Sharath Bhagavatula

Harvard Medical School | HMS · Department of Radiology

Abdominal percutaneous needle biopsies are commonly performed minimally invasive procedures to obtain tissue samples for histopathological diagnosis. Severe post-biopsy bleeding is uncommon but can be associated with prolonged hospitalization, additional interventions, morbidity, and death. Many factors may increase bleeding risk and various peri-p...

Purpose: To assess safety and feasibility of percutaneous MR-guided placement of an implantable microdevice (IMD) to evaluate in situ intratumor response to multiple pharmacologic agents in men with intermediate- and high-risk localized prostate cancer. Materials and methods: Biocompatible IMDs measuring 750um in diameter and 5 mm in length were...

Background There are multiple therapies for renal cell carcinoma (RCC), yet no personalized biomarkers exist that can guide optimal treatment for individual patients. We developed implantable microdevices (IMD) that can be placed within a target tumor using a standard small-gauge interventional needle under imaging guidance. The IMDs deliver spatia...

Systems that can image in three dimensions at cellular resolution and across different locations within an organism may enable insights into complex biological processes, such as immune responses, for which a single location measurement may be insufficient. In this Letter, we describe an in vivo two-site imaging probe (TIP) that can simultaneously...

Background Percutaneous microwave ablation (pMWA) is a minimally invasive procedure that uses a microwave antenna placed at the tip of a needle to induce lethal tissue heating. It can treat cancer and other diseases with lower morbidity than conventional surgery, but one major limitation is the lack of control over the heating region around the abl...

PET/CT guidance during percutaneous tumor ablation procedures combines metabolic and anatomic imaging, providing a powerful approach that can improve intraprocedural tumor visibility and ablation margin evaluation for a variety of cancers. This article reviews key advantages of the use of PET/CT as guidance for tumor ablation and describes the auth...

The selection of optimal therapies for ovarian cancer patients, especially in the recurrent setting, is hindered by a lack of biomarkers that predict responsiveness to specific treatments. An implantable microdevice (IMD) is a new technology to evaluate in situ drug responses in cancer. The IMD is 750 microns wide and 6 mm long, and it is implanted...

Purpose Disease control and survival following percutaneous ablation of hepatic epithelioid hemangioendothelioma (EHE) was studied retrospectively. Methods Six patients underwent 16 image-guided ablation procedures to treat 35 liver tumors from 2015 to 2022 (17 microwave ablation, 9 irreversible electroporation, 8 cryoablation, and 1 radiofrequenc...

Purpose The purpose of this study was to assess the feasibility and safety of using a bipolar radiofrequency track cautery device during percutaneous image-guided abdominal biopsy procedures in at-risk patients. Methods Forty-two patients (26–79 years old; female 44%) with at least one bleeding risk factor who underwent an abdominal image-guided (...

The lack of reliable predictive biomarkers to guide effective therapy is a major obstacle to the advancement of therapy for high-grade gliomas, particularly glioblastoma (GBM), one of the few cancers whose prognosis has not improved over the past several decades. With this pilot clinical trial (number NCT04135807), we provide first-in-human evidenc...

A First-in-Human Microdevice. Shown is a matrix assisted laser desorption/ionization–time-of-flight (MALDI-TOF) image of lapatinib delivered into a glioma by a penetrating intratumoral microdevice (IMD). The highest lapatinib concentration is shown in red and gray, and the lowest concentration is in blue. Peruzzi et al. report first-in-human use of...

This study assesses the feasibility and functionality of using a high-speed image fusion technology to generate and display PET/CT fluoroscopy images during PET/CT-guided tumor ablation procedures. Thirteen patients underwent 14 PET/CT-guided ablations to treat 20 tumors. An FDA-cleared multimodal image fusion platform received DICOM images pushed...

Purpose: To compare tumor and ice-ball margin visibility on intraprocedural PET/CT and CT-only images, and report technical success, local tumor progression, and adverse events rates for PET/CT-guided cryoablation procedures of musculoskeletal tumors. Materials and methods: This HIPAA-compliant, IRB-approved retrospective study evaluated 20 PET/...

Purpose: To assess outcomes following image-guided ablation of recurrent or unresectable intrahepatic cholangiocarcinoma (ICC). Materials and methods: In this retrospective study, 25 patients (14 female, ages 36-84) underwent 37 image-guided liver tumor ablation procedures to treat 47 ICC tumors (May 2004-January 2022). At initial diagnosis, 20...

Background There is uncertainty in the management of renal masses diagnosed as oncocytomas with image-guided percutaneous biopsy. Purpose To assess the reliability of a diagnosis of oncocytoma based on image-guided percutaneous renal mass biopsy and evaluate patient outcomes following different management strategies. Materials and Methods In this r...

Microtopography In article 2201585, Sajanlal R. Panikkanvalappil and co‐workers demonstrate an efficient tumor targeting strategy to deliver systemically administered nanoparticles (NPs) into solid tumors. This technique involves intratumoral implantation of micromagnets, which facilitate enhanced tumor accumulation of the novel multimodal magneto‐...

Tumor-infiltrating immune cells experience significant metabolic reprogramming in the tumor microenvironment (TME), and they share similar metabolic pathways and nutrient needs with malignant cells. This positions these cell types in direct nutrient competition in the TME. We currently lack a complete understanding of the similarities, differences,...

One of the major shortcomings of nano carriers‐assisted cancer therapeutic strategies continues to be the inadequate tumor penetration and retention of systemically administered nanoformulations and its off‐target toxicity. Stromal parameters‐related heterogeneity in enhanced permeability and retention effect and physicochemical properties of the n...

Graded index (GRIN) lens endoscopy has broadly benefited biomedical microscopic imaging by enabling accessibility to sites not reachable by traditional benchtop microscopes. It is a long-held notion that GRIN lenses can only be used as rigid probes, which may limit their potential for certain applications. Here, we describe bendable and long-range...

This study sought to quantify positron emission tomography (PET) and computed tomography (CT) components of patient dose and personnel radiation exposure during PET/CT-guided tumor ablations, and to assess the utility of a rolling lead shield for operator protection. Two operators performed 21 PET/CT-guided ablations behind a custom 25 mm lead shie...

The lack of reliable predictive biomarkers to guide effective therapy is a major obstacle for the advancement of therapy for high grade gliomas (HGG), and particularly glioblastoma (GBM), one of the few cancers whose prognosis has not improved over the past several decades. With this pilot clinical trial we provide first in human evidence that drug...

The lack of reliable predictive biomarkers to guide effective therapy is a major obstacle for the advancement of therapy for high grade gliomas (HGG), and particularly glioblastoma (GBM), one of the few cancers whose prognosis has not improved over the past several decades. With this pilot clinical trial we provide first in human evidence that drug...

Advances in the intratumor measurement of drug responses have included a pioneering biomedical microdevice for high throughput drug screening in vivo, which was further advanced by integrating a graded-index lens based two-dimensional fluorescence micro-endoscope to monitor tissue responses in situ across time. While the previous system provided a...

Embodying the principle of 'everything you need but still easy to read', this fully updated edition of Core Radiology is an indispensable aid for learning the fundamentals of radiology and preparing for the American Board of Radiology Core exam. Containing over 2,100 clinical radiological images with full explanatory captions and color-coded annota...

Objective: The purpose of this article is to report the translational process of an implantable microdevice platform with an emphasis on the technical and engineering adaptations for patient use, regulatory advances, and successful integration into clinical workflow. Methods: We developed design adaptations for implantation and retrieval, establ...

Percutaneously implanted miniaturized devices such as fiducial markers, miniaturized sensors, and drug delivery devices have an important and expanding role in diagnosing and treating a variety of diseases. However, there is a need to develop and evaluate anchoring methods to ensure that these microdevices remain secure without dislodgement, as eve...

By observing the activity of anti-cancer agents directly in tumors, there is potential to greatly expand our understanding of drug response and develop more personalized cancer treatments. Implantable microdevices (IMD) have been recently developed to deliver microdoses of chemotherapeutic agents locally into confined regions of live tumors; the ti...

Background Interventional photoacoustic imaging (iPAI) could improve ultrasound‐guided minimally invasive procedures by enabling high precision needle steering, target detection, and molecular and physiologic tissue assessment. However, iPAI capabilities including visualization field, imaging depth, and spatial resolution are not well understood in...

Background Percutaneous ablation for cT1 renal cell carcinoma (RCC) remains underused, partially because of heterogeneous and limited long-term outcomes data assessing recent cryoablation methods. Purpose To report intermediate- to long-term outcomes of image-guided percutaneous cryoablation of cT1 RCC and to compare outcomes for CT versus MRI guid...

Purpose Recently developed implantable microdevices can perform multi‐drug response assessment of cancer drugs in‐vivo, with potential to develop highly optimized personalized cancer treatment strategies. However, minimally invasive/interventional image‐guided methods of in‐vivo microdevice implantation, securement, and retrieval are needed for bro...

Anesthesia Outside of the Operating Room 2nd edition covers all aspects of providing anesthesia in settings outside of the main operating room, with a special focus on techniques, procedures and safety considerations. It discusses anesthetic concerns by procedure location, and includes selected latest guidelines from the American Society of Anesthe...

Anesthesia Outside of the Operating Room 2nd edition covers all aspects of providing anesthesia in settings outside of the main operating room, with a special focus on techniques, procedures and safety considerations. It discusses anesthetic concerns by procedure location, and includes selected latest guidelines from the American Society of Anesthe...

Image-guided renal biopsies have an increasing role in clinical practice. Renal mass and renal parenchymal biopsy indications, techniques, and other clinical considerations are reviewed in this article. Image-guided renal mass ablation shows significant promise and increasing clinical usefulness as more studies demonstrate its safety and efficacy....

Image-guided percutaneous, minimally invasive ablation techniques offer a wide variety of new modalities to treat tumors in some of the most medically complicated patients coming to our hospitals. The use of computed tomography, PET, ultrasound imaging, and MRI to guide radiofrequency ablation, microwave ablation, and cryoablation techniques now ma...

Image-guided percutaneous thermal ablation is increasingly utilized in the treatment of hepatic malignancies. Peripherally located hepatic tumors can be difficult to access or located adjacent to critical structures that can be injured. As a result, ablation of peripheral tumors may be avoided or may be performed too cautiously, leading to inadequa...

Image-guided renal biopsies have an increasing role in clinical practice. Renal mass and renal parenchymal biopsy indications, techniques, and other clinical considerations are reviewed in this article. Image-guided renal mass ablation shows significant promise and increasing clinical utility as more studies demonstrate its safety and efficacy. Ren...

Purpose: Advancements in and adoption of consumer virtual reality (VR) are currently being propelled by numerous upcoming devices such as the Oculus Rift. Although applications are currently growing around the entertainment field, wide-spread adoption of VR devices opens up the potential for other applications that may have been unfeasible with pas...

Background Measurement of mitral annulus (MA) dynamics is an important component of the evaluation of left ventricular (LV) diastolic function; MA velocities are commonly measured using tissue Doppler imaging (TDI). This study aimed to examine the clinical potential of a semi-automated cardiovascular magnetic resonance (CMR) technique for quantifyi...

Background We have developed a novel and practical cardiovascular magnetic resonance (CMR) technique to evaluate left ventricular (LV) mitral annular motion by tracking the atrioventricular junction (AVJ). To test AVJ motion analysis as a metric for LV function, we compared AVJ motion variables between patients with hypertrophic cardiomyopathy (HCM...

PurposeTo assess liver stiffness using magnetization-tagged magnetic resonance imaging (MRI) to measure the cardiac-induced motion in the liver of cirrhosis patients with known Child-Pugh scores.Materials and Methods Tagged MRI was performed using a 3T MR scanner on 52 cirrhosis patients classified into two groups: liver cirrhosis with Child-Pugh A...

PURPOSE We aimed to assess liver stiffness by using magnetization-tagged MRI to measure the cardiac-induced motion and deformation in the liver of cirrhosis patients with Child-Pugh scores. METHOD AND MATERIALS Tagged MRI was performed on 52 cirrhosis patients classified into 2 groups using the Child-Pugh score: liver cirrhosis with Child-Pugh A (...

PURPOSE We aim to calculate elastic modulus (stiffness) of the liver, using magnetization-tagged MRI and finite element modeling of cardiac-induced liver motion. METHOD AND MATERIALS Cardiac-gated tagged MRI was performed on 16 normal volunteers and 30 cirrhosis patients (18 Child-Pugh score A and 12 Child-Pugh score B/C), using 3T MRI systems (Ti...

PURPOSE We aim to assess cardiac diastolic function by three-dimensional volume tracking of the atrioventricular junction (AVJ) over the cardiac cycle with cine MRI. METHOD AND MATERIALS Conventional cardiac cine MRI with electrocardiogram gating was performed on 18 normal volunteers (35.8 +/- 12.8 years old), using 3T MRI systems (Tim Trio, Sieme...

We utilize time-resolved electrokinetic measurements in order to study the electrokinetic properties of silica and TOPAS microfluidic channels as a function of the time history of the fluid-solid interface. In pressure-driven flow through TOPAS microchannels, the zeta-potential as inferred from streaming potential measurements decays exponentially...

This paper combines new experimental data for electrokinetic characterization of hydrophobic polymers with a detailed discussion of the putative origins of charge at water-hydrophobe interfaces. Complexities in determining the origin of charge are discussed in the context of design and modeling challenges for electrokinetic actuation in hydrophobic...