Gokhan Ocakoglu

Ischiofemoral impingement: evaluation with new MRI parameters and assessment of their reliability

ObjectiveThe aim of this study was to describe the magnetic resonance imaging (MRI) findings in patients with ischiofemoral impingement (IFI) and to evaluate the reliability of these MRI findings.Materials and methodsSeventy hips of 50 patients with hip pain and quadratus femoris muscle (QFM) edema and 38 hips of 30 control cases were included in the study. The QFM edema and fatty replacement were assessed visually. Ischiofemoral space (IFS), quadratus femoris space (QFS), inclination angle (IA), hamstring tendon area (HTA), and total quadratus femoris muscle volume (TQFMV) measurements were performed independently by two musculoskeletal radiologists. The intra- and interobserver reliabilities were obtained for quantitative variables.ResultsIFS, QFS, and TQFMV values of the patient group were significantly lower than those of controls (P < 0.001). HTA and IA measurements of the patient group were also significantly higher than in controls (P < 0.05). The QFM fatty replacement grades were significantly higher in the patient group than in the control group (P < 0.001). Inter- and intra-observer reliabilities were strong for all continuous variables.ConclusionClinicians and radiologists should be aware of IFI in patients with hip or groin pain, and MRI should be obtained for the presence of the QFM edema/fatty replacement, narrowing of the IFS-QFS, and other features that may help in the clinical diagnosis of IFI for the proper diagnosis and treatment of the disease.

Role of Duplex Power Doppler Ultrasound in Differentiation between Malignant and Benign Thyroid Nodules

Objective To evaluate the usage of duplex power Doppler ultrasound (PDUS) for the differentiation of benign and malignant thyroid nodules. Materials and Methods We prospectively examined 77 thyroid nodules in 60 patients undergoing ultrasound-guided fine needle aspiration biopsy (FNAB). Each nodule was described according to size, inner structure, borders, parenchymal echogenicity, peripheral halo formation, and the presence of calcification (B-mode ultrasound findings). Vascularity as determined by PDUS imaging was defined as non-vascular, peripheral, central, or of mixed type. For each nodule, the pulsatility index (PI) and resistive index (RI) values were obtained. Results of FNAB and surgical pathological examination (if available) were used as a proof of final diagnosis to categorize all nodules as benign or malignant. A receiver operating characteristic (ROC) curve analysis was performed to establish cut-off, sensitivity, and specificity values associated with RI-PI values. Results A significant relationship was observed between malignancy and irregular margins, microcalcifications, and hypoechogenicity on ultrasound examination (p < 0.05). The pattern of vascularity as determined by PDUS analysis was not a statistically significant criterion to suggest benign or malignant disease in this study (p > 0.05). The central, peripheral, and mean RI-PI values were higher in malignant nodules when compared to the other cytologies (p < 0.05). Conclusion Vascularity is not a useful parameter for distinguishing malignant from benign thyroid nodules. However, RI and PI values are useful in distinguishing malignant from benign thyroid nodules.

Statistical Shape Analysis of Differences in the Shape of the Corpus Callosum Between Genders

Sexual dimorphic characteristics, which play an important role in human evolution studies and biological research, can be studied morphologically and metrically. Geometric morphometrics allows a better assessment of morphological characteristics. Statistical shape analysis has a long history in neuroanatomical and other research. The aim of this study was to identify shape differences of the corpus callosum between genders. Landmark coordinate data were collected from two‐dimensional magnetic resonance imaging scans of 93 homogeneously aged patients, 45 men and 48 women. These data were analyzed using Euclidean distance matrix analysis and thin plate spline analysis. The general shape variability of the corpus callosum of men was greater than that of women (men, 0.134; women, 0.097). We found no significant difference between sexes in the general shape of the corpus callosum, but we did find significant differences in the distances between some landmarks. Deformation of the corpus callosum between men to women was mainly detected in the posterior of the corpus callosum. These results serve as a reference for future studies on shape alterations of the corpus callosum associated with certain conditions. Anat Rec, 2007.

Neurochemical–structural changes evaluation of brain in patients with obstructive sleep apnea syndrome

PURPOSE To evaluate neurochemical and structural changes in the patients with newly diagnosed obstructive sleep apnea syndrome (OSAS) by MR spectroscopy (MRS), T2 relaxometry, and diffusion weighted imaging (DWI). MATERIAL AND METHODS Following the acquisition of routine cranial MR, MRS, T2 relaxometry, and DWI images; spectroscopic metabolite ratios and DWI-T2 relaxometry findings of the thalami, hippocampi, frontal white matter (FWM) and frontal cortex of 24 OSAS patients and 9 controls were statistically compared. The relationship between two groups was evaluated with Mann-Whitney test. RESULTS Spectroscopic measurements in the frontal cortex and frontal white matter of the OSAS patients revealed significantly lower NAA/Cr ratios than those of the control group (P=0.004 and P=0.006, respectively). The measurements in the frontal white matter of the OSAS patients exhibited significantly lower NAA/Cho ratios compared with those of the control group (P=0.005). Thalamic Cho/Cr ratios of the patient group were significantly higher than those of the control group (P=0.002). In terms of the ADC-T2 relaxometry values, there was no significant relationship between the patient and the control groups (P>0.05). CONCLUSION MRS is a useful and non-invasive modality in showing neurochemical changes in various regions of the brain but our data does not show any change on diffusion weighting or T2 quantification in the OSAS group. DWI and T2 relaxometry appear to be not effective techniques to evaluate the brain structural changes of the patients with newly diagnosed OSAS.

Morphologic Features and Flow Void Phenomenon in Normal Pressure Hydrocephalus and Other Dementias: Are They Really Significant?

RATIONALE AND OBJECTIVE The aim of this study was to determine the distinctive features of normal-pressure hydrocephalus (NPH) and other dementias on routine T1-weighted and T2-weighted magnetic resonance (MR) images. Also, the contribution of these parameters to the diagnosis and treatment of NPH was investigated. MATERIALS AND METHODS Routine MR images were used to investigate the morphologic features (dilatation of Sylvian cisterns, narrowness of convexity sulci, thickness of corpus callosum (TCC), and dilatation of perihippocampal fissures) and the flow void phenomenon (FVP) in patients with idiopathic NPH (INPH) and other dementias. Routine MR images of 18 patients with INPH, 11 with dementias other than INPH, and 20 controls were retrospectively examined. Morphologic features and the FVP were graded subjectively. The TCC was measured quantitatively. Morphologic parameters, the FVP, and the shunt response were assessed using Kruskal-Wallis and Mann-Whitney U tests. RESULTS The mean FVP score was significantly higher in patients with INPH (2.89 +/- 0.75) than in controls and patients with other dementias (1.1 +/- 0.85 and 1.09 +/- 0.83, respectively) (P < .001). There was significant difference in terms of TCC between patients with INPH (3 +/- 0.7 mm), those with other dementias (1.9 +/- 0.7 mm), and controls (5.2 +/- 0.8 mm) (P < .001). Significant differences in terms of other morphologic features were found between patients with INPH and those with other dementias (P < .05). No significant difference was found between morphologic parameters and the FVP and the outcome of cerebrospinal fluid diversion (P > .05). CONCLUSIONS Intense FVP is a signature of but is not pathognomonic for INPH. The morphologic analysis of MR images can be distinctive for the diagnosis of INPH or dementias other than INPH. Detailed evaluation of morphologic features and the FVP in routine MR workup of dementia will be useful for accurate diagnosis.

Evaluation of spontaneous third ventriculostomy by three-dimensional sampling perfection with application-optimized contrasts using different flip-angle evolutions (3D-SPACE) sequence by 3 T MR imaging: Preliminary results with variant flip-angle mode

PURPOSE This prospective study aimed to evaluate the use of three-dimensional sampling perfection with application-optimized contrasts using different flip-angle evolutions (3D-SPACE) in the diagnosis of spontaneous third ventriculostomy (STV) and to compare it with phase-contrast cine magnetic resonance imaging (PC-MRI). METHODS PC-MRI and 3D-SPACE images were obtained in 15 patients with hydrocephalus for evaluation of STV as well as in 10 control cases. The presence of STV was evaluated visually by two experienced radiologists on both PC-MRI and 3D-SPACE images, and the results were statistically compared. RESULTS There was a strong correlation between PC-MRI and SPACE scores for both readers (correlation coefficient [r]=0.784; P=0.001). There was also a good correlation between PC-MRI scores and consensus-based results. Interobserver reliabilities were strong for all STV scores. In addition, there was excellent correlation between 3D-SPACE scores and consensus-based results (first readers kappa value: 0.87; second readers kappa value: 1). CONCLUSION 3D-SPACE can provide morphological-physiological information for the evaluation of STV with no need for additional PC-MRI analysis or other sequences. As a non-invasive test, it can also be included among the first line of choices of MRI sequences for patients with obstructive hydrocephalus.

XRCC1 Gene Polymorphisms and Risk of Lung Cancer in Turkish Patients

Abstract Polymorphisms in the X-ray repair cross complementing 1 (XRCC1) gene have been found to be associated with susceptibility to various types of cancers. We investigated the association between the XRCC1 gene Arg399Gln polymorphism and the susceptibility to lung cancer in Turkish patients. To determine the association of this polymorphism with the risk of lung cancer in Turkish patients, a hospital-based case-control study was designed, involving 67 patients with lung cancer and 60 control subjects with no cancer history who were matched for age and gender. XRCC1 genotypes (Arg/Arg, Arg/Gln, and Gln/Gln) were determined using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis on genomic DNA. No statistically significant relationship was determined between the lung cancer and control groups (p>0.05). Among the patients, 61% were Arg/Arg, 28% were Arg/Gln, and 11% were Gln/Gln. Among the controls, 50% were Arg/Arg, 38% were Arg/Gln, and 12% were Gln/Gln. There was no difference in the distribution of XRCC1 genotypes or the frequencies of the Arg (75% versus 69%) and Gln (25% versus 31%) alleles between the lung cancer patients and controls. Our results suggest that the XRCC1 gene Arg399Gln polymorphism is not associated with an increased risk for the development of lung cancer in Turkish patients.

Statistical Shape Analysis of Nose in Turkish Young Adults

There are several anthropometric studies regarding the nose, however none of them involves data about a statistical shape analysis. In this study, a landmark-based geometric morphometric technique was used to analyze the nasal shapes in a young Turkish adult population. A population of 75 female and 75 male volunteer Turkish young adults whose ages ranged 18-39 years (24.82 ± 5.64 year) was examined. The stratified sampling method was used to determine the subjects according to the seven main geographic regions of Turkey. All data was obtained from standardized digital photographic images taken from anterior, lateral and inferior aspects by using standard anthropometric measurement methods. Euclidean Distance Matrix Analysis (EDMA) is used to calculate all possible linear distances among landmarks by creating matrixes for each subject. Today, the anthropometric methods and surgical practice intersected at a point to treat the congenital or post-traumatic facial disfigurements in various racial or ethnic groups. Rhinoplasty surgeons require access to facial databases based on accurate anthropometric measurements to perform optimum correction in both sexes. There should be some points brought to mind during the cosmetic nasal surgery for men because of different expectations, which is not technically different from the one for women. This study is a way to clarify these important points and a basis for further clinical studies enhancing the plans of the corrective surgery.

The relationship between perimesencephalic subarachnoid hemorrhage and deep venous system drainage pattern and calibrations.

BACKGROUND AND PURPOSE The purpose of this study is to investigate the relationship between Rosenthal basal vein (BVR) type and diameter and perimesencephalic nonaneurysmal subarachnoid hemorrhage (P-SAH). MATERIALS AND METHODS Aneurysmal subarachnoid hemorrhage (A-SAH), P-SAH, and control groups were evaluated, and BVRs were classified by type. BVR diameters in patients were measured. RESULTS There was a statistically significant difference of BVR drainage types between groups (P=.002). BVR diameters of patients with normal drainage pattern in P-SAH group were significantly smaller than those in both other groups (P<.001). CONCLUSION There is a relationship between P-SAH and BVR primitive drainage type. P-SAH risk increases in parallel with decreasing caliber of BVR in patients with normal drainage pattern.

Assessment of third ventriculostomy patency with the 3D-SPACE technique: a preliminary multicenter research study

OBJECT The goal of this study was to determine the value of the 3D sampling perfection with application-optimized contrasts using different flip-angle evolutions (3D-SPACE) technique in the evaluation of endoscopic third ventriculostomy (ETV) patency. METHODS Twenty-six patients with ETV were examined using 3-T MRI units. Sagittal-plane 3D-SPACE with variant flip-angle mode, 3D T1-weighted (T1W), and 3D heavily T2-weighted (T2W) images were obtained with isotropic voxel sizes. Also, sagittal-axial plane phase-contrast cine (PC)-MR images were obtained. The following findings were evaluated: diameters of stoma and third ventricle, flow-void sign on 3D-SPACE and PC-MR images, integrity of the third ventricle on heavily T2W images, and quantitative PC-MRI parameters of the stoma. Obtained sequences were evaluated singly, in combination with one another, and all together. RESULTS The mean area, flow, and velocity values measured at the level of stoma in patients with patent stoma were significantly higher than those measured in patients with closed stoma (p < 0.05). There was significant correlation among PC-MRI, 3D-SPACE, and 3D heavily T2W techniques regarding assessment of ETV patency (p < 0.001). The 3D-SPACE technique provided the lowest rate of ambiguous results. CONCLUSIONS The 3D-SPACE technique seems to be the most efficient one for determination of ETV patency. The authors suggest the use of 3D-SPACE as a stand-alone first-line sequence in addition to routine brain MRI protocols in assessing patients with ETV, thereby decreasing scan time and reserving the use of a combination of additional sequences such as PC-MRI and 3D heavily T2W images in suspicious or complex cases.