Evaluation of respiratory bronchiolitis nodules with maximum intensity projection images.

OBJECTIVE: Respiratory bronchiolitis is a disease associated with heavy smoking. Computed tomography in this disease often shows symmetrical and bilaterally ill-defined circumscribed centriacinar micronodular involvement in the upper-middle lobes. The maximum intensity projection method is a kind of image processing method and provides a better evaluation of nodules and vascular structures. Our study aimed to show whether maximum intensity projection images increase the diagnostic accuracy in the detection of micronodules in respiratory bronchiolitis. METHODS: Two radiologists with different experiences (first reader: 10-year radiologist with cardiothoracic radiology experience and second reader: nonspecific radiologist with 2 years of experience) reviewed images of patients whose respiratory bronchiolitis diagnosis was supported by clinical findings. The evaluation was done independently of each other. Both conventional computed tomography images and maximum intensity projection images of the same patients were examined. The detection rates on conventional computed tomography and maximum intensity projection images were then compared. RESULTS: A total of 53 patients were evaluated, of whom 48 were men and 5 were women. The first reader detected centriacinar nodules in 42 (79.2%) patients on conventional computed tomography and centriacinar nodules in all 53 (100%) patients on maximum intensity projection images. The second reader detected centriacinar nodules in 12 (22.6%) patients on conventional computed tomography images and in 48 (90.6%) patients on maximum intensity projection images. For the less experienced reader, the detection rate of micronodules in respiratory bronchiolitis in maximum intensity projection images increased statistically significantly (p<0.001). CONCLUSION: Maximum intensity projection images in respiratory bronchiolitis increase the detectability of micronodules independently of the experience of the radiologist.

Role of contrast agent in evaluation of periprostatic invasion in prostate cancer.

Objectives: Our study aims to demonstrate the detection of invasion by biparametric prostate MRI (bpMRI). Materials and methods: The cases whose histopathological diagnosis was prostate cancer (PCa) and whose mpMRI report was reported as PIRADS 4 and 5 were evaluated retrospectively by two radiologists with different prostate imaging experiences. The images were grouped into two data sets. Dataset-1 was bpMRI, and dataset-2 was mpMRI. Two radiologists first evaluated dataset-1 independently of each other, and 1 month later, dataset-2. They recorded whether there was an invasion and where it was seen in the patients. Then, the results were compared. Results: A total of 75 patients were included in the study. Periprostatic invasion was detected in 33 of the patients. Both the 1st reader and the 2nd reader image detected all the cases with invasion (100%) separately between dataset-1 and set-2. Compatibility for image dataset-1 and dataset-2 between both readers was observed to be excellent. Conclusions: There is no need to use contrast agent to evaluate periprostatic invasion and to have an idea about local staging in PCa patients.

Objetivo: Nuestro estudio tiene como objetivo demostrar la detección de la invasión por resonancia magnética biparamétrica de próstata (BPMRI). Material y métodos: Los casos cuyo diagnóstico histopatológico fue PCA y cuyo informe MPMRI se informó como Pirads 4 y 5 fueron evaluados retrospectivamente por dos radiólogos con diferentes experiencias de imágenes de próstata. Las imágenes se agruparon en dos conjuntos de datos. DataSet-1 fue BPMRI, DataSet-2 fue MPMRI. Dos radiólogos evaluaron por primera vez el conjunto de datos 1 independientemente el uno del otro, y 1 mes después, el conjunto de datos-2. Registraron si había una invasión y dónde se vio en los pacientes. Luego se compararon los resultados. Resultados: Se incluyeron un total de 75 pacientes en el estudio. La invasión periprostática se detectó en 33 de los pacientes. Tanto el primer lector como la imagen del segundo lector detectaron todos los casos con invasión (100%) por separado entre el conjunto de datos-1 y el set-2. Se observó que la compatibilidad para el conjunto de datos de imágenes-1 y el conjunto de datos entre ambos lectores era excelente. Conclusiones: No es necesario usar el agente de contraste para evaluar la invasión periprostática y tener una idea sobre la puesta en escena local en pacientes con PCA.

Diagnostic efficacy of diffusion-weighted imaging and semiquantitative and quantitative dynamic contrast-enhanced magnetic resonance imaging in salivary gland tumors.

BACKGROUND: Increased use of functional magnetic resonance imaging (MRI) methods such as diffusion-weighted imaging (DWI) and dynamic contrast-enhanced (DCE) MRI consisting of sequential contrast series, allows us to obtain more information on the microstructure, cellularity, interstitial distance, and vascularity of tumors, which has increased the discrimination power for benign and malignant salivary gland tumors (SGTs). In the last few years, quantitative DCE MRI data containing T1 perfusion parameters (Ktrans, Kep and Ve), were reported to contribute to the differentiation of benign or malignant subtypes in SGTs. AIM: To evaluate the diagnostic efficacy of DWI and semiquantitative and quantitative perfusion MRI parameters in SGTs. METHODS: Diffusion MRI [apparent diffusion coefficient (ADC) value] with a 1.5 T MR machine, semiquantitative perfusion MRI [time intensity curve (TIC) pattern], and quantitative perfusion MRI examinations (Ktrans, Kep and Ve) of 73 tumors in 67 patients with histopathological diagnosis performed from 2017 to 2021 were retrospectively evaluated. In the ADC value and semiquantitative perfusion MRI measurements, cystic components of the tumors were not considered, and the region of interest (ROI) was manually placed through the widest axial section of the tumor. TIC patterns were divided into four groups: Type A = Tpeak > 120 s; type B = Tpeak ≤ 120 s, washout ratio (WR) ≥ 30%; type C = Tpeak ≤ 120 s, WR < 30%; and type D = flat TIC. For the quantitative perfusion MRI analysis, a 3D ROI was placed in the largest solid component of the tumor, and the Ktrans, Kep and Ve values were automatically generated. RESULTS: The majority of SGTs were located in the parotid glands (86.3%). Of all the SGTs, 68.5% were benign and 31.5% were malignant. Significant differences were found for ADC values among pleomorphic adenomas (PMAs), Warthin's tumors (WTs), and malignant tumors (MTs) (P < 0.001). PMAs had type A and WTs had type B TIC pattern while the vast majority of MTs and other benign tumors (OBTs) (54.5% and 45.5%, respectively) displayed type C TIC pattern. PMAs showed no washout, while the highest mean WR was observed in WTs (59% ± 11%). Ktrans values of PMAs, WTs, OBTs, and MTs were not significantly different. Kep values of PMAs and WTs were significantly different from those of OBTs and MTs. Mean Ve value of WTs was significantly different from those of PMAs, OBTs, and MTs (P < 0.001). CONCLUSION: The use of quantitative DCE parameters along with diffusion MRI and semiquantitative contrast-enhanced MRI in SGTs could improve the diagnostic accuracy.

Evaluation of respiratory bronchiolitis nodules with maximum intensity projection images

SUMMARY OBJECTIVE: Respiratory bronchiolitis is a disease associated with heavy smoking. Computed tomography in this disease often shows symmetrical and bilaterally ill-defined circumscribed centriacinar micronodular involvement in the upper-middle lobes. The maximum intensity projection method is a kind of image processing method and provides a better evaluation of nodules and vascular structures. Our study aimed to show whether maximum intensity projection images increase the diagnostic accuracy in the detection of micronodules in respiratory bronchiolitis. METHODS: Two radiologists with different experiences (first reader: 10-year radiologist with cardiothoracic radiology experience and second reader: nonspecific radiologist with 2 years of experience) reviewed images of patients whose respiratory bronchiolitis diagnosis was supported by clinical findings. The evaluation was done independently of each other. Both conventional computed tomography images and maximum intensity projection images of the same patients were examined. The detection rates on conventional computed tomography and maximum intensity projection images were then compared. RESULTS: A total of 53 patients were evaluated, of whom 48 were men and 5 were women. The first reader detected centriacinar nodules in 42 (79.2%) patients on conventional computed tomography and centriacinar nodules in all 53 (100%) patients on maximum intensity projection images. The second reader detected centriacinar nodules in 12 (22.6%) patients on conventional computed tomography images and in 48 (90.6%) patients on maximum intensity projection images. For the less experienced reader, the detection rate of micronodules in respiratory bronchiolitis in maximum intensity projection images increased statistically significantly (p<0.001). CONCLUSION: Maximum intensity projection images in respiratory bronchiolitis increase the detectability of micronodules independently of the experience of the radiologist.

Advanced magnetic resonance imaging findings in salivary gland tumors.

Salivary gland tumors (SGTs) make up a small portion (approximately 5%) of all head and neck tumors. Most of them are located in the parotid glands, while they are less frequently located in the submandibular glands, minor salivary glands or sublingual gland. The incidence of malignant or benign tumors (BTs) in the salivary glands varies according to the salivary gland from which they originate. While most of those detected in the parotid gland tend to be benign, the incidence of malignancy increases in other glands. The use of magnetic resonance imaging (MRI) in the diagnosis of SGTs is increasing every day. While conventional sequences provide sufficient data on the presence, localization, extent and number of the tumor, they are insufficient for tumor specification. With the widespread use of advanced techniques such as diffusion-weighted imaging, semi-quantitative and quantitative perfusion MRI, studies and data have been published on the differentiation of malignant or BTs and the specificity of their subtypes. With diffusion MRI, differentiation can be made by utilizing the cellularity and microstructural properties of tumors. For example, SGTs such as high cellular Warthin's tumor (WT) or lymphoma on diffusion MRI have been reported to have significantly lower apparent diffusion values than other tumors. Contrast agent uptake and wash-out levels of tumors can be detected with semi-quantitative perfusion MRI. For example, it is reported that almost all of the pleomorphic adenomas show an increasing enhancement time intensity curve and do not wash-out. On quantitative perfusion MRI studies using perfusion parameters such as Ktrans, Kep, and Ve, it is reported that WTs can show higher Kep and lower Ve values than other tumors. In this study, the contribution of advanced MRI to the diagnosis and differential diagnosis of SGTs will be reviewed.

Magnetic resonance imaging findings of intracranial hypotension.

PURPOSE: This study aims to evaluate the differences in the sizes and configurations of various structures on brain MRIs of patients with intracranial hypotension (ICH) compared to normal individuals. METHODS: The present study consisted of two study groups as 21 patients with intracranial hypotension and 21 healthy individuals. Cranial MRI findings of patients with intracranial hypotension were compared retrospectively with MRI findings of patients without any pathology. Pachymeningeal enhancement, mamillopontine distance, venous sinus diameters, transverse and straight sinus distension, pituitary gland enlargement, tonsillar herniation, bleeding (subdural, epidural), pontomesencephalic angle, lateral ventricular angle, and pituitary infundibular angle were evaluated on MRI. RESULTS: Intracranial hypotension developed spontaneously in 6 cases and secondary in 15 patients. Diffuse pachymeningeal enhancement was observed in all intracranial hypotension cases. In addition, transverse sinus distension was observed in 19 cases, straight sinus distension in 17 cases, subdural effusion in 7 cases, spinal epidural effusion in 3 cases, tonsillar herniation in 2 cases, and thrombosis in dural sinuses in 2 cases. The intracranial hypotension group vs control group had dominant transverse sinus diameter 10 ± 1.75 vs 7.52 ± 1.2 mm, straight sinus diameter 4.76 ± 0.92 vs 3.69 ± 0.57 mm, superior sagittal sinus diameter 8.35 ± 1.57 vs 6.37 ± 0.71 mm, pontomesencephalic angle 46.67 ± 9.73° vs 56.27° ± 8.9°, mamillopontine distance 5.83 ± 1.5 vs 6.85 ± 1.1 mm, lateral ventricular angle 131.13° ± 6.17° vs 135.19° ± 5.28°, pituitary infundibular angle 44.42° ± 12.09° vs 63.3° ± 11.56°, and pituitary gland height 8.5 ± 1.83 vs 5.5 ± 1.27 mm, respectively. CONCLUSION: In cases with clinically suspected intracranial hypotension, MRI findings may contribute to the diagnosis of intracranial hypotension with quantitative evaluations.

Evaluation of the Association between Paranasal Sinus Osteomas and Anatomic Variations Using Computed Tomography.

OBJECTIVE: The pathogenesis of paranasal sinus osteoma (PSO) has not been fully elucidated. It is thought that both embryological and developmental factors play a role in the etiology. The aim of the present study was to investigate the association of frequency and localization of PSOs detected on computed tomography (CT) examination with osteoma presence. METHODS: In this retrospective study conducted in December 2017 through March 2020 in Gaziosmanpasa University Faculty of Medicine, images of a total of 18,867 patients who underwent paranasal sinus, maxillofacial CT and brain CT angiography were reviewed for the presence of PSOs. Sizes of PSOs and accompanying mucosal pathologies were identified. Associations between PSOs and paranasal sinus variations were evaluated statistically compared to the control group (200 patients without PSO). RESULTS: A total of 176 patients (0.92%) were found to have PSO. Average age of the patients with PSO was 59.9 years (range: 18-93). PSOs were unilateral in 152 patients while 24 patients had multiple osteomas. Female/male ratio was 1.1/1. PSOs were most commonly located in the frontal sinuses. Frequencies of vertical concha bullosa, secondary middle turbinate, twisted uncinate, supraorbital ethmoid cell, intersinus septal cell, ethmoidomaxillary cell, Haller's cell, frontal sinus hypoplasia and sphenoid sinus hypoplasia were significantly higher in the patient group compared to the control group. CONCLUSION: Higher or lower incidence rates of some anatomic variations in the patients with PSO could be explained by the possible effects of genetic and/or environmental factor. Additional studies are needed to evaluate these possible associations.

Magnetic resonance imaging findings of redundant nerve roots of the cauda equina.

BACKGROUND: Redundant nerve roots (RNRs) of the cauda equina are often a natural evolutionary part of lumbar spinal canal stenosis secondary to degenerative processes characterized by elongated, enlarged, and tortuous nerve roots in the superior and/or inferior of the stenotic segment. Although magnetic resonance imaging (MRI) findings have been defined more frequently in recent years, this condition has been relatively under-recognized in radiological practice. In this study, lumbar MRI findings of RNRs of the cauda equina were evaluated in spinal stenosis patients. AIM: To evaluate RNRs of the cauda equina in spinal stenosis patients. METHODS: One-hundred and thirty-one patients who underwent lumbar MRI and were found to have spinal stenosis between March 2010 and February 2019 were included in the study. On axial T2-weighted images (T2WI), the cross-sectional area (CSA) of the dural sac was measured at L2-3, L3-4, L4-5, and L5-S1 levels in the axial plane. CSA levels below 100 mm2 were considered stenosis. Elongation, expansion, and tortuosity in cauda equina fibers in the superior and/or inferior of the stenotic segment were evaluated as RNRs. The patients were divided into two groups: Those with RNRs and those without RNRs. The CSA cut-off value resulting in RNRs of cauda equina was calculated. Relative length (RL) of RNRs was calculated by dividing the length of RNRs at mid-sagittal T2WI by the height of the vertebral body superior to the stenosis level. The associations of CSA leading to RNRs with RL, disc herniation type, and spondylolisthesis were evaluated. RESULTS: Fifty-five patients (42%) with spinal stenosis had RNRs of the cauda equina. The average CSA was 40.99 ± 12.76 mm2 in patients with RNRs of the cauda equina and 66.83 ± 19.32 mm2 in patients without RNRs. A significant difference was found between the two groups for CSA values (P < 0.001). Using a cut-off value of 55.22 mm2 for RNRs of the cauda equina, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) values of 96.4%, 96.1%, 89.4%, and 98.7% were obtained, respectively. RL was 3.39 ± 1.31 (range: 0.93-6.01). When the extension of RNRs into the superior and/or inferior of the spinal canal stenosis level was evaluated, it was superior in 54.5%, both superior and inferior in 32.8%, and inferior in 12.7%. At stenosis levels leading to RNRs of the cauda equina, 29 disc herniations with soft margins and 26 with sharp margins were detected. Disc herniation type and spondylolisthesis had no significant relationship with RL or CSA of the dural sac with stenotic levels (P > 0.05). As the CSA of the dural sac decreased, the incidence of RNRs observed at the superior of the stenosis level increased (P < 0.001). CONCLUSION: RNRs of the cauda equina are frequently observed in patients with spinal stenosis. When the CSA of the dural sac is < 55 mm2, lumbar MRIs should be carefully examined for this condition.

Evaluation of ischemic lesions after carotid artery stenting with diffusion-weighted imaging.

BACKGROUND: Almost 90% of cerebral thromboembolism cases are caused by atherosclerosis. Craniocervical atherosclerosis is often observed at the carotid bifurcation and is responsible for 20%-30% of all stroke cases. The course of atherosclerotic carotid artery stenosis varies depending on the grade of stenosis and characteristics of the plaque. Carotid artery stenting (CAS) can be used as a less invasive method in patients with symptomatic and asymptomatic high-grade carotid artery stenosis. Diffusion-weighted imaging (DWI) is an effective method for detection of silent or symptomatic acute ischemic lesions that may arise due to CAS or carotid endarterectomy. The number and volume of new ischemic lesions are determined using DWI. AIM: To evaluate the number and volume of ischemic lesions and their cerebral parenchymal and vascular distribution after CAS using DWI. METHODS: Forty-seven male (73.4%) and seventeen female (26.6%) patients (total, n = 64) aged 42-84 years (mean 67.96 ± 8.03 years) diagnosed with carotid stenosis between October 2006 and July 2012 were included in this retrospective study. Twelve of the cases (18.8%) were asymptomatic, while fifty-two (81.2%) were symptomatic. The area where the stenosis was highest was measured, and the stenosis rate was determined using the North American Symptomatic Carotid Endarterectomy Trial method. DWI of the cases was evaluated by two radiologists experienced in neuroradiology (B.A. with more than 15 years of experience, E.G. with more than 10 years of experience). Routine DWI examinations were carried out by a 1.5 T MR device 1 h before and after the operation. Since the ischemic lesions that developed in the first hour and in the follow-up period of 5-24 h were assumed to be due to CAS, all lesions within the first 24 h were considered as new ischemias. RESULTS: In the present study, 39 new ischemic lesions were detected in 20 cases. The average number of new lesions after all CAS operations was 0.62. They were mostly located in the occipital lobes, followed by the frontal and parietal lobes. These new ischemic lesions were most common in the middle cerebral artery territory, followed by the posterior cerebral artery territory and middle cerebral artery-posterior cerebral artery watershed areas. New lesions were found in 31.2% (20/64) of patients, including 17 (26.5%) in ipsilateral and three (4.6%) in contralateral hemispheres. New bilateral lesions were detected in one case (1.5%). The average volume of the new ischemic lesions detected by the two observers was 1.10 cm³. The numbers of newly appearing ischemic lesions in DWI after CAS were significantly higher in cases where stenting was applied on the left side of the carotid artery and in cases where longer plaques (> 1 cm) were responsible for the narrowing in symptomatic patients. The stenosis rate was low in the group with ulcerated plaques. CONCLUSION: New ischemic lesions due to CAS appear mostly in the main arterial territory but they may also occur in watershed areas.

Radiological classification of azygos anterior cerebral artery and evaluation of the accompanying vascular anomalies.

PURPOSE: There is not a classification of azygos anterior cerebral artery (ACA) based on anatomical branching levels in the literature. In the present study, a classification of azygos ACA was made based on radiological imaging for a common terminology, and frequency, accompanying vascular anomalies and malformations were investigated. METHODS: A total of 4913 cases who had brain CTA, MRA, contrast-enhanced MRI and DSA in January 2010-January 2020 period were screened for the study. Based on anatomical branching level, azygos ACAs were classified into four groups. Aneurysms, anomalies and malformations accompanying azygos ACA were identified. The associations of azygos ACA types with the presence of aneurysm or ACA A1 segment anomalies were investigated. RESULTS: Azygos ACA was observed in 57 cases (29 male and 28 female) and frequency of azygos ACA was 1.16%. Average age of the cases with ACA was 56.19 ± 19.65 years. Forty-eight of the cases had type C azygos ACA, four cases type B, four cases type D and one case type A azygos ACA. A total of nine intracranial aneurysms were identified in seven of the cases (12.28%). Five of the aneurysms were located in MCA and four in distal ACA. Most common vascular anomalies accompanying azygos ACA were unilateral vertebral artery hypoplasia and ACA A1 segment hypoplasia. Azygos types did not have significant correlations with the presence of aneurysms or ACA A1 segmental anomalies (p = 0.683 and p = 0.949, respectively). CONCLUSION: Azygos ACA is a rare variation, but it could be accompanied by aneurysms or other vascular anomalies.

Radiological Imaging Findings of Craniofacial Fibrous Dysplasia.

AIM: To present the radiological findings of fibrous dysplasia (FD) patients who had computed tomography (CT) and/or magnetic resonance imaging (MRI) scans. MATERIAL AND METHODS: This study included a total of 25 patients (17 female and 8 male) who were found to have FD based on CT examinations between March 2010 and July 2018. Involved bones, type of involvement (single or multiple) and CT appearance features (ground-glass, sclerotic, cystic or mixed type) were evaluated. RESULTS: Age range of the patients with FD was 14-55 (mean: 29.92 ± 12.63) years. Sixteen patients had single bone and nine patients had multiple bones affected. Single bone most frequently involved maxillary bones. Multiple bone involvement affected up to four bones, sphenoid bone being the most frequent. Fifteen lesions were mixed type, eight were ground-glass and two were sclerotic on CT. Intense contrast-enhancement was observed in four patients on MRI. CONCLUSION: Craniofacial FD is more frequent in young adults and women, and more commonly involves single bone, mostly maxillary and sphenoid bones. Craniofacial FDs could be of different types on radiological examinations depending upon their compositions.

Cranial Intraosseous Meningiomas: CT and MRI Findings.

AIM: To evaluate computed tomography (CT) and magnetic resonance imaging (MRI) findings of cranial intraosseous meningiomas (IOMs). MATERIAL AND METHODS: This study included ten patients (six females and four males) with IOMs who underwent cranial CT and/ or MRI examinations during May 2009?June 2018. Lesions were classified based on the following locations: the sphenoid ridge, the calvarial convexity, other skull base bones, and the sphenoid ridge + calvarial extension. Bony extension, contour irregularity or radial bone spiculation, bony changes (hyperostotic, lytic, or mixed patterns), dural calcification, cerebral edema, and the presence of soft tissue were evaluated. RESULTS: A total of eleven IOMs were identified in ten patients. The age of patients was 46?80 (mean: 55.30 ± 9.84) years. Five of the lesions were located in the sphenoid ridge + calvarium, three in the sphenoid ridge, two in the skull base, and one in the calvarial convexity. Seven lesions exhibited radial bone spiculation. Moreover, nine lesions exhibited hyperostotic CT pattern; while, two exhibited a mixed pattern. Three IOMs were accompanied with dural calcification, and peritumoral edema was observed in six IOMs. CONCLUSION: IOMs are predominantly low-grade tumors, commonly located in the periorbital area and often accompanied by soft tissue components and dural infiltrations. They most commonly lead to radial bone spiculation and bone expansion. Patients primarily have single lesions but may occasionally have multiple ones.

The evaluation of prostate lesions with IVIM DWI and MR perfusion parameters at 3T MRI.

PURPOSE: The purpose of our study was to analyze the difference between IVIM DWI and perfusion parameters of malignant lesions and benign lesions-normal prostate tissue. METHODS: This prospective study included 31 patients who had multiparametric prostate MRI with IVIM DWI due to elevated prostate-specific antigen level and clinical suspicion between February 2015 and September 2016. RESULTS: For peripheral zone, the mean values of Ktrans, Kep, iAUC, χ2 and f were significantly higher in malignant lesions, and the mean values of Dt were significantly lower in malignant lesions (p 0.00, p 0.02, p 0.00, p 0.02 and p 0.00, respectively). For transitional zone, the mean values of Ktrans, Ve, iAUC, χ2 and f were significantly higher in malignant lesions, and the mean values of Dp and Dt were significantly lower in malignant lesions (p 0.00, p 0.00, p 0.00, p 0.00, p 0.00, p 0.02 and p 0.00, respectively). For whole prostate gland, the mean values of Ktrans, Kep, Ve, iAUC, χ2 and f were significantly higher in malignant lesions, and the mean values of Dp and Dt were significantly lower in malignant lesions (p 0.00, p 0.03, p 0.00, p 0.00, p 0.00, p 0.01, p 0.04 and p 0.00, respectively). CONCLUSIONS: Restricted diffusion-pseudodiffusion and increased perfusion parameters are important to differentiate prostate cancer from benign pathologies. It is also important to keep in mind that transitional zone and peripheral zone tumors may have different perfusion and diffusion parameters. Future studies are needed to confirm our findings.

Evaluation of pineal cysts with magnetic resonance imaging.

AIM: To evaluate radiological imaging findings of patients who had been found to have pineal cyst (PC) in brain magnetic resonance imaging (MRI). METHODS: A total of 9546 patients who had brain MRI examination in March 2010-January 2018 period were studied. Fifty-six patients (44 female and 12 male) found to have PC were evaluated. Eighteen of the patients had had follow-up examinations of 2-94 mo (mean 30.50 ± 28.83). PC dimensions and volume, radiological imaging features (signal intensities, contours, internal septation-loculation and contrast-enhancement features) and natural history in cases who had been followed-up were evaluated by two radiologists. RESULTS: Of 9546 patients, 5555 were female (58.2%) and 3991 male (41.8%). Age range was 1-99 (mean 43.18 ± 20.94). PC frequency was calculated to be 0.58%. Forty-four of the 56 patients (78.57%) with PC were female and 12 male (21.43%), and their age range was 5-61 (mean 31.26 ± 12.73). Thirty-five of the PCs were typical (62.50%) and 21 (37.50%) were atypical. No significant difference was found between initial and final imaging sizes of PCs which were monitored by follow-up examinations (P > 0.05). CONCLUSION: PCs are cysts which do not show clear size and natural changes and are more frequently observed in females and in adult ages. Most of them are isointense with cerebrospinal fluid on T1 and T2A weighted images, hyperintense compared to cerebrospinal fluid on fluid-attenuated inversion recovery; sequence and smoothly contoured. Their typical forms have peripheral rim and multilocular ones may have septal contrast-enhancement.

Evaluating Ossifications of the Nuchal Ligament with Cervical Computed Tomography.

OBJECTIVE: The nuchal ligament (NL) extends from the external occipital protuberance and median nuchal line to the spinous process of the 7th cervical vertebrae. In this study, we evaluated the incidence, location level, and size of ossifications of the NL (ONL) in patients who underwent cervical computed tomography (CT) for various reasons. MATERIALS AND METHODS: The present study included 481 patients (187 females and 294 males) who underwent cervical CT from February 2011 to November 2016 due to reasons such as trauma, cervical spondylosis, neck pain, and screening for metastasis. CT was performed using 2- or 8-slice scanners. Archive images of patients on picture archiving and communication system were retrospectively evaluated by two radiologists. The structures in bone density and form detected in NL were evaluated as nuchal ossification. ONL location levels, numbers, and dimensions were determined. The relationship between both sexes and age and the incidence of ONL was investigated. RESULTS: ONL was detected in 44 patients (9.14%). The mean ages of patients with ONL and without ONL were 62.27±13.92 (23-86) and 41.78±20.76 (4-101) years, respectively. There was a statistically significant relationship between ONL and age (p<0.001). Thirty-six patients had one ONL, seven patients had two, and one patient had three. The most common ONL location was the C5 spinous process level (n=12) followed by the C6 spinous process level (n=8). The longest ONL in craniocaudal direction was 20.9 mm, and the shortest one was 3.1 mm. CONCLUSION: ONL is a smooth-contoured ovoid or round bone structure extending parallel to the longitudinal axis that can frequently be observed as one or multiple occurrences with different sizes on cervical CT images.

Duplex Doppler Sonographic Assessment of the Superior Mesenteric Artery in Patients With Mesenteric Panniculitis.

OBJECTIVES: We aimed to determine how the hemodynamic parameters of the superior mesenteric artery are affected in mesenteric panniculitis. METHODS: Twenty-one patients with a diagnosis of mesenteric panniculitis on computed tomography were evaluated with duplex Doppler sonography. The control group consisted 20 asymptomatic volunteers. The peak systolic velocity, end-diastolic velocity (EDV), resistive index (RI), pulsatility index (PI), blood flow volume, and body mass index were measured in the group of patients with mesenteric panniculitis, and the findings were compared with those of the control group. RESULTS: The mean blood flow volume and EDV were significantly higher in the patient group: The mean superior mesenteric artery blood flow volume ± SD was 917.86 ± 228.97 mL/min in the patient group versus 389.73 ± 92.72 mL/min in the control group (P < .001). The mean EDV was 31.56 ± 8.44 m/s in the patient group versus 19.27 ± 4.19 m/s in the control group (P < .001). The mean RI and PI were significantly lower in the patient group: The mean RI was 0.81 ± 0.04 in the patient group versus 0.85 ± 0.03 in the control group (P = .001). The mean PI was 2.69 ± 0.68 in the patient group versus 3.81 ± 1.13 in the control group (P = .001). the mean superior mesenteric artery diameter was 7.30 ± 0.67 mm in the patient group versus and 6.46 ± 0.66 mm in the control group (P < .001). The mean BMI was 27.95 ± 3.80 kg/m2 in the patient group versus 23.16 ± 3.47 kg/m2 in the control group (P < .001). CONCLUSIONS: In patients with mesenteric panniculitis, the Doppler spectrum of the superior mesenteric artery shows detectable changes, which are characterized by decreased vascular resistance and increased blood flow.

Radiological imaging findings of Dyke-Davidoff-Masson syndrome.

Radiological findings of Dyke-Davidoff-Masson syndrome (DDMS) in patients with different etiologies are presented in our study. The study included 12 patients (seven females, five males) for whom radiological examinations were requested due to reasons such as epilepsy, mental retardation, and/or hemiplegia. CT was performed in 12, MRI in 6, MRA in 1, and DSA in 1 patient. Following imaging findings were evaluated: cerebral and cerebellar involvement (laterality, encephalomalacia), affected territories, ventricular enlargement, sulcal enlargement, calvarial thickening, and paranasal sinus enlargement hyperaeration. Age range of the patients was 5-62 (mean 34.1 ± 21.7). Left hemicrania was affected in eight patients, right hemicrania in four. Ipsilateral calvarial thickening and lateral ventricular dilatation were observed in all patients. 11 patients had ipsilateral frontal sinus hyperaeration, sulcal enlargement and encephalomalacia. Wallerian degeneration of the mesencephalon and middle fossa hypoplasia was seen in ten patients, mastoid hyperaeration, third ventricular enlargement and thalamic involvement in nine, and corpus callosum, basal ganglion injury, and sphenoid sinus hyperaeration in eight. MCA, ACA, and PCA territories were involved in six patients. Only MCA territory involvement was seen in four patients. Cerebellar atrophy was contralateral in two patients. Symmetric bilateral atrophy was observed in one patient. DDMS can be encountered with different radiological findings based on cerebral damage formation process and the extent of damage. Patients may have different levels of cerebral hemiatrophy, ipsilateral carvarial thickening, and lateral ventricular dilatation.

Radiological imaging findings of scheuermann disease.

AIM: To find accompanying anomalies of typical and atypical Scheuermann's disease (SD) is reported in the present study. METHODS: Study included 20 patients (16 men and 4 women) who had radiological imaging radiography, magnetic resonance imaging (MRI) and computed tomography, if available, due to back pain, curved back and low back pain in November 2011-February 2016 period. Patients were categorized into typical and atypical patterns based on the region involved. Thoracic kyphosis values were measured using real Cobb angle. Accompanying disc degeneration, herniations and spinal cord pathologies were studied using MRI. RESULTS: Age of the patients ranged from 11.0 to 23.0 (mean 17.2 ± 3.0). Typical pattern of SD were detected in 15 patients while atypical pattern were detected in 5 patients. Cobb angle range was 40.2-67.2 (mean 55.5 ± 8.7) in typical Scheuermann's patients and 24.7-49.9 (mean 36.7 ± 10.8) in atypical ones. Intervertebral level was affected and had the measures of 3-8 (mean 5.3 ± 1.6) and 7-9 (mean 8.2 ± 0.8) in typical and atypical Scheuermann's patients, respectively. Level of degenerative disc disease in MRI was 1-7 discs (mean 4.1 ± 1.7) in typical patients and 5-10 discs (mean 7.6 ± 1.9) in atypical patients. CONCLUSION: SD can be seen in typical and atypical patterns, typical being more frequent. Because degenerative disc diseases, herniations and cord pathologies such as syringomyelia can accompany SD (albeit more common in atypical pattern), it is necessary to evaluate these patients with plain radiography and MRI together.

Computed tomography and magnetic resonance imaging findings of acquired dacryocystoceles.

In this study, radiological findings of acquired dacryocystocele are presented. A total of 13 dacryocystoceles including bilateral in two of the patients, in four patients on the left and in five patients on the right, were determined. Six of the patients had dacryocystocele infection. Average density of the non-infected dacryocystoceles was 11.8±7.8 Haunsfield units (HU), while the median density value of infected ones was 35.0 HU. There was expansion on unilateral nasolacrimal duct in four patients. Acquired dacryocystoceles are rare masses in medial canthal area, and their radiological imaging findings may vary based on etiological factors and presence of infections.