Researcher:
Altınmakas, Emre

Profile Picture
ORCID

Job Title

Other

First Name

Emre

Last Name

Altınmakas

Name

Name Variants

Altınmakas, Emre

Email Address

Birth Date

Filters

2018 - 201952020 - 202217

Advanced Search

Filter by

Settings

Researcher Of Publications: search.filters.isAuthorOfPublication.994249a2-6407-4773-92ce-c69d839ff03b

Search Results

Now showing 1 - 10 of 22
  • Placeholder
    PublicationMetadata only
    Incidentally detected perineal aggressive angiomyxoma in an asymptomatic patient with uterine leiomyomas
    (Taylor & Francis Inc, 2021) Temur, Muzaffer; N/A; Altınmakas, Emre; Doğan, Hakan; Güneyli, Serkan; Other; Researcher; Faculty Member; School of Medicine; School of Medicine; School of Medicine; 143682; 327614; 36622
    N/A
  • Placeholder
    PublicationMetadata only
    CT and 18F- FDG-PET-CT findings in secondary adrenal lymphoma with pathologic correlation
    (Elsevier Science Inc, 2019) Üçışık-Keser, Fehime Eymen; Medeiros, L. Jeffrey; Ng, Chaan Sş; N/A; Altınmakas, Emre; Other; School of Medicine; Koc University Hospital; 143682
    Rationale and Objective: To evaluate computed tomography (CT) and positron emission tomography-computed tomography (PET-CD imaging manifestations of lymphomas secondarily involving the adrenal gland. Materials and Methods: Seven patients (Five men, two women; median age [range], 66 years [34-75 years]) with pathologically proven adrenal lymphoma were assessed retrospectively. Clinical findings, prior history of lymphoproliferative malignancy, CT (n = 7) and fludeoxyglucose positron emission tomography-computed tomography (F-18-FDG-PET-CT) (n = 6) features were analyzed. Results: Six cases were diffuse large B-cell lymphoma, and one case was peripheral T-cell lymphoma. The longest diameter of the lesions ranged from 3.2 to 6.6 cm (median 4.3 cm). Six lesions were well-defined and one lesion was ill-defined. In five cases, an adreniform shape was preserved. No lesions contained fat, calcification or hemorrhage. Two lesions had necrosis on CT. Median (range) unenhanced CT density of six lesions was 31.8 (29.2-35.2) Hounsfield units. Following administration of IV contrast media (n = 6), three lesions enhanced homogenously whereas three enhanced heterogeneously. The median increase in attenuation was 35.1 Hounsfield units. Two patients had 15-minute delayed CT and they both demonstrated limited wash-out consistent with nonadenoma. Six patients had fludeoxyglucose positron emission tomography-computed tomography(F-18-FDG-PET-CT) and all lesions were fludeoxyglucose (FDG) avid with a median SUV(max )of 18.6 (range: 10.3-49.2). Conclusion: Secondary adrenal lymphomas usually manifest as, large (>3 cm), well-defined, homogenously or slightly heterogeneously enhancing masses on CT with preserved adreniform shape. These lesions tend to show limited wash-out and high fludeoxyglucose (FDG) uptake.
  • Placeholder
    PublicationMetadata only
    Combining washout and noncontrast data from adrenal protocol CT: improving diagnostic performance
    (Elsevier, 2018) Ng, Chaan S.; Wei, Wei; Ghosh, Payel; Li, Xiao; Grubbs, Elizabeth G.; Perrier, Nancy A.; Prieto, Victor G.; Lee, Jeffrey E.; Hobbs, Brian P.; N/A; Altınmakas, Emre; Other; School of Medicine; 143682
    Rationale and Objectives: To determine if combination of washout and noncontrast data from delayed adrenal computed tomography (CT) improves diagnostic performance, and demonstration of an optimizing analytical framework. Materials and Methods: This retrospective study consisted of 97 adrenal lesions, in 96 patients, with pathologically proven adrenal lesions (75 benign; 22 malignant), who had undergone noncontrast, portal- and approximate 15-minute delayed-phase CT. Lesion CT attenuations (Hounsfield units [HU]) during each phase, and “absolute” and “relative” percent enhancement washouts (APEW and RPEW) were assessed. The optimum combination of sequential parameters and thresholds was determined by recursive partitioning analysis; resultant diagnostic performance was compared to commonly applied single-parameter criteria for malignancy (noncontrast > 10 HU, APEW < 60%, RPEW < 40%). Results: The above single-parameter criteria yielded sensitivities, specificities, and accuracies for malignancy of 100.0%, 41.3%, and 54.6%; 97.9%, 61.3%, and 69.1%; and 96.6%, 74.7%, and 78.4%, respectively. Recursive partitioning analysis identified noncontrast ≥24.75 HU, with subsequent APEW ≤63.49%, as the optimum sequential parameter-threshold combination, which yielded increased sensitivity, specificity, and accuracy of 100.0%, 85.3%, and 90.7%, respectively. Discrimination using the combined sequential classifier yielded statistically significant improvements in accuracy when compared to the above conventional single-parameter criteria (all P ≤.039). Conclusion: Sequential application of noncontrast and washout criteria from delayed contrast-enhanced adrenal CT can improve diagnostic performance beyond that of commonly applied single-parameter criteria. Validation of the sequential ordering and refinement of the specific threshold values warrant further study.
  • Placeholder
    PublicationMetadata only
    Abbreviated liver magnetic resonance imaging protocols and applications
    (Elsevier, 2022) Taouli, Bachir; N/A; Altınmakas, Emre; Other; School of Medicine; 143682
    Abbreviated magnetic resonance imaging (AMRI) approach became a hot topic in liver imaging recently. Different AMRI protocols including noncontrast AMRI (NC-AMRI), hepatobiliary-AMRI (HBP-AMRI) using gadoxetic acid, and dynamic-AMRI (Dyn-AMRI) using extracellular contrast agent, have been described in the literature. In this review, the use of these AMRI approaches in various indications including hepatocellular carcinoma (HCC) screening and surveillance in chronic liver disease; fat, iron, and fibrosis screening and assessment in nonalcoholic fatty liver disease (NAFLD); and finally liver metastasis screening and surveillance in patients with colorectal cancer are summarized.
  • Placeholder
    PublicationMetadata only
    Performance of native and gadoxetate-enhanced liver and spleen t-1 mapping for noninvasive diagnosis of clinically significant portal hypertension: preliminary results
    (Springer, 2022) Bane, Octavia; Hectors, Stefanie J.; Issa, Rayane; Carbonell, Guillermo; Abboud, Ghadi; Schiano, Thomas D.; Thung, Swan; Fischman, Aaron; Kelly, Matthew D.; Friedman, Scott L.; Kennedy, Paul; Taouli, Bachir; N/A; Altınmakas, Emre; Other; School of Medicine; Koc University Hospital; 143682
    Purpose In this preliminary study, our aim was to assess the utility of quantitative native-T1 (T1-pre), iron-corrected T1 (cT1) of the liver/spleen and T1 mapping of the liver obtained during hepatobiliary phase (T1-HBP) post-gadoxetate disodium, compared to spleen size/volume and APRI (aspartate aminotransferase-to-platelet ratio index) for noninvasive diagnosis of clinically signifcant portal hypertension [CSPH, defned as hepatic venous pressure gradient (HVPG)≥10 mm Hg]. Methods Forty-nine patients (M/F: 27/22, mean age 53y) with chronic liver disease, HVPG measurement and MRI were included. Breath-held T1 and cT1 measurements were obtained using an inversion recovery Look-Locker sequence and a T2* corrected modifed Look-Locker sequence, respectively. Liver T1-pre (n=49), spleen T1 (obtained pre-contrast, n=47), liver and spleen cT1 (both obtained pre-contrast, n=30), liver T1-HBP (obtained 20 min post gadoxetate disodium injection, n=36) and liver T1 uptake (ΔT1, n=36) were measured. Spleen size/volume and APRI were also obtained. Spearman correlation coefcients were used to assess the correlation between each of liver/spleen T1/cT1 parameters, spleen size/volume and APRI with HVPG. ROC analysis was performed to determine the performance of measured parameters for diagnosis of CSPH. Results There were 12/49 (24%) patients with CSPH. Liver T1-pre (r=0.287, p=0.045), liver T1-HBP (r=0.543, p=0.001), liver ΔT1 (r= −0.437, p=0.008), spleen T1 (r=0.311, p=0.033) and APRI (r=0.394, p=0.005) were all signifcantly correlated with HVPG, while liver cT1, spleen cT1 and spleen size/volume were not. The highest AUCs for the diagnosis of CSPH were achieved with liver T1-HBP, liver ΔT1 and spleen T1: 0.881 (95%CI 0.76–1.0, p=0.001), 0.852 (0.72–0.98, p=0.002) and 0.781 (0.60–0.95, p=0.004), respectively. Conclusion Our preliminary results demonstrate the potential of liver T1 mapping obtained during HBP post gadoxetate disodium for the diagnosis of CSPH. These results require further validation.
  • Placeholder
    PublicationMetadata only
    Diagnostic performance of adrenal CT in the differentiation of adenoma and pheochromocytoma
    (Sage Publications Ltd, 2020) Perrier, Nancy D.; Grubbs, Elizabeth G.; Lee, Jeffrey E.; Prieto, Victor G.; Ng, Chaan S.; Altınmakas, Emre; Other; School of Medicine; 143682
    Background Differentiation of adenoma and pheochromocytoma on computed tomography (CT) may be problematic. Purpose To investigate if adenoma and pheochromocytoma can be differentiated with adrenal CT. Material and Methods A total of 147 pathologically proven adrenal masses (119 adenomas, 28 pheochromocytomas) that had undergone adrenal CT were retrospectively evaluated. Lesion attenuation on unenhanced phase (UEP), portal phase (PP), 15-min delayed phase (DP), absolute/relative percentage enhancement wash-out (APEW/RPEW), and qualitative features were recorded. Student's t-test for parametric data, Mann-Whitney U test for non-parametric data, and Fisher's exact test for categorical data were used. Diagnostic performance of CT attenuation was assessed by area under the curve (AUC) of the receiver operating characteristics. Results APEW of adenomas was not significantly different from pheochromocytomas; 68.4% and 59% (P = 0.284). Adenomas had significantly higher RPEW; 57.3% vs. 37.4% (P = 0.004). of pheochromocytomas, 50% met APEW >60% or RPEW >40% criteria, and therefore were misclassified as adenoma on wash-out CT. of those, 80% (4/5) were < 3 cm. UEP, PP, and DP attenuations of pheochromocytomas were significantly higher than adenomas; however, they were overlapping. AUC for UEP, PP, and DP was 0.906, 0.784, and 0.926, respectively. Larger pheochromocytomas were more likely to contain necrosis compared to smaller pheochromocytomas and adenomas; 41.6% vs. 12.5% vs. 3%. Homogeneous enhancement was seen in 25% of pheochromocytomas and 49% of adenomas (P = 0.018). No significant difference was found in terms of lesion borders and presence of fat/calcification (P > 0.05). Conclusions A considerable percentage of pheochromocytomas, especially smaller ones, demonstrate adenoma-like wash-out on CT. Heterogeneous enhancement, higher attenuation, and necrosis are more suggestive of pheochromocytoma.
  • Placeholder
    PublicationMetadata only
    Computed tomography findings in adrenocortical carcinoma
    (Selçuk Üniversitesi Tıp Fakültesi, 2021) N/A; Altınmakas, Emre; Other; School of Medicine; 143682
    Objective: To evaluate computed tomography (CT) imaging manifestations of adrenocortical carcinomas (ACC). Materials and Methods: Qualitative, and quantitative CT findings of 15 patients (Eight women, seven men; median age [range], 53 years [31-74 years]) with 15 pathologically proven ACCs were retrospectively analyzed. Lesions' functional status were captured through clinical notes. Results: Pathologic diagnosis was based on either surgery (n=12) or surgical biopsy (n=3). Nine lesions were functioning (60%, androgen [n=5] or cortisol [n=4]) and 6 lesions were non-functioning (40%). In qualitative CT analysis, 13 (93%), 3 (20%), and 1 (7%) lesion had necrosis, calcification and macroscopic fat, respectively. All lesions showed well-defined borders and heterogeneous enhancement. Median [range] density on precontrast, arterial phase, portal phase, and 15-minute delay phase were 34 HU (22-41 HU), 46 HU (27-65 HU), 60 HU (29-90 HU), and 48 HU (28-64 HU), respectively. Nine patients had 15-minute delay phase available. Median (range) absolute and relative percentage of enhancement wash-out (APEW and RPEW) values were 48.8% (-3.8-62.5%) and 21% (-1.5-30.8%). Only one lesion had an APEW above %60. Conclusion: ACCs usually manifest as, large (>6cm), well-defined, heterogeneously enhancing, necrotic masses on CT. These lesions may include calcification or macroscopic fat and tend to show limited wash-out on delay phase CT. /Öz: Amaç: Adrenal kortikal karsinomun (AKK) Bilgisayarlı Tomografi (BT) görüntüleme özelliklerini araştırmak. Gereç ve yöntem: Patolojik olarak AKK tanısı almış 15 hastanın (K/E: 8/7, ortanca [aralık]: 53 yıl [31-74 yıl]) kalitatif ve kantitatif BT bulguları retrospektif olarak değerlendirildi. Lezyonların fonksiyonel durumlarına klinik notlardan ulaşıldı. Bulgular: Hastaların patolojik tanısı cerrahi (n=12) veya cerrahi eşliğinde biyopsi (n=3) ile konulmuştu. 9 lezyon (%60) fonksiyonel, 6 lezyon (%40) nonfonksiyoneldi. Fonksiyonel lezyonların 5’i androjen, 4’ü kortizon üretmekteydi. Kalitatif değerlendirmede 13 lezyon (%93) nekroz, 3 lezyon (%20) kalsifikasyon ve 1 lezyon (%7) makroskobik yağ içeriyordu. Lezyonların tamamı iyi sınırlı olup heterojen kontrastlanmaktaydı. Lezyonların ortanca (aralık) boyutu 9,7 cm (6,3-18 cm) idi. Prekontrast, arteriyel faz, portal faz ve geç faz ortanca (aralık) dansite değerleri sırasıyla şöyleydi: 34 HU (22-41 HU), 46 HU (27-65 HU), 60 HU (29-90 HU), 48 HU (28-64 HU). 9 hastada 15. dakika geç faz elde olunmuştu. Ortanca (aralık) mutlak (MKYY) ve bağıl (BKYY) kontrast yıkanma yüzdeleri sırasıyla şöyleydi: %48,8 (%-3,8-62,5) ve %21 (%-1,5-30,8). Sadece bir lezyonun MKYY değeri %60’in üzerindeydi. Sonuç: AKK’lar BT’de genellikle büyük (>6cm), iyi sınırlı, heterojen kontrastlanan, nekrotik kitleler şeklinde görülür. Makroskobik yağ ve kalsifikasyon içerebilir ve geç faz imajlarda sınırlı kontrast yıkanması gösterirler.
  • Placeholder
    PublicationMetadata only
    Differentiation of malignant and benign adrenal lesions with delayed CT: multivariate analysis and predictive models
    (Amer Roentgen Ray Soc, 2018) Ng, Chaan S.; Wei, Wei; Li, Xiao; Ghosh, Payel; Perrier, Nancy A.; Grubbs, Elizabeth; Prieto, Victor G.; Lee, Jeffrey E.; Hobbs, Brian P.; Altınmakas, Emre; Other; School of Medicine; 143682
    Objective: The purpose of this study is to identify imaging and patient parameters that affect the diagnostic performance of delayed contrast-enhanced CT for distinguishing malignant from benign adrenal lesions larger than 1 cm in adult patients and to derive predictive models. Materials and Methods: This retrospective study assessed 97 pathologically proven adrenal lesions that had undergone unenhanced, portal venous, and 15-minute delayed CT. Quantitatively, single-parameter evaluations of lesion attenuation (in Hounsfield units) and absolute percentage enhancement washout (APEW) and relative percentage enhancement washout (RPEW) were performed. In addition, descriptive CT features (lesion size, margin definition, heterogeneity vs homogeneity, fat, and calcification) and patients' demographic characteristics and medical history of malignancy were evaluated for association with lesion status using multiple logistic regression with stepwise model selection. Areas under the ROC curve (A(z)) were determined for univariate and multivariate analyses. Leave-one-lesion-out cross-validation was applied to ascertain the predictive performance of single-parameter and multivariate evaluations. Results: The A(z) values for unenhanced attenuation, portal venous attenuation, delayed attenuation, APEW, and RPEW were 0.835, 0.534, 0.847, 0.792, and 0.871, respectively. Multivariate analyses revealed that portal venous attenuation, delayed attenuation, and APEW were significant features, with an A(z) of 0.923 when combined. The addition of the descriptive CT features increased the A(z) to 0.938; patient age and a history of malignancy were additional significant factors, increasing the A(z) to 0.956 and 0.972, respectively. The combined predictive classifier yielded 89% accuracy under cross-validation, compared with the best commonly applied single-parameter evaluation (77% for RPEW < 40%). Conclusions: Multivariate imaging evaluation applied to delayed contrast-enhanced CT alone, with or without patient characteristics, improves diagnostic performance for characterizing adrenal lesions beyond those of single-parameter evaluations. Predictive formulas assessing the probabilities of lesion benignity or malignancy are provided.
  • Placeholder
    PublicationMetadata only
    Utility of intermediate-delay washout CT images for differentiation of malignant and benign adrenal lesions: a multivariate analysis
    (Amer Roentgen Ray Soc, 2018) Ng, Chaan S.; Wei, Wei; Li, Xiao; Ghosh, Payel; Perrier, Nancy A.; Grubbs, Elizabeth; Prieto, Victor G.; Lee, Jeffrey E.; Hobbs, Brian P.; Altınmakas, Emre; Other; School of Medicine; 143682
    Objective: The objective of this study was to identify features that impact the diagnostic performance of intermediate-delay washout CT for distinguishing malignant from benign adrenal lesions. Materials and Methods: This retrospective study evaluated 127 pathologically proven adrenal lesions (82 malignant, 45 benign) in 126 patients who had undergone portal venous phase and intermediate-delay washout CT (1-3 minutes after portal venous phase) with or without unenhanced images. Unenhanced images were available for 103 lesions. Quantitatively, lesion CT attenuation on unenhanced (UA) and delayed (DL) images, absolute and relative percentage of enhancement washout (APEW and RPEW, respectively), descriptive CT features (lesion size, margin characteristics, heterogeneity or homogeneity, fat, calcification), patient demographics, and medical history were evaluated for association with lesion status using multiple logistic regression with stepwise model selection. Area under the ROC curve (A(z)) was calculated from both univariate and multivariate analyses. The predictive diagnostic performance of multivariate evaluations was ascertained through cross-validation. Results: A(z) for DL, APEW, RPEW, and UA was 0.751, 0.795, 0.829, and 0.839, respectively. Multivariate analyses yielded the following significant CT quantitative features and associated A(z) when combined: RPEW and DL (A(z) = 0.861) when unenhanced images were not available and APEW and UA (A(z) = 0.889) when unenhanced images were available. Patient demographics and presence of a prior malignancy were additional significant factors, increasing A(z) to 0.903 and 0.927, respectively. The combined predictive classifier, without and with UA available, yielded 85.7% and 87.3% accuracies with cross-validation, respectively. Conclusion: When appropriately combined with other CT features, washout derived from intermediate-delay CT with or without additional clinical data has potential utility in differentiating malignant from benign adrenal lesions.
  • Placeholder
    PublicationMetadata only
    Diagnostic ability of Ga-68 PSMA PET to detect dominant and non-dominant tumors, upgrading and adverse pathology in patients with PIRADS 4–5 index lesions undergoing radical prostatectomy
    (Springernature, 2021) Kilic, Mert; Vural, Metin; N/A; Köseoğlu, Ersin; Kordan, Yakup; Şal, Oğuzhan; Seymen, Hülya; Kiremit, Murat Can; Armutlu, Ayşe; Baydar, Dilek Ertoy; Altınmakas, Emre; Falay, Fikri Okan; Canda, Abdullah Erdem; Balbay, Mevlana Derya; Demirkol, Mehmet Onur; Esen, Tarık; Faculty Member; Faculty Member; Undergraduate Student; Teaching Faculty; Faculty Member; Teaching Faculty; Faculty Member; Other; Teaching Faculty; Faculty Member; Faculty Member; Faculty Member; Faculty Member; School of Medicine; School of Medicine; School of Medicine; School of Medicine; School of Medicine; School of Medicine; School of Medicine; School of Medicine; School of Medicine; School of Medicine; School of Medicine; School of Medicine; School of Medicine; Koç University Hospital; N/A; N/A; N/A; N/A; N/A; N/A; N/A; N/A; N/A; N/A; N/A; 350876; 157552; N/A; 350778; 222920; 133567; 8025; 143682; 246484; 116202; 153320; 196946; 50536
    Background To evaluate the additive role of Ga-68 PSMA PET as a primary staging tool in patients bearing prostate cancer in single PIRADS 4 or 5 index lesions. Methods Eighty-one biopsy-naive patients with preoperative mpMRI and Ga-68 PSMA PET who underwent radical prostatectomy (RP) were evaluated retrospectively. Forty-nine patients had PIRADS 4 and 32 had PIRADS 5 index lesions. The localization, grade, and volumetric properties of dominant (DT) and non-dominant tumors (NDT) in RP were compared to the index lesions of mpMRI and Ga-68 PSMA PET. Results The median age and PSA level were 62 (IQR; 59-69) years and 7 (IQR; 2-8) ng/ml, respectively. Ga-68 PSMA PET detected DTs in 100% of the patients including 13 patients in whom mpMR failed. In 45 patients an NDT was reported in RP. Ga-68 PSMA PET accurately detected NDT in 24 of 45 (53.3%) patients. Six patients (12.2%) in PIRADS 4 and 8 (25%) in PIRADS 5 group showed upgrading. In PIRADS 4, Ga-68 PSMA PET localized DT in all patients with upgraded tumors whereas mpMRI missed exact location in 2 of 6 (33.3%). In PIRADS 5 both mpMRI and Ga-68 PSMA PET accurately located all DTs. Overall detection rates of extracapsular extension (ECE) and seminal vesicle invasion (SVI) by mpMRI were 51.1% and 53.8%, respectively. Ga-68 PSMA PET detected ECE and SVI in 27.9% and 30.7%, respectively. When mpMRI and Ga-68 PSMA PET were used in combination detection rates of ECE and SVI increased to 65.1 and 61.5%. Ga-68 PSMA PET-detected six of ten patients with positive lymph nodes whereas mpMRI could not identify any. Conclusions Ga-68 PSMA PET has a better diagnostic accuracy in detecting DT, NDT, upgrading, adverse pathology in patients with PIRADS 4 index lesions. However, mpMRI better predicted ECE and SVI than Ga-68 PSMA PET.