Yazar "Karatag, Gulden Yenice" seçeneğine göre listele

Listeleniyor 1 - 3 / 3
  • [ X ]
    Öğe
    CAN MAGNETIC RESONANCE SPECTROSCOPY ADEQUATELY DIFFERENTIATE NEOPLASTIC FROM NON-NEOPLASTIC AND LOW-GRADE FROM HIGH-GRADE LESIONS IN BRAIN MASSES?
    (Marmara Univ, Fac Medicine, 2010) Karatag, Ozan; Karatag, Gulden Yenice; Uysal, Ender; Can, S. Meltem; Erturk, Mehmet; Basak, Muzaffer
    Objective: The aim of this study was to evaluate the usefulness of Magnetic Resonance Spectroscopy in the differential diagnosis of brain lesions. Materials and Methods: Forty-six patients with cerebral lesions were examined by Magnetic Resonance Spectroscopy. Choline, creatine, N-acetyl aspartate and lipid-lactate peaks were evaluated. Forty of the 46 patients underwent stereotactic biopsy or surgery. Histopathological results were compared with the Magnetic Resonance Spectroscopy results. Results: The Choline / N-acetyl aspartate ratio had the highest sensitivity (87.2%) in neoplastic versus nonneoplastic differentiation and the specificities of the Choline / Creatine, Choline / N-acetyl aspartate and Choline+Creatine / N-acetyl aspartate ratios were found to be 100%. Choline / Creatine ratios showed the highest sensitivity (95.7%) in low-grade versus high-grade differentiation and specificities of Choline / N-acetyl aspartate, Choline+Creatine / N-acetyl aspartate ratios and lipid-lactate levels were found to be 100%. Consequently, a value of Choline / Creatine > 2.2 and an accompanying lipid-lactate peak differentiated neoplasms as low-grade versus high-grade with a sensitivity of 100% (82.2-100%) and a specificity of 100% (71.7-100%). Conclusion: The presence of elevated Choline and decreased N-acetyl aspartate levels are effective in the differetiation of neoplastic versus non-neoplastic lesions with high sensitivity and specificity. A proposed ratio of Choline / Creatine > 2.2 and an accompanying lipid-lactate peak provide valuable information in differentiating low-grade from high-grade lesions.
  • [ X ]
    Öğe
    Invasive lobular carcinoma of the breast: mammographic and sonographic evaluation
    (Aves, 2011) Albayrak, Zeynep Kirkali; Onay, Hulya Kapran; Karatag, Gulden Yenice; Karatag, Ozan
    PURPOSE To evaluate the efficacy of mammography and sonography together in the assessment of patients with pure invasive lobular carcinomas (ILCs) of the breast. MATERIALS AND METHODS We retrospectively reviewed 38 cases of pure invasive lobular carcinomas of the breast. The tumors were evaluated both mammographically and sonographically. The mammographic images were reviewed by two experienced mammographers. All patients underwent surgical management. Histopathologic assessments were made by experienced breast pathologists. RESULTS On physical examination, six tumors (15.7%) showed no clinical findings. The most common mammographic result was a spiculated mass or architectural distortion (42%). Eleven lesions (29%) were mammographically negative. Five cases (13%) showed pleomorphic or heterogeneous calcifications that were compatible with Breast Imaging Reporting and Data System (BI-RADS) 4 or 5. The most common sonographic result was a hypoechoic mass with or without shadowing (60.5%). Four tumors (10.5%) were sonographically invisible. Two cases (5%) were negative, and 25 cases (65.8%) were positive in both modalities. The overall sensitivity was 71.05% for mammography and 89.47% for sonography. The number of tumors detected by either of these two modalities was 36, and the overall sensitivity was 94.73%. CONCLUSION Mammography and ultrasonography are useful imaging methods in the evaluation of invasive lobular carcinoma. Because of the low rate of suspicious calcifications and low density of lesions, the false-negative rate tends to be high for these tumors. With the use of sonography and mammography together, invasive lobular carcinomas can be detected with a sensitivity of 94.73%. We recommend additional sonographic evaluations for all patients, especially those with dense breast tissue with or without positive mammographic findings.
  • [ X ]
    Öğe
    The ability of phased-array MRI in preoperative staging of primary rectal cancer: correlation with histopathological results
    (Turkish Soc Radiology, 2012) Karatag, Ozan; Karatag, Gulden Yenice; Ozkurt, Huseyin; Degirmenci, Hulya Kurtul; Avlanmis, Omer; Basak, Muzaffer; Baykan, Adil
    PURPOSE This study evaluated the accuracy of phased-array magnetic resonance imaging (MRI) for preoperative local tumor staging in primary rectal cancer and emphasized the importance of the preoperative differentiation of T2 tumors from T3 tumors so the appropriate treatment can be applied. MATERIALS AND METHODS Twenty-four patients with primary rectal cancer were examined preoperatively using 1.5 T MRI with a phased-array coil. Multiplanar T2-weighted images were obtained. Rectum anatomy, depth of tumor invasion, mesorectal involvement and lymph nodes were assessed. All patients underwent radical surgery. The histological sections were evaluated microscopically. The correlation of magnetic resonance imaging and histopathology was assessed using the kappa statistic. Overstaging with MRI was compared with Fischer's exact test. RESULTS Histopathological examination of the tumors revealed adenocarcinoma. When the tumors were staged, there was one patient with a pT1 tumor, six patients with pT2 tumors, and 17 patients with pT3 tumors. Using MRI, four patients with pT2 were overstaged as T3, and one patient with pT3 was overstaged as T4. In the remaining cases (one pT1, two pT2, and 16 pT3), MRI correctly assessed the stage of transmural invasion. The accuracy of T staging and metastatic lymph node detection with MRI was calculated as 79.2% and 58.5%, respectively. CONCLUSION Phased-array MRI is a valuable technique for the preoperative staging of rectal cancer, especially in the differentiation of T2 and T3 tumors.