Driven by pioneering Body MRI radiologist Pejman (Peji) Ghanouni, MD, PhD, and a multidisciplinary team of experts, Stanford University has become a luminary site for focused ultrasound (FUS) research and is laying the groundwork for future clinical success.
“Peji is a model risk-taking innovator for focused ultrasound. He is persistently working inside and outside of Stanford to knock down barriers to progress,” says Foundation Chairman Neal F. Kassell, MD. “His enthusiasm for the technology is only surpassed by his passion for helping patients.”
His efforts fit well with Stanford’s dedication to investing in the future of medicine. “It has been very encouraging to see so many resources allocated to MRI-guided focused ultrasound,” says Dr. Ghanouni. “At a time when some institutions are demanding an immediate return on investment, our leadership has seen this as an exciting new tool. It wasn't even a matter of convincing them, they see this as part of our mission.”
Stanford has five FUS systems, including an INSIGHTEC Neuro system, two body systems, a prostate system, and the conformal bone system. The University has been a key site for several clinical studies and participates in ongoing trials using FUS to treat fibroids, essential tremor, prostate cancer, and bone metastases. In addition to conducting industry-funded research, Dr. Ghanouni has established a track record of obtaining highly competitive NIH grants to push the envelope of the technology as a solution for other difficult-to-treat conditions, including soft tissue tumors in children and adults, lower back arthritis, and bone metastases in the setting of orthopedic implants.
He currently treats about one FUS patient per week, having treated more than 70 patients in the past few years for bone metastases, uterine fibroids, essential tremor, and soft tissue tumors. Stanford’s leadership recognizes his critical role by enabling him to dedicate part of his time to FUS research and clinical care.
“Stanford is the ideal academic site for a focused ultrasound platform system like INSIGHTEC’s ExAblate,” says Suzanne LeBlang, Chief Medical Officer at the Foundation. “They have Peji at the nucleus to optimize expertise and efficiency across the institution; he works closely with multiple clinical disciplines that are eager to improve patient care. Combined with a world-class team of MR and ultrasound physicists and engineers, each specialty is able to research and implement the technology for a range of conditions.”
Dr. Ghanouni recently traveled to Virginia to meet with Foundation staff and to share his work at an event for Charlottesville community leaders. Read his investigator profile to explore the current landscape at Stanford, his experience with the technology, and his vision for clinical success
Focus on FUS
Dr. Ghanouni was exposed to FUS technology through a National Cancer Institute fellowship, which provided training in MRI and body imaging combined with research under the mentorship of Drs. Kim Butts Pauly and Gary Glazer, using FUS to treat bone pain from metastatic cancer. Stanford was a site for INSIGHTEC’s FDA pivotal trial for their ExAblate bone metastases system. His “hallelujah moment” came four years ago, after treating his first bone patient with FUS. The patient was a farmer whose melanoma had spread to his hip. The pain had not responded to prior Cyberknife radiation treatment, and he could barely endure the pain of sitting down to meet with Dr. Ghanouni. Days after the FUS treatment, he was sitting normally; a few months later, he was literally back in the saddle, riding his horse into the remote wilderness. “That was when I realized that we had an incredibly effective, non-invasive solution that could be applied to many challenging cases,” said Dr. Ghanouni.
Comprehensive Fibroid Center Model for Success
To help ensure FUS is included as a treatment choice for women with fibroids, Dr. Ghanouni collaborated with Drs. Bertha Chen and Deirdre Lum, colleagues in Gynecology, and Dr. David Hovsepian, from Interventional Radiology, to create the Stanford Fibroid Center. At the Center, a multidisciplinary team of physicians consults with each patient to assess her clinical profile and pelvic MRI scan, and then the team discusses an individualized optimal treatment plan. This clinical model has fostered close collaboration among the specialists. The model has also been a magnet for patients, who appreciate the opportunity to consult with physicians who are experts in surgical and non-surgical methods of treating fibroids. The large treatment volume has also enabled Dr. Ghanouni to select the optimal patients for FUS treatment. This Center has become a model of patient care, with very high levels of patient satisfaction.
Building Bone Metastases Treatment Practice
With the ExAblate system approved for commercial use in late 2012, Dr. Ghanouni is committed to building a robust practice for treating bone metastases at Stanford. Along with Drs. Quynh Le and Patrick Swift, colleagues in Radiation Oncology, and Kavitha Ramchandran, from Medical Oncology and Palliative Medicine, he has designed collaborative projects that will directly establish the value of FUS as an alternative to re-irradiation. Stanford is also reaching out to oncologists in the region to build a pipeline of referrals to the institution. The environment for reimbursement for bone metastasis treatment is very promising. As insurers across the US are starting to issue positive coverage policies for the treatment, the remaining barriers to reimbursement should soon be eliminated.
FUS as Promising Option for Soft Tissue Tumors
Dr. Ghanouni has been collaborating with Stanford orthopedic surgeon Dr. Raffi Avedian to conduct research using FUS to treat benign and cancerous soft tissue tumors in adults and children. While surgery, chemotherapy, and radiation are standard treatments for soft tissue cancers, they can cause significant co-morbidities, especially in patients with benign but locally aggressive tumors, such as desmoids. The results of their FUS research have been very encouraging. Not only is FUS able to non-invasively destroy tumor tissue, but it can also be administered repeatedly, allowing durable control of desmoid tumors. Their research offers hope in the future for FUS to help patients struggling with recurrences from malignant soft tissue tumors. While their work in malignant tumors is part of an NIH-funded phase 1 study, insurance companies recognize the value of FUS treatment of benign but symptomatic soft tissue tumors, and have been consistently reimbursing for these treatments.
FUS for Back Pain
Chronic lower back pain can be caused by the degeneration of the facet joint, and current therapies do not provide durable pain relief. FUS may be used to destroy the nerves around the facet joint without invasive surgery. Along with neurosurgeons Drs. Suzanne Tharin and John Ratliff, Dr. Ghanouni is conducting a study funded by the Focused Ultrasound Foundation to assess the safety and efficacy of this approach in 10 patients. The study is being conducted under the mentorship of Dr. Wladyslaw Gedroyc, who pioneered this technique in the UK.
FUS for Focal Prostate Cancer
Recent advances in MRI combined with targeted prostate biopsies have improved detection of prostate cancer that is clinically significant, yet small enough and sufficiently free of high grade features that there may be a high chance of cure by local treatment. Stanford’s pioneering team from Urology, including Drs. Geoffrey Sonn, Richard Fan and James Brooks, as well as leading prostate MR imaging researchers such as Drs. Graham Sommer and Bruce Daniel, are working with Dr. Ghanouni to launch a clinical trial using the ExAblate prostate MRgFUS system to treat localized prostate cancer. “We hope that this approach proves effective in eradicating focal, aggressive prostate cancer, while preserving quality of life,” says Dr. Ghanouni.
Preparing for Essential Tremor Treatment
The Stanford team, which includes Drs. Jaimie Henderson and Casey Halpern from Neurosurgery, Veronica Santini from Neurology, and Max Wintermark from Neuroradiology, will build on their experience from the ExAblate Neuro essential tremor pivotal trial by starting to treat patients under an FDA-approved continued access program that runs through the pivotal study completion and regulatory review process. “We have a database of patients who have contacted us and are interested in the continued access program,” says Dr. Ghanouni. “This additional treatment experience will enable us to continue to provide this treatment for our patients as we build our FUS brain team and prepare for the system to be approved by the FDA.”
Based on his diverse experience, Dr. Ghanouni recognizes some needs to optimize the technology and create new tools to maximize safety and efficacy. For soft tissue tumor treatments, he would like a conformal transducer system that can be placed anywhere on the body to minimize patient positioning time. He also needs this transducer to operate at higher frequencies to allow more precise treatment closer to structures such as nerves or skin. An improved positioning system would ideally incorporate a cooling device that would help protect tissue in the near and far fields when treating tumors in extremities. With these and other technical development efforts, Dr. Ghanouni’s clinical FUS practice has benefitted tremendously through collaboration with the laboratory of Dr. Kim Butts Pauly, a professor of Radiology and Bioengineering at Stanford.
Collaboration is the Key
Dr. Ghanouni credits a lot of the success of advancing FUS at Stanford to fostering a cooperative environment. “Clearly, there are unmet clinical needs in medicine, where non-invasive FUS treatment provides an elegant approach to therapy that can dramatically improve on available alternatives. I enjoy being able to work with colleagues across disciplines to treat patients with complicated needs through this simple, yet groundbreaking, approach. We confer on treatment strategies and also collaborate in spreading the word across the medical community,” says Dr. Ghanouni. “My colleagues and I author papers together and speak at different conferences to demonstrate how focused ultrasound is a valuable medical innovation that can be used by many specialties to improve patient care.”
Dr. Ghanouni's Key FUS Publications
Holbrook AB, Ghanouni P, Santos JM, Medan Y, Butts Pauly K. In vivo MR acoustic radiation force imaging in the porcine liver. Med. Phys. 2011 Sep; 38(9):5081. PMID: 21978053.
Ghanouni P, Gill H, Kaye E, Pauly KB, Daniel B. MR imaging-guided cryoablation for the treatment of benign prostatic hyperplasia. J Vasc Interv Radiol. 2011 Oct; 22(10):1427-30. PMID: 21961982.
Avedian RS, Gold G, Ghanouni P, Pauly KB. Magnetic resonance guided high-intensity focused ultrasound ablation of musculoskeletal tumors. Current Orthopaedic Practice. 2011; 22(4):303-308.
Holbrook AB, Ghanouni P, Santos JM, Dumoulin C, Medan Y, Butts Pauly K. Respiration based steering for high intensity focused ultrasound liver ablation. Magn Reson Med. 2013, March 4. PMID 2346051.
Hurwitz MD, Ghanouni P, Kanaev SV, Iozeffi D, Gianfelice D, Fennessy FM, Kuten A, Meyer JE, LeBlang SD, Roberts A, Choi J, Larner JM, Napoli A, Turkevich VG, Inbar Y, Tempany CM, Pfeffer RM. Magnetic resonance-guided focused ultrasound for patients with painful bone metastases: phase III trial results. J Natl Cancer Inst. 2014, Apr 23; 106(5). pii:dju082. PMID: 24760791.
Huisman M, Ter Haar G, Napoli A, Hananel A, Ghanouni P, Lövey G, Nijenhuis RJ, van den Bosch MA, Rieke V, Majumdar S, Marchetti L, Pfeffer RM, Hurwitz MD. International consensus on use of focused ultrasound for painful bone metastases: Current status and future directions. Int J Hyperthermia 2015 Feb 13:1-9. [Epub ahead of print] PMID:25677840
Ghanouni P, Butts Pauly K, Elias WJ, Henderson J, Sheehan J, Monteith S, Wintermark M. Transcranial MR-Guided Focused Ultrasound: A Review of the Technique and Application. AJR Am J Roentgenol. Manuscript in press.
Bitton R, Butts Pauly K, Ghanouni P. Improving Thermal Dose Accuracy in MRgFUS: A Prior Baseline Method of Long Term Thermometry. J Magn Reson Imaging. Manuscript accepted.
Avedian R, Gold G, Butts Pauly K, Ghanouni P. Is MR Guided High Intensity Focused Ultrasound a Feasible Treatment Modality for Extremity Soft Tissue Tumors? Clinical Orthopaedics and Related Research. Manuscript accepted.