Safety, Feasibility, and Patient-Rated Outcome of Sonolucent Cranioplasty in Extracranial-Intracranial Bypass Surgery to Allow for Transcranioplasty Ultrasound Assessment

Systematic Review of Commercially Available Clinical CMUT-Based Systems for Use in Medical Ultrasound Imaging: Products, Applications, and Performance

An emerging alternative to conventional piezoelectric technologies, which continue to dominate the ultrasound medical imaging (US) market, is Capacitive Micromachined Ultrasonic Transducers (CMUTs). Ultrasound transducers based on this technology offer a wider frequency bandwidth, improved cost-effectiveness, miniaturized size and effective integration with electronics. These features have led to an increase in the commercialization of CMUTs in the last 10 years. We conducted a review to answer three main research questions: (1) What are the commercially available CMUT-based clinical sonographic devices in the medical imaging space? (2) What are the medical imaging applications of these devices? (3) What is the performance of the devices in these applications? We additionally reported on all the future work expressed by modern studies released in the past 2 years to predict the trend of development in future CMUT device developments and express gaps in current research. The search retrieved 19 commercially available sonographic CMUT products belonging to seven companies. Four of the products were clinically approved. Sonographic CMUT devices have established their niche in the medical US imaging market mainly through the Butterfly iQ and iQ+ for quick preliminary screening, emergency care in resource-limited settings, clinical training, teleguidance, and paramedical applications. There were no commercialized 3D CMUT probes.

Health-related quality of life following cranioplasty - a systematic review

Cranioplasty is a neurosurgical procedure that repairs a defect in the skull Coupled with the underlying pathology cranioplasty associated morbidity can have a large impact on patient quality of life, which is often poorly explored. The objective of this systematic review was to identify patient-reported outcomes evaluating health-related quality of life following cranioplasty. The review protocol was registered on PROSPERO (CRD42021251543) and a systematic review was conducted in accordance with the PRISMA statement. PubMed, Embase, CINAHL Plus, and the Cochrane databases were searched from inception to 1 May 2022. All studies reporting HRQoL following cranioplasty were included. Reporting was assessed using the ISOQOL checklist and risk of bias was assessed using the Newcastle-Ottawa Scale or the Johanna-Briggs Institute Scale, as appropriate. A total of 25 studies were included of which 20 were cross-sectional and 2 longitudinal. Most studies utilized study specific questionnaires and Likert scales to assess HRQoL. The studies found a significant improvement in physical functioning, social functioning, cosmetic outcome, and overall HRQoL following cranioplasty. Further longitudinal studies utilising validated measurement tools are required to better understand the effect of cranioplasty at a patient level.

Bone Regrowth After Frontal Burr Hole Craniostomy: Natural History of 14-mm and 20-mm Burr Holes and Implications for Postoperative Trans-Burr Hole Ultrasound

BACKGROUND AND OBJECTIVE

Burr hole craniostomy is performed for ventriculoperitoneal shunt insertion and endoscopic third ventriculostomy in patients with cerebrospinal fluid disorders. These burr holes are increasingly being used as windows for postoperative ultrasound, an investigational alternative to computed tomography or MRI for follow-up imaging of ventricular caliber. However, bone regrowth reduces ultrasound visibility, and little is known about burr hole regrowth rates in adults. Our study evaluates burr hole regrowth patterns and implications for transcranial ultrasound imaging.

METHODS

We retrospectively analyzed 101 consecutive patients who had frontal burr hole craniostomy for new ventriculoperitoneal shunt insertion or endoscopic third ventriculostomy over a 3-year period. A mix of standard 14-mm burr holes and expanded 20-mm burr holes were used. Burr hole bone regrowth was assessed using serial follow-up computed tomography scans. Linear and logistic regression analyses examined if bone regrowth correlated with any clinical variables.

RESULTS

There was wide variability in rate and degree of burr hole regrowth. The average percentage closure was 25% at 6 months, with minimal additional closure over the following 18 months. The mean residual diameter for 14-mm and 20-mm burr holes stabilized around 9.4 mm and 15.4 mm, respectively. Bone regrowth was not associated with patient characteristics, including age, sex, skull thickness, or etiology of cerebrospinal fluid disorder. Rate of bone regrowth was similar between both cohorts.

CONCLUSION

Bone regrowth after burr hole craniostomy is common, even in elderly patients, occurring rapidly within the first 6 to 12 months and subsequently stabilizing. It is frequently severe enough to restrict ultrasound visualization. Regrowth could not be predicted with any investigated variables, so uniform techniques are needed to block regrowth to allow for longitudinal ultrasound imaging, such as full-thickness cylindrical burr hole implants.

Quantitative Analysis of Occipital Artery Bypass Donor Vessels by Ultrasonography and DSA

BACKGROUND

Occipital artery (OA) acts as a vital donor vessel in intra-cranialand extra-cranial bypass. Ultrasonography and digital subtracted angiography (DSA) are becoming increasingly important in the assessment of vascular morphology and hemodynamically; however, quantitative analysis of occipital artery bypass donor vessels by Ultrasonography and DSA are seldom discussed.

METHODS

A retrospective study involving 62 cases accepted occipital artery bypass to treat posterior circulation aneurysms or artery occlusion/stenosis. The characteristics of OA are collected and analyzed.

RESULTS

Occipital artery bypasses were performed to treat posterior circulation aneurysms in 34 patients and to treat posterior circulation artery occlusion or stenosis in 28 patients. Compared with the ultrasonography group, the DSA group had a greater diameter of OA, and Bland Altman analysis indicated that the discrepancy between the 2 groups was about 0.555 mm. Ultrasonography showed the characteristics of OA: the mean Peak Systolic Velocity (PSV) was 42.98 cm/s, the mean End Diastolic Velocity (EDV) was 8.811 cm/s, and the mean Resistance Index (RI) was 1.46. There were no statistical differences in the diameter of OA, PSV, EDV, and RI between the male group and female group, the elderly group and younger adult group or the left occipital artery group and right occipital artery group. However, compared with patients with posterior circulation aneurysms, patients with artery occlusion or stenosis were older and had higher PSV, RI, and greater diameter in occipital arteries. The mean diameter of occipital arteries was increased in the first postoperative years but reduced in 3 patients during 1 year follow-up.

CONCLUSIONS

Both ultrasonography and DSA were effective assessment methods of occipital artery bypasses, and the DSA group had a greater diameter of OA. Age, gender, and left or right sides had little effect on the diameter of OA, PSV, EDV, and RI. Posterior circulation occlusion or stenosis had higher PSV, RI, and greater diameter of the occipital artery when compared with posterior circulation aneurysms. Occipital artery bypasses could increase the diameter of OA in most cases.

Sonolucent Cranial Implants: A Window into the Future of Management of Neurosurgical Patients? A Systematic Review and Cost Analysis

BACKGROUND

Computeed tomography (CT) is a cornerstone of the identification and management of acute changes in neurosurgery patients. In addition to the monetary expense of CT scans, further costs are incurred due to the time of patient transport and radiation exposure. Ultrasounds (USs)offer a safe, inexpensive, and bedside alternative to CT but obstacles remain due to decreased penetrance in the adult skull. Sonolucent Cranial Implants (SCIs) offer a window for USs to view intracranial architectures.

METHODS

The authors performed a PRISMA guidelines-based systematic review of the literature. Information was extracted from included articles in regards to illness pathology, US imaging feasibility, comparison to standard imaging, infections, and revisions. Costs were collected in regards to price of implant and follow-up imaging.

RESULTS

A total of 226 articles resulted, of which 5 were included in the study. Ninety non-duplicate patients who received SCIs were analyzed. The pathologies of included patients is as follows: 51 patients were after extracranial-intracranial bypass, 37 after ventriculoperitoneal shunt placement for hydrocephalus, 1 after tumor resection, and 1 after cranioplasty following decompressive hemicraniectomy. All studies noted feasibility of US and comparability to standard imaging following SCI placement. Follow-up imaging with trans-sonolucent cranial implant ultrasound was estimated to save up to $4,000 per patient depending on the procedure.

CONCLUSIONS

Initial studies suggest that US imaging through SCIs is a safe and efficacious alternative to CT imaging in neurosurgical patients. Cost analysis suggests that SCI and subsequent US can offer a cost savings compared with current treatment.

Transcranioplasty Ultrasonography Through a Sonolucent Prosthesis: A Review of Feasibility, Safety, and Benefits

Data on the effectiveness of transcranioplasty ultrasonography through sonolucent cranioplasty (SC) are new and heterogeneous. We performed the first systematic literature review on SC. Ovid Embase, Ovid Medline, and Web of Science Core Collection were systematically searched and published full text articles detailing new use of SC for the purpose of neuroimaging were critically appraised and extracted. Of 16 eligible studies, 6 reported preclinical research and 12 reported clinical experiences encompassing 189 total patients with SC. The cohort age ranged from teens to 80s and was 60% (113/189) female. Sonolucent materials in clinical use are clear PMMA (polymethylmethacrylate), opaque PMMA, polyetheretherketone, and polyolefin. Overall indications included hydrocephalus (20%, 37/189), tumor (15%, 29/189), posterior fossa decompression (14%, 26/189), traumatic brain injury (11%, 20/189), bypass (27%, 52/189), intracerebral hemorrhage (4%, 7/189), ischemic stroke (3%, 5/189), aneurysm and subarachnoid hemorrhage (3%, 5/189), subdural hematoma (2%, 4/189), and vasculitis and other bone revisions (2%, 4/189). Complications described in the entire cohort included revision or delayed scalp healing (3%, 6/189), wound infection (3%, 5/189), epidural hematoma (2%, 3/189), cerebrospinal fluid leaks (1%, 2/189), new seizure (1%, 2/189), and oncologic relapse with subsequent prosthesis removal (<1%, 1/189). Most studies utilized linear or phased array ultrasound transducers at 3-12 MHz. Sources of artifact on sonographic imaging included prosthesis curvature, pneumocephalus, plating system, and dural sealant. Reported findings were mainly qualitative. We, therefore, suggest that future studies should collect quantitative measurement data during transcranioplasty ultrasonography to validate imaging techniques.

Sonolucent cranioplasty: Is therapeutic FUS the next frontier?

Focused ultrasound (FUS) has emerged as a promising area of research in neuro-oncology. Preclinical and clinical investigation has demonstrated the utility of FUS in therapeutic applications including blood brain barrier disruption for therapeutic delivery, and high intensity FUS for tumor ablation. However, FUS as it exists today is relatively invasive as implantable devices are necessary to achieve adequate intracranial penetration. Sonolucent implants, composed of materials permeable to acoustic waves, have been used for cranioplasty and intracranial imaging with ultrasound. Given the overlap in ultrasound parameters with those used for intracranial imaging, and the demonstrated efficacy of sonolucent cranial implants, we believe that therapeutic FUS through sonolucent implants represents a promising avenue of future research. The potential applications of FUS and sonolucent cranial implants may confer the demonstrated therapeutic benefits of existing FUS applications, without the drawbacks and complications of invasive implantable devices. Here we briefly summarize existing evidence regarding sonolucent implants and describe applications for therapeutic FUS.

Ectopic expression of a mechanosensitive channel confers spatiotemporal resolution to ultrasound stimulations of neurons for visual restoration

Remote and precisely controlled activation of the brain is a fundamental challenge in the development of brain-machine interfaces for neurological treatments. Low-frequency ultrasound stimulation can be used to modulate neuronal activity deep in the brain, especially after expressing ultrasound-sensitive proteins. But so far, no study has described an ultrasound-mediated activation strategy whose spatiotemporal resolution and acoustic intensity are compatible with the mandatory needs of brain-machine interfaces, particularly for visual restoration. Here we combined the expression of large-conductance mechanosensitive ion channels with uncustomary high-frequency ultrasonic stimulation to activate retinal or cortical neurons over millisecond durations at a spatiotemporal resolution and acoustic energy deposit compatible with vision restoration. The in vivo sonogenetic activation of the visual cortex generated a behaviour associated with light perception. Our findings demonstrate that sonogenetics can deliver millisecond pattern presentations via an approach less invasive than current brain-machine interfaces for visual restoration.

Establishing proof of concept for sonolucent cranioplasty and point of care ultrasound imaging after posterior fossa decompression for Chiari malformation

BACKGROUND

Evaluation after posterior fossa decompression for Chiari malformation can require repeated imaging, particularly with persistent symptoms. Typically, CT or MRI is used. However, CT carries radiation risk and MRI is costly. Ultrasound is an inexpensive, radiation-free, point-of-care modality that has, thus far, been limited by intact skull and traditional cranioplasty materials. Ultrasound also allows for imaging in different head positions and body postures, which may lend insight into cause for persistent symptoms despite adequate decompression on traditional neutral static CT or MRI. We evaluate safety and feasibility of ultrasound as a post-operative imaging modality in patients reconstructed with sonolucent cranioplasty during posterior fossa decompression for Chiari malformation.

METHODS

Outcomes were analyzed for 26 consecutive patients treated with a Chiari-specific sonolucent cranioplasty. This included infection, need for revision, CSF leak, and pseudomeningocele. Ultrasound was performed point-of-care in the outpatient clinic by the neurosurgery team to assess feasibility.

RESULTS

In eight months mean follow up, there were no surgical site infections or revisions with this novel sonolucent cranioplasty. Posterior fossa anatomy was discernable via transcutaneous ultrasound obtained point-of-care in the clinic setting at follow up visits.

CONCLUSION

We demonstrate proof of concept for ultrasound as a post-operative imaging modality after posterior fossa decompression for Chiari malformation. With further investigation, ultrasound may prove to serve as an alternative to CT and MRI in this patient population, or as an adjunct to provide positional and dynamic information. Use of sonolucent cranioplasty is safe. This technique deserves further study.

Sonolucent Cranioplasty in Extracranial to Intracranial Bypass Surgery: Early Multicenter Experience of 44 Cases

BACKGROUND

The new sonolucent cranioplasty implant (clear polymethyl methacrylate, PMMA) adds functionality besides surgical reconstruction. One possible application uses the transcranioplasty ultrasound (TCUS) technique after PMMA cranioplasty to assess graft patency of extracranial-intracranial (EC-IC) bypass procedures.

OBJECTIVE

To report our early multicenter experience.

METHODS

This is a multicenter analysis of consecutive EC-IC bypass patients from 5 US centers (2019-2022) with closure postbypass using PMMA implant.

RESULTS

Forty-four patients (median age 53 years, 68.2% females) were included. The most common indication for bypass was Moyamoya disease/syndrome (77.3%), and superficial temporal artery to middle cerebral artery bypass was the most common procedure (79.5%). Pretreatment modified Rankin Scales of 0 and 1 to 2 were noted in 11.4% and 59.1% of patients, respectively. Intraoperative imaging for bypass patency involved a combination of modalities; Doppler was the most used modality (90.9%) followed by indocyanine green and catheter angiography (86.4% and 61.4%, respectively). Qualitative TCUS assessment of graft patency was feasible in all cases. Postoperative inpatient TCUS confirmation of bypass patency was recorded in 56.8% of the cases, and outpatient TCUS surveillance was recorded in 47.7%. There were no cases of bypass failure necessitating retreatment. Similarly, no implant-related complications were encountered in the cohort. Major complications requiring additional surgery occurred in 2 patients (4.6%) including epidural hematoma requiring evacuation (2.3%) and postoperative surgical site infection (2.3%) that was believed to be unrelated to the implant.

CONCLUSION

This multicenter study supports safety and feasibility of using sonolucent PMMA implant in EC-IC bypass surgery with the goal of monitoring bypass patency using TCUS.

First Experience With Postoperative Transcranial Ultrasound Through Sonolucent Burr Hole Covers in Adult Hydrocephalus Patients

BACKGROUND

Managing patients with hydrocephalus and cerebrospinal fluid (CSF) disorders requires repeated head imaging. In adults, it is typically computed tomography (CT) or less commonly magnetic resonance imaging (MRI). However, CT poses cumulative radiation risks and MRI is costly. Ultrasound is a radiation-free, relatively inexpensive, and optionally point-of-care alternative, but is prohibited by very limited windows through an intact skull.

OBJECTIVE

To describe our initial experience with transcutaneous transcranial ultrasound through sonolucent burr hole covers in postoperative hydrocephalus and CSF disorder patients.

METHODS

Using cohort study design, infection and revision rates were compared between patients who underwent sonolucent burr hole cover placement during new ventriculoperitoneal shunt placement and endoscopic third ventriculostomy over the 1-year study time period and controls from the period 1 year before. Postoperatively, trans-burr hole ultrasound was performed in the clinic, at bedside inpatient, and in the radiology suite to assess ventricular anatomy.

RESULTS

Thirty-seven patients with sonolucent burr hole cover were compared with 57 historical control patients. There was no statistically significant difference in infection rates between the sonolucent burr hole cover group (1/37, 2.7%) and the control group (0/57, P = .394). Revision rates were 13.5% vs 15.8% (P = 1.000), but no revisions were related to the burr hole or cranial hardware.

CONCLUSION

Trans-burr hole ultrasound is feasible for gross evaluation of ventricular caliber postoperatively in patients with sonolucent burr hole covers. There was no increase in infection rate or revision rate. This imaging technique may serve as an alternative to CT and MRI in the management of select patients with hydrocephalus and CSF disorders.

Neuroimaging through Sonolucent Cranioplasty: A Systematic Scoping Review Protocol

Cranioplasty is a neurosurgical procedure in which the skull bone is repaired after craniectomy. Recently, studies have suggested that sonolucent synthetic materials are safe and useful for cranioplasty. Sonolucent cranioplasty (SC) implants provide unprecedented opportunity in adult neurosurgery to monitor neuroanatomy, assess hemodynamics, view devices located within the implant, and conduct focused ultrasound treatments. Current research on SC includes proof-of-concept cadaveric studies, patient-related safety and feasibility studies, and case series demonstrating transcranioplasty ultrasonography (TCUS). The purpose of this protocol is to investigate the current literature on SC use and outcomes in TCUS. We will perform a systematic literature search following PRISMA-ScR guidelines. The search will be conducted using Ovid Embase, Ovid Medline, and Web of Science Core Collection databases. Titles, abstracts, and full texts will be screened. Joanna Briggs Institute critical appraisal tools will be utilized. Data extraction points will include subject characteristics, SC implant characteristics, ultrasound characteristics, and sonographic findings. These findings will provide a comprehensive review of the literature on sonolucent cranioplasty and directions for future research.

Bedside Ultrasound for Ventricular Size Monitoring in Patients with PEEK Cranioplasty: A Preliminary Experience of Technical Feasibility in Neurotrauma Setting

BACKGROUND

Posttraumatic hydrocephalus is a known complication after traumatic brain injury, particularly affecting patients undergoing decompressive craniectomy. Posttraumatic hydrocephalus monitoring in these patients represents a common issue in neurosurgical practice. Patients require periodical assessments by means of computed tomography (CT) scans. This study presents a preliminary institutional series in which ultrasound was used as a bedside imaging technique to monitor ventricular size in patients harboring a polyetheretherketone (PEEK) cranioplasty. Exploiting the PEEK cranioplasty permeability to echoes, we evaluated the feasibility of this bedside imaging method in monitoring hydrocephalus evolution, determining effects of ventriculo-peritoneal shunt, and excluding complications.

METHODS

Eight patients with traumatic brain injury harboring PEEK cranioplasty following decompressive craniectomy were prospectively evaluated. Ultrasound measurements were compared with CT scan data taken the same day, and ventricular morphometry parameters were compared.

RESULTS

Ultrasound images through the PEEK cranioplasty were of high quality and intracranial anatomy was distinctly evaluated. A strong correlation was observed between ultrasound and CT measurements. Concerning distance between lateral ventricles frontal horns (IFH) and the diameter of the third ventricle (TV), we found a strong correlation between transcranial sonography and CT measurements in preventriculoperitoneal shunt (rho = 0.92 and p = 0.01 for IFH; rho = 0.99 and p = 0.008 for TV) and in postventriculoperitoneal shunt examinations (rho = 0.95 and p = 0.03 for IFH; rho = 0.97 and p = 0.03 for TV). The mean error rate between transcranial sonography and CT scan was 1.77 ± 0.91 mm for preoperative IFH, 0.65 ± 0.27 mm for preoperative TV, 2.18 ± 0.82 mm for postoperative IFH, and 0.48 ± 0.21 mm for postoperative TV.

CONCLUSIONS

Transcranial ultrasound could represent a simplification of the follow-up and management of ventricular size of patients undergoing PEEK cranioplasty. Even if this is a small series, our preliminary results could widen the potential benefits of PEEK, not only as effective material for cranial reconstruction but also, in selected clinical conditions, as a reliable window to explore intracranial content and to monitor ventricular sizes and shunt functioning.

Ultrasounds induce blood–brain barrier opening across a sonolucent polyolefin plate in an in vitro isolated brain preparation

The blood–brain barrier (BBB) represents a major obstacle to the delivery of drugs to the central nervous system. The combined use of low-intensity pulsed ultrasound waves and intravascular microbubbles (MB) represents a promising solution to this issue, allowing reversible disruption of the barrier. In this study, we evaluate the feasibility of BBB opening through a biocompatible, polyolefin-based plate in an in vitro whole brain model. Twelve in vitro guinea pig brains were employed; brains were insonated using a planar transducer with or without interposing the polyolefin plate during arterial infusion of MB. Circulating MBs were visualized with an ultrasonographic device with a linear probe. BBB permeabilization was assessed by quantifying at confocal microscopy the extravasation of FITC-albumin perfused after each treatment. US-treated brains displayed BBB permeabilization exclusively in the volume under the US beam; no significant differences were observed between brains insonated with or without the polyolefin plate. Control brains not perfused with MB did not show signs of FITC-albumin extravasation. Our preclinical study suggests that polyolefin cranial plate could be implanted as a skull replacement to maintain craniotomic windows and perform post-surgical repeated BBB opening with ultrasound guidance to deliver therapeutic agents to the central nervous system.

Double-barrel STA-MCA bypass for cerebral revascularization: lessons learned from a 10-year experience

OBJECTIVE

In select patients, extracranial-intracranial (EC-IC) bypass remains an important tool for cerebral revascularization. Traditionally, superficial temporal artery-middle cerebral artery (STA-MCA) bypass was performed using one limb of the STA only. In an attempt to augment flow and to direct flow to different ischemic areas of the brain, the authors adopted a "double-barrel" technique in which both branches of the STA are used to revascularize distinct MCA territories.

METHODS

A series of consecutive double-barrel STA-MCA bypasses performed between 2010 and 2020 were reviewed. Each anastomosis was directed to augment flow to a territory most at risk based on preoperative perfusion studies, cerebral angiography, and intraoperative indocyanine green data. CT perfusion and CTA were routinely used to evaluate postoperative augmentation and graft patency. Patient perioperative outcomes, surgical complications, and modified Rankin Scale (mRS) scores at the last follow-up were reported.

RESULTS

Forty-four patients (16 males, 28 females) successfully underwent double-barrel STA-MCA bypass on 54 cerebral hemispheres: 28 operations were for moyamoya disease, 23 for atherosclerotic disease refractory to medical therapy, 2 for complex cerebral aneurysms, and 1 for carotid occlusion as a sequela of cavernous meningioma growth. Ten patients underwent multiple operations, 9 of whom had moyamoya disease/syndrome, with the subsequent operation on the contralateral hemisphere. The average patient age at surgery was 45.1 years (range 14-73 years), with a mean follow-up time of 22.1 months. Intraoperative graft patency was confirmed in 100% of cases, and 101 (98.1%) of the 103 anastomoses with imaging follow-up were patent. Perfusion to the revascularized hemisphere was improved in 88.2% of cases. Perioperative ischemic and hemorrhagic complications occurred in 8 procedures (2 were asymptomatic), whereas remote ischemic and hemorrhagic events occurred in 7 cases. There was no mortality in the series, and the mean patient mRS scores were 1.72 at presentation and 1.15 at the last follow-up.

CONCLUSIONS

The high rates of intraoperative and postoperative patency support the feasibility of dual-anastomosis STA-MCA bypass for revascularization. The perioperative complication rate is not significantly different from that of single-anastomosis bypass. The functional outcomes at follow-up and perfusion improvement postoperatively support the efficacy and safety of this method as a treatment strategy.

Nanoparticle-Mediated Angiotensin-(1-9) Drug Delivery for the Treatment of Cardiac Hypertrophy

Ang-(1-9) peptide is a bioactive vasodilator peptide that prevents cardiomyocyte hypertrophy in vitro and in vivo as well as lowers blood pressure and pathological cardiovascular remodeling; however, it has a reduced half-life in circulation, requiring a suitable carrier for its delivery. In this work, hybrid nanoparticles composed of polymeric nanoparticles (pNPs) based on Eudragit^® E/Alginate (EE/Alg), and gold nanospheres (AuNS), were developed to evaluate their encapsulation capacity and release of Ang-(1-9) under different experimental conditions. Hybrid pNPs were characterized by dynamic light scattering, zeta potential, transmission and scanning electron microscopy, size distribution, and concentration by nanoparticle tracking analysis. Nanometric pNPs, with good polydispersity index and colloidally stable, produced high association efficiency of Ang-(1-9) and controlled release. Finally, the treatment of neonatal cardiomyocytes in culture with EE/Alg/AuNS 2% + Ang-(1-9) 20% pNPs decreased the area and perimeter, demonstrating efficacy in preventing norepinephrine-induced cardiomyocyte hypertrophy. On the other hand, the incorporation of AuNS did not cause negative effects either on the cytotoxicity or on the association capacity of Ang-(1-9), suggesting that the hybrid carrier EE/Alg/AuNS pNPs could be used for the delivery of Ang-(1-9) in the treatment of cardiovascular hypertrophy.