Assignment Confidence in Localization of the Hand Motor Cortex: Comparison of Structural Imaging With Functional MRI.

OBJECTIVE: The purpose of this study was to assign confidence levels to structural MRI and functional MRI (fMRI) for localization of the primary motor cortex. MATERIALS AND METHODS: Ninety-one fMRI studies with at least one motor task (178 hemispheres) were identified. Three anatomic assessments were used to localize the primary motor cortex: relation between the superior frontal sulcus and precentral sulcus; cortical thickness; and configuration of the precentral knob. In 105 hemispheres, interreader agreement was assessed for two investigators with different experience levels. Confidence ratings from 0 to 5 (0, no confidence; 5, 100% confidence) were assigned for fMRI and each anatomic localization method. RESULTS: Cortical thickness had the highest confidence rating (mean, 4.90 ± 0.47 [SD]) with only one failure. The relation between the superior frontal sulcus and precentral sulcus had the lowest confidence rating (4.33 ± 0.91) with three failures. The greatest statistical significance was observed for the cortical thickness and superior frontal sulcus-precentral sulcus methods (post hoc Bonferroni test, p < 0.001). Confidence rating scores were significantly higher for the cortical thickness sign than for fMRI results (4.72 ± 0.54) for a single motor task (post hoc Bonferroni test, p = 0.006); however, the mean confidence rating for fMRI improved to 4.87 ± 0.36 when additional motor tasks were performed. Interreader differences were least for the cortical thickness sign (paired t test, t = 4.25, p < 0.001). CONCLUSION: Cortical thickness is a better anatomic landmark than fMRI localization for assigning confidence regarding localization of the primary motor cortex; however, localization of motor function is more specific when combined with fMRI findings. Multiple techniques can be used to increase confidence in identifying the hand motor cortex.

Limbic pathway lesions in patients with multiple sclerosis.

BACKGROUND: Multiple sclerosis (MS) is a well-known demyelinating disease to cause cognitive dysfunction. The limbic system, relevant to memory, can be easily overlooked in conventional magnetic resonance imaging (MRI). PURPOSE: To investigate the distribution and frequency of demyelinating lesions affecting white matter connections of the limbic system based on localization with diffusion tensor imaging (DTI)-derived fractional anisotropy (FA) color maps compared to three-dimensional T2-weighted (T2W) and FLAIR volumes in MS patients. MATERIAL AND METHODS: One hundred and fifty patients with a known diagnosis of MS were identified for this Health Insurance Portability and Accountability (HIPAA)-compliant retrospective cross-sectional study. DTI-derived FA color maps, co-registered to T2W and FLAIR images, were analyzed for lesions affecting the three white matter tracts of the limbic system including cingulum, fornix, and mammilothalamic tracts by two investigators. The approximate location of the lesions on FLAIR was always confirmed on the co-registered DTI-derived FA color maps. RESULTS: Of the 150 patients analyzed, 14.6% had cingulum lesions, 2.6% had fornix lesions, and 2.6% had mammilothalamic tract lesions; 21.3% of patients had at least one of the three tracts affected. CONCLUSION: A relatively high frequency of lesions involving the limbic tracts may explain memory deficits and emotional dysfunction commonly experienced by patients with MS. The combined information from T2W, FLAIR, and DTI-derived FA color map allowed for more accurate localization of lesions affecting the major white matter tracts of the limbic system.

Previous chronic cerebral infarction is predictive for new cerebral ischemia after carotid endarterectomy.

BACKGROUND: The purpose of this study was to investigate the relation between preoperative chronic cerebral ischemia and postoperative new cerebral ischemia in patients undergoing carotid endarterectomy (CEA). METHODS: We reviewed the diffusion weighted magnetic resonance images (DWI) of the 51 patients (37 men, mean age 68.8 ± 8.4 years) undergoing isolated CEA in the preoperative and early postoperative period. The number, anatomic location and the size of new ischemic lesions were recorded. RESULTS: In the preoperative period, 28 (54.9 %) patients were symptomatic. There was chronic cerebral infarction in the preoperative DWI images of 17 patients (33.3 %). In the postoperative period, there was newly developed cerebral ischemia in postoperative DWI images of eight (15.7 %) patients. Six of the eight patients with newly developed cerebral ischemia had chronic cerebral infarction in their preoperative DWI images. The incidence of newly developed cerebral ischemia after CEA in patients with preoperative chronic cerebral ischemia was significantly higher than the incidence in patients without preoperative chronic cerebral ischemia (p = 0.01). CONCLUSION: The results of the present study suggest that preoperative chronic cerebral ischemia may aggravate postoperative newly developed cerebral ischemia in patients undergoing CEA.

Fahr disease: use of susceptibility-weighted imaging for diagnostic dilemma with magnetic resonance imaging.

Fahr disease (FD) is a well-defined rare neurodegenerative disease that is characterized by idiopathic bilateral symmetric extensive striopallidodentate calcifications. The patients may present with diverse manifestations, most commonly movement disorder, cognitive impairment, and ataxia. Computed tomography (CT) is considered to be critical for accurate diagnosis because it is difficult to reliably identify calcifications by routine magnetic resonance imaging (MRI). Susceptibility-weighted imaging (SWI) is a relatively new 3D gradient-echo (GE) MR sequence with special phase and magnitude processing. SWI phase images can recognize calcifications definitively with higher sensitivity compared to other MRI sequences. In this article, we present two cases of FD with different manifestations and neuroimaging in different age groups and genders, which were diagnosed by SWI and confirmed with CT, and we discuss the contribution of SWI in the diagnosis of FD. In conclusion, we suggest integrating SWI with MRI protocol to identify calcifications in suspicion of neurodegenerative disorders.

Anterior Sacral Meningocele Masquerading as an Ovarian Cyst: A Rare Clinical Presentation Associated with Marfan Syndrome.

Anterior sacral meningocele is a very rare clinical entity characterized by herniation of a meningeal sac through a sacrococcygeal defect. We report a case of a 20-year old female with Marfan syndrome who presented with abdominal distention that was misdiagnosed as an ovarian cyst on pelvic ultrasound. Pelvic magnetic resonance (MR) imaging showed large, well-defined multiloculated intrasacral and presacral cysts communicating via two separate broad necks and extending through defects in anterior aspect of sacral vertebrae. This case emphasizes that anterior sacral meningocele should be considered in the differential diagnosis of cases with pelvic cysts particularly in patients with underlying connective tissue disorders. Because severe neurologic complications or even death may occur without proper preoperative planning in such cases, MR imaging should always be performed for evaluation and characterization of pelvis cystic lesions.

Is there a role for DWI in the diagnosis of sacroiliitis based on ASAS criteria?

PURPOSE: Sacroiliitis based on MRI is one of the main diagnostic criteria of axial spondyloarthritis (SpA). Our purpose was to assess (a) whether apparent diffusion coefficient (ADC) values on diffusion-weighted imaging (DWI) differ between regions of bone marrow edema (BME) and subchondral normal-appearing bone marrow (NABM) in active sacroiliitis, (b) whether ADC values can differentiate early SpA and chronic SpA, both in the active and inactive phase, and (c) whether ADC values are related to laboratory findings. MATERIALS AND METHODS: 47 patients (24 female, 23 male, mean age: 38.53 years) with the diagnosis of SpA were included in this retrospective study. 20 age- and sex-matched subjects without SpA constituted the control group. ADC measurements were taken from all lesions and NABM of each sacroiliac joint. RESULTS: A total number of 120 subchondral BME lesions (acute: 17, chronic active: 103) were noted. The mean ADC values of the BME lesions (1.30 ± 0.18 × 10(-3) mm(2)/s) were significantly higher than the ADC values in the NABM regions (0.55 ± 0.08 × 10(-3) mm(2)/s) as well as in both the control group (0.56 ± 0.05 × 10(-3) mm(2)/s) and the chronic inactive group (0.54 ± 0.03 × 10(-3) mm(2)/s). There were more BME regions in patients with chronic active sacroiliitis than early SpA patients. Correlation was found between the CRP values and ADC values. CONCLUSION: DWI with ADC values may be complementary to FS T2-weighted or STIR MR images for accurately diagnosing inflammatory sacroiliitis. The value of DWI versus dynamic contrast-enhanced imaging in the follow-up needs to be clarified.

Atypical developmental venous anomaly associated with contrast enhancement and hyperperfusion in the surrounding basal ganglia.

Developmental venous anomalies (DVAs) are the most common type of cerebral vascular malformations. They are generally accepted as variants of venous development and frequently identified incidentally, particularly on contrast-enhanced MR imaging. Most of the DVAs do not affect the integrity of the surrounding parenchyma. This article discusses an atypical DVA which is associated with contrast enhancement and increased perfusion within the drainage territory of the DVA, probably due to anomalous venous drainage. These unusual perfusion patterns of the DVAs should be differentiated from other entities such as hypervascular brain tumors or ischemia with hemodynamical changes which have different clinical management.

A rare cause of odynophagia: infected tracheal diverticulum.

Tracheal diverticulum is a relatively rare lesion. Tracheal diverticula are divided into two subgroups as congenital and acquired with different characteristics and etiologies. The majority of these anomalies is asymptomatic and found as incidental findings on radiological imaging. This article presents a case of an infected tracheal diverticulum presenting with odynophagia. It should be noted that infection may obstruct the air-filled lumen of the diverticulum, causing a diagnostic challenge. Multislice computed tomography with coronal reconstructed images is the modality of choice for diagnosing diverticulum and assessing therapeutic response in associated complications.

Brain diffusion changes in unilateral carotid artery stenosis with non-shunt endarterectomy: Correlation with white matter lesions.

OBJECTIVE: Carotid stenosis is associated with hemodynamic cerebral ischemia. Diffusion-weighted MR imaging allows for the assessment of changes related to alterations in tissue integrity. The aim of this study was to investigate (a) whether white matter lesions (WML) and apparent diffusion coefficient (ADC) values differ between ipsilateral and contralateral hemispheres, (b) whether ADC values are related to WMLs and common vascular risk factors, and (c) whether ADC values differ after carotid endarterectomy (CEA) without a shunt in patients with unilateral internal carotid artery stenosis (ICAS). METHODS: Twenty-five patients (16 men, 9 women; mean age of 68 years) with unilateral ICAS (≥ 70% carotid stenosis) were assessed with brain MRI before and after CEA, prospectively. Two experienced radiologists scored the WMLs. Bilateral ADC values in anterior and posterior periventricular WM, occipital WM, and thalamus were evaluated on preoperative and postoperative MRI. Differences in ADC values and WML scores between the two hemispheres were assessed and associations between ADC values, WML scores, and explanatory variables (e.g., age, sex, vascular risk factors) were analyzed. RESULTS: WMLs were significantly greater and ADC values were elevated in the ipsilateral cerebral WM. After CEA, ADC values rapidly decreased but remained higher than within the contralateral hemisphere. Ipsilateral hemispheric ADC values were associated with basal ganglia WMLs. No association between ADC values and vascular risk factors was found. CONCLUSION: ICAS is associated with increased diffusion in normal-appearing WM in comparison to more prominent chronic ischemic lesions. CEA has a partial effect on diffusion. These cerebral changes may be related to chronic low-grade ischemic damage that is induced by ICAS.

Dilatation of the Virchow-Robin spaces as an indicator of unilateral carotid artery stenosis: correlation with white matter lesions.

BACKGROUND: Virchow-Robin space (VRS) dilatation is related to many pathologic conditions, mostly associated with vascular abnormalities. White matter lesions (WMLs) are commonly seen on brain magnetic resonance imaging (MRI) with advancing age and generally considered as potential markers for vascular disease. PURPOSE: To investigate if asymmetric dilatation of VRSs and WMLs are associated with unilateral internal carotid artery stenosis (ICAS) and to test the relationship between dilated VRSs and common vascular risk factors. MATERIAL AND METHODS: Twenty-nine patients (18 men, 11 women; mean age, 68.62 years) with unilateral ICAS (≥70% carotid stenosis) undergoing carotid endarterectomy were identified for this Health Insurance Portability and Accountability Act (HIPAA) compliant prospective study and assessed with brain MRI. Two experienced radiologists scored VRSs and WMLs and evaluated old infarcts, chronic lacunar infarcts, and cerebral atrophy. Asymmetry of WML and VRS scores between two cerebral hemispheres was assessed and associations between VRS scores, WML scores, and explanatory variables (e.g. age, sex, vascular risk factors, and atrophy) were tested. RESULTS: In this study, WMLs and basal ganglia VRSs were significantly greater in the unilateral hemisphere with ICA stenosis than contralateral hemisphere. Basal ganglia VRSs were associated with WMLs and internal cerebral atrophy. No association between the severity of VRSs and vascular risk factors was found. CONCLUSION: ICA stenosis may contribute as a factor in the development of WMLs and dilatation of VRSs by causing chronic hypoperfusion. VRS dilatation may be an additional MRI marker of ICAS.

Evaluation of Arterial Stiffness in Patients with Behçet's Disease by Using Noninvasive Radiological Methods such as Intima-Media Thickness of the Carotid, Ankle-Brachial Pressure Index, Coronary Artery Calcium Scoring, and Their Relation to Serum Fetuin-A Levels: A Case-Control Study.

BACKGROUND: Behçet's disease (BD) is a chronic, recurrent inflammatory systemic vasculitis. Evidence for increased atherosclerosis in BD has been observed. The relation between cardiovascular risk factors and increased atherosclerosis in patients with BD is still controversial. OBJECTIVE: We performed this study to evaluate arterial stiffness in patients with BD by using noninvasive radiological methods such as carotid artery intima-media thickness (CIMT), ankle-brachial pressure index (ABPI), coronary artery calcium score (CACaS), and their relation to serum fetuin-A levels, which was recently found to be important in vascular calcification. METHODS: This prospective study included 26 patients with BD and 25 control subjects. In all patients, the CIMT, ABPI, CACaS, and serum fetuin-A levels were examined. RESULTS: The CIMT and CACaS were statistically higher and the ABPI was statistically lower in BD patients than in the control group. All p-values were <0.001. Positive correlations were found between the CACaS and CIMT, and negative correlations were found between the CACaS and ABPI. Although the values of fetuin-A were higher in BD, the difference was not statistically significant (p=0.064). However, the correlations found between fetuin-A levels and CIMT and between fetuin-A levels and CACaS were significant. CONCLUSION: The CIMT, CACaS, and ABPI are all useful in detecting structural and functional vascular damage in BD.

Distal tibial osteochondroma causing fibular deformity and deep peroneal nerve entrapment neuropathy: a case report.

Osteochondromas are the most common benign bone tumors, comprising 9% of all bone tumors and 35% of benign bone tumors. They are frequently diagnosed incidentally. Osteochondromas are mostly asymptomatic, but may cause mechanical findings depending on the location and size of the tumor. Rarely, they may originate from the interosseous surface of the tibia and affect the fibula. We report here a case of a rare osteochondroma originating from the distal tibial metaphysis and causing deep peroneal nerve entrapment syndrome with clinical and radiological findings. To our knowledge, this is the first case in the literature.

Cerebral venous thrombosis as a rare cause of subarachnoid hemorrhage: case report and literature review.

We report a 48-year-old woman presenting with subarachnoid hemorrhage (SAH) as the first manifestation of superior sagittal sinus thrombosis. In a literature review of 73 cases, SAH associated with cerebral venous thrombosis (CVT) was usually seen at the cerebral convexities. SAH was adjacent to thrombosed venous structures; therefore, the most possible explanation seems to be the rupture of cortical veins due to extension of thrombosis. Computed tomography (CT) was effective for diagnosis of CVT in only 32% of the cases. CVT should be considered when SAH is limited to cerebral convexities and magnetic resonance (MR) imaging with MR venography should be performed.

Advanced MR imaging techniques in the evaluation of nonenhancing gliomas: perfusion-weighted imaging compared with proton magnetic resonance spectroscopy and tumor grade.

A significant number of nonenhancing (NE) gliomas are reported to be malignant. The purpose of this study was to compare the value of advanced MR imaging techniques, including T2*-dynamic susceptibility contrast PWI (DSC-PWI) and proton magnetic resonance spectroscopy ((1)HMRS) in the evaluation of NE gliomas. Twenty patients with NE gliomas underwent MRI including DSC-PWI and (1)HMRS. The relative CBV (rCBV) measurements were obtained from regions of maximum perfusion. The peak ratios of choline/creatine (Cho/Cr) and myo-inositol/creatine (mIns/Cr) were measured at a TE of 30 ms. Demographic features, tumor volumes, and PWI- and (1)HMRS-derived measures were compared between low-grade gliomas (LGGs) and high-grade gliomas (HGGs). In addition, the association of initial rCBV ratio with tumor progression was evaluated in LGGs. No significant difference was noted in age, sex or tumor size between LGGs and HGGs. Cho/Cr ratios were significantly higher in HGGs (1.7±0.63) than in LGGs (1.2±0.38). The receiver operating characteristic analysis demonstrated that a Cho/Cr ratio with a cutoff value of 1.3 could differentiate between LGG and HGG with a specificity of 100% and a sensitivity of 71.4%. There was no significant difference in the rCBV ratio and the mIns/Cr ratio between LGG and HGG. However, higher rCBV ratios were observed with more rapid progressions in LGGs. The results imply that Cho/Cr ratios are useful in distinguishing NE LGG from HGG and can be helpful in preoperative grading and biopsy guidance. On the other hand, rCBV ratios do not help in the distinction.

Localized cystic disease of the kidney: a rare cause of hypertension in a young adult.

Localized cystic disease of kidney (LCDK) is a rare, non-familial, non-progressive renal disorder that is not associated with cysts or disorders in other organs. Only a few cases have been reported in the literature. While this condition is morphologically identical to the autosomal dominant form of polycystic kidney disease, it is not inherited and is not associated with significant deterioration of renal function. We present a case of a 16-year-old male patient who suffered from hypertension for over two years. On imaging we found several, variable-sized cysts in the upper half of the right kidney. The left kidney and lower segment of the right kidney were normal. Selective renal vein catheterization and sampling showed markedly elevated renin level in the right upper segmental vein (92 pg/ml, normal value: 11-33 pg/ml). The patient underwent a right upper heminephrectomy and histopathology was suggestive of LCDK. After surgery, the patient's blood pressure returned to normal levels without any need of antihypertensive medication and he is under follow-up on outpatient basis for the past two years.

Metastasis to the male breast from squamous cell lung carcinoma.

Metastasis to breast from extra mammarian organs is quite rare with an incidence of 0.5-3%. Malignancies that most commonly metastasize to breast are lymphomas, leukemias, and malignant melanoma. Metastasis of lung cancer to breast is a very rare condition. We present here a case with squamous cell lung cancer that metastasized to breast. A 65-year-old man presented with cough in addition to a mass in the left breast, which had been noted 3 weeks ago and grown gradually since then. A histopathological diagnosis of metastasis of squamous lung cancer was made for the mass in the left breast. PET/CT scan showed no distant metastasis. Chemoradiation therapy was applied for lung cancer. As the prognosis of such patients is extremely poor, it is of a great importance to distinguish a primary breast cancer from a metastatic breast lesion in order to determine the appropriate treatment modality.

The role of diffusion-weighted examination in non-polyploid gallbladder malignancies: A preliminary study.

BACKGROUND/AIMS: The aim of the present study was to investigate the diagnostic value of diffusion-weighted magnetic resonance imaging in gallbladder malignancies, which are typically diagnosed during surgery because the radiologic findings are similar to those of cholecystitis-caused diffuse thickening of the gallbladder wall. MATERIALS AND METHODS: Seven patients with gallbladder malignancies and nine patients with benign gallbladder pathology were included in this study. In one of the patients with a malignancy, a lesion was determined on the porcelain gallbladder; in another patient, acute myeloblastic leukemia had infiltrated the gallbladder, causing the diffuse wall thickening. Five subjects had a primary malignant gallbladder. The view of the bladder wall was evaluated visually in increasing b values. Apparent diffusion coefficient measurements were obtained from at least three sites of the bladder wall in each patient, and the results of the measurements were analyzed after comparing the malignant and benign groups. In the malignant group, the results of the radiological outcomes were compared with histological examinations. In the benign group, cholecystitis was diagnosed by observing normalization of the bladder wall thickening via surgery or medical treatment. RESULTS: There was a statistically significant difference in apparent diffusion coefficient levels between the malignant group, which caused diffuse thickening of the gallbladder wall, and the benign group (Student t test, p<0.01). CONCLUSIONS: According to this preliminary study, observation of distinct brightness of the gallbladder wall in diffusion-weighted examination with a high b value is a significant finding in terms of diffuse gallbladder malignancy. A value below the 0.86 mm 2 /sn cut-off was significant for malignancy in apparent diffusion coefficient mapping.

The value of diffusion-weighted magnetic resonance imaging in the differential diagnosis in diffuse bowel wall thickening.

BACKGROUND/AIMS: We aimed to investigate the value of diffusion-weighted magnetic resonance imaging in the differentiation of benign-malignant diffuse bowel wall thickening (scirrhous colon carcinoma) and to discuss the diagnostic importance and potential use of apparent diffusion coefficient measurements. MATERIALS AND METHODS: A total of 41 patients (32 males, 9 females; mean age, 57 years) with diffuse bowel wall thickening diagnosed on computed tomography were included in this study. The magnetic resonance imaging was performed on a 1.5 T scanner (Siemens-Espree). Changes in the signal intensity of the lesions were determined by their appearance in images at b800 s/mm 2 , and apparent diffusion coefficient values were also calculated. Lesions were classified in two groups according to the presence of hyperintensity on b800 images and results of endoscopic biopsies. The differences in mean apparent diffusion coefficient values between the two groups were compared with the Mann-Whitney U test, and threshold values were determined with receiver operating characteristic curve analysis. RESULTS: The difference between the mean apparent diffusion coefficient values of benign and malignant groups was statistically significant, and the apparent diffusion coefficient values of benign lesions were significantly higher than of malignant lesions (p<0.05). By using a cut-off value of 1.21 x 10-3mm2 /s, apparent diffusion coefficient had a sensitivity of 100%, specificity of 87.3%, and accuracy of 89.3% in the discrimination of malignant colorectal pathologies. With the visual assessment of the diffusion weighted images and the measurement of apparent diffusion coefficient values, malignant and benign lesions could be differentiated, with 100% sensitivity, 89.2% specificity, and 90.4% accuracy. Although some benign lesions were interpreted as malignant,no malignant lesion was determined as benign in the visual assessment. CONCLUSIONS: Diffusion-weighted magnetic resonance imaging and apparent diffusion coefficient values together can successfully differentiate malignant from benign diffuse bowel wall thickening.

Diagnostic value of susceptibility-weighted imaging of abdominal wall endometriomas during the cyclic menstrual changes: a preliminary study.

OBJECTIVE: The purpose of this study is to investigate the value of susceptibility-weighted imaging (SWI) for the evaluation of cyclic morphological and hemorrhagic changes in abdominal wall endometriomas (AWE). MATERIALS AND METHODS: Fourteen patients with a total of 17 lesions who were admitted with complaints of abdominal wall mass and cyclic pain were evaluated by MRI. Patients were scanned during the first three days of the menstrual cycle and during the mid-cycle phase (day 13-15). In addition to conventional images SWI was performed. The signal changes within the lesions on SWI were compared and graded on both studies. RESULTS: There was no significant difference in the size of the lesions in the early days of the menstruation compared to the mid-menstrual period. The SWI taken on mid-cycle phase showed that the center was hyperintense and the peripheral zone was hypointense in all lesions. A signal void related to increased blood and the shrinkage of complete disappearance of hyperintensity in the venter of the lesion was seen 15 (88%) of the 17 cases on the SWI series performed during the menstrual phase scan. CONCLUSION: SWI is a sensitive technique and has the capability to show hemorrhage and deposition of hemosiderin within the lesions. For patients suspected with AWE, valuable diagnostic findings may be obtained if the MRI examination including SWI is performed during the early and mid phase menstrual cycle.