Orhan Coskun

Dr. Orhan Coskun


Research Focus & Metrics

Academic Career Length

12Years (2015-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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15 February 2020 in Turkish Journal of Gastroenterology
Verified
Journal Article
Closed access
VGVolkan Gökbulut
Volkan Gökbulut
MKMustafa Kaplan
Mustafa Kaplan
SKSabite Kaçar
Sabite Kaçar
MKMeral Akdoğan Kayhan
Meral Akdoğan Kayhan
OCOrhan Coskun
Orhan Coskun
EKErtuğrul Kayaçetin
Ertuğrul Kayaçetin
Background/Aims: We aimed to investigate the association of bezoar with endoscopic findings, risk factors for bezoar occurrence, and the success of endoscopic treatment in a tertiary center. Materials and Methods: This retrospective study was conducted between January 2012 and December 2015. Overall, 8200 endoscopy records were examined and 66 patients with bezoar were included in the study. Results: We enrolled 29 (44%) female and 37 (56%) male patients in this study. The mean age of the patients was 63±9.4 years. The most frequent risk factors were history of gastrointestinal surgery (23%), diabetes mellitus (17%), trichophagia (9%), and anxiety disorder (6%). Gastric ulcer, duodenal ulcer, erosive gastritis, and reflux esophagitis were present in 27%, 11%, 20%, and 23% of the patients, respectively. While bezoars were most commonly observed in the stomach (70%), the majority of them were phytobezoars (91%). The mean number of interventions for each patient was 1.5 (range, 1-6). Endoscopy was successful in removing bezoars in 86.5% of the patients. Among those referred to surgery, seven patients underwent gastrostomy (10.5%); one (1.5%) patient underwent gastroenterostomy because of concomitant pyloric stenosis; and one (1.5%) patient underwent fistula repair surgery due to the development of duodenal fistula caused by bezoar. Conclusion: The findings of this study indicated that bezoars are more common among subjects with history of gastrointestinal surgery, diabetes mellitus, or psychiatric disorders; bezoars are closely related to peptic ulcer and reflux esophagitis; and they can be successfully treated with endoscopy.

Verified
Journal Article
Open access
PDF file
OOOguz Ozturk
Oguz Ozturk
MEMucahit Ergul
Mucahit Ergul
YCYavuz Cagir
Yavuz Cagir
AAAli Atay
Ali Atay
KAKadir Can Acun
Kadir Can Acun
IYIlhami Yuksel
Ilhami Yuksel
Background/Objectives: Chat Generative Pretrained Transformer (ChatGPT) is a useful resource for individuals working in the healthcare field. This paper will include descriptions of several ways in which ChatGPT-4 can achieve greater accuracy in its diagnosis and treatment plans for ulcerative colitis (UC) and Crohn’s disease (CD) by following the guidelines set out by the European Crohn’s and Colitis Organization (ECCO). Methods: The survey, which comprised 102 questions, was developed to assess the precision and consistency of respondents’ responses regarding the UC and CD. The questionnaire incorporated true/false and multiple-choice questions, with the objective of simulating real-life scenarios and adhering to the ECCO guidelines. We employed Likert scales to assess the responses. The inquiries were put to ChatGPT-4 on the initial day, the 15th day, and the 180th day. Results: The 51 true or false items demonstrated stability over a six-month period, with an initial accuracy of 92.8% at baseline, 92.8% on the 15th day, and peaked to 98.0% on the 180th day. This finding suggests a negligible effect size. The accuracy of the multiple-choice questions was initially 90.2% on Day 1, reached its highest point at 92.2% on Day 15, and then decreased to 84.3% on Day 180. However, the reliability of the data was found to be suboptimal, and the impact was deemed negligible. A modest, transient increase in performance was observed at 15 days, which subsequently diminished by 180 days, resulting in negligible effect sizes. Conclusions: ChatGPT-4 demonstrates potential as a clinical decision support system for UC and CD, but its assessment is marked by temporal variability and the inconsistent execution of various tasks. Essential initiatives that should be carried out before involving artificial intelligence (AI) technology in IBD trials are routine revalidation, multi-rater comparisons, prompt standardization, and the cultivation of a comprehensive understanding of the model’s limitations.

13 February 2023 in Turkish Journal of Gastroenterology
Verified
Journal Article
Open access
ITIlyas Tenlik
Ilyas Tenlik
ÖÖÖMER ÖZTÜRK
ÖMER ÖZTÜRK
YÖYasemin Özin
Yasemin Özin
DADerya Arı
Derya Arı
OCOrhan Coskun
Orhan Coskun
ZKZeki Mesut Yalın Kılıç
Zeki Mesut Yalın Kılıç
Background: The aim of the study was to share the effectiveness of pneumatic dilation in geriatric achalasia patients. Methods: Achalasia patients over the age of 65 and those under the age of 65 as the control group who received pneumatic dilation as the first-line treatment were evaluated in the study. Results: The average age of geriatric patients was 72.5 ± 55.92 years (65-90), with 50.3% of them being male. Follow-up was conducted for a mean of 64.52 ± 38.73 months. While pneumatic dilation was successful in 98.6% (141/143) of geriatric patients, it was also successful in 94% (141/150) of non-geriatric patients. Remission after single balloon dilatation was observed in 81.8% of geriatric patients, while it was observed in only 52.7% of non-geriatric patients (P = .000). When comparing remission after single dilatation and multiple dilatations, it was observed that geriatric patients who achieved remission after multiple balloon dilatation had higher lower esophageal sphincter pressure and Eckardt scores at the diagnosis and higher lower esophageal sphincter pressure and esophageal body resting pressures after the first balloon dilatation. Conclusions: The proportion of elders in the world population is increasing daily and this disease has been known to disproportionately afflict this group. Although surgical treatments, in particular per-oral endoscopic myotomy, have recently gained popularity as therapies for achalasia, pneumatic dilation remains the most commonly used in geriatric patients. Cite this article as: Tenlik İ, Öztürk Ö, Özin Y, et al. Pneumatic dilation in geriatric achalasia patients. Turk J Gastroenterol. 2023;34(4):332-338.

15 April 2023 in Scientific Reports
Verified
Journal Article
Open access
PDF file
ÇEÇağdaş Erdoğan
Çağdaş Erdoğan
DADerya Arı
Derya Arı
BYBayram Yeşil
Bayram Yeşil
KKKenan Koşar
Kenan Koşar
OCOrhan Coskun
Orhan Coskun
MYMahmut Yüksel
Mahmut Yüksel
Non-gastric upper gastrointestinal system polyps are detected rarely and mostly incidentally during upper gastrointestinal endoscopy. While the majority of lesions are asymptomatic and benign, some lesions have the potential to become malignant, and may be associated with other malignancies. Between May 2010 and June 2022, a total of 127,493 patients who underwent upper gastrointestinal endoscopy were retrospectively screened. Among these patients, those who had polyps in the esophagus and duodenum and biopsied were included in the study. A total of 248 patients with non-gastric polyps were included in this study. The esophageal polyp detection rate was 80.00/100,000, while the duodenal polyp detection rate was 114.52/100,000. In 102 patients (41.1%) with esophageal polyps, the mean age was 50.6 ± 15.1, and 44.1% (n = 45) were male. The most common type of polyps was squamous papilloma (n = 61, 59.8%), followed by inflammatory papilloma (n = 18, 17.6%). In 146 patients (58.9%) with duodenal polyps, the mean age of patients was 58.3 ± 16.5, and 69.8% (n = 102) were male. Brunner's gland hyperplasia, inflammatory polyp, ectopic gastric mucosa, and adenomatous polyp were reported to be the most prevalent types of polyps in the duodenum overall (28.1%, 27.4%, 14.4%, and 13.7%, respectively). It is crucial to identify rare non-gastric polyps and create an effective follow-up and treatment plan in the era of frequently performed upper gastrointestinal endoscopies. The epidemiological assessment of non-gastric polyps, as well as a follow-up and treatment strategy, are presented in this study.

23 June 2025 in Turkish Journal of Gastroenterology
Verified
Journal Article
Open access
MDMuhammed Bahaddin Durak
Muhammed Bahaddin Durak
YCYasir Furkan Cagin
Yasir Furkan Cagin
ABAyhan Balkan
Ayhan Balkan
YCYusuf Coşkun
Yusuf Coşkun
TKTarkan Karakan
Tarkan Karakan
IYIlhami Yuksel
Ilhami Yuksel
Background/Aims: Inflammatory bowel diseases (IBDs) are increasingly prevalent and challenging globally. Data regarding IBD frequency and severity between Europe and Asia are needed. The aim was to investigate the trend of IBD in Türkiye during the last 3 decades. Materials and Methods: The study was conducted retrospectively at 14 centers in Türkiye between June 1993 and March 2024. Results: Over 30 years, 4308 patients, of whom 2507 (58.2%) had ulcerative colitis (UC) and 1717 (39.9%) had Crohn’s Disease (CD), were included in the study. The overall median age at the onset of IBD was 34.43 (25.28-45.64) years; the age at onset of IBD was younger in CD compared to UC (32.72 vs. 35.52 years respectively, P < .001). The peak age onset range was 28-32 years in CD, whereas 23-27 years in UC. Overall, 2526 (58.6%) patients were male. The most common location was left-sided colitis in UC patients (45.1%), followed by extensive colitis (31.2%), and proctitis (23.7%), while ileal involvement in CD patients (45.2%), afterward ileocolonic (409%), and colonic (13.5%). Both illnesses are becoming increasingly prevalent. The UC/CD ratio tends to decrease over time. During the study period, 1577 (36.6%) patients received biologic treatment. During the study period, 418 (24.3%) underwent resective surgery for CD and 88 (3.5%) total colectomy for UC; the major abdominal surgery has declined over time. Conclusion: The frequency and characteristic features of IBD in Türkiye appear to be between Europe and Asia. Over time, while the usage of biologic therapy and the rate of CD have increased, the frequency of surgery has decreased. Cite this article as: Durak MB, Cagin YF, Balkan A, et al. Three-decade analysis of inflammatory bowel disease in Türkiye: A multicenter study (1993-2024). Turk J Gastroenterol. 2025;36(12):822-833.

25 December 2019 in Endoskopi Gastrointestinal
Verified
Journal Article
Closed access
OCOrhan Coskun
Orhan Coskun
Giriş ve Amaç: Perkütan endoskopik gastrostomi uzun süreli enteral nütrisyona gereksinim duyan hastalarda beslenme için tercih edilen yöntemdir. Bu çalışmada perkütan endoskopik gastrostomi uygulanan hastalarımızdaki kısa ve uzun dönem sonuçlarımızı araştırdık. Gereç ve Yöntem: Bu çalışma Haziran 2017-Mayıs 2019 tarihleri arasında hastanemiz endoskopi ünitesinde perkütan endoskopik gastrostomi uygulanan hastalar ile yapıldı. Hastaların perkütan endoskopik gastrostomi endikasyonları, işlem detayları, takip süreleri ve gelişen komplikasyonlar retrospektif olarak hasta dosyalarından kaydedildi. Bulgular: Çalışmaya dahil edilen 58 hastanın 34’ü (%58.6) erkek, 24’ü ise (%41.4) kadındı. Hastaların ortalama yaşları 68.4 yıl idi (18-94). Üç hasta dışındaki 55 hastaya perkütan endoskopik gastrostomi başarıyla uygulandı (%94.8). En sık perkütan endoskopik gastrostomi yerleştirme endikasyonu nörolojik hastalıklardı (%84.4). Diğer endikasyonlar ise multitravma, malignite ve septisemiydi. Larenks kanseri nedeniyle total larenjektomili bir hastada özofagus darlığı nedeniyle balon dilatasyonu yapıldıktan sonra perkütan endoskopik gastrostomi yerleştirildi. Perkütan endoskopik gastrostomi prosedürüne bağlı olarak 4 hastada minör komplikasyonlar gözlendi (%7.3). Mortalite dahil hiçbir hastada majör komplikasyon görülmedi. Perkütan endoskopik gastrostomi prosedürü sonrası bir aylık dönem içinde 5 hastada (%8.6), bir aydan uzun dönemde ise 27 hastada diğer sebeplere bağlı mortalite gelişti (%46.6). Ölen 32 hastanın ortalama takip süresi 82 gün iken (4-355) kalan 23 hastanın ortalama takip süresi ise 279 gün idi (18-657). Sonuç: Perkütan endoskopik gastrostomi; beslenme desteğinin enteral olarak sağlanmasında güvenli, gereğinde yatak başında kolayca uygulanabilen, minimal invaziv, iyi tolere edilen ve düşük komplikasyon oranına sahip bir uygulamadır.