Reossification of Bone Defects After Surgical Correction of Nonsyndromic Craniosynostosis: A Review and An Original Study.

BACKGROUND AND OBJECTIVES: Surgical correction of nonsyndromic craniosynostosis (NSC) aims to restore cranial shape. Reossification of bone defects is paramount for the best aesthetic prognosis. However, the literature on the quantitative evaluation of bone defects after NSC surgery is scarce. This study aimed to quantify and analyze the surface area of bone defects after NSC surgery and establish a threshold value for predicting persistent defects. METHODS: We conducted a systematic review and a prospective study of 28 children undergoing surgical treatment for NSC. We analyzed 426 defects on the first computed tomography scan (1 year postoperative) and 132 defects on the second computed tomography scan (4.6 years postoperative). Statistical analysis was performed using Spearman's rank correlation coefficient, Mann-Whitney-Wilcoxon rank-sum test, and Youden's J statistic. RESULTS: Our systematic review identified three studies reporting on bone defects' surface area and reossification rate. In our study, we found no statistically significant differences in the number or size of defects between sex or type of NSC. The threshold value for the surface area of bone defects above which there was a higher probability of persistent defects was 0.19 cm2 (Youden point), with an 89.47 % probability of persistence. Defects with a surface area below 0.19 cm2 had a considerably lower probability, only 15.07%, of persistence over time. CONCLUSION: Our study provides valuable quantitative data for managing bone defects after NSC surgery. Defects with a surface area above 0.19 cm2 should be monitored with radiological imaging because of the risk of persistence. Our findings highlight the importance of developing robust and reproducible methods for the quantitative analysis of bone defects after NSC surgery.

Metastatic melanoma treated by immunotherapy: discovering prognostic markers from radiomics analysis of pretreatment CT with feature selection and classification.

PURPOSE: Immunotherapy has dramatically improved the prognosis of patients with metastatic melanoma (MM). Yet, there is a lack of biomarkers to predict whether a patient will benefit from immunotherapy. Our aim was to create radiomics models on pretreatment computed tomography (CT) to predict overall survival (OS) and treatment response in patients with MM treated with anti-PD-1 immunotherapy. METHODS: We performed a monocentric retrospective analysis of 503 metastatic lesions in 71 patients with 46 radiomics features extracted following lesion segmentation. Predictive accuracies for OS < 1 year versus > 1 year and treatment response versus no response was compared for five feature selection methods (sequential forward selection, recursive, Boruta, relief, random forest) and four classifiers (support vector machine (SVM), random forest, K-nearest neighbor, logistic regression (LR)) used with or without SMOTE data augmentation. A fivefold cross-validation was performed at the patient level, with a tumour-based classification. RESULTS: The highest accuracy level for OS predictions was obtained with 3D lesions (0.91) without clinical data integration when combining Boruta feature selection and the LR classifier, The highest accuracy for treatment response prediction was obtained with 3D lesions (0.88) without clinical data integration when combining Boruta feature selection, the LR classifier and SMOTE data augmentation. The accuracy was significantly higher concerning OS prediction with 3D segmentation (0.91 vs 0.86) while clinical data integration led to improved accuracy notably in 2D lesions (0.76 vs 0.87) regarding treatment response prediction. Skewness was the only feature found to be an independent predictor of OS (HR (CI 95%) 1.34, p-value 0.001). CONCLUSION: This is the first study to investigate CT texture parameter selection and classification methods for predicting MM prognosis with treatment by immunotherapy. Combining pretreatment CT radiomics features from a single tumor with data selection and classifiers may accurately predict OS and treatment response in MM treated with anti-PD-1.

Mechanical complications of cerebrospinal fluid shunt. Differences between adult and pediatric populations: myths or reality?

OBJECTIVE: Shunt malfunctions seem more frequent in children (44 to 81%) than in adults (18 to 29%). Because of discrepancies between studies, it is not possible to affirm this disparity. The objective was to verify whether the incidence of cerebrospinal fluid (CSF) shunt malfunctions is higher in children than adults. METHODS: We present a retrospective series of child and adult patients who underwent CSF shunt placement between 2000 and 2013 with a Sophysa SM8® valve. RESULTS: 599 adults and 98 children (sex ratio 1.28) underwent CSF shunt placement. Age at first surgery ranged between 1 day of life and 90 years (mean of 55.8 years, SD 25.8, median 64.8 years). The mean follow-up was 4 years (SD 4.264, 0-16; median 3 years). The cumulative complication rate was 25.5% (178/697). Mechanical complications were disconnection (25.1%), migration (11.8%), intracranial catheter obstruction (8.9%) and malposition (8.4%). The mean delay for the first revision was 1.90 years (0-13.9), (SD 2.73, median 0.5). The probability of shunt failure was 65% at 10 years in the child group and 36% at 10 years in the adult group. Moreover, in the child group, 33% of revisions occurred during the first year after shunt placement versus 17% in the adult group. Thus, the probability of shunt failure was higher in children than in adults (log-rank test, p < 0.001). CONCLUSIONS: This is the first retrospective study, comparing children and adults undergoing CSF shunt using the same valve, able to confirm the higher rate of complications in children.

Quantification of steatosis in alcoholic and nonalcoholic fatty liver disease: Evaluation of four MR techniques versus biopsy.

PURPOSE: Given the growing prevalence of obesity and metabolic syndrome, the management of hepatic steatosis, especially its quantification, is a major issue. We assessed the quantification of liver steatosis using four different MR methods, in order to determine the one that is best correlated with the reference method which consists of histological measurement by liver biopsy. METHOD: Seventy-one successive patients requiring liver biopsy for acute or chronic liver disease were enrolled prospectively between March 2017 and March 2018, 11 were excluded and 60 were reported. Liver MR (1.5 T) was organised in order to be performed the same day, using four different steatosis quantification techniques (3-echo MRI, 6-echo MRI, 11-echo MRI and MR Spectroscopy). Quantitative histological and imaging data were compared. In a secondary analysis, we studied the possible influence of alcohol drinking, hepatic iron overload, and the presence of liver fibrosis. RESULTS: All four MR techniques were found to have excellent correlations with the histological measurements: 3-echo MRI (r = 0.852, p < 0.001), 6-echo MRI (r = 0.819, p < 0.001), 11-echo MRI (r = 0.818, p < 0.001) and MR Spectroscopy (r = 0,812, p < 0,001). Interestingly, we also found that the presence of alcohol consumption, iron overload and fibrosis did not interfere with measurements, whichever technique was used. CONCLUSION: In the evaluation of hepatic steatosis, our study showed very good correlations of all four MR techniques with the histological standard. There was no confounding factor in a representative group of patients with associated liver conditions such as alcohol consumption, fibrosis and iron overload, for each technique. All four MR techniques may be used in daily practice.

Individual radiation exposure from computed tomography: a survey of paediatric practice in French university hospitals, 2010-2013.

OBJECTIVES: To describe computed tomography (CT) scanning parameters, volume CT dose index (CTDIvol) and dose-length product (DLP) in paediatric practice and compare them to current diagnostic reference levels (DRLs). METHODS: The survey was conducted in radiology departments of six major university hospitals in France in 2010-2013. Data collection was automatised to extract and standardise information on scanning parameters from DICOM-header files. CTDIvol and DLP were estimated based on Monte Carlo transport simulation and computational reference phantoms. RESULTS: CTDIvol and DLP were derived for 4,300 studies, four age groups and 18 protocols. CTDIvol was lower in younger patients for non-head scans, but did not vary with age for routine head scans. Ratios of 95th to 5th percentile CTDIvol values were 2-4 for most body parts, but 5-7 for abdominal examinations and 4-14 for mediastinum CT with contrast, depending on age. The 75th percentile CTDIvol values were below the national DRLs for chest (all ages) and head and abdominal scans (≥10 years). CONCLUSION: The results suggest the need for a better optimisation of scanning parameters for routine head scans and infrequent protocols with patient age, enhanced standardisation of practices across departments and revision of current DRLs for children. KEY POINTS: • CTDIvol varied little with age for routine head scans. • CTDIvol was lowest in youngest children for chest or abdominal scans. • Individual and inter-department variability warrant enhanced standardisation of practices. • Recent surveys support the need for revised diagnostic reference levels. • More attention should be given to specific protocols (sinuses, neck, spine, mediastinum).

Hepatic capsular retraction: spectrum of diagnosis at MRI.

Hepatic capsular retraction is an imaging feature that deserves the attention of the radiologist. Hepatic capsular retraction is associated with a number of hepatic lesions, benign or malignant, treated or untreated. The purpose of this pictorial review is to discuss the most common benign and malignant hepatic lesions associated with this feature with an emphasis on magnetic resonance imaging (MRI).

Mixed endometrioid and serous carcinoma developing in abdominal wall endometriosis following Cesarean section.

Abdominal wall endometriosis is unusual and mostly occurs in scars following Cesarean section. Although malignant transformation is rare, it must be recognized in order to benefit from radical resection. We report a very rare case of mixed endometrioid and serous carcinoma developing in a Cesarean section endometriosis scar and the way we managed it using surgery and chemotherapy. 18-FDG PET-CT imaging was performed to correctly stage the disease.

Massive hepatic necrosis with gastric, splenic, and pancreatic infarctions after ethanol ablation for hepatocellular carcinoma.

Hepatic necrosis after ethanol ablation for hepatocellular carcinoma (HCC), although rare, is well known and described, particularly in patients with chronic liver disease. The present report describes a rare case of massive hepatic necrosis with partial gastric, splenic, and pancreatic infarctions after local treatment of liver HCC with ethanol ablation and discusses the reasons for this complication. With the increasing use of percutaneous techniques to treat liver tumors, it is imperative for the interventional radiologist to be aware of the potential vascular complications of these techniques. An appreciation of vascular anatomy via multidetector computed tomography (CT) and/or magnetic resonance (MR) angiography is important when planning image-guided interventions.

Cardiac tamponade after malignant superior vena cava stenting: Two case reports and brief review of the literature.

Percutaneous stenting of the superior vena cava (SVC) is usually recommended as a palliative procedure for malignant SVC obstruction with low reported morbidity. Complications are uncommon and usually of minor consequence. We report two unusual cases of cardiac tamponade following SVC stenting in patients with malignant SVC syndrome. Echocardiography allows rapid diagnosis and guides pericardial drainage in the interventional radiology suite.

Epithelioid hemangioendothelioma of the liver with metastatic coeliac lymph nodes in an 11-year-old boy.

Epithelioid hemangioendothelioma of the liver is a very rare vascular tumour in children with intermediate malignant potential. We present a case in which the typical imaging appearances of coalescent peripheral hepatic masses with capsular retraction contributed to the diagnosis. A positron emission tomography-CT (PET-CT) procedure was performed in staging the disease with a strong suspicion of coeliac nodal involvement confirmed after laparotomy and histological analysis. Our case is unique because of the rarity of the disease, the young age of the child, and proven nodal metastases at initial diagnosis. The use of PET-CT allows better staging at initial diagnosis and thus better management with improved follow-up in these patients.

[Vascular interventional procedures in oncology]. / Radiologie vasculaire interventionnelle en oncologie.

Indications for interventional radiology have increased, and various arterial and venous procedures are nowadays possible in oncology. Besides emergency procedures, scheduled palliative or curative procedures require multidisciplinary cooperation emphasizing on cautions related to iodine contrast media and concerning immunosuppresion, hemostasis disorders, analgesia, and the choice of the adequate approach. Diagnostic endovascular biopsies and venous sampling may be performed. Embolisation procedures are useful for achieving hemostasis, tumor devascularisation, or chemo-embolisation. Revascularisation procedures concern central vein obstructions, catheter occlusion or arterial stenoses and occlusions. Vena cava filtering, retrieval of intravascular foreign bodies and percutaneous implantation of ports can also be indicated, as well other treatments of central venous access complications. The principles, technical aspects, results, and indications of these various endovascular procedures are described in this review.

Endovascular treatment of chronic mesenteric ischemia: results in 14 patients.

We evaluated immediate and long-term results of percutaneous transluminal angioplasty (PTA) and stent placement to treat stenotic and occluded arteries in patients with chronic mesenteric ischemia. Fourteen patients were treated by 3 exclusive celiac artery (CA) PTAs (2 stentings), 3 cases with both Superior Mesenteric Artery (SMA) and CA angioplasties, and 8 exclusive SMA angioplasties (3 stentings). Eleven patients had atheromatous stenoses with one case of an early onset atheroma in an HIV patient with antiphospholipid syndrome. The other etiologies of mesenteric arterial lesions were Takayashu arteritis (2 cases) and a postradiation stenoses (1 case). Technical success was achieved in all cases. Two major complications were observed: one hematoma and one false aneurysm occurring at the brachial puncture site (14.3%). An immediate clinical success was obtained in all patients. During a follow-up of 1-83 months (mean: 29 months), 11 patients were symptom free; 3 patients had recurrent pain; in one patient with inflammatory syndrome, pain relief was obtained with medical treatment; in 2 patients abdominal pain was due to restenosis 36 and 6 months after PTA, respectively. Restenosis was treated by PTA (postirradiation stenosis), and by surgical bypass (atheromatous stenosis). Percutaneous endovascular techniques are safe and accurate. They are an alternative to surgery in patients with chronic mesenteric ischemia due to short and proximal occlusive lesions of SMA and CA.

Percutaneous transluminal angioplasty of dysplastic stenoses of the renal artery: results on 70 adults.

PURPOSE: Retrospective analysis of the dilatation (PTRA) of renal arterial dysplastic stenosis (RADS). METHODS: Seventy patients suffering from hypertension (87 RADS) were treated at our institution for medial (83%) or non-classified fibrodysplasias (17%). Four patients suffered from renal insufficiency. Two endoprostheses were implanted. We evaluated blood pressure with the USCSRH criteria and renal insufficiency with the Martin criteria. RESULTS: Ninety-five percent technical success and 87.9% clinical success for blood pressure were obtained, with worse results for patients older than 57 years or with a history of hypertension greater than 9 years. Results were better when the RADS was responsible for an ipsilateral renal atrophy or for poorly controlled hypertension. No renal insufficiency worsened during the follow-up. CONCLUSION: PTRA is a first-line treatment for renovascular hypertension caused by RADS. The results were encouraging despite a high average age of the subjects and frequent associated extrarenal vascular lesions.