Investigation of the risk factors in the development of radionecrosis in patients with brain metastases undergoing stereotactic radiotherapy.

OBJECTIVE: To investigate the incidence, timing, and the factors predictors radionecrosis (RN) development in brain metastases (BMs) undergoing stereotactic radiotherapy (SRT). METHODS: The study evaluated 245 BMs who exclusively received SRT between 2010 and 2020. RN was detected pathologically or radiologically. RESULTS: The median of follow-up was 22.6 months. RN was detected in 18.4% of the metastatic lesions, and 3.3% symptomatic, 15.1% asymptomatic. The median time of RN was 22.8 months (2.5-39.5), and the rates at 6, 12, and 24 months were 16.8%, 41.4%, and 66%, respectively. Univariate analysis revealed that Graded Prognostic Assessment (P = .005), Score Index of Radiosurgery (P = .015), Recursive Partitioning Analysis (P = .011), the presence of primary cancer (P = .004), and localization (P = .048) significantly increased the incidence of RN. No significant relationship between RN and brain-gross tumour volume doses, planning target volume, fractionation, dose (P > .05). Multivariate analysis identified SIR > 6 (OR: 1.30, P = .021), primary of breast tumour (OR: 2.33, P = .031) and supratentorial localization (OR: 3.64, P = .025) as risk factors. CONCLUSIONS: SRT is used effectively in BMs. The incidence of RN following SRT is undeniably frequent. It was observed that the incidence rate increased as the follow-up period increased. We showed that brain-GTV doses are not predictive of RN development, unlike other publications. In study, a high SIR score and supratentorial localization were identified as factors that increased the risk of RN. ADVANCES IN KNOWLEDGE: RN is still a common complication after SRT. Symptomatic RN is a significant cause of morbidity. The causes of RN are still not clearly identified. In many publications, brain dose and volumes have been found to be effective in RN. But, with this study, we found that brain dose volumes and fractionation did not increase the incidence of RN when brain doses were taken into account. The most important factor in the development of RN was found to be related to long survival after SRT.

Coexistence of longitudinally extensive transverse myelitis and diffuse midline glioma in the brainstem in an adolescent boy with acute flaccid paralysis.

We present the case of a previously healthy 13-year-old boy who was admitted to the emergency department with acute flaccid paralysis. Magnetic resonance imaging revealed radiological evidence of longitudinally extensive transverse myelitis. Additionally, homogeneous T2 signal increase was observed in the pons and medulla oblongata, initially indicating brainstem encephalitis. Subsequent evaluations confirmed a coexistence of diffuse midline glioma (DMG) in the brain stem alongside acute transverse myelitis (ATM). Children with ATM generally have a more favorable prognosis than adults. However, despite the implementation of advanced treatment methods, the patient's quadriplegia did not improve and resulted in spinal cord sequela atrophy. DMG exhibits an aggressive growth pattern and lacks a known curative treatment. This case represents an exceedingly rare synchronous occurrence of aggressive conditions, underscoring the importance of raising awareness among physicians. Furthermore, we aim to discuss the radiologic differential diagnosis, as this is the first documented instance in the literature.

Predictors of local control after robotic stereotactic radiotherapy for brain metastases: 10-years-experience after Cyberknife installation.

BACKGROUND: To evaluate the factors influencing brain metastases (BM) local control (LC) after stereotactic radiotherapy (SRT). METHODS: Between 2010 and 2020, a cohort of 145 patients (246 BM) treated consecutively with robotic radiosurgery was analysed. RESULTS: Median age was 61 years (range, 29-90 years). Median radiological follow-up of the lesions was 21.7 months (range, 3-115 months). The mean overall survival and LC were 33.0 and 82.7 months, respectively. On univariate analysis, sex, primary cancer site, histological type, use of systemic steroids, maximum diameter, volume, early MRI response, isodose line, number of fractions, BED10 value, and BED10 value proportional to volume and maximum diameter were significant factors for LC. On multivariate analysis, female sex (hazard ratio [HR]: 2.10 P: 0.035), adenocarcinoma histology (HR: 6.54 P: 0.001), no steroid use (HR: 3.60 P: 0.001), maximum diameter (≤1 cm) (HR: 2.64 P: 0.018), complete response of lesion at first follow-up MRI compared to stable or progressive disease (HR: 4.20, P = 0.024; HR: 19.15, P < 0.001), isodose line (≥90%) (HR: 2.00 P: 0.036), and tumour volume (PTV ≤2 cc) (HR: 5.19 P: 0.001) were independent factors improving LC. CONCLUSIONS: SRT is an effective treatment for patients with a limited number of BM with a high LC rate. There are many factors related to the patient, tumour, and radiotherapy plan that have an impact on LC after SRT in brain metastases. These results warrant further investigation in a prospective setting.

Apparent diffusion coefficient (ADC) measurements and morphometric evaluation of the cranium in age-matched children with central precocious puberty.

OBJECTIVES: Central precocious puberty (CPP) is one of the common reasons for referral to pediatric endocrinology. Magnetic resonance imaging (MRI) is used to rule out intracranial pathologies. However, there is insufficient information in the literature about bone marrow abnormalities on MRI in CPP cases. The aim of this study was to evaluate the apparent diffusion coefficient (ADC) values obtained from bone marrow diffusion weight images (DWI) of cranial bone structures and the status of sphenooccipital synchondrosis (SOS) in CPP. METHODS: MRI data from 6-to 9-year-old girls with CPP and a healthy control group were evaluated. Anthropometric data, FSH, LH, and oestradiol tests were recorded, and the relationship between SOS status, DWI-ADC values of the clivus, parietal bone, and occipital protuberance were compared. RESULTS: The study included 146 girls, 79 CPP, and 67 healthy aged 6-9 years (median: 8 (2)). The diagnosis age was 8.30 ± 0.8 years. The ADC values were significantly lower on CPP than normal controls (p=<0.05). In the CPP group, pattern 1 was found at 2 % (n=2), pattern 2 at 3.5 % (n=3), and pattern 3 at 3.5 % (n=3) in clivus sphenooccipital synchondrosis. There was no correlation between the mean parietal, occipital, and clivus ADC values and any variable (p>0.05). CONCLUSIONS: DWI-MRI ADC analysis can be used as a quantitative radiological marker for early detection of CPP, even before changes in sphenooccipital synchondrosis.

Role of apparent diffusion coefficient measurement in differentiating histological subtypes of brain metastasis of lung cancer.

OBJECTIVE: The aim of this study was to investigate the role of apparent diffusion coefficient of diffusion-weighted imaging in differentiating histological subtypes of brain metastasis of lung cancer. METHODS: Diffusion-weighted imaging of 158 patients (mean age: 61.2±10.68 years) with brain metastasis of lung cancer (36 small cell lung cancer and 122 non-small cell lung cancer) were retrospectively evaluated. The minimum and mean apparent diffusion coefficient values of the metastasis, apparent diffusion coefficient of edema around the metastasis, and apparent diffusion coefficient of contralateral brain parenchyma were measured. Normalized apparent diffusion coefficient was calculated by proportioning the mean apparent diffusion coefficient of the metastasis to the apparent diffusion coefficient of the contralateral brain parenchyma. Minimum and mean apparent diffusion coefficient of the metastasis, apparent diffusion coefficient of edema around metastasis, and normalized apparent diffusion coefficient were compared between small cell lung cancer and non-small cell lung cancer metastases. RESULTS: Minimum apparent diffusion coefficient, mean apparent diffusion coefficient, and normalized apparent diffusion coefficient values of small cell lung cancer metastases (0.43±0.19×10-3mm2/s, 0.63±0.20×10-3mm2/s, and 0.81 [0.55-1.44], respectively) were significantly lower than those of non-small cell lung cancer metastases (0.71±0.26×10-3mm2/s, 0.93±0.29×10-3mm2/s, and 1.30 [0.60-3.20], respectively; p<0.001). Mean apparent diffusion coefficient of edema of small cell lung cancer metastases (1.21±0.28×10-3mm2/s) was significantly lower than that of non-small cell lung cancer metastases (1.39±0.26×10-3mm2/s, p=0.020). The best cutoff values of minimum apparent diffusion coefficient, mean apparent diffusion coefficient, normalized apparent diffusion coefficient, and apparent diffusion coefficient of edema for the differentiation of small cell lung cancer and non-small cell lung cancer were found to be 0.56×10-3mm2/s, 0.82×10-3mm2/s, 1.085, and 1.21×10-3mm2/s, respectively. The area under the receiver operating characteristic curve, sensitivity, and specificity values were, respectively, 0.812, 80.6, and 73.8% for minimum apparent diffusion coefficient; 0.825, 91.7, and 61.5% for mean apparent diffusion coefficient; 0.845, 80.6, and 73.8% for normalized apparent diffusion coefficient; and 0.698, 75.0, and 67.7% for apparent diffusion coefficient of edema. CONCLUSIONS: Minimum apparent diffusion coefficient, mean apparent diffusion coefficient, normalized apparent diffusion coefficient, and apparent diffusion coefficient of edema around metastasis can differentiate histological subtypes of brain metastasis of lung cancer.

Role of apparent diffusion coefficient measurement in differentiating histological subtypes of brain metastasis of lung cancer

SUMMARY OBJECTIVE: The aim of this study was to investigate the role of apparent diffusion coefficient of diffusion-weighted imaging in differentiating histological subtypes of brain metastasis of lung cancer. METHODS: Diffusion-weighted imaging of 158 patients (mean age: 61.2±10.68 years) with brain metastasis of lung cancer (36 small cell lung cancer and 122 non-small cell lung cancer) were retrospectively evaluated. The minimum and mean apparent diffusion coefficient values of the metastasis, apparent diffusion coefficient of edema around the metastasis, and apparent diffusion coefficient of contralateral brain parenchyma were measured. Normalized apparent diffusion coefficient was calculated by proportioning the mean apparent diffusion coefficient of the metastasis to the apparent diffusion coefficient of the contralateral brain parenchyma. Minimum and mean apparent diffusion coefficient of the metastasis, apparent diffusion coefficient of edema around metastasis, and normalized apparent diffusion coefficient were compared between small cell lung cancer and non-small cell lung cancer metastases. RESULTS: Minimum apparent diffusion coefficient, mean apparent diffusion coefficient, and normalized apparent diffusion coefficient values of small cell lung cancer metastases (0.43±0.19×10−3mm2/s, 0.63±0.20×10−3mm2/s, and 0.81 [0.55-1.44], respectively) were significantly lower than those of non-small cell lung cancer metastases (0.71±0.26×10−3mm2/s, 0.93±0.29×10−3mm2/s, and 1.30 [0.60-3.20], respectively; p<0.001). Mean apparent diffusion coefficient of edema of small cell lung cancer metastases (1.21±0.28×10−3mm2/s) was significantly lower than that of non-small cell lung cancer metastases (1.39±0.26×10−3mm2/s, p=0.020). The best cutoff values of minimum apparent diffusion coefficient, mean apparent diffusion coefficient, normalized apparent diffusion coefficient, and apparent diffusion coefficient of edema for the differentiation of small cell lung cancer and non-small cell lung cancer were found to be 0.56×10−3mm2/s, 0.82×10−3mm2/s, 1.085, and 1.21×10−3mm2/s, respectively. The area under the receiver operating characteristic curve, sensitivity, and specificity values were, respectively, 0.812, 80.6, and 73.8% for minimum apparent diffusion coefficient; 0.825, 91.7, and 61.5% for mean apparent diffusion coefficient; 0.845, 80.6, and 73.8% for normalized apparent diffusion coefficient; and 0.698, 75.0, and 67.7% for apparent diffusion coefficient of edema. CONCLUSIONS: Minimum apparent diffusion coefficient, mean apparent diffusion coefficient, normalized apparent diffusion coefficient, and apparent diffusion coefficient of edema around metastasis can differentiate histological subtypes of brain metastasis of lung cancer.

Microstructural white matter abnormalities in hypothyroidism evaluation with diffusion tensor imaging tract-based spatial statistical analysis.

PURPOSE: Hypothyroidism is presented in a wide range from neuropsychiatric problems including depression, memory and cognitive disorders to poor motor coordination. Against the background of morphologic, functional and molecular changes on the white and grey matter of the brain, we aimed to investigate the effects of hypothyroidism on white matter (WM) integrity using tract-based spatial statistics (TBSS). METHODS: Eighteen patients with hyperthyroidism and 14 age-sex-matched healthy control subjects were included in this study. TBSS was used in the diffusion tensor imaging study for whole-brain voxel wise analysis of fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD) and radial diffusivity (RD) of WM. RESULTS: When compared to the control group, the whole brain TBSS revealed extensive reductions of FA in the supratentorial WM including corticospinal tract, posterior limb of the internal capsule (PLIC), uncinate fasciculus, inferior longitudinal fasciculus (p < 0.005). The ROI analyses showed RD increment of superior longitudinal fasciculus, AD decrement of cingulum (CIN), external capsule, PLIC and corpus callosum (CC) in patients with hypothyroidism (p < 0.005). Autoimmune and non-autoimmune hypothyroidism patient subgroups showed a significant difference in terms of hippocampus FA, CIN MD, CC MD, CC AD, CIN RD, SLF RD, CC RD (p < 0.005). CIN FA values showed a negative correlation with the Beck Depression Inventory (p = 0.007, r = - 852). CONCLUSIONS: These preliminary results of TBSS analyses represented FA and AD decrement, and RD increment in several WM tracts and indicates the demyelination process underlying pathophysiology of clinical aspects of hypothyroidism.

Olfactory Bulb Microstructural Changes in Patients With Nasal Septum Deviation.

OBJECTIVE: The aim of this study is to assess the microstructural changes to the olfactory bulb (OB) in patients with nasal septum deviation (NSD) using diffusion tensor imaging and to research the association between these changes and the degree of NSD. METHODS: Ninety-six patients with NSD (46 males, 50 females) who received diffusion tensor imaging were assessed by 2 independent readers. The patients were separated into 3 groups according to the NSD angle. The fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values of the ipsilateral and contralateral OB were measured in all NSD patients by region of interest. RESULTS: According to deviation side, there was significant difference between the right (R) and left (L) OB FA and ADC values across the 3 groups. In patients with left- and right- sided NSD, FA and ADC values for the left and right OB were significantly different between groups 1 and 3, and groups 2 and 3. There was negative correlation between L-FA (r = -0.481, P = 0.001; r = -0.496, P = 0.001) and R-FA (r = -0.705, P = 0.001; r = -0.286, P = 0.02) versus age and deviation angle. However, there was positive correlation between L-ADC versus age and deviation angle (r = 0.493, P = 0.001; r = 0.482, P = 0.001), as well as positive correlation between R-ADC versus age (r = 0.646, P = 0.001). CONCLUSION: This is the first study showing ADC increase and FA decrease associated with axonal damage and microstructural integrity loss based on the side of deviation in NSD patients. It has also shown that this abnormality is directly proportional with NSD degree.

Multiparametric MRI in differentiating solitary brain metastasis from high-grade glioma: diagnostic value of the combined use of diffusion-weighted imaging, dynamic susceptibility contrast imaging, and magnetic resonance spectroscopy parameters.

OBJECTIVE: The purpose of this study was to determine whether the combined use of diffusion weighted imaging (DWI), magnetic resonance spectroscopy (MRS), and dynamic susceptibility contrast imaging (DSCI) parameters could provide a more accurate diagnosis in the differentiation of high-grade glioma (HGG) from solitary brain metastasis (SBM) in the enhancing tumour and in the peritumoural region. MATERIALS AND METHODS: Fifty-six patients who received DWI, DSCI, and MRS before surgery were assessed. In differentiating SBM from HGG, the cutoff values of the DWI-apparent diffusion coefficient (ADCmin, ADCmax, and ADCmean), DSCI-relative cerebral blood volume (rCBV), and MRS-Cho/Cr, Cho/NAA, and NAA/Cr parameters for the peritumoural region were determined with ROC. The combined ROC curve was used for the different combinations of the peritumoural region DWI, DSCI, and MRS parameters in differentiating between the two tumours, and the best model combination was formed. All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional research committee and with the 1964 Helsinki Declaration and its later amendments. This study was approved by the Institutional Review Board at our institutes. RESULTS: In the enhancing tumour, all the parameters except NAA/Cr (P = 0.024) exhibited no statistical difference in differentiating between these two groups (P > 0.05). AUC values for ADCmin, ADCmax, ADCmean, rADCmin, rADCmax, rADCmean, rCBV, Cho/Cr, Cho/NAA, and NAA/Cr parameters in the peritumoural region in differentiating SBM from HGG were 0.860, 0.822, 0.848, 0.822, 0.801, 0.822, 0.906, 0.851, 0.903, and 0.784, respectively. In differentiating HGG from SBM, the best model consisted of the combination of peritumoural ADCmin, rCBV, and Cho/NAA parameters. AUC values were 0.970. CONCLUSIONS: The combination of peritumoural region ADCmin, rCBV, and Cho/NAA parameters can help in differentiating SBM from HGG, with a diagnostic accuracy of 97%.

Association between facial nerve second genu angle and facial canal dehiscence in patients with cholesteatoma: evaluation with temporal multidetector computed tomography and surgical findings / Associação entre o ângulo do segundo joelho do nervo facial e deiscência do canal facial em pacientes com colesteatoma: avaliac¸ão do osso temporal por tomografia com multidetectores e pelos achados cirúrgicos

Abstract Introduction: Otitis media, mastoiditis or the pressure effect of tumorous lesions such as cholesteatoma can be the cause of facial canal dehiscence and facial nerve paralysis. The most common segment involved in dehiscence is the tympanic segment and the second most common is the lateral aspect of the facial canal in the oval window area. Objective: To determine the prevalence of the facial canal dehiscence and the relationship between the angle at the second genu of the facial nerve and facial canal dehiscence. Methods: We evaluated the surgical findings in 113 patients who underwent surgery for cholesteatoma. Facial canal dehiscence was detected in 62 of the 113 patients. Patients were divided into two groups: Group 1, with dehiscence of the facial canal and Group 2, without dehiscence of the facial canal. Results: The mean angles at the second genu of the facial nerve in Groups 1 and 2 were 117.8º ± 9.63º and 114º ± 9.9º, respectively. There was a statistically significant difference between the mean angles at the second genu for the two groups (p = 0.04). Conclusion: In patients with dehiscence of the facial canal, the angle at the second genu was found to be wider than those without dehiscence.

Resumo Introdução: Otite média, mastoidite ou a compressão por lesões tumorais como o colesteatoma podem ser a causa da deiscência do canal facial e paralisia do nervo facial. A deiscência ocorre mais frequentemente no segmento timpânico, seguido do aspecto lateral do canal facial na área da janela oval. Objetivo: Determinar a prevalência da deiscência do canal facial e sua relação com o ângulo no segundo joelho do nervo facial. Método: Avaliamos os achados cirúrgicos para detecção de deiscência do canal facial em 113 pacientes submetidos à cirurgia de colesteatoma. A deiscência do canal facial foi observada em 62. Os pacientes foram divididos em dois grupos: Grupo 1, com deiscência do canal facial, e Grupo 2, sem deiscência do canal facial. Resultados: Os ângulos médios no segundo joelho do nervo facial nos grupos 1 e 2 foram 117,8º ± 9,63º e 114º ± 9,9º, respectivamente. Houve diferença estatisticamente significante entre os ângulos médios no segundo joelho para os dois grupos (p = 0,04). Conclusão: Em pacientes com deiscência no canal facial, foi observado que o ângulo do segundo joelho era maior do que naqueles sem deiscência.

Association between facial nerve second genu angle and facial canal dehiscence in patients with cholesteatoma: evaluation with temporal multidetector computed tomography and surgical findings.

INTRODUCTION: Otitis media, mastoiditis or the pressure effect of tumorous lesions such as cholesteatoma can be the cause of facial canal dehiscence and facial nerve paralysis. The most common segment involved in dehiscence is the tympanic segment and the second most common is the lateral aspect of the facial canal in the oval window area. OBJECTIVE: To determine the prevalence of the facial canal dehiscence and the relationship between the angle at the second genu of the facial nerve and facial canal dehiscence. METHODS: We evaluated the surgical findings in 113 patients who underwent surgery for cholesteatoma. Facial canal dehiscence was detected in 62 of the 113 patients. Patients were divided into two groups: Group 1, with dehiscence of the facial canal and Group 2, without dehiscence of the facial canal. RESULTS: The mean angles at the second genu of the facial nerve in Groups 1 and 2 were 117.8°±9.63° and 114°±9.9°, respectively. There was a statistically significant difference between the mean angles at the second genu for the two groups (p=0.04). CONCLUSION: In patients with dehiscence of the facial canal, the angle at the second genu was found to be wider than those without dehiscence.

The diagnostic value of using combined MR diffusion tensor imaging parameters to differentiate between low- and high-grade meningioma.

OBJECTIVE: The purpose of this study was to examine whether the combined use of MR diffusion tensor imaging (DTI) parameters [DTI-apparent diffusion coefficient (ADC), fractional anisotropy (FA), axial diffusivity (AD), and radial diffusivity (RD)] could provide a more accurate diagnosis in differentiating between low-grade and atypical/anaplastic (high-grade) meningioma. METHODS: Pathologically proven 45 meningioma patients [32 low-grade, 13 high-grade (11 atypical and 2 anaplastic)] who had received DTI before surgery were assessed retrospectively by 2 independent observers. For each lesion, MR DTI parameters (ADCmin, ADCmax, ADCmean, FA, AD, and RD) and ratios (rADCmin, rADCmax, rADCmean, rFA, rAD, and rRD) were calculated. When differentiating between low- and high-grade meningioma, the optimum cutoff values of all MR DTI parameters were determined by using receiver operating characteristic (ROC) analysis. Area under the curve (AUC) was measured with combined ROC analysis for different combinations of MR DTI parameters in order to identify the model combination with the best diagnostic accuracy in differentiation between low and high-grade meningioma. RESULTS: Although the ADCmin, ADCmax, ADCmean, AD, RD, rADCmin, rADCmax, rADCmean, rAD, and rRD values of high-grade meningioma were significantly low (p = 0.007, p = 0.045, p = 0.035, p = 0.045, p = 0.003, p = 0.02, p = 0.03, p = 0.03, p = 0.045, and p = 0.01, respectively), when compared with low-grade meningioma, their FA and rFA values were significantly high (p = 0.007 and p = 0.01, respectively). For all MR DTI parameters, the highest individual distinctive power was RD with AUC of 0.778. The best diagnostic accuracy in differentiating between low- and high-grade meningioma was obtained by combining the ADCmin, RD, and FA parameters with 0.962 AUC. CONCLUSION: This study shows that combined MR DTI parameters consisting of ADCmin, RD, and FA can differentiate high-grade from low-grade meningioma with a diagnostic accuracy of 96.2%. Advances in knowledge: To the best of our knowledge, this is the first study reporting that a combined use of all MR DTI parameters provides higher diagnostic accuracy for the differentiation of low- from high-grade meningioma. Our study shows that any of the model combinations was superior to use of any individual MR DTI parameters for differentiation between low and high-grade meningioma. A combination of ADCmin, RD, and FA was found to be the best model for differentiating low-grade from high-grade meningioma and sensitivity, specificity, and AUC values were found to be 92.3%, 100%, and 0.96, respectively. Thus, a combination of MR DTI parameters can provide more accurate diagnostic information when differentiation between low and high-grade meningioma.

Magnetic Resonance Imaging of Intracranial Hypotension: Diagnostic Value of Combined Qualitative Signs and Quantitative Metrics.

OBJECTIVE: The aim of this study was to investigate whether the use of combination quantitative metrics (mamillopontine distance [MPD], pontomesencephalic angle, and mesencephalon anterior-posterior/medial-lateral diameter ratios) with qualitative signs (dural enhancement, subdural collections/hematoma, venous engorgement, pituitary gland enlargements, and tonsillar herniations) provides a more accurate diagnosis of intracranial hypotension (IH). METHODS: The quantitative metrics and qualitative signs of 34 patients and 34 control subjects were assessed by 2 independent observers. Receiver operating characteristic (ROC) curve was used to evaluate the diagnostic performance of quantitative metrics and qualitative signs, and for the diagnosis of IH, optimum cutoff values of quantitative metrics were found with ROC analysis. Combined ROC curve was measured for the quantitative metrics, and qualitative signs combinations in determining diagnostic accuracy and sensitivity, specificity, and positive and negative predictive values were found, and the best model combination was formed. RESULTS: Whereas MPD and pontomesencephalic angle were significantly lower in patients with IH when compared with the control group (P < 0.001), mesencephalon anterior-posterior/medial-lateral diameter ratio was significantly higher (P < 0.001). For qualitative signs, the highest individual distinctive power was dural enhancement with area under the ROC curve (AUC) of 0.838. For quantitative metrics, the highest individual distinctive power was MPD with AUC of 0.947. The best accuracy in the diagnosis of IH was obtained by combination of dural enhancement, venous engorgement, and MPD with an AUC of 1.00. CONCLUSIONS: This study showed that the combined use of dural enhancement, venous engorgement, and MPD had diagnostic accuracy of 100 % for the diagnosis of IH. Therefore, a more accurate IH diagnosis can be provided with combination of quantitative metrics with qualitative signs.

MDCT of the temporal bone and audiological findings of pediatric acquired cholesteatoma.

Cholesteatoma is a benign epithelial lesion affecting the middle ear and/or mastoid process, causing otorrhea and hearing loss. Here, we retrospectively evaluated the temporal multidetector computed tomography and audiological findings of acquired cholesteatoma in children. Forty-three patients younger than 18 years old with middle ear acquired cholesteatoma were evaluated with regard to their clinical symptoms, temporal multidetector computed tomography findings, and audiometry results. The multidetector computed tomography findings were classified according to the site-ossicle-complication classification, and the relationships between the clinical, radiological, and audiological findings were evaluated. Only one patient had pars tensa cholesteatoma, and the remaining had attic cholesteatoma. The most common site-ossicles-complication classifications were S4 (acquired cholesteatoma involving four sites), O1 (involving one ossicle), and C0 (no complications), and the most common complaint was hearing loss, followed by otorrhea. There were no statistically significant relationships between the site of involvement and ossicle involvement. In addition, there were no statistically significant differences according to the S classification in either the air conduction or air-bone-gap levels; however, these levels differed statistically significantly with increasing ossicle involvement. Early diagnosis and treatment are essential to prevent hearing loss and serious complications in cases of acquired cholesteatoma. Therefore, it is important to evaluate the temporal multidetector computed tomography and audiological findings to accurately diagnose acquired cholesteatoma in children.

A Rare Concha Variation: Coronal Cleft.

Nasal turbinates are embryologically derived from a series of outgrowths from the foetal lateral nasal wall. These outgrowths form a series of ridges, referred to as "ethmoturbinals" and have several vital functions. Several different turbinate variations have been reported so far. The authors presented 3 patients of coronal clefted concha who were diagnosed with magnetic resonance imaging. Computed tomography scans and nasal endoscopic examinations are also performed subsequently. These patients are the first coronal clefted concha cases in the literature and also the first radiological study defining concha cleft. This shows paucity of data documenting variations in the lateral nasal wall. Understanding the anatomy and the anatomic variations of the nasal cavity and nasal turbinates is critical to guide the procedure due to its close proximity to vital structures such as orbita and skull base, especially for functional endoscopic sinus surgery that is a widely used technique nowadays.

Efficiency of B-mode Ultrasound and Strain Elastography in Differentiating Between Benign and Malignant Cervical Lymph Nodes.

PURPOSE: The purpose of this study was to evaluate the diagnostic accuracy and efficiency of ultrasonography (US), especially when combined with strain elastography (SE), in differentiating between benign and malignant cervical lymph nodes (LNs). METHODS: Forty-one LNs were examined by B-mode US, power Doppler US, and SE. The following imaging features were analyzed: shape, echogenicity, echogenic hilum, calcification, intranodal vascular pattern, elasticity scores (5 categories), and strain ratio. The average strain ratio was calculated as the mean strain of the adjacent sternocleidomastoid muscle divided by the mean strain of the target LN. The results of the US and SE features were compared with the histopathologic findings. RESULTS: The imaging features that were significantly associated with malignant LNs were an increased short-to-long axis diameter ratio, abnormal or absence of hilum, microcalcification, type 2-3-4 vascularity, 3-4-5 elasticity scores, and a high level of strain ratio (P < 0.05). The cutoff value of the strain index was detected as 1.18. According to this, there was a significant difference (P = 0.004) in the strain index between benign and malignant LNs. CONCLUSIONS: Strain elastography is useful in differentiating between benign and malignant cervical LNs, thereby informing decisions to perform a biopsy and/or surgery, and facilitating follow-up.

Spontaneous Epidural Pneumocephalus.

Spontaneous epidural pneumocephalus is a rare condition. The authors reported a 35-year-old male patient with tinnutus, dull headache, and swelling on his head. Patient had a history of head trauma and skull fracture from when he was 5 years old. Cranial computed tomography revealed increase in pneumatization of right mastoid air cells and large epidural air in temporoparietal region. Inner table of right temporal bone got thinner, causing communication of mastoid air cells with epidural space. Epidural air had septations and exerted mass effect on the right parietal lobe with minimal midline shift. Thinning of also right parietal bone caused extension of epidural air into the right parietal subcutaneous tissue and hence subcutaneous swelling. There was no obvious fracture line. Spontaneous epidural pneumocephalus is extremely rare condition that may cause severe complications. There are several etiologic factors. Head trauma can be the eliciting factor in the authors' patient. It is important to be familiar with its presentation and imaging findings to make early diagnosis and treatment.

Magnetic Resonance Imaging Evidence of Varicella Zoster Virus Polyneuropathy: Involvement of the Glossopharyngeal and Vagus Nerves Associated With Ramsay Hunt Syndrome.

The involvement of lower cranial nerve palsies is less frequent in Ramsay Hunt syndrome caused by varicella zoster virus (VZV). The authors report 1 of extremely rare patients of radiologically proven polyneuropathy of VZV infection with magnetic resonance imaging findings of VII, IX, and X cranial nerve involvement is a 62-year-old female patient, who initially presented with Ramsay Hunt syndrome. Varicella zoster virus infection should be considered even in patients who show unilateral palsy of the lower cranial nerves associated with laryngeal paralysis. Thin-section T2W and T1W images with a contrast agent should be added to the imaging protocol to show the subtle involvement.