A Leader & Innovator In The Field

Dr. Michael Zenn has a long history of excellence in the field of breast reconstruction. He was the lead reconstructive breast surgeon at UNC-Chapel Hill from 1996-2000, and the Vice Chief and Director of Resident Training at Duke University until 2017. During this time, he worked closely with other oncological professionals on interdisciplinary teams at the UNC Lineberger Comprehensive Cancer Center and the Duke Cancer Center. Dr. Zenn has an abundance of experience in every established breast reconstruction technique. In fact, Dr. Zenn was the first plastic surgeon to perform DIEP Flap reconstructions in North Carolina nearly two decades ago.

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An International Authority

Dr. Zenn literally “wrote the book” on Breast Reconstruction. His two-volume textbook, Reconstructive Surgery, is essential reading for plastic surgery residents and surgeons worldwide. After performing thousands of breast reconstructive surgeries over his career, Dr. Zenn is proud to have developed the Zenn Delay procedure for immediate breast reconstruction.

The Zenn Delay

The Zenn Delay is a revolutionary reconstructive surgery that allows for the conservation of the nipple and breast skin following a mastectomy for most patients, even those previously irradiated. Additionally, the Zenn Delay significantly reduces the complication rates and shortens the standard treatment time by several months. Plastic surgeons around the world now perform the Zenn Delay to deliver safer and more efficient care and ultimately, a more aesthetically pleasing cosmetic result.

Limitations Of Traditional Reconstructive Surgery

Breast cancer surgeons need only remove the underlying breast tissue during a mastectomy. Due to the popularity of the Nipple Sparing Mastectomy (NSM), once that tissue has been removed, there is ample skin and a nipple complex still present. This is optimal because a breast reconstruction that uses a patient’s own nipple and breast skin will yield a more beautiful and natural-looking cosmetic result. Traditionally, the way to accomplish this is to have patients go through months of tissue expansion to prepare the breast for the final reconstruction.

The Role of Tissue Expanders

The success of a nipple-sparing mastectomy depends on having a good blood supply after the surgery. The nipple and breast skin require this blood supply to survive, but are accustomed to receiving blood supply from the breast tissue that has been removed. Therefore, complications including loss of breast skin or loss of the nipple can be as high as 50% if reconstruction is attempted at the time of mastectomy. For this reason, most patients don’t receive a final breast implant in the same operation as the mastectomy.

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How Tissue Expanders Function

Instead, most plastic surgeons place a tissue expander at the time of mastectomy. Initially, this tissue expander has much less volume than the required implant. The tissue expander places less pressure on sensitive mastectomy skin, thereby encouraging the development of a new blood supply. 

Since the process of tissue expansion usually takes months to achieve the desired size, the nipple and breast skin have time to regain the blood supply they need to survive. Approximately three months after mastectomy and expander placement, breast reconstruction patients undergo a follow-up operation to replace the now fully expanded tissue expander with a final implant.

Problems With The Tissue Expansion Approach

Despite widespread use, tissue expanders present several drawbacks:

  • Tissue expansion requires weekly office visits to slowly increase the volume of the expander.
  • Patients report that as the expander increases in size, the breast area is painful (tight).
  • It can be challenging to wear clothes and look “normal” during the expansion process.
  • During the months the tissue expander is in place, the aesthetics of the natural breast may permanently diminish. 
  • Skin elasticity, scar contracture, and the expansion process can change the position of the nipple and the appearance of the breast. This makes the recreation of the natural breast difficult, if not impossible.

Dr. Zenn has decades of experience in nearly every established breast reconstruction technique (DIEP, SIEA, GAP, TUG, etc.). As a result of this experience, he discovered that patients only need about two weeks after the mastectomy for their nipple and breast skin to regain a proper blood supply, not months, as traditionally thought. Based on this revelation, Dr. Zenn created the Zenn Delay.

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The Zenn Delay Technique For Breast Reconstruction

With the Zenn Delay, patients undergo a mastectomy and then two weeks later a final reconstruction that results in breasts that look attractive and natural. The technique extends the option of a nipple-sparing mastectomy to patients who previously were not considered candidates: those with large breasts, patients who were previously irradiated, and patients who had undergone a previous breast surgery.

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First, The Mastectomy

The process begins when a patient has a nipple-sparing mastectomy with their breast surgeon. Note, patients may not be offered this option unless they specifically ask about “nipple-sparing,” as not all breast surgeons perform this surgery. If the surgeon does not perform this type of mastectomy, the patient should consider a second opinion with a surgeon who is familiar with this very common technique.

Patients will not undergo reconstruction on the same day as the mastectomy. This can be confusing for some patients. Herein lies the magic of the technique: allowing the skin and nipple to simply recover with no additional stress on the area with an implant or an expander. The only thing the breast surgeon needs to do to prepare for the reconstruction is place a surgical drain to prevent fluid buildup.

The Post-Mastectomy Examination

One week after the mastectomy, the patient will see Dr. Zenn at Zenn Plastic Surgery in Raleigh, North Carolina. During this appointment, Dr. Zenn examines incisions and removes the drains. In the second week following mastectomy, the patient should relax and continue to heal.

Dr. Zenn’s research shows that two weeks of “delay” is optimal for the skin to recover from the mastectomy. During the two-week delay, the chest will be flat, and pain should be minimal. (in fact, most of the pain with immediate reconstruction comes from placing the implant or expander under the chest muscle, not from the mastectomy itself.) By comparison, patients who receive a partially filled tissue expander at the time of mastectomy generally look flat as well during this time, because proper expansion does not begin for at least two weeks.

All reconstructive breast surgery is performed at REX Hospital in Raleigh NC

Finally, The Breast Reconstruction

Two weeks following a mastectomy, the patient will have the plastic surgery procedure. Dr. Zenn will recreate the breast by placing an implant in front of the pectoralis muscle. This placement greatly reduces any potential postoperative pain. Because the skin and nipple now have an excellent blood supply, there is less concern about them not surviving.

The Zenn Delay uses a patient’s own breast skin and preserves the nipple complex, when safe from a cancer standpoint. Breast tissue is replaced with an implant two weeks after mastectomy, completing the reconstruction. This entire process is completed months before the traditional tissue expander approach.

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Advancing The Field of Breast Reconstruction

Plastic and Reconstructive Surgery, the official academic journal of the American Society of Plastic Surgery, has reported on patients who Dr. Zenn has treated with the Zenn Delay. Even high-risk patients did extremely well after this surgery and benefited from outstanding cosmetic results with no nipple or skin loss. Since publishing his findings in 2015, Dr. Zenn has traveled the world presenting to and teaching other surgeons about the procedure. Plastic surgeons around the world now perform the Zenn Delay to deliver safer and more efficient care.

Dr. Zenn's Breast Reconstruction Patient Reviews


I had bilateral mastectomies due to BRACA 1 gene mutation. Dr. Zenn performed immediate skin and nipple sparing reconstruction with silicone implants. My breasts look better now than they did before the surgery.


Dr. Zenn is an amazingly talented plastic surgeon and is also a gentle, kind funny man, making a complicated surgical procedure and follow up so much easier than it would have been otherwise. He listened carefully and was responsive to my needs.


As an experienced provider, most times I set the bar a little to high, but Jo Ann Garofalo, RN and Dr. Zenn consistently sailed right over it. If you are looking for seamless, comprehensive, compassionate care with superior surgical talent, consider ...


Dr. Zenn, and his assistant, JoAnn, took great care of me during my reconstruction. It was a long hard process that included two unexpected set backs but they handled everything so warmly and professionally. I was kind of sad when everything was fina...


My experience was amazing. The care I received was very professional, yet caring and attentive by both Dr Zenn and his Nurse. The surgery took long hours but has been very successful. I would refer Dr Zenn to anyone who needs plastic surgery.


I LOVE Dr. Zenn. I had a double mastectomy in 2012 and he did my reconstruction. I had expanders with silicone implants and am really thrilled with the results. My husband is too!

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Schedule A Consultation Today

Dr. Zenn is committed to seeing the technique adopted as the standard of care, enabling women everywhere to have the most beautiful outcome possible. More information on Zenn Delay here. Find the original scientific article here. To find out more about how Dr. Zenn can help you, schedule a consultation with him at Zenn Plastic Surgery in Raleigh, North Carolina, today.

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