Best Doctors in the World

Dr. Yasar Colak is a Professor of Gastroenterology at Memorial Şişli Hospital in Istanbul. He has deep expertise in liver transplantation and therapeutic endoscopy. Dr. Colak served as an invited lecturer at the Cleveland Clinic Florida. He also worked in the Presidential Health Coordinatorate in Turkey.

• Specializes in liver transplantation and digestive tract disorders.
• Completed clinical training at the Cleveland Clinic Department of Endoscopic Applications.
• Treats patients at Memorial Şişli, the first JCI-accredited hospital in Turkey.
• Formerly served as an Associate Professor at Istanbul Civilization University.

Dr. Abdullah Yakupoglu is an interventional radiologist at Memorial Şişli Hospital in Istanbul. He specializes in interventional oncology. Dr. Yakupoglu has held several leadership roles at major Turkish medical centers. He works at a JCI-accredited facility known for its high success rates in complex procedures.

• Served as the Interventional Radiology Manager at Acıbadem Health Group.
• Former Interventional Radiology Manager at both American Hospital and German Hospital.
• Focuses on minimally invasive techniques for treating oncological conditions.
• Practices at the first Turkish hospital to earn Joint Commission International accreditation.

Dr. Bingur Sonmez is the Head of Cardiovascular Surgery at Memorial Şişli Hospital. He specializes in heart surgery and minimally invasive techniques. Dr. Sonmez completed his cardiac surgical training at Istanbul University. He later served as Chief Resident of Cardiovascular Surgery at St. Thomas Hospital in London.

• Leads the cardiac surgery department at a JCI-accredited medical center.
• Former Head of Surgical Sciences at Florence Nightingale Hospital.
• Treats patients at a facility with a 90% organ transplant success rate.
• Completed major international residency training in the United Kingdom.

Dr. Yunus Nas, MD, is an Assistant Professor, Pediatrician, and Infectious Diseases Specialist. He earned his medical degree at 19 Mayıs University Faculty of Medicine and completed his Infectious Diseases training there. He then completed a second specialization in Pediatrics at Zeynep Kamil Gynecology and Pediatrics Training and Research Hospital in Istanbul.

His practice focuses on pediatric infections and respiratory diseases. He treats childhood infections, chronic or recurrent cough, bronchitis, and bronchiolitis. He also manages tuberculosis and allergic diseases. He has experience in neonatal intensive care and pediatric emergency care. He provides preventive care and monitors growth and nutrition.

Dr. Engin Tutar is a pediatric gastroenterologist at Hisar Hospital Intercontinental in Istanbul. He is the former head of Pediatric Gastroenterology at Marmara University. Dr. Tutar has delivered over 50 presentations at national and international medical congresses. He specializes in treating complex digestive, liver, and nutritional disorders in children.

• Performs diagnostic and therapeutic endoscopy, including polypectomy and esophageal variceal bleeding control.
• Treats inflammatory bowel disease, Celiac disease, and H. pylori infections.
• Manages chronic pediatric conditions such as growth disorders and liver diseases.
• Works at JCI-accredited Hisar Hospital, which treats over 500,000 patients annually.

Dr. Onur Telli is a urologist and pediatric specialist at Memorial Şişli Hospital. He focuses on diagnosing and treating congenital urogenital anomalies. He has received awards from the European Association of Urology and the European Society for Pediatric Urology. Dr. Telli works at a JCI-accredited facility in Istanbul.

• Published over 50 international articles and contributed to three pediatric urology books.
• Conducted population-based research on nocturia in women of reproductive age.
• Member of the American Academy of Pediatrics Section on Urology.
• Member of the Turkish Association of Pediatric Urology.

The doctor is an Associate Professor with extensive clinical training and academic experience. Medical education was completed at Gazi University Faculty of Medicine, followed by specialized training as an Assistant Physician at Şişli Hamidiye Etfal Education and Research Hospital. Further expertise was gained through minor specialization training at the T.R. Istanbul Science University European Florence Nightingale Hospital.

With a career spanning over two decades, the doctor has demonstrated a commitment to medical excellence and academic advancement in the field, currently serving in a senior clinical and educational capacity in Istanbul.

Dr. Nesrin Sariman is a pulmonology and sleep medicine specialist at Hisar Hospital Intercontinental. She treats asthma, COPD, and lung cancer. Dr. Sariman is a bronchoscopy specialist. She participated in a multicenter international clinical study on asthma. Dr. Sariman holds certifications in functional medicine and phytotherapy from Medipol University.

• Served as Assistant Dean at Maltepe University from 2019 to 2022.
• Treats sleep disorders including obstructive sleep apnea syndrome.
• Maintains memberships in several national and international medical associations.
• Works at Hisar Hospital Intercontinental, a JCI-accredited facility in Istanbul.

The doctor has a background in Nutrition and Dietetics, having completed a bachelor's degree from Gumushane University. They have professional experience working in various health and wellness centers, including Diettherapy Nutrition and Diet Counseling Center, Mestetik Aesthetics and Beauty Center, and Estetica Beauty and Aesthetic Center. Additionally, the doctor has contributed to fitness and dietary services at Academy Fitness and Zafiran Restaurant, focusing on diet therapy and nutritional counseling.

Dr. Burak Akbay is an ophthalmologist at Memorial Bahçelievler Hospital in Istanbul. He has performed over 1,500 oculoplastic cases. Dr. Akbay is a Fellow of the European Board of Ophthalmology (FEBO). He treats patients at a JCI-accredited medical center. This accreditation is a global gold standard for patient safety.

• Holds FEBO certification, a high mark of European professional quality.
• Completed residency training in ophthalmology at Pamukkale University.
• Active member of the Turkish Ophthalmological Society.
• Specializes in complex eye and eyelid surgery.

The doctor is a graduate of one of the premier dental schools in Istanbul. With a dedicated focus on restorative and aesthetic dentistry, the doctor is committed to providing high-quality dental care and improving patient smiles through professional clinical practice.

Dr. Fazilet Karakoc is a pediatric pulmonologist at Memorial Şişli and Memorial Ataşehir hospitals in Istanbul. She serves as a member of the Department of Pediatric Chest Diseases at Marmara University. Dr. Karakoc specializes in treating children with complex respiratory and lung conditions. She works at JCI-accredited Memorial Şişli, the first hospital in Turkey to earn this safety standard.

• Serves as both a pediatric chest specialist and a general pediatric health specialist.
• Maintains an academic role at the Marmara University Faculty of Medicine.
• Treats patients at one of Turkey’s leading multidisciplinary medical centers.
• Focuses on pediatric pulmonology within a hospital network serving 160+ countries.

Prof. Dr. Gülden Kafalı is a Professor of Pediatric Cardiology. She diagnoses and treats heart diseases in children and adolescents, including congenital heart disease, cardiac arrhythmias, cardiomyopathies, myocarditis, and acute rheumatic fever. Her skills include fetal echocardiography and heart screening for young athletes.

She earned her M.D. from Ege University Faculty of Medicine (1978–1984). She completed a Pediatrics residency at Cumhuriyet University Faculty of Medicine (1988–1992). She finished a Pediatric Cardiology subspecialty at Hacettepe University Faculty of Medicine (1999–2002).

She has worked at Kartal Koşuyolu High Specialization Training and Research Hospital, Istanbul Bilim University Faculty of Medicine, Trakya University Faculty of Medicine, and Ataşehir Florence Nightingale Hospital. She provides pediatric cardiac evaluation and follow-up care.

Dr. Fatma Kural Aydin is an internal medicine specialist at Hisar Hospital Intercontinental in Istanbul. She focuses on endocrine and metabolic diseases. Dr. Aydin graduated from the Istanbul University Cerrahpaşa School of Medicine. She later finished her residency at the Istanbul School of Medicine.

• Expert in managing complex internal medical conditions and metabolic disorders.
• Provides differential diagnosis and monitoring for varied internal diseases.
• Practices at a JCI-accredited hospital that serves over 500,000 patients annually.
• Performs diverse diagnostic screenings, including heart, cancer, and endocrine check-ups.

Dr. Oguz Acar is a neurologist at Memorial Şişli Hospital in Istanbul. He is a co-author of the textbook 'Advances and Technical Standards in Neurosurgery'. Dr. Acar specializes in treating brain and spine conditions. He manages cases of glioma, epilepsy, and various movement disorders. Dr. Acar works at Turkey's first JCI-accredited medical center.

• Published over 110 scientific papers on neurological care.
• Treats complex conditions like spine tumors and skull injuries.
• Provides care for patients with herniation and nervous disorders.
• Practices at a hospital serving patients from 160+ countries annually.

Dr. Cagatay Cetinkaya is a breast and thoracic surgeon at Memorial Atasehir Hospital. He treats conditions requiring surgical intervention within the chest and breast areas. Dr. Cetinkaya previously served as the Chief Physician at Bilecik Golpazari State Hospital. He completed his clinical research training at Marmara University Faculty of Medicine.

• Specializes in thoracic surgery and breast surgery procedures.
• Was the lead physician at a state medical facility in Bilecik.
• Works at Memorial Şişli, the first hospital in Turkey to earn JCI accreditation.
• Practices within a medical group that reports a 90% organ transplant success rate.