Urologist · Andrologist · Male Aesthetic Specialist. Over a decade of dedicated practice in non-surgical penile enhancement. Every procedure at Fill in Istanbul is performed personally — and every follow-up signed off personally.

Prof. Dr. Zülfü Sertkaya is a urologist and andrologist who has, over more than a decade, built his practice around the non-surgical, aesthetic side of men's genital health. He has performed several thousand penile girth enhancement procedures with hyaluronic acid filler, using the cannula technique, across an international patient base from more than thirty countries.
Prof. Dr. Sertkaya's practice is deliberately narrow. Rather than offering a general menu of male aesthetic treatments, he has concentrated on the small cluster of interventions that have the strongest evidence base, the cleanest safety profile, and the most predictable cosmetic outcome. In practice this means:
Treatments outside this focused list — extensive surgical interventions, permanent implants for cosmetic girth, or work that falls squarely within functional andrology (severe erectile dysfunction requiring an inflatable penile implant, for example) — are referred to colleagues in collaborating specialist centres in Istanbul.
Every consultation begins with a single question: is this treatment the right treatment for this patient, at this time? A surprising proportion of men who come to us have not fully considered whether HA girth filler addresses what they actually want. Some are more concerned about length than girth — for whom different counselling is indicated. Some are worried about erection quality — for whom PRP, lifestyle changes, or medical therapy is more relevant. Some are in a phase of life (acute stress, relationship change) where no aesthetic intervention is advisable until the underlying situation resolves.
We say no to a meaningful number of consultations. Not many clinics in this market do. It is — in our view — one of the most important things a specialist owes the patient.
The single defining feature of Prof. Dr. Sertkaya's clinical technique is the exclusive use of the blunt cannula. Over hundreds of procedures he has refined a specific injection architecture: a single ventral entry, a precisely mapped fan pattern of retrograde threads, and a methodical moulding protocol immediately post-injection. The technique is described in detail on the Procedure page.
He does not, under any circumstances, delegate the injection to another staff member. He does not rotate procedures to residents, trainees, or "assistant aestheticians". If, for any reason, he is not available on your planned date, we reschedule — we do not substitute.
Our patients consistently describe the consultation experience as "different from what they expected". Specifically:
From the first online message to the in-person consultation, I felt I was talking to a physician, not a salesperson. Everything was explained. Every question was answered. Every alternative was discussed. I made my decision with more confidence than I have with any medical consultation before. — International patient, 2024
What I valued most was that Dr. Sertkaya was willing to tell me that I did not need the maximum volume — and in fact recommended a more conservative result. He could have upsold me and didn't. That told me everything. — International patient, 2024
Initial consultations with Prof. Dr. Sertkaya are conducted in Turkish or English directly, or through a translator if you prefer to consult in Arabic, German, Italian, or French (we have regular coordinators fluent in each). Day-to-day communication during your treatment window runs through a dedicated WhatsApp line, with Prof. Dr. Sertkaya personally responding to medical questions within 24 hours during normal working days.
In-clinic availability is Monday to Saturday, with Sundays reserved for emergencies and urgent reviews. International consultation video calls are scheduled across European, Middle Eastern, American, and East-Asian time zones on request.
Every consultation with Prof. Dr. Sertkaya's clinical team is free and carries no obligation. The fastest route is WhatsApp; the written route is the contact form. Typical response time is under 2 hours during business hours (09:00–20:00 Istanbul time, GMT+3) and within 24 hours outside them.
A private, unhurried online consultation. No pressure, no obligation. We will answer every question you have — clinical, procedural, logistical.