Multi-parametric arterial spin labeling and diffusion-weighted imaging of paranasal sinuses masses.

PURPOSE: To evaluate arterial spin labeling (ASL) and diffusion-weighted imaging (DWI) in discrimination of benign from malignant paranasal sinus (PNS) tumors. MATERIAL AND METHODS: A prospective study was done upon 42 cases of PNS masses that underwent magnetic resonance ASL and DWI of the head. Tumor blood flow (TBF) and apparent diffusion coefficient (ADC) of the masses were calculated by two observers. The pathological diagnosis was malignant (n = 28) and benign (n = 14) cases. RESULTS: For both observers, the malignant PNS masses had significantly higher TBF (P < 0.001, 0.001) and lower ADC (P < 0.001, 0.001) than in benign masses. The ROC curve analysis of TBF, The threshed TBF was (121.45, 122.68 mL/100 g/min) used for differentiation between benign and malignant PNS masses, revealed sensitivity (92.9%, 89.3%), specificity (85.7%, 85.7%), accuracy (90.5%, 88.1%) and the AUC was 0.87 and 0.86 by both observers. the ROC curve analysis of ADC, The threshold ADC (1.215, 1.205 X10-3mm2/s) was used for differentiation between benign and malignant PNS masses, revealed sensitivity (96.4%, 89.3%), specificity (78.6%, 78.6%), accuracy of (90.5%, 85.7%) and the AUC was 0.93 and 0.92 by both observers. Combined analysis of TBF and ADC used for differentiation between benign and malignant PNS masses had revealed sensitivity (96.4%, 89.3%), specificity (92.9%, 85.7%) accuracy of (95.2%, 88.1%) and AUC. (0.995, 0.985) for both observers. CONCLUSION: Combined using of TBF and ADC have a role in differentiation malignant from benign PNS masses.

The value of the apparent diffusion coefficient value in the Liver Imaging Reporting and Data System (LI-RADS) version 2018.

PURPOSE: To assess role of the apparent diffusion coefficient (ADC) in the Liver Imaging Reporting and Data System (LI-RADS) version 2018 for the prediction of hepatocellular carcinoma (HCC). MATERIAL AND METHODS: Retrospective analysis of 137 hepatic focal lesions in 108 patients at risk of HCC, who underwent magnetic resonance imaging of the liver. Hepatic focal lesions were classified according to LI-RADS-v2018, and ADC of hepatic lesions was calculated by 2 independent blinded reviewers. RESULTS: The mean ADC of LR-1 and LR-2 were 2.11 ± 0.47 and 2.08 ± 0.47 × 10-3 mm2/s, LR-3 were 1.28 ± 0.12 and 1.36 ± 0.16 × 10-3 mm2/s, LR-4, LR-5 and LR-TIV were 1.07 ± 0.08 and 1.08 ± 0.12 × 10-3 mm2/s and LR-M were 1.02 ± 0.09 and 1.00 ± 0.09 × 10-3 mm2/s by both observers, respectively. There was excellent agreement of both readings for LR-1 and LR-2 (r = 0.988), LR-3 (r = 0.965), LR-4, LR-5 and LR-TIV (r = 0.889) and LR-M (r = 0.883). There was excellent correlation between ADC and LI-RADS-v2018 (r = -0.849 and -0.846). The cut-off ADC used to differentiate LR-3 from LR-4, LR-5, and LR-TIV were ≤ 1.21 and ≤ 1.23 × 10-3 mm2/s with AUC of 0.948 and 0.926. CONCLUSIONS: Inclusion of ADC to LI-RADS-v2018 improves differentiation variable LI-RADS categories and can helps in the prediction of HCC.

The relevance of left ventricular functions to clinical and metabolic characteristics of prepubertal children with obesity.

BACKGROUND: Paediatric obesity is a worldwide health burden, with growing evidence linking obesity to myocardial function impairments. The study aims to evaluate left ventricular functions among prepubertal obese children to obesity-related clinical and metabolic parameters. METHODS: Between June 2019 and March 2020, 40 prepubertal children with obesity were recruited and compared to 40 healthy controls. Patients were assessed for body mass index z scores, waist circumference, body adiposity by bioimpedance analysis, and obesity-related laboratory tests, for example, serum chemerin. Left ventricular functions were assessed using variable echocardiographic modalities, such as M-mode, tissue Doppler, and two-dimensional speckle tracking. RESULTS: Mean patients' age was 9.25 ± 1.05 years. Left ventricular mass index, E/E', and myocardial performance index were significantly increased in obese children than controls. Although M-mode-derived ejection fraction was comparable in both groups, two-dimensional speckle tracking-derived ejection fraction, global longitudinal strain, and global circumferential strain were significantly lower in cases than controls. Left ventricular mass index displayed a positive correlation with body mass index z score (p = 0.003), fat mass index (p = 0.037), and trunk fat mass (p = 0.021). Global longitudinal strain was negatively correlated with body mass index z score (p = 0.015) and fat mass index (p = 0.016). Serum chemerin was positively correlated with myocardial performance index (p = 0.01). CONCLUSION: Alterations of left ventricular myocardial functions in prepubertal obese children could be detected using different echocardiographic modalities. Chemerin, body mass index z score, fat mass index, and trunk fat mass were correlated with subclinical left ventricular myocardial dysfunction parameters before puberty. Our results reinforce early and strict management of childhood obesity upon detection of changes in anthropometric and body adiposity indices.

Effect of changes in optic nerve elasticity on central retinal artery blood flow in patients with idiopathic intracranial hypertension.

PURPOSE: To assess changes in central retinal artery (CRA) blood flow by orbital color-coded Doppler ultrasonography in patients with idiopathic intracranial hypertension (IIH) and their relation with optic nerve (ON) elasticity assessed by shear wave elastography (SWE). METHODS: This study was carried out on 68 eyes of patients diagnosed with IIH and 32 eyes of healthy controls. The severity of papilledema in IIH patients was sub-classified into mild and moderate/severe groups. Color-coded Doppler was used to measure peak systolic velocity (PSV), end diastolic velocity (EDV), mean velocity (Vmean) and pulsatility index (PI) of the CRA. RESULTS: PSV, Vmean, and SWE were significantly higher in patients with IIH than in controls (p = 0.001). The optimal cut-off values of PSV and Vmean for differentiating IIH patients from controls were 11.25 and 6.75 cm/s with AUC 0.81 and 0.785 respectively. AUC was 0.92 and accuracy 91% for combined PSV, Vmean and SWE differentiation between IIH patients and controls. PSV, Vmean and SWE were significantly different between mild versus moderate/severe papilledema (p = 0.001). PSV and Vmean were correlated with papilledema (r = 0.790 and 0.722 respectively) and SWE (r = 0.818 and 0.761 respectively). CONCLUSION: IIH is associated with decreased ON elasticity and reduced CRA blood flow. Individual and combined color-coded Doppler of the CRA and SWE help in diagnosis of IIH. CRA hemodynamic changes are correlated with papilledema severity and with the extent of biomechanical changes in the ON represented by SWE.

Combined accuracy of optic nerve sheath diameter, strain ratio, and shear wave elastography of the optic nerve in patients with idiopathic intracranial hypertension.

PURPOSE: This study assessed the combined accuracy of optic nerve sheath diameter (ONSD), strain ratio (SR), and shear wave elastography (SWE) of the optic nerve (ON) in patients with idiopathic intracranial hypertension (IIH). METHODS: This prospective study was carried out on both ONs of 34 consecutive patients diagnosed with IIH and 16 age- and sex-matched healthy volunteers. All of the study participants were women. The ONSD, SR, and SWE of the ON were measured. The severity of papilledema of IIH patients was sub-classified into mild papilledema and moderate/severe papilledema. RESULTS: The mean ONSD (5.6±1.1 mm), SR (0.7±0.1), and SWE (30.1±16.7 kPa) of the IIH patients were significantly different (P=0.001) from the ONSD (4.1±0.5 mm), SR (0.9±0.1), and SWE (8.2±3.4 kPa) of controls. The cutoff values of ONSD, SR, and SWE of the ON for differentiating IIH patients from controls were 5.45 mm, 0.8, and 10.3 kPa with areas under the curve (AUCs) of 0.91, 0.86, and 0.96 and accuracy values of 91%, 81%, and 93%, respectively. Combined SWE and ONSD and combined SWE, ONSD, and SR for differentiating IIH patients from controls revealed AUCs of 0.98 and 0.99 and accuracy values of 96% and 96%, respectively. ONSD, SR, and SWE showed significant differences between mild and moderate/severe papilledema (P=0.001). Papilledema was correlated with SWE (r=0.8, P=0.001), ONSD (r=0.4, P=0.001), and SR (r=-0.4, P=0.001). CONCLUSION: The combination of ONSD, SR, and SWE may be helpful for diagnosing IIH, and a good indicator of the degree of papilledema.

Diffusion Tensor Imaging of Auditory Pathway in Patients With Crigler-Najjar Syndrome Type I: Correlation With Auditory Brainstem Response.

AIM: To evaluate the role of diffusion tensor imaging of the auditory pathway in patients with Crigler Najjar syndrome type I and its relation to auditory brainstem response. METHODS: Prospective study was done including 12 patients with Crigler Najjar syndrome type I and 10 age- and sex-matched controls that underwent diffusion tensor imaging of brain. Mean diffusivity and fractional anisotropy at 4 regions of the brain and brainstem on each side were measured and correlated with the results of auditory brainstem response for patients. RESULTS: There was significantly higher mean diffusivity of cochlear nucleus, superior olivary nucleus, inferior colliculus, and auditory cortex of patients versus controls on both sides for all regions (P = .001). The fractional anisotropy of cochlear nucleus, superior olivary nucleus, inferior colliculus, and auditory cortex of patients versus controls was significantly lower, with P values of, respectively, .001, .001, .003, and .001 on the right side and .001, .001, .003, and .001 on left side, respectively. Also, a negative correlation was found between the maximum bilirubin level and fractional anisotropy of the left superior olivary nucleus and inferior colliculus of both sides. A positive correlation was found between the mean diffusivity and auditory brainstem response wave latency of the right inferior colliculus and left cochlear nucleus. The fractional anisotropy and auditory brainstem response wave latency of the right superior olivary nucleus, left cochlear nucleus, and inferior colliculus of both sides were negatively correlated. CONCLUSION: Diffusion tensor imaging can detect microstructural changes in the auditory pathway in Crigler Najjar syndrome type I that can be correlated with auditory brainstem response.

The role of diffusion tensor imaging of the liver in children with autoimmune hepatitis.

PURPOSE: To evaluate the role of diffusion tensor imaging (DTI) of the liver in children with autoimmune hepatitis (AIH). MATERIAL AND METHODS: A prospective study was done on 42 children with AIH (30 girls and 12 boys, with a mean age of 13 years) and 20 age- and sex-matched healthy control children. They underwent DTI of the liver and laboratory tests. Liver biopsy was done for the patients. The mean diffusivity (MD) and fractional anisotropy (FA) of the liver were calculated and correlated with the pathological results. RESULTS: The mean MD and FA of the liver in children with AIH were 1.42 ± 0.06 × 10-3 mm2/s and 0.37 ± 0.11; and in the control children they were 1.55 ± 0.07 × 10-3 mm2/s and 0.25 ± 0.03, respectively. The MD and FA were significantly different in the children with AIH compared to the control children (p = 0.001). The cutoff MD and FA used to differentiate patients from controls were 1.50 × 10-3 mm2/s, 0.31 with AUC of 0.919 and 0.813, sensitivity of 97.6% and 66.7%, a specificity of 80% and 70%, an accuracy of 94.2% and 67.3%, PPV of 95.3 and 90.3, and NPV of 88.9 and 33.3, respectively. There was significantly lower MD and higher FA of the liver in children with AIH type I (n = 31) than type II (n = 11) (p = 0.001), and patients with (n = 9) and without (n = 33) overlap syndrome (p = 0.005). CONCLUSIONS: We concluded that DTI parameters can help to diagnose AIH, detect its phenotyping, and give clues as to the presence of associated overlap syndrome.

Coronary artery disease imaging reporting and data system (CAD-RADS): what radiologists need to know?

The aim of this work is to review Coronary Artery Disease Imaging Reporting and Data System (CAD-RADS) that was designed to standardize reporting language and improve the communication of data among radiologists and clinicians. Stenotic lesions are graded into 5 grades ranging from 0 (no stenosis) to 5 (total occlusion), where the highest grade represents the final score. The expert consensus platform has added 4 special modifiers (non-diagnostic, stent, graft, and vulnerability) to aid patient management through linking these scores with decision algorithm and treatment plan. Adherence to standard imaging protocol; knowledge of normal, variant, and anomalous anatomy; and skillful evaluation of stenosis are important for proper utilization of this reporting system. Lastly, radiologists should be aware of the inherited benefits, limitations, and common pitfalls of this classification system.

Early assessment of lung function in coronavirus patients using invariant markers from chest X-rays images.

The primary goal of this manuscript is to develop a computer assisted diagnostic (CAD) system to assess pulmonary function and risk of mortality in patients with coronavirus disease 2019 (COVID-19). The CAD system processes chest X-ray data and provides accurate, objective imaging markers to assist in the determination of patients with a higher risk of death and thus are more likely to require mechanical ventilation and/or more intensive clinical care.To obtain an accurate stochastic model that has the ability to detect the severity of lung infection, we develop a second-order Markov-Gibbs random field (MGRF) invariant under rigid transformation (translation or rotation of the image) as well as scale (i.e., pixel size). The parameters of the MGRF model are learned automatically, given a training set of X-ray images with affected lung regions labeled. An X-ray input to the system undergoes pre-processing to correct for non-uniformity of illumination and to delimit the boundary of the lung, using either a fully-automated segmentation routine or manual delineation provided by the radiologist, prior to the diagnosis. The steps of the proposed methodology are: (i) estimate the Gibbs energy at several different radii to describe the inhomogeneity in lung infection; (ii) compute the cumulative distribution function (CDF) as a new representation to describe the local inhomogeneity in the infected region of lung; and (iii) input the CDFs to a new neural network-based fusion system to determine whether the severity of lung infection is low or high. This approach is tested on 200 clinical X-rays from 200 COVID-19 positive patients, 100 of whom died and 100 who recovered using multiple training/testing processes including leave-one-subject-out (LOSO), tenfold, fourfold, and twofold cross-validation tests. The Gibbs energy for lung pathology was estimated at three concentric rings of increasing radii. The accuracy and Dice similarity coefficient (DSC) of the system steadily improved as the radius increased. The overall CAD system combined the estimated Gibbs energy information from all radii and achieved a sensitivity, specificity, accuracy, and DSC of 100%, 97% ± 3%, 98% ± 2%, and 98% ± 2%, respectively, by twofold cross validation. Alternative classification algorithms, including support vector machine, random forest, naive Bayes classifier, K-nearest neighbors, and decision trees all produced inferior results compared to the proposed neural network used in this CAD system. The experiments demonstrate the feasibility of the proposed system as a novel tool to objectively assess disease severity and predict mortality in COVID-19 patients. The proposed tool can assist physicians to determine which patients might require more intensive clinical care, such a mechanical respiratory support.

Diffusion tensor imaging of renal cortex in lupus nephritis.

PURPOSE: To evaluate the diagnostic value of diffusion tensor imaging (DTI) of renal cortex in assessment of lupus nephritis (LN) and prediction of its pathological subtypes. METHODS: Prospective study was performed upon 39 female patients with pathologically proven LN and 16 sex- and age-matched healthy controls. Patients and controls underwent DTI of kidney. Mean diffusivity (MD) and fractional anisotropy (FA) of renal cortex were calculated by two radiologists. LN patients were pathologically classified into either non-proliferative (n = 15) or proliferative (n = 24). RESULTS: Mean MD of renal cortex in LN was significantly lower (p = 0.001) than that of controls with cut-off (2.16 and 2.2 X10-3mm2/s), area under curve (AUC) of (0.92, 0.94) and accuracy of (91%, 89%) for both observers. Mean FA of renal cortex in LN was significantly higher (p = 0.001) than that of controls with cut-off (0.20, 0.21), AUC of (0.86, 0.82) and accuracy of (86%, 84%) for both observers. Renal cortex MD and FA in non-proliferative LN were significantly different (p = 0.001) from that of proliferative LN for both observers. There was excellent inter-observer agreement of MD and FA (ICC = 0.96 and 0.81). CONCLUSION: MD and FA of renal cortex may help to assess renal affection in LN patients and predict its pathological subtypes.

Prostate Imaging Reporting and Data System (PI-RADS): What the radiologists need to know?

We aim to review the new modifications in MR imaging technique, image interpretation, lexicon, and scoring system of the last version of Prostate Imaging Reporting and Data System version 2.1 (PI-RADS v2.1) in a simple and practical way. This last version of PI-RADS v2.1 describes the new technical modifications in the protocol of Multiparametric MRI (MpMRI) including T2, diffusion-weighted imaging (DWI), and dynamic contrast enhancement (DCE) parameters. It includes also; new guidelines in the image interpretation specifications in new locations (lesions located in the central zone and anterior fibromuscular stroma), clarification of T2 scoring of lesions of the transition zone, the distinction between DWI score 2 and 3 lesions in the transition zone and peripheral zone, as well as between positive and negative enhancement in DCE. Biparametric MRI (BpMRI) along with simplified PI-RADS is gaining more acceptances in the assessment of clinically significant prostatic cancer.

Diffusion tensor imaging of vertebral bone marrow in children with Gaucher's disease type I and III: Pre- and post-therapy.

PURPOSE: To assess diffusion tensor imaging (DTI) of the vertebral bone marrow (BM) in children with Gaucher's disease (GD) types I and III before and after therapy. METHODS: Prospective study was conducted upon 25 children with GD type I (n = 17) and III (n = 8) and 13 age and sex-matched controls underwent DTI of vertebral BM. Mean diffusivity (MD) and fractional anisotropy (FA) of vertebral BM was calculated and correlated with genotyping, chitotriosidase, hemoglobin (HB) and, platelet count. RESULTS: There was a statistically significant difference in MD and FA of BM between patients and controls (P = 0.001 and 0.02). The area under the curve (AUC) of MD and FA used to differentiate untreated patients from controls was 0.902 and 0.68 with sensitivity, specificity, and, accuracy 92%, 84.6%, and, 89.5% respectively. There was a significant difference in MD and FA of BM between untreated and treated patients (P = 0.001 and 0.02). AUC of MD and FA used to differentiate untreated from treated patients was 0.93 and 0.649 with sensitivity, specificity, and accuracy of 92%, 80%, and 86% respectively. There was a significant difference in MD and FA (P = 0.03, 0.001 respectively) of BM in GD with homozygous L444P mutation (n = 9) and other mutations (n = 14). Chiotriptase, HB and platelet count of patients was correlated with MD (r = -0.36, 0.42, -0.41) and FA (r = -0.47, -0.37, -0.46) respectively. CONCLUSION: DTI of vertebral BM can help in diagnosis and monitoring patients with GD after therapy and correlated with genotyping, and hematological biomarkers of GD.

CT based Acute Appendicitis Severity Index for acute appendicitis and validate its effectiveness in predicting complicated appendicitis.

AIM: To propose a CT-based scoring system called Acute Appendicitis Severity Index (AASI) for diagnosis of acute appendicitis and validates its effectiveness in predicting complicated appendicitis. SUBJECTS AND METHODS: Retrospective analyses of CT images of 120 adult patients with pathologically proven uncomplicated (n = 64) and complicated (n = 56) acute appendicitis were performed. All patients had undergone a CT scan of the abdomen and pelvis using 320 multi-detectors computed tomography with Adaptive Iterative Dose Reduction 3D (AIDR 3D). CT image parameters were identified and used to develop a CT-based scoring system (AASI) to predict the severity of acute appendicitis and its outcome. All image analysis was performed by 2 radiologists and the total score was assigned to each patient based on the proposed CT scoring system. Validation of the effectiveness of the proposed scoring system (AASI) was done using statistical models. RESULTS: The mean and standard deviation of AASI was found to be significantly higher (P value = 0.001) in the complicated appendicitis group (observer 1 = 10.2 ± 1.6 and observer 2 = 9.63 ± 2.3) as compared to that in uncomplicated acute appendicitis group (observer 1 = 7.09 ± 2.2 and observer 2 = 6.38 ± 1.9). There was an excellent interobserver agreement of the Acute Appendicitis Severity Index for both the uncomplicated and complicated appendicitis groups (K = 0.89, 95% CI = 0.87-0.92, P = 0.001). The cutoff value for AASI used to predict complicated appendicitis was taken as 9.5 and 8.5. This resulted in an AUC of 0.877 and 0.848, accuracy of 83% and 81%, the sensitivity of 75% and 80%, the specificity of 90% and 81%, the positive predictive value of 87% and 78%, and a negative predictive value of 81% and 83% by both reviewers respectively. CONCLUSION: The proposed CT-based AASI is a reliable parameter for the prediction of complicated appendicitis.

Diffusion tensor imaging of the spleen in prediction and grading of esophageal varices in cirrhotic children with portal hypertension.

PURPOSE: To assess diffusion tensor imaging (DTI) of spleen in prediction and grading of esophageal varices (OV) in cirrhotic children. METHODS: This prospective study was conducted upon 30 children with cirrhotic children with OV and 10 age-gender matched controls that underwent DTI of abdomen. Mean diffusivity (MD) and fractional anisotropy (FA) of spleen were calculated and matched with the grading of OV at endoscopy and laboratory biomarkers of portal hypertension. RESULTS: Mean ADC of spleen in patient was significantly different (p = 0.001) from that of controls by both reviewers respectively. The cutoff ADC measurement of the spleen used for prediction of OV was ≥ 0.75 and ≥ 0.76 × 10-3mm2/s with AUC was 0.993 and 0.997 for both reviewers respectively. The FA of the spleen in patient was different (p = 0.01) from of controls of both reviewers respectively. Cutoff FA of spleen used for prediction of OV was ≤ 0.35 and ≤ 0.36 for both observers respectively. ADC and FA of spleen was correlated with platelets count (r = - 0.713, 0.392; p = 0.001, 0.012) and prothrombin time (r = 0.518, - 0.380; p = 0.001, 0.016). CONCLUSION: DTI metrics of spleen can predict and grade OV and correlated with laboratory biomarkers of portal hypertension.

Imaging of vascular cognitive impairment.

Vascular cognitive impairment (VCI) is a major health challenge and represents the second most common cause of dementia. We review the updated imaging classification and imaging findings of different subtypes of VCI. We will focus on the magnetic resonance imaging (MRI) markers of each subtype and highlight the role of advanced MR imaging sequences in the evaluation of these patients. Small vessel dementia appears as white matter hyperintensity, lacunae, microinfarcts, and microbleeds. Large vessel dementia includes strategic infarction and multi-infarction dementias. Hypoperfusion dementia can be seen as watershed infarcts and cortical laminar necrosis. Hemorrhagic dementia results from cerebral amyloid angiopathy and cortical superficial siderosis. Hereditary forms of VCI, caused by gene mutations such as CADASIL, should be suspected when dementia presents in young patients. Mixed dementia is seen in patients with Alzheimer's disease and the coexistence of cerebrovascular disease.

Role of diffusion-weighted imaging in prediction of nipple-areolar complex invasion by breast cancer.

THE AIM OF THIS WORK: The aim of this work was to estimate the role of diffusion-weighted imaging (DWI) in predicting malignant invasion of the nipple-areolar complex (NAC) by underlying breast cancer. MATERIAL AND METHODS: This prospective study included 70 female patients with breast cancer with a mean age of 45.8 years (range: 28-68). DWI of the breast was done for all patients. Apparent diffusion coefficient (ADC) maps were automatically constructed. The mean ADC values of NAC were independently measured by two observers who are experts in breast imaging and correlated with the results of histopathological examinations. RESULTS: Both observers found a significantly lower ADC value of malignant NAC invasion (n = 18) when compared with free NAC (n = 52), with mean ADC value for malignant NAC invasion was 0.86 ± 0.35 × 10-3 mm2/s and 0.84 ± 0.08 × 10-3 mm2/s for observer one and two respectively versus mean ADC value of 1.34 ± 0.25 × 10-3 mm2/s and 1.4 ± 0.26 × 10-3 mm2/s for free NAC by observer one and two respectively (P-value =0.001). Observer one found that a cutoff ADC value of 1.05 × 0-3 mm2/s can predict malignant NAC invasion with 0.975 AUC, 92.8% accuracy, 94.4% sensitivity, and 92.3% specificity. Observer two found that a cutoff ADC value of 0.95 × 10-3 mm2/s can predict malignant NAC invasion with 0.992 AUC, 95.7% accuracy, 88.9% sensitivity, and 98.1% specificity. CONCLUSION: DWI can predict malignant NAC invasion in patients with breast cancer.

Role of dynamic sleep MRI in obstructive sleep apnea syndrome.

PURPOSE: To identify obstruction sites of the upper airway during sleep in patients with obstructive sleep apnea syndrome (OSAS) under dynamic conditions and improve knowledge to guide surgical treatment and advancements. MATERIALS AND METHODS: The study included 15 patients (5 females and 10 males) who were diagnosed as having OSAS. Overall mean age was 40.2 years (± 7.01 years). All the patients underwent drug-induced sleep endoscopy (DISE) and dynamic sleep MRI. The presence, location, and direction of airway collapse were assessed. Dynamic MRI findings were correlated to DISE. Data of the site and direction of airway collapse were correlated with those of endoscopic findings and interobserver agreement was done. RESULTS: The dynamic images in sagittal section showed collapse of the upper airway at retropalatal level in 14 patients (93.33%) and at retroglossal level in seven patients (46.7%) and of these 14 patients; seven had combined retropalatal and retroglossal collapse. These findings were highly correlated with DISE findings with an excellent interobserver agreement for retropalatal and retroglossal levels (Kappa = 1 and 0.867, P value = 0.000), respectively. Objective measurements of the direction of collapse in axial dynamic sleep MRI images showed significant statistical correlation with endoscopic findings regarding retropalatal anteroposterior and circumferential collapse (Kappa = 0.58 and 0.52, P value = 0.02 and 0.03, respectively). CONCLUSION: Dynamic sleep MRI can reliably characterize the actual site of dynamic airway obstruction and has the potential of improving predictions of successful surgical outcomes in OSAS patients.

MR and CT imaging features of sino-nasal organized hematomas.

AIM: To describe the MR and CT imaging features of organized hematomas [OH]. METHODS: A retrospective analysis of MR imaging and CT of eight patients [6 male, 2 females; age range is 6-86 years] with pathological proven OH was performed. Routine contrast MR and CT scan were done for all patients, and diffusion-weighted imaging and dynamic contrast CT were done for only five patients. Imaging analysis was done for the signal intensity, the enhancement pattern at MR imaging, the ADC value at DWI, bone remodeling at CT, and the neo-vascularization at dynamic contrast CT. RESULTS: OH revealed T2 hypo-intense of the matrix in all patients with complete [n = 3] and incomplete [n = 5] marginal hypo-intensity rim. The lesions revealed a frond-like pattern of contrast enhancement of the central part of the lesion that associated with a peripheral rim of contrast enhancement. OH revealed unrestricted diffusion with high ADC value [1.7-2.5 × 10-3 cm2/s] in 5 patients. CT scan showed geographic bone remodeling and thinning of the nasal turbinates, and the sinus wall and contrast CT showed neo-vascularization with frond-like branching arteries of the central part of the lesions in five patients. CONCLUSION: We conclude that MR and CT imaging findings can help in the diagnosis of OH.

Multi-parametric arterial spin labeling and diffusion-weighted imaging in differentiation of metastatic from reactive lymph nodes in head and neck squamous cell carcinoma.

PURPOSE: To assess arterial spin labeling (ASL) and diffusion-weighted imaging (DWI) in the differentiation of metastatic from reactive lymph nodes (LNs) in head and neck squamous cell carcinoma (HNSCC). MATERIALS AND METHODS: Retrospective analysis of 113 LNs in 43 patients with HNSCC underwent ASL and DWI of the neck. The tumor blood flow (TBF) and apparent diffusion coefficient (ADC) of the cervical LNs were calculated. The final diagnosis of metastatic (n = 82) and reactive (n = 31) was proved with the pathological examination. RESULTS: The TBF of metastatic LNs (58.8 ± 10.2, 58.6 ± 8.5 mL/100 g/min) was significantly higher (p = 0.001) than the reactive LNs (23.2 ± 10.3, 28.2 ± 16.7 mL/100 g/min) for both observers, respectively. The ADC of metastatic LN (1.12 ± 0.07, 1.21 ± 0.07 × 10-3mm2/s) was significantly lower (p = 0.001) than reactive LN (1.41 ± 0.09, 1.44 ± 0.14 × 10-3mm2/s) for both observers, respectively. The threshold of TBF (> 39.5, 40.5 mL/100 g/min), ADC (≥ 1.31, 1.30 X10-3mm2/s) and combined parameters for both observers, respectively, used for differentiating metastatic from reactive LNs revealed an area under the curve of (0.94, 0.945), (0.90, 0.931), and (0.98, 0.989), an accuracy of (88.6%, 80.5%), (80.0%, 88.5%), and (94.3%, 98.2), respectively. CONCLUSION: Combined TBF and ADC are non-invasive imaging parameters that can play a role in differentiation metastatic from reactive LNs in patients with HNSCC.

Imaging of congenital cranial dysinnervation disorders: What radiologist wants to know?

We aim to review the imaging features of congenital cranial dysinnervation disorders. Characteristic imaging findings can define subtypes of these disorders through assessment of cranial nerves, extraocular muscles, orbital, and brain abnormalities. Duane retraction syndrome shows absent or hypoplasic 6th cranial nerve and preserved extraocular muscles (EOM). Mobius syndrome shows absent 7th and 6th cranial nerves, absence of facial colliculus, flattening of the dorsal aspect of the pons, hypoplasia of the pons and medulla, and flattening of the 4th ventricular floor. Congenital fibrosis of the extraocular muscles reveals unilateral or bilateral hypoplasia or aplasia of the 3rd cranial nerve, atrophy of superior rectus and levator palpebrae superioris muscles, and atrophy of the brainstem and cerebellar hemispheres. Horizontal gaze palsy and progressive scoliosis show characteristic split pons sign, butterfly medulla, absent facial colliculi, and spinal scoliosis. HOXA1 Mutations show a bilateral absence of 6th cranial nerves with the underdeveloped inner ear. Pontine Cap Tegmental Dysplasia shows ventral pontine hypoplasia, dorsal tegmental projection into the 4th ventricle, and variable cranial nerve deficits.