Methods: Sixty-two WMH patients in Zhejiang Hospital were collected from December 2014 to March 2018 and underwent conventional magnetic resonance (MR) plain scan and diffusion weighted imaging with different b values. The age was 60-92(74±10) years with 37 males, 25 females. The severity of WMH was assessed by T(2) fluid attenuated inversion recovery (FLAIR) sequence and Fazekas score,which were divided into two subgroups. Slow diffusion coefficient (D), fast diffusion coefficient (D(*)) and perfusion fraction (f) from IVIM parameters of double exponential model were compared between regions of WMH (deep WMH (DWMH) and periventricular WMH (PWMH)) and surrounding normal white matter (NWM).The Shapiro-Wilk test was used for normality tests, Kruskal-Wallis tests and Dwass-Steel-Critchlow-Fligner (DSCF) procedure were used for the comparison among these parameters. Furthermore, Wilcoxon two-sample test was used for the comparisons between different severity. Pearson correlation analysis was performed to determine whether these D, D(*), f values were correlated with the mini mental state examination (MMSE) scores. Results: D(D)WMH (0.83(0.72,0.99)×10(-3) mm(2)/s), D(PWMH)((1.13±0.25)×10(-3) mm(2)/s) were significantly higher than D(NWM) ((0.71±0.05)×10(-3) mm(2)/s)(P<0.01). f (DWMH) ((8.94%(7.46%,11.67%)), f (PWMH)(8.34%(6.73%,9.96%)) were significantly higher than f (NWM)(6.71%±1.72%)(P<0.01).D in DWMH were significantly lower than that in PWMH(P<0.01), there's no statistically difference between other groups. D in severe WMH (both DWMH and PWMH) were significantly higher than that in mild WMH (P=0.000 1, P=0.04). Only f in PWMH were positively associated with the MMSE scores (r=0.326 5,P<0.05). Conclusions: IVIM DWI can noninvasively assess the variation of microstructure diffusion and perfusion in WMH in one sequence,which may objectively reflect the severity of these lesions. This method has important clinical significance for better assessment and management of this disease.

[Comparison of simple canalith repositioning treatment and medication therapeutic alliance in the management of canalithiasis associated with benign paroxysmal positional vertigo of the horizontal semicircular canal]

Objective:To compare the therapeutic efficacy and the recurrence rate between the simple repositioning method and the reposition manoeuvre plus medication in the treatment of horizontal semicircular canal otolith benign paroxysmal positional vertigo (HSC-BPPV). Method:Sixty-two patients diagnosed with otolith HSC-BPPV by roll maneuver test were randomly divided into canalith repositioning group (32 patients) and reposition plus drug treatment group (30 patients). Patients in the canalith repositioning group were treated only with Barbecue reposition maneuver; patients in the reposition plus drug treatment group were treated firstly with Barbecue reposition maneuver and then were given Alprostadil, Cinepazide and Betahistine drug treatment. Both groups were evaluated after 7 days and 28 days treatment, and the recurrence rate was analyzed after 3 months. Result:After 7 days of the treatment , the recovery rate of the two groups was 62.5% and 73.3%, respectively. There's no significant difference between the two groups. However, the total effective power of the reposition plus drug treatment group was 96.7%, which was significantly higher than that of the canalith repositioning group (75.0%) (χ²=5.858, P<0.05). There were 8 patients in the canalith repositioning group showed changes of BBPV types after treatment, while only 1 patient in the reposition plus drug treatment group showed lesion changes. The difference was statistically significant (χ²=4.061, P<0.05). After 28 days of the treatment, the recovery rate and the total effective power of the two groups was 100%, respectively. There is no statistical difference in the total effective rate between the two groups. After 3 months follow-up, 2 patients in the canalith repositioning group (6.25%) and in the reposition plus drug treatment group (6.67%) showed BBPV recurrence, and no significant difference in the recurrence rate was found between the two groups (P>0.05). Conclusion:The repositioning maneuver is the preferred method for treating HSC BPPV. Canalith reposition maneuver plus medication has no obvious effect on the recovery rate and the recurrence rate, it only increases the effective rate and reduces the changes of the BBPV types.

QSAR-based toxicity classification and prediction for single and mixed aromatic compounds

Quantitative structure-activity relationships (QSARs) based on the octanol/water partition coefficient were employed to predict acute toxicities of 36 substituted aromatic compounds and their mixtures. In this study, the model developed by Verhaar et al. was modified and used to calculate octano/water partition coefficients of chemical mixtures. To validate the model, acute toxicities of these chemicals were measured to Vibrio fischeri in terms of EC50. The results indicated that the obtained QSAR models could be used to predict toxicities of samples consi sting of these substituted aromatic compounds, individually or in combinations. The obtained equations were proved to be robust enough by using the leave-one-out test method. By classifying these chemicals into two groups, polar and non-polar, the toxicities of chemical mixtures within each group can be predicted accurately from their calculated partition coefficients.