Page 9 - Best diagnosticians: TOP 413 doctors

Dr. Tolga Sinan Guvenc is a cardiologist at Memorial Göztepe Hospital (2025–). He previously worked at VM Medical Park Pendik (2019–2025) and at Dr. Siyami Ersek Thoracic and Cardiovascular Surgery Training and Research Hospital (2014–2018).

He has authored over 200 scientific articles and book chapters. He serves on the Editorial Board of Scientific Reports.

He is a Fellow of the ESC Heart Failure Association. He is also a member of the Turkish Society of Cardiology, the European Society of Cardiology, and Sigma Xi.

Advanced training includes a clinical fellowship in the Advanced Heart Failure Unit at the University of Alberta. He also served as a visiting scientist at the Echocardiography Station at the University of Alabama at Birmingham. Education: MD, Istanbul University Cerrahpaşa (English). Cardiology residency, Dr. Siyami Ersek.

Dr. Ahmet Mutlu is an ENT specialist at Memorial Göztepe Hospital (2025–present). He holds European Board certification in ORL‑HNS (FEBORL‑HNS, 2018) and National ENT Board certification (2016). Education: MD, Kocaeli University (2011). ENT residency, Kocaeli University (2011–2016). Master’s in Audiology, Başkent University (2017).

Previous posts: Istanbul Medeniyet University (2019–2025). Üsküdar State Hospital (2016–2019). Kocaeli University (2011–2016). Training: Otology‑Neurotology School (2019–2020). Laryngology & Phoniatrics School (2021–2022). Portmann Institute microsurgery course (2013). Memberships: Turkish ORL‑HNS, Istanbul ENT Assoc., Otology‑Neurotology, Phoniatrics, Turkish Medical Association.

Professor, specialist of ophthalmology

Dr. Mehmet Semih is a cardiology specialist at Memorial Göztepe Hospital (2025–present). He previously served as a specialist at Koşuyolu High Specialty Training and Research Hospital (2024–2025) and Sivas Numune Hospital (2023–2024). He completed his cardiology residency at Istanbul University Cerrahpaşa (2018–2023). He earned his MD at Istanbul University (2006–2012).

He is a member of the Turkish Society of Cardiology, the European Society of Cardiology, and the European Heart Rhythm Association. He has delivered oral case presentations at EHRA and TKD congresses. He also completed the TKD Bifurcation Lesions Management Course and the TKD Echocardiography Symposium.

Dr. Sabahattin Gunduz is a cardiologist at Memorial Göztepe Hospital (2025–present). He previously worked as a cardiology specialist at VM Medical Park Pendik Hospital (2018–2025). He also served at Kartal Koşuyolu Heart Hospital (2014–2018), Tuzla State Hospital (2012–2014), and Ümraniye Training and Research Hospital (2010–2012).

He is a Professor of Cardiology at Bahçeşehir University, Faculty of Medicine (2022). He became an Associate Professor at Istanbul Kartal Koşuyolu High Specialty Training and Research Hospital (2017). He completed his cardiology residency at the same institution (2005–2009). He earned his MD from Istanbul University (1999–2005).

Professional memberships: TTB, TKD, ESC, EAPCI, EACVI.

Dr. Bulen Can is an endocrinology specialist at Memorial Göztepe Hospital (2025–present). He previously worked at Acıbadem Ataşehir (2024–2025). From 2017 to 2024, he was a faculty member in the Division of Endocrinology at Istanbul Medeniyet University. He also practiced at Ankara Numune, Kastamonu Dr. M. İslamoğlu, and Ümraniye Training and Research Hospitals. He has been an endocrinology specialist since 2013.

He completed subspecialty training in Endocrinology and Metabolic Diseases at Istanbul University, Istanbul Faculty of Medicine (2009–2013). Before that, he finished his Internal Medicine residency at Bezm‑i Âlem Vakıf Gureba (2003–2009). He received his M.D. from the Istanbul Faculty of Medicine. He is a member of TEMD, TİHUD, TTB, and the Istanbul Medical Chamber. He attended the 46th TEMD Congress (2025), Aydın Endocrine Days (2022), and Clinical Research Training (2017).

Dr. Ozgur Kilickesmez is an interventional neuroradiology and interventional radiology specialist at Memorial Goztepe Hospital in Istanbul (2025–present). He previously worked at Medicana Atakoy and Zincirlikuyu (2024–2025). He also served at Basaksehir Cam ve Sakura City Hospital (2020–2024), Istanbul Training and Research Hospital (2012–2020), and Guy’s and St Thomas’ Hospital in London (2011–2012).

He is a Professor at the University of Health Sciences (2020). He was an Associate Professor at Yeditepe University Hospital (2010). He completed training in interventional oncology at King’s College University (2011) and in interventional radiology at Cerrahpasa (2010). He provides international training in minimally invasive tumor therapy, non-surgical thyroid interventions, new-generation embolization, and stent-based brain aneurysm treatment. He is a member of RSNA, ESR, CIRSE, and ESNR. He also belongs to Turkish radiology, neuroradiology, interventional radiology, and oncology societies.

Dr. Muslim Sahin is a cardiology specialist at Memorial Göztepe Hospital (2025–present). He previously worked at VM Medical Park Pendik Hospital (2018–2025), Kartal Koşuyolu High Specialty Training and Research Hospital (2010–2018), Kartal Yavuz Selim State Hospital (2007–2010), and Kayseri Military Hospital (2006–2007).

He completed his cardiology residency at Maltepe University Faculty of Medicine (2001–2005). He earned his MD from Istanbul University Cerrahpaşa Faculty of Medicine (1995–2001).

He is a member of the Turkish Medical Chamber, the Turkish Society of Cardiology, the EuroCTO Club, and the European Society of Cardiology. He has completed training in TAVI, MitraClip, and renal denervation.

Dr. Vafa Guliyeva is a pediatric rheumatologist at Memorial Göztepe Hospital in Istanbul. She previously worked at Memorial Şişli and LIV Bona Dea. Before that, she was a pediatrics specialist at Florence Nightingale Hospital.

Training: Pediatric rheumatology subspecialty at Istanbul University and Istanbul Cerrahpaşa University. Pediatrics residency at Istanbul Medeniyet University.

Achievements: Author of 20 international and 3 national peer-reviewed articles. Presented 3 international and 20 national conference papers. Contributed to 4 book chapters. Principal investigator of a BAP scientific project.

Memberships: Turkish Medical Association (TTB). Pediatric Rheumatology Association. Paediatric Rheumatology European Society (PReS).

Dr. Deniz Goren is a specialist in internal medicine and hematology at Memorial Göztepe Hospital (Istanbul). Dr. Goren previously worked at Memorial Şişli, Istanbul Florence Nightingale, and Eskişehir Yunus Emre State hospitals.

Dr. Goren served as an associate professor at Demiroglu Bilim University from 2020 to 2024 and earlier as an assistant professor from 2017 to 2020. Dr. Goren completed a hematology subspecialty at Eskişehir Osmangazi University. Dr. Goren completed an internal medicine residency and earned an MD at Ankara University. Dr. Goren later completed a postdoctoral fellowship at Harvard Medical School and the Joslin Diabetes Center.

Awards include TÜBİTAK 2219, the Turkish Hematology Association Young Participant and Fuat Aydınlı Young Researcher awards, and the SOHO Young Investigator Grant. Dr. Goren has published 32 international and 14 national peer‑reviewed articles and delivered 88 presentations. Dr. Goren completed the EBMT International Transplant Course, the Lymphoma Master Class, and the Advanced Life Support Course.

Dr. Mahir Cengiz is a Professor of Internal Medicine and an Internal Medicine Specialist. He works at Memorial Göztepe Hospital (2025–present). He previously served at Istanbul Aydın University–Medical Park Florya (2022–2025). He held roles at Biruni University Hospital as Lecturer and Chief Physician (2018–2022). Earlier, he was a Lecturer at Istanbul University–Cerrahpaşa Faculty of Medicine (2013–2018) and Chief Physician at Şarkışla State Hospital (2012–2013).

His track record includes 12 years as a lecturer and 5 years as a chief physician. He earned his MD from Istanbul University, Istanbul Faculty of Medicine (2000–2006). He completed an Internal Medicine residency at Istanbul University–Cerrahpaşa (2006–2011). He served as Chief Resident in Internal Medicine (2013–2017). He became an Associate Professor in 2017 and a Professor in 2022.

Dr. Fatih Gumus is a Cardiovascular Surgery Specialist at Memorial Göztepe Hospital (2025–present). He previously served at Memorial Ankara (2023–2025) and Bartın State Hospital (2018–2022). He completed his Cardiovascular Surgery residency at Ankara University (2013–2018). He was a Clinical Fellow at Johns Hopkins University in 2010. He observed Vascular Surgery at the Cleveland Clinic in 2014. He earned his MD from Hacettepe University (English program, 2005–2012).

He has authored five peer-reviewed papers on minimally invasive valve surgery, right heart and LVAD assessment, and DVT therapy. He is a member of EACTS, ISMICS, MIRC, the Turkish Society of Cardiovascular Surgery, and the Turkish Society of Vascular Surgery. He served as faculty at the 19th ICCVS. He gave oral talks at EACTS 2017, ISMICS 2018, and UIP 19th.

Dr. Ahmet Ekmekci is a cardiology specialist at Memorial Göztepe Hospital in Istanbul, since 2025. He earned the title of Associate Professor of Cardiology (Doçent) in 2014.

He served as Chief Assistant in Cardiology at Dr. Siyami Ersek Training and Research Hospital in 2010. He completed his cardiology residency at the same hospital in 2009. He finished his internal medicine residency at the Istanbul Faculty of Medicine from 2002 to 2007. He received his MD from Istanbul University, Istanbul Faculty of Medicine, in 2002.

He is a member of the Turkish Society of Cardiology, the European Society of Cardiology, and the European Heart Failure Association (Gold Member). He is also a member of the Istanbul Internal Medicine Association, the Stem Cell and Cellular Therapies Association, the Istanbul Medical Chamber, and the Turkish Medical Association. He served on the Board of the Turkish Society of Cardiology Heart Failure Working Group in 2016.

Dr. Hidayet Demir is a Cardiovascular Surgery Specialist at Memorial Göztepe Hospital (2025–). He previously served as an Assistant Professor at Okan University Hospital (2021–2025). He was also a specialist at Ağrı I. Ç. University Training and Research Hospital (2019–2021). Earlier, he worked at City Health Group as Medical Director and ECMO Specialist (2015–2018). He later served as CEO (2018–2025).

Education: MD, Istanbul University Cerrahpaşa (2007–2013). Cardiovascular Surgery residency, SBÜ Kartal Koşuyolu (2013–2019). Beating‑Heart Coronary Bypass observer, Royal Brompton & Harefield Hospital (2018).

Memberships: TKDCD, UVECD, Turkish Medical Association, ESVS, EACTS. Courses: MIRC 2017 (minimally invasive/robotic). UVECD & EVC 2017 Venous Workshop. European Vascular Course 2017: Open Abdominal Aortic Aneurysm Treatment. TKDCD advanced aortic surgery. ESVS aortic arch techniques.

Dr. Haluk Caglar Karakaya is a specialist in cardiovascular surgery at Memorial Göztepe Hospital in Istanbul (2025–). He previously worked as a specialist at the University of Health Sciences Sancaktepe Şehit Prof. Dr. İlhan Varank Training and Research Hospital (2022–2025). He completed residency training at the University of Health Sciences Dr. Siyami Ersek Thoracic and Cardiovascular Surgery Training and Research Hospital and at Ankara University. He earned his MD from Hacettepe University (English program).

Professional memberships: European Society for Cardiothoracic Surgery (EACTS), European Society for Vascular Surgery (ESVS), Turkish Society of Cardiovascular Surgery, National Society of Vascular and Endovascular Surgery.

Continuing education: 27th European Vascular Course (2024); Cardiac Memorial Robotic/Minimally Invasive Cardiac Surgery Summit (2024); 18th Turkish Cardiovascular Surgery Congress (2024); 24th ASVS Congress (2023); TKDCD Endovascular Course (2023); “Grey Areas in Vascular Surgery” Symposium (2023); Basic and Advanced Doppler Ultrasonography Course (2023).

Dr. Berrak Beyoglu Oruc is a specialist in obstetrics, gynecology, and IVF at Memorial Göztepe Hospital (2025–). She previously worked at Bahçeşehir University Medical Park Göztepe Hospital and Ağrı Training and Research Hospital. She also served as a research physician in gynecologic oncology at Bologna University S. Orsola (2022).

Accreditations and key training include: Certified ART Clinical Training, American Hospital (2025); GESEA MIGS Level 1 – European Certified Minimal Invasive Gynaecological Surgeon (2024). She also completed the Harvard Women’s Health and Menopause Course (2025), ESGO ORSI Robotic Surgery (2022), ESGO Masterclass (2022), and TMFTP Second Trimester Ultrasound (2024).

Awards: First prize, oral presentation—Transperineal Ultrasonography in Predicting Operative Delivery (13th Maternal–Fetal Medicine and Perinatology Congress, 2023). Third prize—Aortic Dissections (2016). Memberships: ISUOG, ESGE, MIJID, TJOD.

Dr. Isik Okuyan is an obstetrics and gynecology specialist at Memorial Göztepe Hospital in Istanbul (2025–present). He previously worked at Şanlıurfa Training and Research Hospital (2023–2025). He completed his OB/GYN residency at SB University Istanbul Training and Research Hospital (2019–2023). He earned his MD from Mersin University (2011–2017).

His credentials include GESEA Level 1 in Gynecological Endoscopy (Marseille, 2024). He presented a video and a poster at the 33rd ESGE Congress (2024). He is a member of the Turkish Medical Association, the Turkish Society of Gynecology and Obstetrics, and ESGE. He took part in meetings from 2022 to 2025, including ISON and national gynecology congresses.

Dr. Basak Sargin is an obstetrics and gynecology (OB/GYN) specialist at Memorial Göztepe Hospital. She has worked at Medipol Mega University Hospital (IVF and Reproductive Health Center), Medipol Acıbadem Region, Memorial Ataşehir Hospital, and Kars Harakani State Hospital.

Accreditations: FMAS and DMAS, World Laparoscopy Hospital (2023). ART training, American Hospital (07/2024–01/2025). Fellowships: Minimally Invasive and Advanced Gynecologic Surgery, Pius University, Oldenburg (07/2025); World Laparoscopy Hospital (05/2023). Additional training in robotic surgery, hysteroscopy, vNOTES, embryo transfer simulation, and laser/magnetic stimulation.

Education: MD, Hacettepe University. OB/GYN residency, Ankara (2016–2021). PhD candidate in Biomedical Engineering, Koç University (since 2023). Memberships: SRGS, International Society of Gynecology and Obstetrics, ESGE, WALS, and Istanbul Medical Chamber.

Dr. Aygul Aliyeva Onen is a specialist in obstetrics and gynecology at Memorial Göztepe Hospital (2025–present). She previously worked at Medical Park Göztepe (2023–2025) and at Celal Bayar University Hafsa Sultan Hospital (2018–2023). She completed her obstetrics and gynecology residency at Celal Bayar University Faculty of Medicine (2018–2023). She graduated from Azerbaijan Medical University (2010–2016) and completed an observership at Ege University (2017).

Professional memberships include the Istanbul Medical Chamber, the Turkish Society of Gynecology and Obstetrics, and the Pelvic Floor and Cosmetic Gynecology Association. Additional training includes Current Approaches in Cosmetic Gynecology (TJOD Izmir); CCI HADYEK Laparoscopic Gynecologic Surgery; Sexual Health Federation—Vaginismus and Dyspareunia; the 1st–3rd International Pelvic Floor and Cosmetic Gynecology Congresses; and the TJOD Obstetric Simulation Course.