Patient-specific CFD modeling of CSF flow in Chiari I malformation: denticulate-ligament-induced compartmentalization explains flow patterns Guillermo L. Nozaleda, Francisco J. Parras-Martos, Carolyna Yamamoto, Wilfried Coenen, Carlos Martínez-Bazán, Gonzalo Olivares-Granados, Nicolás Cordero-Tous, Vijay M. Ravindra, Cándido Gutiérrez-Montes, Antonio L. Sánchez Fluids and Barriers of the CNS, 2026 Computational fluid dynamics (CFD) has been widely used to study cerebrospinal fluid (CSF) flow in Chiari Malformation Type I (CM-I). However, most approaches rely on limited patient-specific detail, and it remains unclear whether such minimal input is sufficient to yield physiologically realistic flow predictions. In this study, we construct a series of MRI-based models of the craniocervical CSF space in a CM-I patient, complemented with representations of microanatomical features derived from ex vivo measurements and patient MRI data, to assess how CFD predictions are influenced by the choice of boundary conditions in the numerical integrations and the inclusion or omission of nerve roots and denticulate ligaments in the anatomical model. Our results reveal that while increasing patient-specific detail in boundary conditions improves agreement with velocity fields measured via phase-contrast MRI, key flow features—most notably anterior–posterior compartmentalization and bidirectional patterns during flow reversal—only emerge when denticulate ligaments are included in the model. In contrast, inclusion of nerve roots has a more localized effect on the velocity field and a modest impact on pressure drops. Our findings not only clarify how more detailed boundary conditions and improved anatomical fidelity affect velocity and pressure predictions, but also provide a mechanistic explanation for flow patterns commonly observed in CM-I that have remained unexplained, highlighting the critical role of denticulate ligaments.
Advancing Personalized Intrathecal Therapy: A Quasi-Experimental Study for the Evaluation of Patient Satisfaction and Pain in Ultrasound-Guided Versus Template-Guided Refill Techniques Beatriz Lechuga Carrasco, Beatriz Piqueras-Sola, Nicolás Cordero Tous, Jonathan Cortés-Martín, Juan Carlos Sánchez-García, Raquel Rodríguez-Blanque, Rafael Gálvez Mateos Journal of Personalized Medicine, 2026 Background: Traditional refills of intrathecal infusion pumps rely on manual palpation and the use of external templates, a method that can be challenging in patients with anatomical variations or a high body mass index. Ultrasound guidance has emerged as a precision-based alternative. This study aimed to evaluate the impact of the ultrasound-guided technique versus the conventional template-based technique on patient satisfaction. Methods: A quasi-experimental before-and-after study was conducted on a cohort of 45 chronic pain patients. Immediate satisfaction with procedure duration (IPP-SQ), overall treatment efficacy (CRES-4), and pain interference via the Brief Pain Inventory (BPI) were assessed. Results: The use of ultrasound was associated with significantly higher satisfaction regarding procedure duration, with a mean score of 5.00 (95% CI: 4.35–5.65) compared to 3.22 (95% CI: 2.70–3.75) with the traditional method (p < 0.001). Overall satisfaction (CRES-4) also improved significantly (12.4 vs. 11.3; p = 0.001). Regarding patient-reported outcome measures (PROMs), the mean pain intensity in the subsequent week was lower following the ultrasound technique (mean difference −0.48; p = 0.040). Technically, no first-attempt failures were recorded under ultrasound guidance in this sample, compared to a 20% re-attempt rate observed with the manual method. Conclusions: The transition from the traditional method to ultrasound-guided refill optimizes technical precision and substantially enhances the patient experience. By reducing pain and increasing satisfaction, ultrasound guidance proves to be a valuable resource for improving procedural precision, representing an advancement toward a more personalized medicine approach.
Ultrasound-Guided Localization of the Refill Port for Intrathecal Infusion Pump Recharge: A Systematic Review Beatriz Lechuga Carrasco, Nicolás Cordero Tous, Andrés Reinoso-Cobo, Jonathan Cortés-Martín, Juan Carlos Sánchez-García, Raquel Rodríguez-Blanque, Rafael Gálvez Mateos Journal of Clinical Medicine, 2025 Background: Managing pain with intrathecal infusion pumps has significantly improved the treatment of individuals whose pain is uncontrollable by other methods. Using ultrasound to locate the refill port of these infusion pumps may offer an improvement over traditional methods. Objective: The objective of this systematic review is to update existing knowledge on the use of ultrasound for locating the refill port in intrathecal infusion pumps. Methods: The PRISMA review protocol was followed, and the review was registered in PROSPERO under registration number CRD 42024595671. Results: The main findings indicate that this technique is primarily used only in complex cases where access is difficult. Pain assessment, patient satisfaction, and recharge time compared to the traditional method are crucial factors for selecting the type of process to implement. Conclusions: No conclusive data are presented regarding the technique’s effect on pain reduction, patient satisfaction, reduction in time spent refilling the pump, or the prior experience level of the professional performing it, but notable improvements in these aspects are observed in certain situations.
Comparison Between Surgical and Perc utaneous Paddles in Spinal Cord Stimulation for Chronic Neuropathic Pain Marta Antonia Gómez-González, Nicolás Cordero-Tous, Carlos Sánchez-Corral, Beatriz Lechuga-Carrasco, Manuel Alejandro Sánchez-García, Rafael Gálvez-Mateos, Gonzalo Olivares-Granados Journal of Clinical Medicine, 2025 Background: Spinal cord stimulation (SCS) is a well-established treatment for chronic neuropathic pain, offering a safe procedure with low complication rates. Both surgical and percutaneous leads can be effective, with similar complication rates. Methods: We analyzed all patients implanted at a reference center since 1996 to compare pain control and complications and determine whether one system was more effective than the other in patients who had experienced both systems. A retrospective observational study was designed. Results: A total of 188 SCS systems were implanted, with a follow-up period of 79.71 ± 60.39 months (mean ± SD). We analyzed data from 106 males (56.38%) and 82 females (43.62%), ranging from 15 to 76 years old. A total of 68 (36.17%) surgical leads and 120 (63.83%) percutaneous leads were implanted for failed back syndrome (120, 63.83%), complex regional pain syndrome (56, 29.79%), and other conditions (12, 6.38%). No statistically significant differences were found in any variables except for lead migration (p = 0.05). In patients who initially had a percutaneous system and later received a surgical system, we found a statistically significant difference in pain relief percentage (p = 0.03) and a trend toward statistical significance in the PGI-C score (p = 0.08). Conclusions: Both surgical and percutaneous leads have demonstrated similar pain control rates, but percutaneous leads have a higher migration rate. Complications can be minimized by performing the procedure in specialized centers with extensive experience. Further studies comparing both systems should be conducted to determine if one type of lead is superior.
Battery Life of Pulse Generators in Spinal Cord Stimulation: Analysis and Comparison Between Surgical and Percutaneous Leads in Energy Efficiency Marta Antonia Gómez González, Nicolás Cordero Tous, Carlos Sánchez Corral, Beatriz Lechuga Carrasco, Manuel Alejandro Sánchez García, Rafael Gálvez Mateos, Gonzalo Olivares Granados Journal of Clinical Medicine, 2025 Background: Spinal cord stimulation (SCS) is an established therapy for chronic neuropathic pain. Although rechargeable and non-rechargeable pulse generators (PGs) are widely used, their real-world battery life and the influence of lead type on energy efficiency remain underexplored. Objective: To evaluate PG battery longevity and compare the performance of surgical versus percutaneous leads in terms of energy efficiency. Methods: We conducted a retrospective study of 283 PGs implanted at Hospital Virgen de las Nieves (Granada, Spain) from 1996 to 2023. Data on patient demographics, pain etiology, lead type and placement, stimulation modality, and PG status were extracted. A competing risks analysis was used to assess PG shutdown and early explantation over time. Results: Of the PGs analyzed, 43.5% were non-rechargeable and 56.5% rechargeable. Rechargeable PGs showed significantly longer battery life (mean: 82.7 vs. 38.9 months, p < 0.05), with a lower probability of shutdown at 50, 100, and 150 months. No significant differences in battery longevity were observed regarding lead location, stimulation type, or pain etiology. A trend toward longer battery life was observed with percutaneous leads, although not statistically significant. Conclusions: Rechargeable PGs demonstrated superior longevity compared to non-rechargeable models and should be considered the preferred option in most cases. While both surgical and percutaneous leads are effective, percutaneous systems may offer improved battery efficiency. Further prospective studies are warranted to confirm these findings and assess cost-effectiveness.
Multidimensional Analysis of Quality of Life in Patients with Chronic Non-Cancer Pain and Short- and Long-Term Intrathecal Analgesic Therapy Manuel Alejandro Sánchez-García, Bernardino Alcázar-Navarrete, Manuel Cortiñas-Saenz, Nicolás Cordero Tous, Rafael Gálvez Mateos Healthcare Switzerland, 2024 Background: Intrathecal drug delivery (IDD) is part of the fourth analgesic step. Evidence on the quality of life of patients with refractory chronic non-cancer pain (CNCP) using these devices and their long-term outcomes is scarce. This study aims to evaluate patients with IDD to assess their HRQoL. Additionally, the study seeks to understand the patients’ satisfaction with the treatment and changes in pain magnitude over time. Methods: Adult patients with CNCP and intrathecal drug delivery systems (IDDS) were included. The study population was divided into two groups: less than and more than 15 years of treatment. HRQoL was analyzed using validated questionnaires. Pain reduction was assessed using the visual analog scale (VAS), and treatment satisfaction was evaluated using the Patient Global Impression of Improvement scale. Results: The results indicate a poor HRQoL in IDD patients, with better scores in the group with ≥15 years of treatment. Pain reduction was similar in both groups, and patients reported a positive satisfaction level with the treatment. Conclusions: HRQoL in CNCP patients is severely affected. Long-term IDD patients have a similar or even better HRQoL in some respects compared to those with shorter follow-ups. IDD patients experienced pain reduction, with most feeling better or much better.
Spinal cord stimulation in refractory complex regional pain syndrome. A prospective study David Suárez Villanueva, Nicolás Cordero Tous, Carmen Paul Ríos, Carlos Sánchez Corral, Isabel Ortiz García, Majed Jouma Katati, Rafael Gálvez Mateos, Gonzalo Olivares Granados Revista De Neurologia, 2024 Introducción y objetivos. En el tratamiento del síndrome de dolor regional complejo se pretende aliviar el dolor y restaurar la función de la extremidad afectada. El objetivo de este estudio es evaluar la estimulación de la médula espinal como terapia para pacientes a quienes se les diagnosticó síndrome de dolor regional complejo, en los que no se ha podido conseguir un control adecuado del dolor con otros tratamientos previos. Pacientes y métodos. Se realizó un estudio prospectivo de 2018 a 2020. Se incluyó a pacientes diagnosticados de síndrome de dolor regional complejo refractario a otros tratamientos o técnicas, clasificados por datos demográficos. Posteriormente, se hizo seguimiento de la eficacia, la funcionalidad y la dependencia de opioides de cada paciente durante un año. Resultados. Siete de los 13 (53,84%) pacientes incluidos en el estudio consiguieron un alivio significativo de su dolor con la estimulación medular. Se obtuvo mejoría del dolor y de la funcionalidad, y ambas fueron estadísticamente significativas (p < 0,001 y p = 0,003, respectivamente). La mejoría en el Oswestry Disability Index/Neck Disability Index (ODI/NDI) se asoció significativamente con el índice de masa corporal (IMC) (p = 0,011) y fue menor cuanto mayor era el IMC. Conclusiones. Los resultados sugieren que la estimulación de la médula espinal es una opción terapéutica eficaz para pacientes con SDRC refractario a otros tratamientos. Además, el IMC y el ODI/NDI mostraron una correlación significativa.
[18F]Fluorocholine PET/CT false positive: foreign body reaction mimicking anaplastic glioma progression. A case report Teodoro Rudolphi-Solero, Eva María Triviño-Ibáñez, José Pablo Martínez-Barbero, Nicolás Cordero-Tous, Clara Eugenia Chamorro-Santos, Antonio Rodríguez-Fernández, Manuel María Gómez-Río Egyptian Journal of Neurology Psychiatry and Neurosurgery, 2023 Background Foreign body reaction in brain tissue is a very rare immune response that has not been well studied. Hemostatic material has been reported as a possible trigger of this response in other organs and could be detected by [18F]fluorodeoxyglucose positron emission tomography/computerized tomography ([18F]FDG PET/CT), but there is no reported experience about the role of [18F]fluorocholine in this finding. [18F]Fluorocholine has the potential to differentiate viable central nervous system tumors from other entities, so it is frequently used in the follow-up of neurosurgery patients. Case presentation A right frontoparietal neoplastic lesion was found in a young-aged patient with analgesic refractory headache. Surgical resection and postsurgical radiotherapy were performed, and the pathologist analysis turned out a cellular ependymoma with signs of anaplasia. In the follow-up, an magnetic resonance imaging (MRI) showed a suspicious lesion, so a [18F]fluorocholine PET/CT was performed. Increased uptake was described in the right parietal region on the margin of the residual cystic lesion. The patient got a complete resection which was confirmed later by MRI. In the pathology analysis, a focally congestive cerebral parenchyma with a central histiocytic reaction to a foreign body area was described. Conclusions Following the experience of the current case report, [18F]fluorocholine PET/CT could also show a false positive related to foreign body reaction. This entity should be considered to avoid unnecessary major surgery on our patients.
