Our Staff


Patrick H. Bitter, Sr., MD

Cosmetic Dermatologist Epi Center Medical Associates
and Co-Founder Epi Center MedSpa

World-recognized, Dr. Patrick Bitter, Sr. has been practicing in the San Francisco Bay Area for over 45 years. As a cosmetic dermatologist, his passion is skin rejuvenation and laser technology. He began his work with aesthetic lasers in 1979. It is with this dedication and devotion that he conceived one of the most sought after procedures around the globe, the PhotoFacial.

In 1995, he was one of the first to purchase Intense Pulsed Light technology and began developing treatment protocols for skin rejuvenation. In 1998, he went public with his research and introduced the PhotoFacialSM procedure. This treatment, also known as IPL PhotoRejuvenation, revolutionized skin care and is now performed around the world.

He performed FDA clinical trials for hair removal, collagen, and several laser procedures –
all treatments that have shaped the industry today. As such, he is an advisor to many international laser technology companies and frequently lectures on the subject. He has trained physicians from all over the world. He has also assisted in the development of five skin care products.

For his tremendous contribution to the industry of dermatology and medical cosmetics, Dr. Bitter was voted Dermatologist of the Year in 2013 and received an award on behalf of the American Cancer Society, given by Lynne Cheney, the wife of former Vice President Dick Cheney. In his spare time, Dr. Bitter has run 42 marathons, 5 ultra marathons and multiple triathlons, including the Ironman in Hawaii.


Michael Rokeach, MD

Associate Medical Director
Epi Center Medical Associates

Formerly, Chief of Staff at California Pacific Medical Center, Dr. Rokeach has joined Epi Center MedSpa to assist Dr. Bitter and provide the best possible medical care and expertise in treating patients. Dr. Rokeach studied at the University of Florida and went on to medical school at the University of Miami. He has always had an interest in dermatology and enjoys evaluating and treating acute skin diseases and aging skin. The rapid improvement of skin and the long lasting results that our patients experience due to the techniques honed at the MedSpa is rewarding for both the patient and the provider.


Margaret Mitchell

CEO and Co-Founder

Margaret Mitchell is a nationally renowned practice management consultant who specializes in developing and managing aesthetic and cosmetic practices. For over 30 years, Margaret has been dedicating her passion to bringing much needed industry leadership to the medical spa and cosmetic services field.

Margaret began working with Dr. Bitter in 1996, transforming his medical practice from general dermatology to cosmetic, and developed the marketing that introduced the PhotoFacial procedure. Together, in 1998, Margaret and Dr. Bitter conceptualized and opened the first medical spa of its kind in the country, Epi Center MedSpa, to provide a spa-like experience to those having cosmetic treatments. In 2008, Margaret went a step further and re-opened Epi Center MedSpa as the first LEED certified MedSpa in the nation, receiving a proclamation from the former Mayor of San Francisco, Lt. Governor Gavin Newsom. The MedSpa also follows the responsible environmental principles established by William McDonough, American designer, advisor, author and thought leader and co-author of Cradle to Cradle: Remaking the Way We Make Things. In an effort to give back to the community, Margaret also implemented the Centered On You Program through the MedSpa, supporting local charities and non-profit organizations in the Bay Area.

Margaret’s concept leads the way in providing the ideal experience along with optimal treatment results. She offers guests of the spa, and the medical practice, personalized and comprehensive skin rejuvenation plans, encouraging those to ask questions and educating them how to optimize their results.

In addition to Epi Center MedSpa, Margaret is the President of Aesthetic Marketing Concepts, LLC, a medical marketing and advertising firm, which she founded and opened in 1994.

She is a member of the San Francisco Ballet Auxiliary and Vistage International CEO Group.

Margaret had a 16-year career as an adjudicator and competitive ballroom dancer specializing in International Latin and American Smooth ranking 5th in the country.


Shilpa P. Vichare, PA

Physician Assistant
Epi Center Medical Associates

Shilpa received her NCCPA Certification in 1999 and became a licensed State of California Physician Assistant in 2000, specializing in all aspects of general and cosmetic dermatology, including detailed skin exams, diagnosis, appropriate surgical treatment and follow up, and patient education and counseling. At the Epi Center MedSpa, Shilpa provides a variety of treatments such as BOTOX® Cosmetic, Dysport, dermal fillers including Restylane, Juvederm and Radiesse, Skin Rejuvenation including Ultherapy, IPL PhotoFacial Elite, Microneedling, Fractora, and Pixel Skin Resurfacing, Velashape, Sclerotherapy, PDO Nova Threads, and laser hair removal. Shilpa is also proficient in treating a variety of dermatologic disease including but not limited to Actinic Keratosis, Acne Vulgaris, Rosacea, Seborrheic Dermatitis, Seborrheic Keratosis, Psoriasis, Basal/Squamous Cell Carcinoma, Dysplastic Nevi, Verrucous lesions, Lichenoid Dematoses, Fungal Infections of the skin, Onychomycosis, Alopecia, Viral Exanthems, Uricaria, Eczema, Atopic Dermatitis, and more.

Fluent in Hindi.


Arlene Vicencio, PA

Physician Assistant
Epi Center Medical Associates

Arlene comes to Epi Center MedSpa with a California State Physician Assistant License (NCCPA Certification) specializing in weight management as well as laser and medical grade cosmetic treatments. She heads up the HCG Weight Loss program at the Epi Center, including providing patients with weight reduction progress and personalized programs.

With over 10 years experience, Arlene’s expertise in non surgical skin care includes Skin Rejuvenation, Pixel Resurfacing, Ultherapy, BOTOX® Cosmetic and Dysport®, Dermal Fillers (Restylane®, Perlane®, Juvéderm™, Sculptra®), Intense Pulsed Light (IPL), PhotoFacialSM therapy, Thermage, CO2 Fractional laser (Fraxel), Sclerotherapy for Leg Veins, cosmetic laser procedures including tattoo removal, laser hair removal, and Medical-Grade Skin Care Products.

Fluent in Tagalog and Spanish


Inessa Samodeeva, RN

Master Injector – Aesthetic Nurse Specialist
Epi Center Medical Associates

Inessa studied and received her MD from Vitebsk Medical School in Belarus. Once coming to the United States she focused on practicing aesthetic medicine as well as prenatal care. Inessa joined Epi Center MedSpa in 2002. She is expertly skilled at performing every medical treatment we offer.  She specializes in non-surgical facelift procedures such as PDO Nova Threads,  BOTOX Cosmetic/Dysport, Restylane, Lyft, Silk, Juvederm, Voluma and many other dermal fillers. Inessa trained directly with Dr Bitter in 2002 and stays abreast of the latest in medical research and upgrades implemented for  PhotoFacial, Fractional Resurfacing, Sclerotherapy, Tattoo Removal, Clinical MicroNeedling and Skin Rejuvenation. With the best possible medical care and expertise in aesthetics, Inessa creates personalized treatment programs for every patient she sees. Inessa is passionate about educating patients about skin care and helping people to look as young as they feel.


Adriana E. Ibanez, RN

Aesthetic Nurse Specialist
Epi Center Medical Associates

Adriana received her Bachelor of Science in Nursing from San Jose State University in 2011 and is licensed by the State of California. She began her career in aesthetics in 2011 and is passionate about creating custom treatment programs for patients using her experience in cosmetic and general dermatology. Adriana provides comprehensive patient care with compassionate customer service and an educational experience. She performs the full scope of non surgical cosmetic procedures including full face volume replacement using Restylane, Lyft, Silk, Voluma, Juvederm, Vobella, Belatero , Kybella, BOTOX and Dysport, PhotoFacial IPL, fractional and laser skin tightening and resurfacing, Ulthera, Tattoo removal, and body contouring procedures such as CoolSculpting, CelluSculpt, and medically supervised weight loss. In addition to the excellent care she provides at the Epi Center MedSpa, she continues her practice of Medical Dermatology at Kaiser Permanente. She is passionate about helping her patients achieve their aesthetic goals and delivers highly personalized care and outstanding results to her clients.


Evelyn Blumin, RN

Aesthetic Nurse Specialist
Epi Center Medical Associates

Evelyn graduated from of the University of San Francisco School of Nursing in 1985. She specializes in IPL/Photofacials, laser treatments, laser hair reduction, clinical microneedling as well as  injectables fillers, Botox Dysport, and Kybella. She has certifications in multiple Intense Pulsed Light and laser technologies, BOTOX® Cosmetic and Restylane, Juvederm fillers. Evelyn works every Saturday at the Epi Center MedSpa. She also works for a plastic surgeon’s office a few days a week where she performs similar procedures. Her passion has always been skincare and aesthetics. Evelyn’s goal is to provide each client with a complete and individualized solution for facial and body rejuvenation.

Evelyn is fluent in Russian.


Kelly Ferrante, LE

Aesthetic Department Manager/Licensed Aesthetician

Kelly began her career in the beauty industry in 1997 as a makeup artist. Kelly obtained her Bachelor of Science in Social Sciences and Bachelor of Arts in Communications. Working with Smashbox Studios, Christian Dior, Stila & M.A.C., Kelly was specializing in promotional events, lectures, wedding/bridal parties and one-on-one consultations. The desire for more a creative “avant-garde” makeup career inspired Kelly to move to San Francisco, where she began her involvement with fashion agencies (modeling/makeup), music videos, fashion shows, print work, and retail websites. As her career took off, Kelly was approached by the creator of “Makeup Gourmet” Chris Scott, to co-host his cable television show. Kelly continued her training with some of the Bay Areas most prominent Dermatologists and Cosmetic Surgeons; specializing in pre and postoperative care, acne patients, chemical peels, clinical/deep facials, microdermabrasion, and permanent makeup. In addition to managing the aesthetic department at the Epi Center, Kelly continues to work in all realms of the “Beauty” business, creating a balance between skincare and makeup.


Melissa (Mel) Ruiz, LE

Licensed Aesthetician

Melissa (Mel) Ruiz has been practicing Esthetics since 2007. In 2008, Melissa became a licensed Clinical Aesthetician, receiving a degree from the Evergreen Beauty College in San Jose, California. Mel began her career as a makeup artist at the prestigious Preston Wynne Spa in Saratoga California. She then joined the highly coveted team at Aveda Spa at Santana Row in San Jose, California where she became certified in skin-wise one and two. Mel specializes in sundamaged skin, acne and acne scars, dehydrated and aging skin and, of course, customizing clinical facial treatments in a way that you have the ultimate spa experience. She offers THE MOST relaxing facials that are also results-driven. Mel is known for her thorough extractions and exceptional neck and shoulder massage influenced by Ayurvedic and Lymphatic drainage techniques. Mel is ever evolving in the beauty industry honing in on her craft with product knowledge, current research, trends and training’s. Mel continues to pursue diverse studies in Chakra Balancing and Oncology skincare treatments. Her background in customer service gives her an in-depth understanding of all aspects of spa culture; from booking appropriate services, to catering to patient skincare needs while providing excellent clinical treatments.


Vanessa Pimentel

Front Office Manager 

Vanessa has worked in the hospitality industry for over 5 years. She is dedicated to helping patients achieve their aesthetic goals by being a warm and caring Patient coordinator. You will feel at ease with Vanessa during your visit because she is attentive, compassionate, and thorough. Vanessa will ensure that all of your questions are answered, and all of your expectations are addressed. Vanessa possesses strong communication skills, a calm and pleasant demeanor, and an innate ability to be warm and compassionate. She is responsible for greeting and registering patients in the facility as well as verifying correctness of patient demographic and privacy information. This winning combination ensures that you will receive exceptional service and care, while visiting Epi Center MedSpa.

Fluent in Spanish~ Se habla Espanol.


Stacey Lynn, MA, LVN

Medical Assistant

Stacey Lynn, MA, LVN, has over a decade of experience working in corporate healthcare from General Adult Medicine, Physical Therapy, Allergy, Dermatology, Cosmetic Dermatology, OB-GYN, Pediatrics and Pediatric Hematology/Oncology. Stacey came to Epi Center MedSpa in 2015 and is happy to work in a private practice that provides a highest quality of patient care in an acute setting! You will find Stacey alongside any of our talented medical providers as support staff. She is also an experienced practitioner of CoolSculpting.

Stacey has studied Liberal Arts and Theater in her Undergraduate Studies at Holy Names University, Oakland, CA and will soon attend USF for the MSN (Master of Science in Nursing) program in 2017.

Stacey enjoys volunteering with several local, charitable organizations including the nearest and dearest to her heart which is Support For Families Of Children With Disabilities.


Pernella Sommerville

Public Relations & Communications Specialist

Pernella Sommerville was a welcome addition to the EpiCenter MedSpa team in early 2014 with expertise as a leading consultant in Public Relations, Marketing and Event Planning for both national and international markets. With over 15 years experience in public relations/special events, she applies her strong expertise in people/social skills, data, relationship building and long-term strategic planning. Previous to and in conjunction with ECMS, Pernella held various positions as Project Manager for Leftwich Events Specialists, Director of Industry Development and Administration/Director of Campus Life and Manager of Public Relations for Academy of Art University, Director of Membership Development, Redlands Chamber of Commerce, Manager, Mission Aviation Fellowship Foundation, Lecturer and Trainer for the Fashion Institute of Design and Merchandising and Clinician, Chaparral Treatment Center. Pernella Sommerville has led project valuation, negotiation processes, corporate business development and new client systems. In her first six months with EpiCenter MedSpa Pernella increased patient satisfaction and communications by more than 30%. Pernella Sommerville holds a Master of Science degree in Clinical Psychology, Bachelor of Arts degree in Psychology and Certificate in Public Relations. She is an active member of the Junior League of San Francisco.