Penelope Mantilla

Dr. Penelope Mantilla

orcid

Research Focus & Metrics

Academic Career Length

3Years (2024-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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10 May 2025 in Biomedicines
Verified
Journal Article
Open access
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JVJose Valerio
Jose Valerio
GVGuillermo de Jesús Aguirre Vera
Guillermo de Jesús Aguirre Vera
JZJorge Zumaeta
Jorge Zumaeta
NRNoe Santiago Rea
Noe Santiago Rea
Maria Paula Fernandez GomezMaria Paula Fernandez Gomez
Maria Paula Fernandez Gomez
Andres Mauricio Alvarez-PinzonAndres Mauricio Alvarez-Pinzon
Andres Mauricio Alvarez-Pinzon
Background: 5-Aminolevulinic acid (5-ALA) serves as a precursor in the heme biosynthesis pathway, resulting in the selective accumulation of protoporphyrin IX (PpIX) within glioma cells. This property facilitates fluorescence-guided resection (FGR) in high-grade gliomas (HGGs), enhancing surgical precision and oncological results. Nonetheless, its clinical implementation is restricted by factors such as accessibility, cost, and technical limitations. Methods: A systematic review of PubMed literature (2019–2024) was conducted to assess the efficacy of 5-ALA in HGG surgery compared to conventional white light microscopy. Studies focusing on non-neurosurgical applications, pediatric populations, and non-HGG indications were excluded. Results: Nineteen articles met the criteria. Recent studies indicate that 5-ALA-guided resection significantly enhances gross total resection (GTR) rates compared to white light surgery (75.4% vs. 54.3%, p < 0.001). Patients receiving 5-ALA-assisted resection exhibit enhanced progression-free survival (PFS) at 6 months (median 8.1 months compared to 5.4 months, p = 0.002) and overall survival (OS) (median 15.2 months versus 12.3 months, p = 0.008). The necessity for specialized neurosurgical microscopes equipped with blue light filters restricts accessibility, especially in low-resource environments. Recent advancements in fluorescence-enhancing technologies, particularly loupe-based systems, have demonstrated increases in fluorescence intensity by up to tenfold through direct emission. Sodium fluorescein, originally designed for ophthalmological use, has been adapted for enhancing contrast in intracranial tumors; however, its non-specific binding to serum albumin restricts its accuracy in glioma resection. Conclusions: Recent publications demonstrate that 5-ALA fluorescence-guided surgery significantly improves gross total resection rates and survival outcomes in patients with high-grade gliomas. Although it offers clinical advantages, cost and equipment constraints continue to pose substantial obstacles to broad implementation. Additional research is required to enhance fluorescence-guided techniques and increase accessibility in resource-constrained environments.

Verified
Journal Article
Open access
PDF file
JVJose Valerio
Jose Valerio
AWAizik L Wolf
Aizik L Wolf
PMPenelope Mantilla
Penelope Mantilla
GVGuillermo de Jesús Aguirre Vera
Guillermo de Jesús Aguirre Vera
Maria Paula Fernandez GomezMaria Paula Fernandez Gomez
Maria Paula Fernandez Gomez
Andres Mauricio Alvarez-PinzonAndres Mauricio Alvarez-Pinzon
Andres Mauricio Alvarez-Pinzon
Background: Gamma Knife Radiosurgery (GKRS), a specific type of Stereotactic Radiosurgery (SRS), has developed as a significant modality in the treatment of glioblastoma, particularly in conjunction with standard chemotherapy. The goal of this study is to evaluate the efficacy of combining GKRS with surgical resection and chemotherapy in enhancing therapeutic effects for glioblastoma patients aged 55 years and older. Methods: This prospective clinical study, conducted in accordance with the STROBE guidelines, involved 49 glioblastoma patients aged 55 years and older, treated between January 2013 and January 2023. Data were collected prospectively, and strict adherence to the STUPP protocol was maintained. Only patients who conformed to the STUPP protocol were included in the analysis. Due to concerns regarding the cognitive impairment associated with conventional radiotherapy, and at the patients’ request, a radiosurgery plan was offered. Radiosurgery was administered for 4–8 weeks following surgical resection. Any patients who had not received previous radiotherapy received open surgical tumor removal, followed by GKRS along with adjuvant chemotherapy. Results: In this prospective clinical study of 49 glioblastoma patients aged 55 years and older, the average lifespan post-histopathological diagnosis was established at 22.3 months (95% CI: 12.0–28.0 months). The median time before disease progression was 14.3 months (95% CI: 13.0–29.7 months). The median duration until the first recurrence after treatment was 15.2 months, with documented cases varying between 4 and 33 months. The Gamma Knife Radiosurgery (GKRS) treatment involved a median marginal recommended dose of 12.5 Gy, targeting an average volume of 5.7 cm3 (range: 1.6–39 cm3). Local recurrence occurred in 21 patients, while distant recurrence was identified in 8 patients. Within the cohort, 34 patients were subjected to further therapeutic approaches, including reoperation, a second GKRS session, the administration of bevacizumab and irinotecan, and PCV chemotherapy. A cognitive function assessment revealed that the patients treated with GKRS experienced significantly less cognitive decline compared to the historical controls, who were treated with conventional radiotherapy. The median MMSE scores declined by 1.9 points over 12 months, and the median MoCA scores declined by 2.9 points. Conclusion: This study demonstrates that Gamma Knife Radiosurgery (GKRS), when integrated with surgical resection and adjuvant chemotherapy, offers a substantial benefit for glioblastoma patients aged 55 years and older. The data reveal that GKRS not only prolongs overall survival and progression-free survival but also significantly reduces cognitive decline compared to conventional radiotherapy. These findings underscore the efficacy and safety of GKRS, advocating for its incorporation into standard treatment protocols for older glioblastoma patients. The potential of GKRS to improve patient outcomes while preserving cognitive function is compelling and warrants further research to optimize and confirm its role in glioblastoma management.

10 June 2025 in NeuroSci
Verified
Journal Article
Open access
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JVJose Valerio
Jose Valerio
IOImmanuel O. Olarinde
Immanuel O. Olarinde
GVGuillermo de Jesús Aguirre Vera
Guillermo de Jesús Aguirre Vera
JZJorge Zumaeta
Jorge Zumaeta
NRNoe Santiago Rea
Noe Santiago Rea
Andres Mauricio Alvarez-PinzonAndres Mauricio Alvarez-Pinzon
Andres Mauricio Alvarez-Pinzon
Background: Disparities in neuro-oncological care between high-income and low- and middle-income countries (LMICs) are well documented, yet region-specific data from Latin America remain limited. This review evaluates epidemiologic trends, access to care, and systemic challenges in brain tumor management across Latin American LMICs, using Argentina as a case study. Methods: A systematic review of peer-reviewed literature was conducted focusing on brain tumor incidence, mortality, risk factors, and availability of diagnostics and treatments in Latin America. Socioeconomic, cultural, and systemic barriers were also analyzed. Results: Latin America exhibits some of the highest global brain tumor mortality rates, with Brazil reporting age-standardized rates exceeding 4.5 per 100,000. Glioblastomas are frequently diagnosed at younger ages, often in the fifth decade of life, compared to the global average. Meningioma incidence has increased by 15–20% over the last decade, yet region-wide data remain fragmented. Access to neuroimaging, neurosurgery, radiotherapy, and chemotherapy is limited, with up to 60% of patients relying solely on under-resourced public health systems. Less than 30% of hospitals in rural areas have MRI availability, and continuous professional training is infrequent. Innovative adaptations, such as awake craniotomy, are used in some LMIC centers in response to equipment scarcity. Conclusions: Brain tumor care in Latin America is hindered by limited epidemiological data, restricted access to diagnostics and treatment, and insufficient workforce training. Targeted investments in healthcare infrastructure, international educational collaborations, and policy-level reforms are critical to reducing disparities and improving outcomes in neuro-oncology across the region.

Verified
Journal Article
Open access
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JVJose Valerio
Jose Valerio
Maria Paula Fernandez GomezMaria Paula Fernandez Gomez
Maria Paula Fernandez Gomez
AAArturo Ayala Arcipreste
Arturo Ayala Arcipreste
NRNoe Santiago Rea
Noe Santiago Rea
PMPenelope Mantilla
Penelope Mantilla
Andres Mauricio Alvarez-PinzonAndres Mauricio Alvarez-Pinzon
Andres Mauricio Alvarez-Pinzon
Introduction: A supraorbital keyhole craniotomy (SOKC) is a novel alternative to frontal craniotomies for accessing the anterior fossa for resecting tumors and clipping aneurysms; however, its implementation is limited in patients at a high risk of complications. We present two cases involving the use of augmented reality (AR) and virtual reality (VR) for patient selection and preoperative planning for a supraorbital tumor resection of anterior fossa meningiomas. Methods: This is a prospective, single-center case series at a research institute. We identified patients with an anterior or middle fossa meningioma regardless of age, gender, and tumor characteristics who could undergo an SOKC and MRI. The preoperative planning was performed with the BrainLab Magic Leap AR/VR platform. The meningiomas were resected through the SOKC under neuronavigation. Results: We identified two cases: a 37-year-old male with a meningioma in the sellar region and an 84-year-old male with a right anterior fossa meningioma, both confirmed by MRI. Both patients had a complete tumor resection by a minimally invasive SOKC after preoperative planning with the AR/VR platform. Postoperatively, hyponatremia complicated the first case, while the second case developed an intracranial hemorrhage. They both recovered after the appropriate interventions. Conclusions: The use of an SOKC for anterior skull base meningiomas should be individualized after considering the lesion characteristics, vascular control needs, and the surgeon’s expertise. VR/AR-assisted preoperative evaluation and planning will optimize the patient selection and surgical outcomes. We can utilize VR/AR technologies to identify patients that will benefit from an SOKC and expand the implementation of the approach beyond its current limitations.

1 April 2024 in Brain and Spine
Verified
Journal Article
Open access
JPJose E. Valerio Pascua
Jose E. Valerio Pascua
PMPenelope Mantilla
Penelope Mantilla
Maria Paula Fernandez GomezMaria Paula Fernandez Gomez
Maria Paula Fernandez Gomez
NRNoe Santiago Rea
Noe Santiago Rea
MBMatteo Borro
Matteo Borro
Andres Mauricio Alvarez-PinzonAndres Mauricio Alvarez-Pinzon
Andres Mauricio Alvarez-Pinzon
Patients with multiple sclerosis (MS) are more likely to develop trigeminal neuralgia (TN) compared to the regular population, due to scarring of the nerve and development of a demyelination plaque. Despite treatment, approximately 10% of MS patients treated for TN experience symptom recurrence, including the development of MS-like symptoms such as optic neuritis and bilateral facial pain. A computed tomography (CT) scan was performed preoperatively on two patients diagnosed with multiple sclerosis (MS) who experienced secondary trigeminal neuralgia (TN). A precise reference frame was strapped firmly to the patient's forehead during the intraoperative procedure. Preliminary CT images were registered using the navigation system and the bony landmarks were set. Two patients diagnosed with multiple sclerosis (MS) who experienced refractory trigeminal neuralgia (TN) underwent percutaneous balloon compression. Initial conservative treatment and one dosage of Gamma Knife Radiosurgery (GKR) resulted in symptom control for a few weeks. Both patients had an acute recurrence of pain; thus, percutaneous retrogasserian balloon compression was performed. During follow-up, the patients reported a 70% decrease in pain after the procedure, with minimal recurrence of shooting episodes. Management of trigeminal neuralgia secondary to drug-resistant multiple sclerosis presents a persistent challenge. The percutaneous technique for retrogasserian balloon compression may offer a solution for some patients, but it presents unique challenges for neurosurgeons. Given the complexity of the pathogenesis, target identification, and the potential absence of neurovascular conflict, microvascular decompression remains a debated approach for this patient population. While stereotactic radiosurgery may be a promising alternative.

1 September 2024 in Revista Argentina de Neurocirugía
Verified
Journal Article
Open access
PDF file
PKPavlos Koseoglou
Pavlos Koseoglou
SGSebastián Alberto Ochoa Guzmán
Sebastián Alberto Ochoa Guzmán
PMPenelope Mantilla
Penelope Mantilla
JVJose Valerio
Jose Valerio
Introducción: las tecnologías de computación espacial se aplican cada vez más en el sistema de salud. Se utilizan como herramientas para la educación médica, la información del paciente, la planificación de cirugías y como asistentes durante los procedimientos quirúrgicos. La realidad mixta permite interactuar entre el mundo virtual y el real y sus funciones aumentan rápidamente. Objetivos: comunicar la utilidad de la realidad mixta en la planificación quirúrgica de los tumores cerebrales. Descripción del caso: paciente de sexo masculino, de 67 años, portador de un meningioma agresivo tratado con varias cirugías previas. Fue internado tras una historia clínica de trastornos cognitivos, alteración de la conducta y empeoramiento progresivo de los déficits neurológicos focales con un mes de evolución. La resonancia magnética mostró un tumor parasagital frontoparieto-temporal (FPT) izquierdo con regiones necróticas y efecto de masa. Se utilizó el visualizador de realidad mixta Brainlab® para la planificación preoperatoria. Intervención: se realizó una resección estereotáctica del tumor cerebral sin marco. La longitud holográfica de los bordes del tumor se comparó con los bordes reales de este, tal como se observa después de la extirpación. Conclusión: la aplicación de realidad mixta en neurocirugía muestra buenos resultados. Aunque los estudios han encontrado una mejora en la experiencia del cirujano en el área prequirúrgica, el uso de esta tecnología en el área intraoperatoria está generando grandes expectativas. Aún es necesario demostrar de manera concreta los beneficios que su empleo le otorga al paciente, lo que representa un aspecto clave a estudiar.