Characterization of renal masses with MRI-based radiomics: assessment of inter-package and inter-observer reproducibility in a prospective pilot study

OBJECTIVES

To evaluate radiomics features' reproducibility using inter-package/inter-observer measurement analysis in renal masses (RMs) based on MRI and to employ machine learning (ML) models for RM characterization.

METHODS

32 Patients (23M/9F; age 61.8 ± 10.6 years) with RMs (25 renal cell carcinomas (RCC)/7 benign masses; mean size, 3.43 ± 1.73 cm) undergoing resection were prospectively recruited. All patients underwent 1.5 T MRI with T2-weighted (T2-WI), diffusion-weighted (DWI)/apparent diffusion coefficient (ADC), and pre-/post-contrast-enhanced T1-weighted imaging (T1-WI). RMs were manually segmented using volume of interest (VOI) on T2-WI, DWI/ADC, and T1-WI pre-/post-contrast imaging (1-min, 3-min post-injection) by two independent observers using two radiomics software packages for inter-package and inter-observer assessments of shape/histogram/texture features common to both packages (104 features; n = 26 patients). Intra-class correlation coefficients (ICCs) were calculated to assess inter-observer and inter-package reproducibility of radiomics measurements [good (ICC ≥ 0.8)/moderate (ICC = 0.5-0.8)/poor (ICC < 0.5)]. ML models were employed using reproducible features (between observers and packages, ICC > 0.8) to distinguish RCC from benign RM.

RESULTS

Inter-package comparisons demonstrated that radiomics features from T1-WI-post-contrast had the highest proportion of good/moderate ICCs (54.8-58.6% for T1-WI-1 min), while most features extracted from T2-WI, T1-WI-pre-contrast, and ADC exhibited poor ICCs. Inter-observer comparisons found that radiomics measurements from T1-WI pre/post-contrast and T2-WI had the greatest proportion of features with good/moderate ICCs (95.3-99.1% T1-WI-post-contrast 1-min), while ADC measurements yielded mostly poor ICCs. ML models generated an AUC of 0.71 [95% confidence interval = 0.67-0.75] for diagnosis of RCC vs. benign RM.

CONCLUSION

Radiomics features extracted from T1-WI-post-contrast demonstrated greater inter-package and inter-observer reproducibility compared to ADC, with fair accuracy for distinguishing RCC from benign RM.

CLINICAL RELEVANCE

Knowledge of reproducibility of MRI radiomics features obtained on renal masses will aid in future study design and may enhance the diagnostic utility of radiomics models for renal mass characterization.

Performance of native and gadoxetate-enhanced liver and spleen T1 mapping for noninvasive diagnosis of clinically significant portal hypertension: preliminary results

PURPOSE

In this preliminary study, our aim was to assess the utility of quantitative native-T₁ (T₁-pre), iron-corrected T₁ (cT₁) of the liver/spleen and T₁ mapping of the liver obtained during hepatobiliary phase (T₁-HBP) post-gadoxetate disodium, compared to spleen size/volume and APRI (aspartate aminotransferase-to-platelet ratio index) for noninvasive diagnosis of clinically significant portal hypertension [CSPH, defined as hepatic venous pressure gradient (HVPG) ≥ 10 mm Hg].

METHODS

Forty-nine patients (M/F: 27/22, mean age 53y) with chronic liver disease, HVPG measurement and MRI were included. Breath-held T₁ and cT₁ measurements were obtained using an inversion recovery Look-Locker sequence and a T2* corrected modified Look-Locker sequence, respectively. Liver T₁-pre (n = 49), spleen T₁ (obtained pre-contrast, n = 47), liver and spleen cT₁ (both obtained pre-contrast, n = 30), liver T₁-HBP (obtained 20 min post gadoxetate disodium injection, n = 36) and liver T₁ uptake (ΔT₁, n = 36) were measured. Spleen size/volume and APRI were also obtained. Spearman correlation coefficients were used to assess the correlation between each of liver/spleen T₁/cT₁ parameters, spleen size/volume and APRI with HVPG. ROC analysis was performed to determine the performance of measured parameters for diagnosis of CSPH.

RESULTS

There were 12/49 (24%) patients with CSPH. Liver T₁-pre (r = 0.287, p = 0.045), liver T₁-HBP (r = 0.543, p = 0.001), liver ΔT₁ (r =  - 0.437, p = 0.008), spleen T₁ (r = 0.311, p = 0.033) and APRI (r = 0.394, p = 0.005) were all significantly correlated with HVPG, while liver cT₁, spleen cT₁ and spleen size/volume were not. The highest AUCs for the diagnosis of CSPH were achieved with liver T₁-HBP, liver ΔT₁ and spleen T₁: 0.881 (95%CI 0.76-1.0, p = 0.001), 0.852 (0.72-0.98, p = 0.002) and 0.781 (0.60-0.95, p = 0.004), respectively.

CONCLUSION

Our preliminary results demonstrate the potential of liver T₁ mapping obtained during HBP post gadoxetate disodium for the diagnosis of CSPH. These results require further validation.

Radiation segmentectomy for curative intent of unresectable very early to early stage hepatocellular carcinoma (RASER): a single-centre, single-arm study

BACKGROUND

Unresectable solitary very early to early stage hepatocellular carcinoma is managed with ablation for curative intent. Radiation segmentectomy is a treatment option that delivers radioactive ⁹⁰yttrium (⁹⁰Y)-bound microspheres transarterially to a segment of liver. The aim of this study was to assess the safety and efficacy of radiation segmentectomy in patients with unresectable hepatocellular carcinoma deemed unfavourable for ablation.

METHODS

RASER was a single-centre, single-arm study that included adults (>18 years) with solitary hepatocellular carcinoma with unfavourable location for ablation, without metastasis or macrovascular invasion. Eligibility criteria included measurable disease 3 cm or less in diameter, Child-Pugh score A-B7, an Eastern Cooperative Oncology Group score of 0, and adequate haematological and organ function. The primary endpoint was target tumour response measured by mRECIST. Patients were followed up with imaging and office visits for up to 24 months. The trial is registered with ClinicalTrials.gov (NCT03248375), and is completed.

FINDINGS

Individuals were enrolled between Aug 3, 2016, and April 4, 2019, and the last patient follow-up occurred on March 31, 2021. Of the 44 individuals assessed for eligibility, 29 patients were included in the study. Initial target lesion complete response was observed in 24 (83%) of 29 patients, and partial response was observed in five (17%) of patients. All patients had an initial objective response and 26 (90%) individuals had a sustained complete response. Four (14%) patients had grade 3 leukopenia and two (7%) had grade 3 thrombocytopenia. There were two (7%) non-laboratory-related grade 3 adverse events (one arterial injury and one ascites). The most frequent (>10% patients) grade 1 or 2 adverse events were fatigue (nine [31%]); nausea, vomiting, or anorexia (seven [24%]); abdominal discomfort (six [21%]), leukopenia (nine [31%]), thrombocytopenia (four [14%]), increased alkaline phosphatase (four [14%]), increased alanine or aspartate aminotransferase (four [14%]), increased bilirubin (four [14%]), and decreased albumin (six [21%]). There was one death that was not treatment related.

INTERPRETATION

Radiation segmentectomy was efficacious, with a low proportion of high-grade adverse events in patients with unresectable very early to early stage hepatocellular carcinoma with suboptimal location for ablation. These results suggest that radiation segmentectomy should be further investigated as a potential curative treatment option for well selected patients.

FUNDING

Boston Scientific.

MR elastography outperforms shear wave elastography for the diagnosis of clinically significant portal hypertension

OBJECTIVES

Portal hypertension (PH) is associated with complications such as ascites and esophageal varices and is typically diagnosed through invasive hepatic venous pressure gradient (HVPG) measurement, which is not widely available. In this study, we aim to assess the diagnostic performance of 2D/3D MR elastography (MRE) and shear wave elastography (SWE) measures of liver and spleen stiffness (LS and SS) and spleen volume, to noninvasively diagnose clinically significant portal hypertension (CSPH) using HVPG measurement as the reference.

METHODS

In this prospective study, patients with liver disease underwent 2D/3D MRE and SWE of the liver and spleen, as well as HVPG measurement. The correlation between MRE/SWE measures of LS/SS and spleen volume with HVPG was assessed. ROC analysis was used to determine the utility of MRE, SWE, and spleen volume for diagnosing CSPH.

RESULTS

Thirty-six patients (M/F 22/14, mean age 55 ± 14 years) were included. Of the evaluated parameters, 3D MRE SS had the strongest correlation with HVPG (r = 0.686, p < 0.001), followed by 2D MRE SS (r = 0.476, p = 0.004). 3D MRE SS displayed the best performance for diagnosis of CSPH (AUC = 0.911) followed by 2D MRE SS (AUC = 0.845) and 3D MRE LS (AUC = 0.804). SWE SS showed poor performance for diagnosis of CSPH (AUC = 0.583) while spleen volume was a fair predictor (AUC = 0.738). 3D MRE SS was significantly superior to SWE LS/SS (p ≤ 0.021) for the diagnosis of CSPH.

CONCLUSION

SS measured with 3D MRE outperforms SWE for the diagnosis of CSPH. SS appears to be a useful biomarker for assessing PH severity. These results need further validation.

KEY POINTS

• Spleen stiffness measured with 2D and 3D MR elastography correlates significantly with hepatic venous pressure gradient measurement. • Spleen stiffness measured with 3D MR elastography demonstrates excellent performance for the diagnosis of clinically significant portal hypertension (AUC 0.911). • Spleen stiffness measured with 3D MR elastography outperforms liver and spleen stiffness measured with shear wave elastography for diagnosis of clinically significant portal hypertension.

Assessment of HCC response to Yttrium-90 radioembolization with gadoxetate disodium MRI: correlation with histopathology

BACKGROUND AND AIMS

Transarterial ⁹⁰Y radioembolization (TARE) is increasingly being used for hepatocellular carcinoma (HCC) treatment. However, tumor response assessment after TARE may be challenging. We aimed to assess the diagnostic performance of gadoxetate disodium MRI for predicting complete pathologic necrosis (CPN) of HCC treated with TARE, using histopathology as the reference standard.

METHODS

This retrospective study included 48 patients (M/F: 36/12, mean age: 62 years) with HCC treated by TARE followed by surgery with gadoxetate disodium MRI within 90 days of surgery. Two radiologists evaluated tumor response using RECIST1.1, mRECIST, EASL, and LI-RADS-TR criteria and evaluated the percentage of necrosis on subtraction during late arterial, portal venous, and hepatobiliary phases (AP/PVP/HBP). Statistical analysis included inter-reader agreement, correlation between radiologic and pathologic percentage of necrosis, and prediction of CPN using logistic regression and ROC analyses.

RESULTS

Histopathology demonstrated 71 HCCs (2.8 ± 1.7 cm, range: 0.5-7.5 cm) including 42 with CPN, 22 with partial necrosis, and 7 without necrosis. EASL and percentage of tumor necrosis on subtraction at the AP/PVP were independent predictors of CPN (p = 0.02-0.03). Percentage of necrosis, mRECIST, EASL, and LI-RADS-TR had fair to good performance for diagnosing CPN (AUCs: 0.78 - 0.83), with a significant difference between subtraction and LI-RADS-TR for reader 2, and in specificity between subtraction and other criteria for both readers (p-range: 0.01-0.04). Radiologic percentage of necrosis was significantly correlated to histopathologic degree of tumor necrosis (r = 0.66 - 0.8, p < 0.001).

CONCLUSIONS

Percentage of tumor necrosis on subtraction and EASL criteria were significant independent predictors of CPN in HCC treated with TARE. Image subtraction should be considered for assessing HCC response to TARE when using MRI.

KEY POINTS

• Percentage of tumor necrosis on image subtraction and EASL criteria are significant independent predictors of complete pathologic necrosis in hepatocellular carcinoma treated with⁹⁰Y radioembolization. • Subtraction, mRECIST, EASL, and LI-RADS-TR have fair to good performance for diagnosing complete pathologic necrosis in hepatocellular carcinoma treated with⁹⁰Y radioembolization.

Omphalitis with Umbilical Abscess in an Adult with a Urachal Remnant

Omphalitis is an inflammation of the umbilicus and is seldom diagnosed in adults. It is even rarer when it results from an infection of the urachus, an embryological remnant that connects the umbilicus to the dome of the bladder. Patients with omphalitis present with erythema, edema, tenderness, and purulent discharge form the umbilical stump. Workup includes ultrasonography and CT scan of the abdomen and pelvis. Management consists of antibiotics and incision and drainage of the umbilical abscess, followed by surgical resection of the urachal remnant. In this article, we report a case of omphalitis complicated by umbilical abscess in a 20-year-old female with a urachal remnant.

Intertrochanteric fractures treated by diaphyseal support arthroplasty with hook plate vs cerclage wires only: A retrospective cohort study

Background

The treatment of unstable fractures of the intertrochanteric region of the hip in the elderly is controversial. Conventionally, internal fixation with intramedullary nail or a dynamic hip screw is the treatment of choice in intertrochanteric fractures. Nowadays, some authors encouraged the use hip arthroplasty for management of these fractures with good outcome. The aim of this study is to compare total hip arthroplasty with hook plate against total hip arthroplasty with cerclage cables in the management of unstable intertrochanteric fractures.

Materials and methods

Out of 100 admitted patients to a central university hospital in Beirut between 2013 and 2019 with a diagnosis of unstable intertrochanteric fracture of the hip, only 64 (36 hook plate vs 28 cerclage) patients were selected. This is a retrospective study, patients were excluded if lost to follow up, or if follow up less than one year is available. The data were retrieved from inpatient and outpatient hospital files. Functional outcomes were assessed according to ambulatory capacity. The main clinical measures were early postoperative full weight bearing, postoperative complications, functional outcome and radiologic assessment done by a radiologist in addition to measuring the dysfunction via the Harris Hip Score.

Results

The time to full weight bearing, the rate of postoperative complications, radiologic outcome and the functional outcomes were more satisfactory in the hook - plate group than in the cerclage - cable group.

Conclusion

According to the results, total hip arthroplasty with hook plate is considered the preferred modality of treatment in mobile elderly patients above sixty-five years of age with an unstable intertrochanteric femoral fracture, despite being a bulky foreign material that can lead to trochanteric bursitis.

Modified Mitchell technique for treating hallux valgus: Retrospective case series on a Middle-Eastern population and literature review

Introduction

The hallux valgus deformity is a complex deformity of the first ray of the foot, with more than 100 procedures developed for its treatment. The aim of this retrospective study was to assess the clinical and radiographic outcomes of a modified Mitchell's technique.

Methods

Between 2007 and 2018, 75 patients underwent the procedure. Clinical results were assessed by the AOFAS score. Radiological studies were evaluated by measuring pre-operative and post-operative HVA and IMA angles as well as the relative shortening of the first metatarsal.

Results

Of the initial 75 patients, 42 patients remained eligible with a total of 67 feet. The mean age and follow-up were 47.8 and 5.2 years respectively. Global AOFAS score improved from 45.3 to 88.8 (p < 0.01). Mean HVA and IMA improved from 37.0 to 10.2 (p < 0,01) and 12.1 to 5.6 (p < 0.01), respectively. The mean metatarsal shortening was 3.0 mm (p < 0.01). The statistical analysis showed no significant correlation between preoperative HVA and IMA angles with postoperative shortening, metatarsalgia, AOFAS scores nor the difference between the preoperative and postoperative AOFAS scores.

Conclusion

Short- and long-term outcomes of this modified Mitchell's osteotomy have been reported. Compared to other studies, these modifications proved to result in very good clinical and radiological outcomes even in severe cases with HVA>40. It has shown to be reliable, reproducible, and cost-efficient with low complication rates. We would like to highlight the importance of proper patient selection, limited soft tissue stripping, and adherence to the proposed surgical steps to avoid unwanted complications.

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The Modified Mitchell Technique has been shown to be reliable, reproducible, and cost-efficient with low complication rates.

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The addition of intra-articular lateral soft tissue release, preventing a lateral incision, decreasing wound and soft tissue complications.

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The use of autologous bone graft adjacent to the osteotomy stump helps improve union.

Clinicopathology and Diagnosis Delay in a 40-Year-Old with Mitochondrial Neurogastrointestinal Encephalomyopathy (MNGIE)

Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is an autosomal recessive and fatal multisystem metabolic disorder. It presents with wide-ranging gastrointestinal and neurologic symptoms. It is caused by a mutation in the TYMP gene which impairs thymidine phosphorylase (TP) activity, therefore leading to the accumulation of thymidine and deoxyuridine in plasma and tissues. Thus, MNGIE can be diagnosed by findings of high levels of thymidine and deoxyuridine. Herein, we present the case of a 40-year-old male who presented with diarrhea, vomiting, and abdominal pain, severe weight loss, neurologic deficits, and distal motor weakness progressing over a period of 13 years. The combination of this broad clinical picture along with results of magnetic resonance imaging, electromyography, colonic biopsies, genetic testing, and elevated plasma and tissue thymidine and deoxyuridine levels confirmed the diagnosis of MNGIE. TYMP gene mutation impairs TP function. TP mutations in the nuclear DNA lead to mitochondrial DNA deletions causing mitochondrial failure and ultimately cell death. Treatment modalities are targeting the restoration of TP activity or aiming to decrease the high levels of thymidine and pyrimide. However, diagnosing this disease is still a challenge and often overdue. This patient's 13-year delay in diagnosis shows the importance of a complete neurological exam and muscle strength testing in patients with gastrointestinal symptoms. The diagnosis of MNGIE requires interdepartmental collaborative work for diagnosis delay prevention and for optimal patient care.

Association of acromial morphological parameters and rotator cuff tears, and evaluation of the influence of age and gender on the parameters and impact on cuff tears: A study on a Middle Eastern population

Objective

The aim of this study is to evaluate the presence of significant differences regarding the lateral acromial angle, critical shoulder angle, and the acromial index between patients with and without rotator cuff tears.

Method

The MRIs (Magnetic Resonnance Imaging) of 82 patients were studied. The rotator cuff tear group (RCT group) included 41 patients while the control group also included 41 patients without rotator cuff tears. Acromial parameters and demographical data were extracted for statistical analysis.

Results

No statistical significant difference was found in terms of the studied acromial parameters between patients with and without rotator cuff tears. No correlation was found between age and any of the studied parameters. LAA (Lateral Acromial Angle) was found to be significantly different between males and females of the studied sample. However, no difference was found between patients with and without rotator cuff tears when both genders were studied separately. Moreover, no statistical significant difference was found in terms of the studied acromial parameters between males and females when the RCT group and the control group were studied separately. When gender was the covariate in the one-way MANCOVA test, gender was not significantly dependent on the type of groups (RCT group vs control group).

Conclusion

The results obtained from this study suggested that the studied acromial parameters in patients with rotator cuff tears were not different from the parameters found in patients without rotator cuff tears. Moreover, gender was not found to influence the acromial parameters, with no subsequent effect on the development of rotator cuff tears. Further studies may be required for better understanding on the biomechanics, taking into consideration age, gender, and the given population.

Is there an association between glenoid parameters and rotator cuff tears and the influence of gender: A retrospective study on a Middle Eastern population

OBJECTIVE

This study aims to investigate the presence of any differences between the normal population and patients with rotator cuff tears in term of glenoid morphological parameters.

METHOD

For the purpose of this study, 82 shoulder MRIs were evaluated. The individuals included in this study were divided into the patient group (cuff tear group, n = 41) and the control group (control group, n = 41) with respect to the inclusion and exclusion criteria. For the statistical analysis, SPSS software was used.

RESULTS

Statistically significant difference was found between the patient group and the control group in terms of Glenoid Version Angle (GVA), Glenoid Axial Width (GAW), Glenoid Axial Depth (GAD), Glenoid Coronal Depth (GCD), and the Glenoid Inclination Angle (GIA). Age was found to have a positive linear correlation with the glenoid coronal height. Moreover, statistically significant difference was found between the males and females, between males with cuff tears and control males, and females with cuff tears and control females in terms of glenoid parameters. When gender was a covariate, statistically significant differences in glenoid parameters was still present between cuff tears patients and individuals with control shoulders.

CONCLUSION

The results attained in this study are suggest that the GVA, GAW, GAD, GCD, and GIA in rotator cuff tear patients are different than those found in control patients. These measurements may be helpful in reaching the diagnosis in cases where the clinical diagnosis is equivocal. Moreover, these measurements may be helpful in planning tears management. The influence of gender on glenoid parameters and subsequent impact on shoulder pathology may help to better understand the biomechanism of rotator cuff tears and reach an individualized management for better patient care.

Detecting exercise-induced ischemia in left bundle branch block using the electrocardiogram

We compared 12-lead electrocardiographic changes during exercise in 41 patients with left bundle branch block; 7 were nonischemic and 34 had coronary artery obstruction > or =70% as detected by angiogram. ST depression of > or =0.5 mm from baseline when measured at the J point in leads II and AVF (p=0.004) and an increase of R-wave amplitude in lead II (p=0.05) significantly identified ischemia.

EGFR signaling is required for the differentiation and maintenance of neural progenitors along the dorsal midline of the Drosophila embryonic head

EGFR signaling has been shown in recent years to be involved in the determination, differentiation and maintenance of neural and epidermal cells of the ventral midline (mesectoderm and ventromedial ectoderm). Localized activation of the TGFalpha homolog Spitz (Spi) in the mesectoderm is achieved by the products of the genes rhomboid and Star. Spi binds to its receptor, the Drosophila epidermal growth factor receptor homolog (Egfr), and triggers the Ras pathway which is needed for the survival and differentiation of ventral midline cells. The results reported here indicate that EGFR signaling is also required in a narrow medial domain of the head ectoderm (called ‘head midline’ in the following) that includes the anlagen of the medial brain, the visual system (optic lobe, larval eye) and the stomatogastric nervous system (SNS). We document that genes involved in EGFR signaling are expressed in the head midline. Loss of EGFR signaling results in an almost total absence of optic lobe and larval eye, as well as severe reduction of SNS and medial brain. The cellular mechanism by which this phenotype arises is a failure of neurectodermal cells to differentiate combined with apoptotic cell death. Overactivity of EGFR signaling, as achieved by heat-shock-driven activation of a wild-type rhomboid (rho) construct, or by loss of function of argos (aos) or yan, results in an hyperplasia and deformity of the head midline structures. We show that, beside their requirement for EGFR signaling, head and ventral midline structures share several morphogenetic and molecular properties.

Treatment of premalignancy: prevention of lymphoma in radiation leukemia virus-inoculated mice by cyclosporin A and immunotoxin

Radiation leukemia virus (RadLV)-induced preleukemic (PL) latency is characterized by the appearance of virus-infected PL cells in the thymus. The survival of these PL cells is dependent upon autostimulation with interleukin 4 (IL-4). We have intervened prophylactically in RadLV-induced preleukemia by using cyclosporin-A (CSA), which inhibits IL-4 production, and an immunotoxin (ITx) that kills PL cells. CSA efficiently inhibited IL-4 secretion from RadLV-induced PL and leukemic cells, and its administration to PL mice caused a significant delay in their death. An ITx consisting of anti-RadLV glycoprotein-70 (gp70) antibody coupled to ricin A chain efficiently inhibited protein synthesis in virus-infected cells in vitro and, when injected into PL mice, also delayed their death. Combined treatment with CSA and ITx prevented 75% of the treated PL mice from developing lymphoma. These results show that the development of malignancy from a premalignant state can be averted by a combination of therapeutic modalities that decrease the size and growth rate of the premalignant cell population.