About

Diana L. Farmer, M.D., F.A.C.S., is a Professor of Surgery and the Chair of the Department of Surgery at UC Davis. Her role involves leadership within the department, overseeing surgical education programs, research initiatives, and clinical services. The department encompasses a wide range of specialties including burn surgery, cardiac surgery, colorectal surgery, endocrine surgery, general thoracic surgery, pediatric surgery, plastic surgery, surgical oncology, transplant surgery, trauma and acute care surgery, and vascular surgery. Dr. Farmer's position indicates her significant contribution to advancing surgical practices and education at UC Davis, although specific details about her research focus or prior background are not provided in the page text.

Research topics

• Medicine
• Internal medicine
• Obstetrics
• Pediatrics
• Anesthesia
• Biology
• Family medicine
• Surgery
• Physical therapy

Selected publications

• Cellular Therapy for In Utero Repair of Myelomeningocele (the CuRe trial): neurosurgical repair video

  Neurosurgical Focus Video · 2026-04-01

  articleOpen access

  The Management of Myelomeningocele Study (MOMS) established that prenatal repair of myelomeningocele (MMC) improved the rate of ventriculoperitoneal shunt insertion for the treatment of hydrocephalus, compared to postnatal repair. While there was mild improvement of motor function, most children were unable to ambulate independently. Therefore, the ongoing phase 1/2a clinical trial Cellular Therapy for In Utero Repair of Myelomeningocele (CuRe trial) aims to further improve distal neurological function using placenta-derived mesenchymal stem/stromal cells seeded on an extracellular matrix (PMSC-ECM) to augment open fetal repair of MMC. Here, the authors present a video of the neurosurgical repair using the PMSC-ECM. The video can be found here: https://stream.cadmore.media/r10.3171/2026.1.FOCVID25229.

  PublisherDOI

• Exploring the Evolving Landscape of Fetal Diagnosis and Therapy: A Quantitative Analysis and Clinical Survey

  Fetal Diagnosis and Therapy · 2026-01-20

  articleOpen access

  INTRODUCTION: The last 40 years have seen an increase in fetal diagnosis and therapy centers and the emergence of professional societies such as IFMSS, NAFTNet, iFetus, Eurofetus, and ISPD. Despite the progress and cross-collaboration, it is still unclear what resources are needed for the creation of new fetal diagnosis and treatment centers (FDTCs). Our study aimed to ascertain the key resources essential for effective FDTC implementation. METHODS: A cross-sectional study using a questionnaire was distributed to providers at North American FDTCs. The questionnaire ranked the importance of providers, facilities, interventions, and resources. Data analysis used descriptive statistics and series cross-tabulations for significance. RESULTS: Overall, 40.2% completed the questionnaire. Maternal-fetal medicine (MFM) specialists and pediatric surgeons (92%) predominated. Most centers were >10 years old. Critical resources included MFM providers, a dedicated nurse coordinator, high-resolution US capabilities, needle-based interventions, and patient access to an FDTC close to their home. Although specialty-based differences were not significant between newer and long-established centers, centers older than 10 years ranked additional surgical specialties and a mandatory reporting system as more important. CONCLUSION: Our findings offer valuable insights into the perspectives of fetal therapy providers, informing the strategic allocation of resources for establishing new FDTCs.

  PublisherOA PDFDOI

• Feasibility and safety of cellular therapy for in-utero repair of myelomeningocele (CuRe Trial): a first-in-human, phase 1, single-arm study

  The Lancet · 2026-02-01 · 2 citations

  articleOpen access1st authorCorresponding

  BACKGROUND: The Management of Myelomeningocele Study (MOMS) trial established the benefit of in-utero repair of myelomeningocele, with a decreased need for ventriculoperitoneal shunt placement. However, although there was some improvement of motor function, over half of the patients were unable to ambulate independently. Live placenta-derived mesenchymal stem cells (PMSCs) seeded on an extracellular matrix have shown promise in rescuing neurological function in the fetal ovine model of myelomeningocele. We aimed to evaluate the safety of this novel, living, stem cell product to augment the prenatal repair of myelomeningocele. METHODS: In this phase 1, first-in-human, single-dose, single-arm study, pregnant women who had fetuses diagnosed with myelomeningocele were enrolled in a staggered manner at University of California, Davis (UC Davis) School of Medicine, in Sacramento (CA, USA). Eligibility criteria were gestational age from 19 weeks to 26 weeks, upper boundary of the myelomeningocele defect between T1 and S1, hindbrain herniation shown by MRI, and normal karyotype. In-utero repair of the myelomeningocele was conducted with a single dose of topically applied allogeneic human PMSCs seeded on an extracellular matrix (Cook Biodesign Dural Graft [Cook Biotech; West Lafayette, IN, USA]). The PMSCs were generated from donated placentas collected from consented patients at the UC Davis Medical Center, and the cells were tested for identity, sterility, and viability 72 h before surgery. Primary safety endpoints included evaluation of the myelomeningocele repair site for healing, cerebrospinal fluid leak, infection, and unexpected abnormal growth or tumour formation. This study is registered with ClinicalTrials.gov (NCT04652908). FINDINGS: weeks) by caesarean delivery. At birth, all infants had an intact repair site with no evidence of cerebrospinal fluid leak, infection, or abnormal tissue growth. After treatment, MRIs showed reversal of hindbrain herniation and no evidence of tumour formation. No cell-mediated adverse events occurred. INTERPRETATION: This first-in-human treatment consisting of allogeneic, live stem cells showed no cell-related adverse effects. The therapy was assessed as sufficiently safe to proceed with non-staggered enrolment of 35 patients in a phase 1/2a trial. FUNDING: California Institute for Regenerative Medicine and Shriners Children's.

  PublisherDOI

• Integration of a Cultural Complications Curriculum Into a Surgery Department Conference

  JAMA Network Open · 2025-06-27

  articleOpen access

  This survey study assesses outcomes and perceptions of a cultural complications curriculum implemented at a Department of Surgery Morbidity and Mortality conference.

  PublisherOA PDFDOI

• Hybrid Extracellular Vesicles With Combined Functional Properties From Mesenchymal Stem Cells and Astrocytes for Targeted Neurodegenerative Disease Applications

  Journal of Extracellular Vesicles · 2025-10-01 · 1 citations

  articleOpen access

  Extracellular vesicles (EVs) have been investigated as nanotherapeutics and drug delivery systems for a wide range of disease indications. However, translational application of EVs is challenging due to their physical heterogeneity and variation in functional potency. The current study generated a novel hybrid EV formulation by membrane fusion of mesenchymal stem/stromal cell-derived EVs with astrocyte-derived EVs and defined its physicochemical and functional properties. Both EV populations have translational potential for neurodegenerative disease applications-a disease area with limited treatment strategies due to its complex disease biology requiring multi-faceted therapeutic approaches. However, individual EV sources lack the full set of therapeutic properties needed for comprehensive treatment. Stem cell-derived EVs possess general neuroprotective and anti-inflammatory effects but lack widespread blood-brain barrier penetration and specific neurodegenerative pathology targeting. Astrocytes are uniquely involved in key neuronal processes but are prone to adopting neuroinflammatory phenotypes in disease states. Using super resolution microscopy and quantitative proteomic analysis, we characterized, optimized, and validated a hybrid EV formulation for its brain cell targeting, neuroprotective function, and immunomodulatory capability. These results establish a platform for EV engineering through EV-EV hybridization and demonstrate the potential of one formulation for neurodegenerative applications.

  PublisherOA PDFDOI

• Prosthesis Embodiment in Lower Extremity Limb Loss: A Narrative Review

  Applied Sciences · 2025-04-29 · 3 citations

  reviewOpen access

  Lower limb prosthesis abandonment is a significant challenge, leading to reliance on walking aids, such as wheelchairs, which frequently do not match the patient’s needs and lead to increased morbidity. Prosthesis abandonment is driven by a lack of embodiment, the latter defined as the integration of a prosthetic device into one’s body schema. This review evaluates interventions enhancing embodiment through three dimensions: ownership, agency, and co-location. The aim of this narrative review is to ask what interventions are available to improve embodiment, and what dimensions of embodiment should be included in the standard of care for lower-limb amputation surgery and componentry development. This narrative is constructed through a thorough literature search on how the aforementioned dimensions of embodiment can be optimized. In the studies reviewed, standardization of embodiment metrics and longitudinal data are lacking, hindering clinical translation. Future work must prioritize patient-centered design, integrate multidimensional assessments, and address practical issues to expand eligibility for advanced interventions.

  PublisherOA PDFDOI

• In Utero Treatment of Lymphatic Malformations: A Narrative Review of the Literature, Considerations, and Future Directions

  Lymphatics · 2025-12-12

  articleOpen accessSenior author

  Lymphatic malformations are rare congenital anomalies that range from small, self-limited lesions to large, rapidly expanding masses capable of causing serious perinatal complications, including hydrops fetalis, polyhydramnios, airway obstruction, and fetal demise. Although most lesions are managed expectantly or postnatally, in utero interventions have been attempted in highly select cases where lesions threaten pregnancy viability or safety of delivery. Reported approaches include the perinatal option of ex utero intrapartum therapy, intrauterine ultrasound-guided cyst aspiration for decompression, intrauterine intralesional sclerotherapy with agents such as OK-432, and more recently, maternal pharmacologic therapy targeting the mTOR pathways. This review summarizes the available literature describing prenatal management of these lesions, including procedural techniques, maternal and fetal outcomes, and emerging strategies. Together, these findings highlight the potential promise and the caution necessary in translating postnatal therapeutic advances for lymphatic malformations to the prenatal setting.

  PublisherOA PDFDOI

• Transabdominal Fetal Oximetry via Diffuse Optics: Principled Analysis and Demonstration in Pregnant Ovine Models

  2025-10-02

  preprintOpen access

  Diffuse optics has the potential to offer a substantial advancement in fetal health monitoring via enabling continuous measurement of fetal blood oxygen saturation (fSpO 2 ). Aiming to enhance the sensing accuracy and to elucidate the foundational limits of Transabdominal Fetal Oximetry (TFO) via diffuse optics, we introduce a theoretical derivation, and a comprehensive pipeline for fSpO 2 estimation from non-invasively sensed diffuse light intensity values, which are leveraged to analyze datasets obtained through both simulations and in-vivo experiments in gold standard large animal model of pregnancy. We propose the Exponential Pulsation Ratio (EPR) as a key feature, and develop machine-learning models to fuse the information collected across multiple detectors. Our proposed method demonstrates a Mean Absolute Error (MAE) of 4.81% and 6.85% with a Pearson's r correlation of 0.81 (p<0.001) and 0.71 (p<0.001) for estimation of fSpO 2 in simulated dataset and in-vivo dataset, respectively. Across both datasets, our method outperforms the existing approaches, enhancing the accuracy of the fSpO 2 estimation and demonstrates its viability as a supplemental technology for intrapartum fetal monitoring.

  PublisherOA PDFDOI

• Fetal pHocus: A Novel Approach to Non-Invasive Fetal Arterial Blood pH Assessment via Near-Infrared Spectroscopy

  ACM Transactions on Computing for Healthcare · 2025-12-16

  articleOpen access

  Modern intrapartum fetal health assessments are currently limited to monitoring heart rate and spatial parameters, neglecting critical biomarkers that remain unmeasurable with today's clinical devices without performing surgery. Without precise evaluations of oxygen levels and blood acidity, clinicians are forced to rely on postnatal assessments to gauge fetal well-being, a delay that may obscure timely intervention. Fetal blood pH is a vital indicator of acid-base balance and cellular health, as any deviation could indicate potential health risks such as hypoxia and acidemia. In this study, we leverage the indirect relationship between pH and oxygen saturation to estimate fetal blood pH non-invasively using near-infrared (NIR) spectroscopy with wavelengths optimized for light transmission depth and oxygen saturation measurements. A convolutional neural network (CNN) extracts features from the acquired data, enabling accurate prediction of fetal blood pH using our machine learning (ML) model. Evaluation using hypoxic sheep models demonstrated an average prediction error of just 0.023 pH units, with all rounds maintaining errors below 0.05 pH units.

  PublisherOA PDFDOI

• Antibiotics alone versus appendicectomy for uncomplicated appendicitis in children

  The Lancet · 2025-01-01 · 2 citations

  letter1st authorCorresponding
  PublisherDOI

Frequent coauthors

• Aijun Wang

  Qilu Hospital of Shandong University

  201 shared

• Mark G. Shrime

  Massachusetts Eye and Ear Infirmary

  160 shared

• Dan Poenaru

  Montreal Children's Hospital

  156 shared

• Yasmine Yousef

  Joe DiMaggio Children's Hospital

  126 shared

• Jody A. Farrell

  University of California, San Francisco

  113 shared

• Steven C. Stain

  Lahey Hospital and Medical Center

  113 shared

• N. Scott Adzick

  University of Pennsylvania

  110 shared

• Laura F. Goodman

  Children's Hospital of Orange County

  110 shared

Education

• Fellow - Pediatric Surgery

  Children's Hospital of Michigan

  1995

• Chief Resident - General Surgery

  University of California, San Francisco

  1993

• Senior Resident - General Surgery

  University of California, San Francisco

  1992

• Resident - General Surgery

  University of California, San Francisco

  1991

• Postdoctoral Fellow - Surgical Oncology

  University of California, San Francisco School of Medicine

  1989

• Resident - General Surgery

  University of Washington School of Medicine

  1987

• Intern - General Surgery

  University of Washington School of Medicine

  1986

• MD, medicine

  University of Washington School of Medicine

  1983

• Pre-Med Studies

  College of Idaho

  1978

• Pre-Med Studies

  Harvard College

  1977

• Marine Biology

  MIT/Woods Hole Oceanographic Institute

  1977

• BA, Biology

  Wellesley College

  1977

• Marine Biology

  Stanford University Hopkins Marine Station

  1975

• Marine Biology

  Bermuda Biological Stations

  1974

Awards & honors

• Hibbard Williams Award for Extraordinary Achievement, UC Dav…
• President-Elect, American Surgical Association (ASA), 2021
• Regent, American College of Surgeons, 2019
• Dean’s Collaborative Research Award (DECOR), UC Davis, 2019
• Reinsch Endowed Lectureship