Haldun Baris Diren
Hacettepe University, Radiology, Emeritus
- He was born in İstanbul (Turkey) in 1957. He achieved Medical Doctor degree in 1981 (Hacettepe University, Ankara, Tu... moreHe was born in İstanbul (Turkey) in 1957. He achieved Medical Doctor degree in 1981 (Hacettepe University, Ankara, Turkey). He continued his Radiology training in Radiology Department of Medicine Faculty at Hacettepe University. He got the Radiologist degree in 1986 and he was assigned as founding chair of radiology department to Ondokuz Mayis University (Samsun, Turkey). He got the degree of Associate Professor in Radiology in 1988. He was assigned to Dokuz Eylül University (Izmir, Turkey) in 1989 for running the first MRI unit in Turkey. During his military services in Gülhane Military Academy of Medicine (Ankara, Turkey), he worked for setting up the first high field MRI unit in Turkey, in 1992. Dr. Diren also took important roles in establishment of some of major hospitals in Turkey. He was one of the founding member of Sevgi Hospital (Ankara, Turkey) in 1993, and he worked as chief of staff for first 3 years. He founded the first “day hospital” in Turkey, in 1996. He worked as project manager in the designing and construction of İstanbul Memorial Hospital in 2000, and worked as Medical Director for first 2 years. He was assigned as consultant manager by Ministry of Health for setting up the re-construction of Siyami Ersek Chest Surgery Hospital (Istanbul, Turkey) in 2002. He worked as project manager in the designing and construction of Mesa Hospital (Ankara, Turkey) in 2002. He got the Professor degree in Radiology in 2003 and worked as the head of Radiology Department in Ondokuz Mayıs University (Samsun, Turkey) between the years 2003-2008. He also worked as Vice Rector in Ondokuz Mayis University (Samsun, Turkey) between the years 2004-2008. After his retirement in 2008, he started to work in Medicana International Ankara Hospital (Ankara, Turkey) as the head of Radiology Department and Medical Director. He is married and has 2 children.
Dr. Diren had also taken active roles in the development of national healthcare strategies in Turkey. ISO 9000 quality certification at healthcare institutions was first conducted by him in Turkey (Sevgi Hospital, 1994). The first international accreditation certification in Turkey was also achieved by Istanbul Memorial Hospital where he was the Medical Director (Joint Commission Accreditation, 2002). Dr. Diren has over 350 scientific studies and 14 textbooks on Radiology. Due to his studies on radiology, he has gained three times scientific awards and two times honorary awards.edit
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... MR görüntülerinde ortaya konabilir ve karakteristik olarak artrms sinyal yogunlugu seklinde T2 agirhkh serilerde ortaya konabilir. ... Hiperakut bir miyokardiyal iskemide bu teknikle yapilacak incelemelerde, "no-reflow"... more
... MR görüntülerinde ortaya konabilir ve karakteristik olarak artrms sinyal yogunlugu seklinde T2 agirhkh serilerde ortaya konabilir. ... Hiperakut bir miyokardiyal iskemide bu teknikle yapilacak incelemelerde, "no-reflow" zonlan infarktin subepikardiyal kenan ile kargilagtinldiginda ...
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... (0:07) Hacettepe'den Uğur Acar tepkisi. (0:06) Hemşire adayı, ehliyetsiz sürücü kurbanı oldu. (0:04) Erdoğan hastanelere tepkili. (13:27) İkinci yüz naklini yapan doktor: Hepimizin yüzü gibi oldu. ... Dr. Kemal BAYSAL, Yrd. Doç.... more
... (0:07) Hacettepe'den Uğur Acar tepkisi. (0:06) Hemşire adayı, ehliyetsiz sürücü kurbanı oldu. (0:04) Erdoğan hastanelere tepkili. (13:27) İkinci yüz naklini yapan doktor: Hepimizin yüzü gibi oldu. ... Dr. Kemal BAYSAL, Yrd. Doç. Dr. Barış DİREN, Prof. Dr. Mikail YÜKSEL, Prof. ...
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Background: Myocardial bridging (MB) is a congenital anomaly in which a segment of coronary artery is surrounded by myocardium. Purpose: To investigate the correlation between muscle thickness over the tunneled coronary artery (depth) in... more
Background: Myocardial bridging (MB) is a congenital anomaly in which a segment of coronary artery is surrounded by myocardium. Purpose: To investigate the correlation between muscle thickness over the tunneled coronary artery (depth) in MB and the presence of milking effect (ME) and systolic narrowing ratio in catheter angiography (CA). Material and Methods: The records of 36 patients who underwent a coronary computed tomography angiography (CTA) and following CA examination for suspicious ischemic coronary artery disease, between March 2005 and September 2007, were retrospectively evaluated. According to the depth of MB on CTA, patients were grouped into four groups: group 1, <1 mm; group 2, 1– <2 mm; group 3, 2– <4 mm; group 4, ≥4 mm. The presence of milking effect, systolic narrowing ratio, and atherosclerotic stenosis at CA were recorded. CTA and CA results were then compared to evaluate the correlation. Results: In total, ME was found in 15 arteries at CA (42%). There...
Research Interests: Radiology, Nuclear medicine, Medicine, Electrocardiography, Humans, and 14 moreFemale, Male, Three Dimensional Imaging, Clinical Sciences, Aged, Middle Aged, Coronary Angiography, Adult, ACTA, Retrospective Studies, Angina pectoris, Coronary Artery Disease, X ray Computed Tomography, and Severity of Illness Index
... KÎTLELERlN BÎLGlSnYARLI T0M0GRAFÎSÎ: 53 OLGU * Dr.Aii Demircl**, Dr.H.Bari§ Diren***5 Dr.Mustafa B. Selçiik****, Dr.Korkut Tarlakazan****, Dr.Kuddusi Ccngiz***** Dr.A.Cemll Aykin***** ÖZET Bu çaliçaeda, Ï986 ile 1988 tarihleri... more
... KÎTLELERlN BÎLGlSnYARLI T0M0GRAFÎSÎ: 53 OLGU * Dr.Aii Demircl**, Dr.H.Bari§ Diren***5 Dr.Mustafa B. Selçiik****, Dr.Korkut Tarlakazan****, Dr.Kuddusi Ccngiz***** Dr.A.Cemll Aykin***** ÖZET Bu çaliçaeda, Ï986 ile 1988 tarihleri arasinda mediastinal kit le ön tanxsx alan ...
SUMMARY COMPUTED TOMOGRAPHY OF THE PRIMARY PULMONARY MALIGNANCIES AMD SOLITARY PULMONARY MODULES In this study computed tomographic (CT) findings of the 83 patients with solitary pulmonary nodule and who have been thought primary... more
SUMMARY COMPUTED TOMOGRAPHY OF THE PRIMARY PULMONARY MALIGNANCIES AMD SOLITARY PULMONARY MODULES In this study computed tomographic (CT) findings of the 83 patients with solitary pulmonary nodule and who have been thought primary pulmonary malignancy were evaluated. CT-guided transthoracic oeedle aspiration biopsy (TNAB) were also perfonned in 23 patients of this group. The values of CT and TNAB in primary pulmonary malignancy and solitary pulmonary nodules nave been discussed. OZET Calismamizda toraks bilgisayarli tomografi tetkikleri sira¬sinda primer pulmoner malignensi oldugu dusunulen veya soliter pulmoner nodulu olan 83 hasta incelendi. Bu grupta yer alan 23 hastaya bilgisayarli tomografi yol gostericiliginde transtorasik igne aspirasyon biopsisi uygulandi. Primer pulmoner malignensi ve soliter pulmoner nodullerde bilgisa¬yarli, tomografi ve transtorasik aspirasyon biopsisinin yeri tartisildi.
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... 0.001). Araştırma grubumuzu oluşturan olguların i Tsi artro· tom i teklifini kabul etmiş, bu olgulardaki klinik ön tanı, BT tanısı ve artrotomi bulguları Tablo-V&#x27;de sunulmuştur. . ... reference. Contemporary Orthopaedies,... more
... 0.001). Araştırma grubumuzu oluşturan olguların i Tsi artro· tom i teklifini kabul etmiş, bu olgulardaki klinik ön tanı, BT tanısı ve artrotomi bulguları Tablo-V&#x27;de sunulmuştur. . ... reference. Contemporary Orthopaedies, Bobit Publıshi ng, 19S6, g.
Nöroepitelyal kistler nadir görülen ve içerikleri homojen sv yo¤unlu¤unda, beyin-omurilik svsna (BOS) benzeyen kistlerdir. Kistlerin ço¤u asemptomatiktir ancak, bazen kitle etkisi ile epileptik nöbetler ya da hareket bozukluklar ile... more
Nöroepitelyal kistler nadir görülen ve içerikleri homojen sv yo¤unlu¤unda, beyin-omurilik svsna (BOS) benzeyen kistlerdir. Kistlerin ço¤u asemptomatiktir ancak, bazen kitle etkisi ile epileptik nöbetler ya da hareket bozukluklar ile ortaya çkabilirler. Genellikle tek baflna ...
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Objective: It has been advocated that a reduced injection volume with highly concentrated (1 M) contrast material can produce a sharper bolus peak and an increased intravascular first-pass gadolinium concentration when compared with the... more
Objective: It has been advocated that a reduced injection volume with highly concentrated (1 M) contrast material can produce a sharper bolus peak and an increased intravascular first-pass gadolinium concentration when compared with the use of a lower concentration (0.5 M). A higher concentration would also cause a reduction in dose. The purpose of our study was to test the use of a low dose (0.05 mmol/kg) of gadobutrol in magnetic resonance renography and angiogra-phy and compare the findings with a dose of 0.1 mmol/kg. Materials and Methods: One-hundred-thirty-four patients referred for magnetic resonance angiography for suspected renovascular disease participated in the study. Contrast enhanced MR renography and angiography were performed after administration of a bolus of 0.1 mmol/kg or 0.05 mmol/kg gadobutrol in random-ized patients. The relative signal intensity-time curves of the aorta, peripheral cortex and parenchyma, were obtained. Two radiologists evaluated the angiographic images and evaluated the quality of angiography. Results: The signal intensity with a low dose of gadobutrol was significantly lower in early phases, in the peripheral cortex (for 36, 54, 72 and 90 seconds), the parenchyma (for 36, 54, 72 seconds) and the aorta (for 18, 36, 54, 72 seconds). The decreases in the early phase obtained with a low dose of gadobutrol caused blunter time intensity curves. The difference in the quality scores of the readers for the angiographic images for the use of the two different doses was not statistically significant (p > 0.05). Conclusion: A lower dose of gadobutrol can be used for MR renal angiogra-phy, but for MR renography the normal dose should be used. agnetic resonance imaging (MRI) is widely used in the morphologic assessment of the renal parenchyma and excretory system. It is especially useful in evaluating renal masses, the prenatal genitourinary system, urinary obstructions or infections (1). The functional evaluation of kidneys has been of interest for many years (2 7). A very high percentage of the functional kidney studies concern renovascular diseases (RVDs). An RVD can be a cause of hypertension and 1 5% of patients with hypertension have a RVD (8, 9). Although rare, diagnosis is important because RVD is potentially curable. More than 50% of high-grade stenosis progress to occlusion within two years (10, 11). MR can demonstrate structural and functional changes and plays an important role in the diagnosis of RVD. Gadobutrol (Gadovist, Schering, Berlin, Germany) is a gadolinium-based paramag-netic contrast agent. It is freely filtered by the glomerulus without tubular secretion or re-absorption. The total plasma clearance of gadobutrol is very close to renal clearance, so glomerular filtration is the main pathway of elimination (12 14). The
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Radiographic features of a 15-year-old boy with Smith-McCort dysplasia are presented. Dyggve-Melchior-Clausen syndrome without mental retardation has clinical and radiographic findings similar to those of Smith-McCort dysplasia. Both of... more
Radiographic features of a 15-year-old boy with Smith-McCort dysplasia are presented. Dyggve-Melchior-Clausen syndrome without mental retardation has clinical and radiographic findings similar to those of Smith-McCort dysplasia. Both of these syndromes are rare autosomal recessive disorders affecting skeletal development. The radiographic appearance of generalized platyspondyly with double-humped end-plates, and the lace-like appearance of iliac crests are pathognomonic and distinctive of these syndromes. Diagnostic features of these diseases are compared with others like Morquio&amp;amp;amp;amp;amp;amp;amp;amp;#39;s disease and spondylometaphyseal dysplasia, which may have similar vertebral changes, and are discussed in the light of the literature.
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A characteristic sonographic appearance that suggests a bowel lesion either benign or malign has long been known.&amp;amp;amp;amp;amp;#x27;p2 This sonographic pat-tern consists of a strong echogenic center created by luminal contents... more
A characteristic sonographic appearance that suggests a bowel lesion either benign or malign has long been known.&amp;amp;amp;amp;amp;#x27;p2 This sonographic pat-tern consists of a strong echogenic center created by luminal contents that is surrounded by a son-olucent rim corresponding to the ...
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Research Interests: Cognitive Science, Animal Behavior, Depression, Treatment, Stress, and 21 moreSwimming, Serotonin, Brain, Mice, Animals, Male, Magnetic Resonance, Animal Model, SERTRALINE, Analysis of Variance, Time Factors, Forced Swim Test, Locomotor Activity, Long Term Effect, Nuclear Magnetic Resonance Imaging, Neurosciences, Drug treatment, Selective serotonin reuptake inhibitor, Motor activity, Magnetic resonance image, and desipramine
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Joubert syndrome is a rare disorder characterized by hypotonia, ataxia, episodic hyperpnoea, psychomotor delay, abnormal ocular movements, and molar tooth sign on magnetic resonance imaging (MRI). This syndrome is inherited as an... more
Joubert syndrome is a rare disorder characterized by hypotonia, ataxia, episodic hyperpnoea, psychomotor delay, abnormal ocular movements, and molar tooth sign on magnetic resonance imaging (MRI). This syndrome is inherited as an autosomal recessive trait, but the molecular basis and specific chromosomal locus have not yet been identified. MRI features are the most important diagnostic criteria. Molar tooth sign was previously described in Joubert syndrome and was found in 85% of patients with Joubert syndrome. Many authors now claim that this finding can be present in other syndromes, including Dekaban-Arima, Senior-Löken, COACH, and Varadi-Papp. We present a 7-month-old girl with Joubert syndrome in whom MRI showed the typical features of this condition. She also had polydactyly, atrial septal defect, and persistent left superior vena cava.
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The effect of electromagnetic shock waves on the ureter and periureteric soft tissue was investigated in 10 patients who underwent extracorporeal shock wave lithotripsy (ESWL) for lower ureteric stones. Seven patients were males and 3... more
The effect of electromagnetic shock waves on the ureter and periureteric soft tissue was investigated in 10 patients who underwent extracorporeal shock wave lithotripsy (ESWL) for lower ureteric stones. Seven patients were males and 3 females, their ages ranged between 15 and 52. The number of shock waves applied varied between 3000 and 6000, at a mean of 19 kV. The patients were examined after their first ESWL. Magnetic resonance imaging (MRI) was performed within 6 hours of treatment by a Magnetom 1 Tesla Unit. No haematoma, fluid collection or abnormality was detected in the periureteric space, muscle or surrounding structures by MRI. Although subcapsular, intra- or perirenal haematomas can be observed in patients with kidney stones treated with ESWL, it appears to be safe for lower ureteric stones.
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A 6-year-old boy with multiple sclerosis, youngest diagnosed in our hospital, is presented. In addition to the clinical findings, the diagnosis was supported by increased immunoglobulin levels, positive IgG index and oligoclonal bands in... more
A 6-year-old boy with multiple sclerosis, youngest diagnosed in our hospital, is presented. In addition to the clinical findings, the diagnosis was supported by increased immunoglobulin levels, positive IgG index and oligoclonal bands in the cerebrospinal fluid, normal cranial angiography, typical lesions on the cranial computed tomography and magnetic resonance imaging.
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Research Interests: Adolescent, Brain, Humans, Child, Female, and 5 moreMale, Infant, Lung, X ray Computed Tomography, and Child preschool
The close proximity of the prostate, vas deferens, seminal vesicles and ejaculatory ducts are a diagnostic challenge to the cysts located in that region. Three patients with diverticulum of the ejaculatory ducts, 2 with prostate cysts and... more
The close proximity of the prostate, vas deferens, seminal vesicles and ejaculatory ducts are a diagnostic challenge to the cysts located in that region. Three patients with diverticulum of the ejaculatory ducts, 2 with prostate cysts and 1 patient with seminal vesicle cyst are presented. Transrectal ultrasound, computed tomography and magnetic resonance imaging together with aspiration of the cyst establish diagnosis and probably prevent unnecessary exploration.
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We performed diffusion tensor imaging (DTI) and magnetic resonance spectroscopy (MRS) studies in a group of patients with subacute sclerosing panencephalitis (SSPE) in order to estimate the pathologic process underlying the phenotypic... more
We performed diffusion tensor imaging (DTI) and magnetic resonance spectroscopy (MRS) studies in a group of patients with subacute sclerosing panencephalitis (SSPE) in order to estimate the pathologic process underlying the phenotypic variability. Patients with SSPE who had MRI including DTI and MRS examinations were evaluated according to their clinical status as determined by the SSPE Scoring System and their mental age as determined by tests appropriate for age and developmental level. Comparisons of fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values and metabolite ratios of frontal periventricular white matter, parieto-occipital periventricular white matter, and globus pallidus in both hemispheres were made between control and SSPE groups, and between SSPE subgroups. Control (n = 18) and SSPE (n = 39) groups differed in all DTI and MRS parameters except FA, choline (Cho), and Cho/creatine (Cr). SSPE cases had higher ADC and lower N-acetylaspartate (NAA), NAA/Cho, and NAA/Cr in all regions of interest, suggesting cell loss. Disease progression rate and neurologic deficit appeared to be associated with the degree of ADC elevation and NAA reduction: the group with severe global deterioration had the lowest NAA (230.75 ± 197.97 in forceps minor), and rapid progression was associated with acute reduction in NAA. The combination of MRS and diffusion MRI findings suggests neuronal loss can be a primary target in rapidly or subacutely progressing SSPE, and preservation or regeneration of axonal structure may be beneficial in chronic cases.
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Research Interests: Magnetic Resonance Imaging, Adolescent, Muscle strength, Humans, Close relationships, and 15 moreFemale, Male, Pediatric Nephrology, Pediatric, Body Mass Index, Physical Performance, Peritoneal Dialysis, Chronic Kidney Failure, Physical Function, Exercise Test, Functional Testing, Isometric Contraction, Muscle mass, Physical Endurance, and Magnetic resonance image
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Intraventricular virtual MR endoscopic imaging of the foramen of Monro region by using three-dimensional Fourier transformation constructive interference in steady state (3DFT-CISS) magnetic resonance imaging in a patient with a... more
Intraventricular virtual MR endoscopic imaging of the foramen of Monro region by using three-dimensional Fourier transformation constructive interference in steady state (3DFT-CISS) magnetic resonance imaging in a patient with a unilateral congenital obstruction of the foramen of Monro by a transparent membranous septum was performed to enhance the orientation, achieve a better understanding of the pathology, and plan the surgical intervention in an endoscopic approach to the lateral ventricles. 3DFT-CISS sequences and virtual MR endoscopic imaging were performed in a patient before and after endoscopic fenestration procedures, to communicate the lateral ventricle to the third ventricle for the treatment of unilateral ventricular enlargement. Preoperative 3DFT-CISS imaging demonstrated unilateral membranous septa in the localization of the left foramen of Monro which were not observed with routine T2-weighted imaging. 3DFT-CISS imaging and T2-weighted imaging were equally useful for monitoring postoperative changes in the size of the ventricles or cysts and the presence of flow voids after fenestration procedures, but only 3DFT-CISS imaging clearly demonstrated the area of fenestration. Virtual MR endoscopy by using 3DFT-CISS sequences is a feasible method in the planning of intraventricular real-time endoscopic surgery, for the enhancement of orientation in a surgical field, and to achieve a better understanding of the pathology.
Research Interests: Magnetic Resonance Imaging, Treatment Outcome, Endoscopy, Hydrocephalus, Humans, and 12 moreMale, Three Dimensional Imaging, Clinical Sciences, Computer User Interface Design, Adult, Neuroendoscopy, Sensitivity and Specificity, Minimally Invasive, Ventriculostomy, Neurosciences, Predictive value of tests, and Functional Laterality
Research Interests: Magnetic Resonance Imaging, Humans, Cerebral Cortex, Female, Male, and 17 moreMagnetic Resonance, Neuronavigation, Clinical Sciences, Aged, Middle Aged, Adult, Three Dimensional, Reproducibility of Results, Volume Rendering, Minimally Invasive, Neurosciences, Predictive value of tests, Contrast Media, Brain Neoplasms, Scalp, Statistics as Topic, and Craniotomy
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We report a case of a supracondylar process that was located beneath the neurovascular bundle and caused tenting of the bundle with elbow extension and supination.
Research Interests: Pain, Humans, Female, Clinical Sciences, Elbow Joint, and 4 moreHumerus, Adult, PARESTHESIA, and Forearm
A characteristic sonographic appearance that suggests a bowel lesion either benign or malign has long been known.&amp;amp;amp;amp;amp;#x27;p2 This sonographic pat-tern consists of a strong echogenic center created by luminal contents... more
A characteristic sonographic appearance that suggests a bowel lesion either benign or malign has long been known.&amp;amp;amp;amp;amp;#x27;p2 This sonographic pat-tern consists of a strong echogenic center created by luminal contents that is surrounded by a son-olucent rim corresponding to the ...
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Ferhunde Oktem, PhD; Bari&amp;scedil; Diren, MD; Ergun Karaagaoglu, PhD; ... Received May 1, 2000. Received revised July 5, 2000. Accepted for publi- ... Karaagaoglu), and Child Neurology (Dr Anlar), Hacettepe University; and ...... more
Ferhunde Oktem, PhD; Bari&amp;scedil; Diren, MD; Ergun Karaagaoglu, PhD; ... Received May 1, 2000. Received revised July 5, 2000. Accepted for publi- ... Karaagaoglu), and Child Neurology (Dr Anlar), Hacettepe University; and ... Hacettepe University Faculty of Medicine, Ankara ...
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The greatest difficulty in the CT diagnosis of perforated pulmonary hydatid cyst (PPHC) is the increase in the attenuation numbers following infection. Because of the solid density of infected hydatid cysts, the differentiation from an... more
The greatest difficulty in the CT diagnosis of perforated pulmonary hydatid cyst (PPHC) is the increase in the attenuation numbers following infection. Because of the solid density of infected hydatid cysts, the differentiation from an abscess or neoplasm is usually impossible. The aim of this study was to evaluate the value of &quot;air bubble&quot; as a new CT sign in the diagnosis of PPHC. Sixty-five patients (28 men and 37 women) with PPHC were included in the study. As a control group, 55 patients who had malignant (n = 36) or non-malignant (n = 19) pulmonary diseases were also examined. Radiological diagnosis with classical CT findings was made in only 38 of 65 patients (58.5 %) with PPHC. Air bubble sign was positive in 54 of the patients with PPHC (sensitivity 83.1 %) but only 3 of 55 patients in control group (specificity 94.5 %). When we analyzed the CT scans with classical CT findings including air bubble, the diagnosis of PPHC was made in 61 of patients (93.8 %). It is concluded that &quot;air bubble sign&quot; is a valuable CT finding in the diagnosis of PPHC.