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2.
Oper Neurosurg (Hagerstown) ; 27(4): 449-454, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39283099

RESUMEN

BACKGROUND AND OBJECTIVES: 3-Dimensional (3D) printing has become a common tool to aid implant molding for cranioplastic surgery of large skull defects. Until now, 3D printing of cranial implants itself has not been used, mainly because of medicolegal concerns. With a 3D printer developed for printing medical applications and with implant-grade polyetheretherketone (PEEK) filament available, we established a workflow (in compliance with medical device regulations) to 3D print cranial implants for cranioplastic surgery directly at the point of care (POC). Here, we describe the implementation of 3D printing these PEEK implants for cranioplastic surgery at our academic hospital. METHODS: A thorough design and 3D printing process, in accordance with local medical device regulations, was developed. Implants are digitally designed based upon pre- and post-craniectomy cranial computed tomography scans by trained 3D printing experts from the department of medical engineering at our institution. Implants are then produced on a medical 3D printer with implant-grade PEEK filament using the fused filament fabrication process. After postprocessing and steam sterilization, implantation for reconstruction of the skull can be performed. RESULTS: Cranioplastic surgery with a 3D-printed PEEK implant was performed at our institution in a patient with a large frontotemporoparietal skull defect after traumatic brain injury with consecutive decompressive craniectomy. No intra- or post-operative complications occurred. Postoperative cranial computed tomography scans showed perfect reconstruction of precraniectomy skull shape. The aesthetic result was promising and satisfactory to the patient. CONCLUSION: This novel 3D printing workflow enables the production of patient-specific cranial implants from PEEK, to reconstruct large skull defects directly at the POC in accordance with the European Medical Device Regulation. This marks an unprecedented technological and legal advancement, enabling the hospital infrastructure not only to deliver the cranioplastic surgery itself, but also additive manufacturing of the implant directly at the POC.


Asunto(s)
Benzofenonas , Cetonas , Sistemas de Atención de Punto , Polietilenglicoles , Polímeros , Impresión Tridimensional , Cráneo , Humanos , Cráneo/cirugía , Prótesis e Implantes , Procedimientos de Cirugía Plástica/métodos , Procedimientos de Cirugía Plástica/instrumentación , Diseño de Prótesis
3.
PLoS One ; 19(9): e0309646, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39264942

RESUMEN

OBJECTIVE: This study aimed to evaluate the safety and efficacy of skull-femoral traction followed by osteotomy correction in patients with severe spinal scoliosis and split cord malformation. METHODS: We retrospectively analyzed ten cases of severe spinal scoliosis with Pang I type split cord malformation treated between August 2012 and August 2023. Patients underwent skull-femoral traction prior to osteotomy correction. We assessed changes in height, weight, coronal and sagittal Cobb's angles, and physiological indicators such as vital capacity (VC), forced vital capacity (FVC), forced expiratory volume in one second (FEV1), and blood gas levels before, during, and after treatment. RESULTS: Traction duration ranged from 9 to 19 days, with height and weight showing significant increases post-treatment. The coronal Cobb's angle improved from pre-treatment to post-corrective surgery and remained stable at the final follow-up. Similar improvements were observed in the sagittal plane. Physiological indicators such as VC, FVC, and FEV1, as well as blood gas levels, normalized after treatment. Nutritional status, indicated by triceps skinfold thickness, albumin, and transferrin concentrations, also improved. No neurological complications or device-related complications occurred during or after treatment. CONCLUSION: Skull-femoral traction followed by osteotomy correction is a safe and effective treatment for severe spinal scoliosis with split cord malformation, offering an alternative to high-risk procedures.


Asunto(s)
Osteotomía , Escoliosis , Cráneo , Tracción , Humanos , Femenino , Escoliosis/cirugía , Osteotomía/métodos , Masculino , Tracción/métodos , Niño , Adolescente , Estudios Retrospectivos , Cráneo/cirugía , Cráneo/anomalías , Resultado del Tratamiento , Fémur/cirugía , Fémur/anomalías
4.
Neurosurg Focus ; 57(3): E4, 2024 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-39217631

RESUMEN

OBJECTIVE: MR-guided focused ultrasound (MRgFUS) thalamotomy is an incisionless neurosurgical treatment for patients with medically refractory essential tremor and tremor-dominant Parkinson's disease. A low skull density ratio (SDR) < 0.40 is a known risk factor for treatment failure. The aim of this study was to identify useful sonication strategies for patients with a low SDR < 0.40 by modifying the standard sonication protocol using maximum high-energy sonication while minimizing the number of sonications. METHODS: The authors retrospectively analyzed the effects of modified MRgFUS sonication on low-SDR tremor patients. All patients underwent head CT scans to calculate their SDR. The SDR threshold for MRgFUS thalamotomy was 0.35. The patients in the early series underwent the standard sonication protocol targeting the ventral intermediate nucleus contralateral to the treated hand side. The patients with a low SDR < 0.40 in the late series underwent a modified sonication protocol, in which the number of alignment sonications was minimized and high-energy treatment sonication (> 36,000 J) was used. The authors evaluated the lesion volume the following day and tremor improvement and adverse events 3 and 12 months after the procedure. The sonication patterns between low-SDR patients treated using different sonication protocols were examined using Fisher's exact test. ANOVA was used to examine the lesion volume and tremor improvement in high- and low-SDR patients treated using different sonication protocols. RESULTS: Among 41 patients with an SDR < 0.40, 14 underwent standard sonication and 27 underwent modified sonication. Fewer alignment sonications and high-energy treatment sonications were used in the modified sonication group compared with the standard group (p < 0.001). The duration of modified sonication was significantly shorter than that of standard sonication (p < 0.001). The lesion volume and tremor improvement significantly differed among the high- and low-SDR groups with different sonication protocols (p < 0.001). Low-SDR patients treated using modified sonication protocols had comparable lesion volume and tremor improvement to the high-SDR group. The modified sonication protocol did not significantly increase adverse intraprocedural and postprocedural events. CONCLUSIONS: Minimizing alignment sonications and applying high-energy sonication in early treatment help to create an optimal lesion volume and control tremor in low-SDR patients.


Asunto(s)
Temblor Esencial , Enfermedad de Parkinson , Tálamo , Humanos , Temblor Esencial/cirugía , Temblor Esencial/diagnóstico por imagen , Enfermedad de Parkinson/cirugía , Enfermedad de Parkinson/diagnóstico por imagen , Enfermedad de Parkinson/terapia , Femenino , Masculino , Anciano , Persona de Mediana Edad , Estudios Retrospectivos , Tálamo/cirugía , Tálamo/diagnóstico por imagen , Cráneo/cirugía , Cráneo/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Resultado del Tratamiento , Anciano de 80 o más Años , Ultrasonido Enfocado de Alta Intensidad de Ablación/métodos , Sonicación/métodos , Procedimientos Neuroquirúrgicos/métodos
5.
Neurosurg Rev ; 47(1): 616, 2024 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-39271618

RESUMEN

Cranioplasty is a reconstructive neurosurgical procedure that fixes the cranial bone defects after the craniotomy for brain surgeries like tumours, aneurysms, arterio-venous malformations, subdural empyemas and hematomas. Personalized 3D-printed implants offer various advantages, including anatomical accuracy, functional restoration, time-sparing surgery, excellent cosmetic outcomes through their impeccable adjustment to cranial vault defects, and better clinical outcomes. PEEK has a meritorious profile in terms of high success rate, low complication rate, fracture resistance and low toxicity profile, high strength, high toughness, and excellent biocompatibility in cranioplasty. On the other hand, the need for more cost-effective yet ideal biomaterials must be met for nations and patients with financial constraints. Nevertheless, this additively manufactured 3D-printed cranial implant marks the dawn of a new era in precision and personalized neurosurgery.


Asunto(s)
Benzofenonas , Procedimientos Neuroquirúrgicos , Polímeros , Impresión Tridimensional , Prótesis e Implantes , Cráneo , Humanos , Cráneo/cirugía , Procedimientos Neuroquirúrgicos/métodos , Cetonas , Procedimientos de Cirugía Plástica/métodos , Medicina de Precisión/métodos , Materiales Biocompatibles , Craneotomía/métodos , Polietilenglicoles , Neurocirugia
6.
Sci Rep ; 14(1): 19810, 2024 08 27.
Artículo en Inglés | MEDLINE | ID: mdl-39191797

RESUMEN

In this paper, we investigate the effectiveness of shape completion neural networks as clinical aids in maxillofacial surgery planning. We present a pipeline to apply shape completion networks to automatically reconstruct complete eumorphic 3D meshes starting from a partial input mesh, easily obtained from CT data routinely acquired for surgery planning. Most of the existing works introduced solutions to aid the design of implants for cranioplasty, i.e. all the defects are located in the neurocranium. In this work, we focus on reconstructing defects localized on both neurocranium and splanchnocranium. To this end, we introduce a new dataset, specifically designed for this task, derived from publicly available CT scans and subjected to a comprehensive pre-processing procedure. All the scans in the dataset have been manually cleaned and aligned to a common reference system. In addition, we devised a pre-processing stage to automatically extract point clouds from the scans and enrich them with virtual defects. We experimentally compare several state-of-the-art point cloud completion networks and identify the two most promising models. Finally, expert surgeons evaluated the best-performing network on a clinical case. Our results show how casting the creation of personalized implants as a problem of shape completion is a promising approach for automatizing this complex task.


Asunto(s)
Redes Neurales de la Computación , Tomografía Computarizada por Rayos X , Humanos , Imagenología Tridimensional/métodos , Cráneo/diagnóstico por imagen , Cráneo/cirugía , Medicina de Precisión/métodos , Cirugía Bucal/métodos , Cirugía Asistida por Computador/métodos
7.
Med Eng Phys ; 130: 104215, 2024 08.
Artículo en Inglés | MEDLINE | ID: mdl-39160013

RESUMEN

Cranioplasty is the surgical repair of a bone defect in the skull resulting from a previous operation or injury, which involves lifting the scalp and restoring the contour of the skull with a graft made from material that is reconstructed from scans of the patient's own skull. The paper introduces a 3D printing technology in creating molds, which are filled with polymethyl methacrylate (PMMA) to reconstruct the missing bone part of the skull. The procedure included several steps to create a 3D model in an STL format, conversion into a G-code which is further used to produce the mold itself using a 3D printer. The paper presents our initial experience with 5 patients who undergone cranioplasty utilizing 3D printed molds. Making a patient-specific model is a very complex process and consists of several steps. The creation of a patient-specific 3D model loading of DICOM images obtained by CT scanning, followed by thresholding-based segmentation and generation of a precise 3D model of part of the patient's skull. Next step is creating the G-code models for 3D printing, after which the actual models are printed using Fused Deposition Modeling printer and PLA material. All surgeries showed good match of the missing bone part and part created using 3D printed mold, without additional steps in refinement. In such a way, 3D printing technology helps in creating personalized and visually appealing bone replacements, at a low cost of the final product.


Asunto(s)
Procedimientos de Cirugía Plástica , Impresión Tridimensional , Cráneo , Humanos , Cráneo/cirugía , Cráneo/diagnóstico por imagen , Procedimientos de Cirugía Plástica/instrumentación , Procedimientos de Cirugía Plástica/métodos , Polimetil Metacrilato , Tomografía Computarizada por Rayos X , Medicina de Precisión , Masculino
8.
BMC Oral Health ; 24(1): 994, 2024 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-39182066

RESUMEN

BACKGROUND: Bone loss of residual alveolar ridges is a great challenge in the field of dental implantology. Deproteinized bovine bone mineral (DBBM) is commonly used for bone regeneration, however, it is loose and difficult to handle in clinical practice. Hyaluronic acid (HA) shows viscoelasticity, permeability and excellent biocompatibility. The aim of this study is to evaluate whether high-molecular-weight (MW) HA combined with DBBM could promote new bone formation in rat calvarial critical size defects (CSDs). MATERIALS AND METHODS: Rat calvarial CSDs (5 mm in diameter) were created. Rats (n = 45) were randomly divided into 3 groups: HA-DBBM compound grafting group, DBBM particles only grafting group and no graft group. Defect healing was assessed by hematoxylin-eosin staining and histomorphometry 2, 4 and 8 weeks postop, followed by Micro-CT scanning 8 weeks postop. Statistical analyses were performed by ANOVA followed by Tukey's post hoc test with P < 0.05 indicating statistical significance. RESULTS: All rats survived after surgery. Histomorphometric evaluation revealed that at 2, 4 and 8 weeks postop, the percentage of newly formed bone was significantly greater in HA-DBBM compound grafting group than in the other two groups. Consistently, Micro-CT assessment revealed significantly more trabecular bone (BV/TV and Tb.N) in HA-DBBM compound group than in the other two groups, respectively (P < 0.05). Moreover, the trabecular bone was significantly more continuous (Tb.Pf) in HA-DBBM compound group than in the other two groups, respectively (P < 0.05). CONCLUSION: HA not only significantly promoted new bone formation in rats calvarial CSDs but also improved the handling ability of DBBM.


Asunto(s)
Regeneración Ósea , Sustitutos de Huesos , Ácido Hialurónico , Osteogénesis , Cráneo , Microtomografía por Rayos X , Animales , Ácido Hialurónico/farmacología , Ácido Hialurónico/uso terapéutico , Ratas , Cráneo/cirugía , Cráneo/diagnóstico por imagen , Cráneo/patología , Sustitutos de Huesos/uso terapéutico , Sustitutos de Huesos/farmacología , Osteogénesis/efectos de los fármacos , Regeneración Ósea/efectos de los fármacos , Masculino , Ratas Sprague-Dawley , Distribución Aleatoria , Bovinos
9.
J Plast Reconstr Aesthet Surg ; 97: 275-281, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39178692

RESUMEN

OBJECTIVE: Compare full-thickness skin grafts versus split-thickness skin grafts in scalp reconstruction. STUDY DESIGN: Retrospective chart review of patients who underwent scalp reconstruction with skin grafts performed at a single institution from 2011 to 2016. METHODS: χ2 or Fisher exact tests were used to compare graft integration and complication rates. The effects of graft type, defect type, graft size, and patient comorbidities on the likelihood of graft success and complications were analyzed using multivariate logistic regression. RESULTS: A hundred and twenty-five full-thickness and 93 split-thickness grafts were performed in 200 patients, including 68 defects (31.2%) with exposed calvarium. Full-thickness grafts required fewer average reconstructions (P = 0.002). A 92.8% of full-thickness grafts had complete graft integration compared with 78.5% of split-thickness grafts (P = 0.002). This difference was more evident in defects with exposed calvarium (87.2% vs. 47.6%, P ≤ 0.001). Despite higher rates of minor debridement, full-thickness grafts had less postoperative bone exposure and wound breakdown than split-thickness grafts on intact pericranium and exposed calvarium defects. Preoperative radiation, immunosuppression, and increased graft sizes were significant predictors of graft outcomes. CONCLUSIONS: Skin grafts, especially full-thickness, provide a versatile, reliable, and simple approach for reconstructing medium to large scalp defects in the appropriate patient. Even on defects with bare calvarium, full-thickness grafts can succeed when a vascularized recipient bed is prepared. Defects with exposed bone, larger graft sizes, preoperative radiation, and immunosuppression may result in decreased graft take and increased complications. LEVEL OF EVIDENCE: 3b.


Asunto(s)
Procedimientos de Cirugía Plástica , Cuero Cabelludo , Trasplante de Piel , Cráneo , Humanos , Cuero Cabelludo/cirugía , Trasplante de Piel/métodos , Trasplante de Piel/efectos adversos , Masculino , Estudios Retrospectivos , Femenino , Anciano , Persona de Mediana Edad , Procedimientos de Cirugía Plástica/métodos , Procedimientos de Cirugía Plástica/efectos adversos , Cráneo/cirugía , Cráneo/trasplante , Adulto , Complicaciones Posoperatorias/cirugía , Complicaciones Posoperatorias/etiología , Supervivencia de Injerto , Anciano de 80 o más Años
10.
Acta Neurochir (Wien) ; 166(1): 330, 2024 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-39158614

RESUMEN

PURPOSE: Decompressive craniectomy is occasionally performed as a life-saving neurosurgical intervention in patients with acute severe brain injury to reduce refractory intracranial hypertension. Subsequently, cranioplasty (CP) is performed to repair the skull defect. In the meantime, patients are living without cranial bone protection, and little is known about their daily life. This study accordingly explored daily life among patients living without cranial bone protection after decompressive craniectomy while awaiting CP. METHODS: A multiple-case study examined six purposively sampled patients, patients' family members, and healthcare staff. The participants were interviewed and the data were analyzed using qualitative content analysis. RESULTS: The cross-case analysis identified five categories: "Adapting to new ways of living," "Constant awareness of the absence of cranial bone protection," "Managing daily life requires available staff with adequate qualifications," "Impact of daily life depends on the degree of recovery," and "Daily life stuck in limbo while awaiting cranioplasty." The patients living without cranial bone protection coped with daily life by developing new habits and routines, but the absence of cranial bone protection also entailed inconveniences and limitations, particularly among the patients with greater independence in their everyday living. Time spent awaiting CP was experienced as being in limbo, and uncertainty regarding planning was perceived as frustrating. CONCLUSION: The results indicate a vulnerable group of patients with brain damage and communication impairments struggling to find new routines during a waiting period experienced as being in limbo. Making this period safe and reducing some problems in daily life for those living without cranial bone protection calls for a person-centered approach to care involving providing contact information for the correct healthcare institution and individually planned scheduling for CP.


Asunto(s)
Craniectomía Descompresiva , Investigación Cualitativa , Cráneo , Humanos , Masculino , Craniectomía Descompresiva/métodos , Femenino , Adulto , Persona de Mediana Edad , Cráneo/cirugía , Actividades Cotidianas , Procedimientos de Cirugía Plástica/métodos , Anciano , Lesiones Encefálicas/cirugía , Hipertensión Intracraneal/cirugía , Hipertensión Intracraneal/prevención & control
12.
J Vis Exp ; (209)2024 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-39141553

RESUMEN

Mounting evidence indicates that the immune response triggered by brain disorders (e.g., brain ischemia and autoimmune encephalomyelitis) occurs not only in the brain, but also in the skull. A key step toward analyzing changes in immune cell populations in both the brain and skull bone marrow after brain damage (e.g., stroke) is to obtain sufficient numbers of high-quality immune cells for downstream analyses. Here, two optimized protocols are provided for isolating immune cells from the brain and skull bone marrow. The advantages of both protocols are reflected in their simplicity, speed, and efficacy in yielding a large quantity of viable immune cells. These cells may be suitable for a range of downstream applications, such as cell sorting, flow cytometry, and transcriptomic analysis. To demonstrate the effectiveness of the protocols, immunophenotyping experiments were performed on stroke brains and normal brain skull bone marrow using flow cytometry analysis, and the results aligned with findings from published studies.


Asunto(s)
Encéfalo , Citometría de Flujo , Cráneo , Animales , Ratones , Encéfalo/citología , Encéfalo/inmunología , Cráneo/citología , Cráneo/cirugía , Citometría de Flujo/métodos , Células de la Médula Ósea/citología , Células de la Médula Ósea/inmunología , Accidente Cerebrovascular/inmunología , Inmunofenotipificación/métodos
13.
J Mater Sci Mater Med ; 35(1): 50, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39136804

RESUMEN

The human head can sometimes experience impact loads that result in skull fractures or other injuries, leading to the need for a craniectomy. Cranioplasty is a procedure that involves replacing the removed portion with either autologous bone or alloplastic material. While titanium has traditionally been the preferred material for cranial implants due to its excellent properties and biocompatibility, its limitations have prompted the search for alternative materials. This research aimed to explore alternative materials to titanium for cranial implants in order to address the limitations of titanium implants and improve the performance of the cranioplasty process. A 3D model of a defective skull was reconstructed with a cranial implant, and the implant was simulated using various stiff and soft materials (such as alumina, zirconia, hydroxyapatite, zirconia-reinforced PMMA, and PMMA) as alternatives to titanium under 2000N impact forces. Alumina and zirconia implants were found to reduce stresses and strains on the skull and brain compared to titanium implants. However, PMMA implants showed potential for causing skull damage under current loading conditions. Additionally, PMMA and hydroxyapatite implants were prone to fracture. Despite these findings, none of the implants exceeded the limits for tensile and compressive stresses and strains on the brain. Zirconia-reinforced PMMA implants were also shown to reduce stresses and strains on the skull and brain compared to PMMA implants. Alumina and zirconia show promise as alternatives to titanium for the production of cranial implants. The use of alternative implant materials to titanium has the potential to enhance the success of cranial reconstruction by overcoming the limitations associated with titanium implants.


Asunto(s)
Materiales Biocompatibles , Análisis de Elementos Finitos , Ensayo de Materiales , Procedimientos de Cirugía Plástica , Cráneo , Estrés Mecánico , Titanio , Circonio , Humanos , Cráneo/cirugía , Titanio/química , Materiales Biocompatibles/química , Circonio/química , Procedimientos de Cirugía Plástica/métodos , Prótesis e Implantes , Durapatita/química , Polimetil Metacrilato/química , Óxido de Aluminio/química , Resistencia a la Tracción , Fracturas Craneales/cirugía , Fuerza Compresiva
14.
World Neurosurg ; 189: e725-e731, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38964459

RESUMEN

BACKGROUND: Flat head syndrome (FHS) sometimes occurs when a baby maintains the same head position during the first several months of life, causing a skull deformity. FHS usually improves with time and natural growth, although some show aggravation against conservative treatment. We reviewed pathologically proved early closure of skull suture that may be seen secondary to FHS. METHODS: The clinical and radiologic findings of the patients who showed progressive skull deformity resembling FHS were retrospectively reviewed. All the patients underwent surgical treatment and pathologic specimens were obtained. RESULTS: The detected patients included two 5-month-old infants and one 1-year-old child. The former were conservatively treated without any obvious premature suture closure on computed tomography (CT), and later developed progressive tower-like skull deformities. The infants were diagnosed with possible premature fusion of lambda site and underwent removal around lambda depression (LD). The latter showed evident sagittal suture closure on CT with digital markings, and was diagnosed with increased intracranial pressure and underwent cranioplasty of posterior expansion. Histopathologic specimens obtained from the patients' resected sutures showed irregularly narrowed suture structure with ossification and fibrous tissue proliferation within them, supporting the diagnosis of premature closure of the sagittal sutures. Their postoperative courses were uneventful, and their skull deformities subsequently improved. CONCLUSIONS: Conservative therapy-resistant progressive occipital skull deformity with LD may be a sign of early suture closure, even if CT does not show obvious suture closure. The findings are helpful for early diagnosis and might lead to minimal invasive surgery if needed.


Asunto(s)
Suturas Craneales , Humanos , Lactante , Suturas Craneales/cirugía , Suturas Craneales/diagnóstico por imagen , Masculino , Femenino , Estudios Retrospectivos , Tomografía Computarizada por Rayos X , Craneosinostosis/cirugía , Craneosinostosis/complicaciones , Cráneo/cirugía
15.
Neuron ; 112(17): 2869-2885.e8, 2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-38996587

RESUMEN

To understand the neural basis of behavior, it is essential to measure spiking dynamics across many interacting brain regions. Although new technologies, such as Neuropixels probes, facilitate multi-regional recordings, significant surgical and procedural hurdles remain for these experiments to achieve their full potential. Here, we describe skull-shaped hemispheric implants enabling large-scale electrophysiology datasets (SHIELD). These 3D-printed skull-replacement implants feature customizable insertion holes, allowing dozens of cortical and subcortical structures to be recorded in a single mouse using repeated multi-probe insertions over many days. We demonstrate the procedure's high success rate, biocompatibility, lack of adverse effects on behavior, and compatibility with imaging and optogenetics. To showcase SHIELD's scientific utility, we use multi-probe recordings to reveal novel insights into how alpha rhythms organize spiking activity across visual and sensorimotor networks. Overall, this method enables powerful, large-scale electrophysiological experiments for the study of distributed neural computation.


Asunto(s)
Encéfalo , Cráneo , Animales , Ratones , Encéfalo/fisiología , Cráneo/cirugía , Optogenética/métodos , Fenómenos Electrofisiológicos/fisiología , Impresión Tridimensional , Potenciales de Acción/fisiología , Electrodos Implantados , Ratones Endogámicos C57BL , Masculino , Electrofisiología/métodos
16.
Bull Exp Biol Med ; 177(1): 155-161, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38963597

RESUMEN

Experimental model of resection craniotomy with subsequent reconstruction of the defect with a polymer implant enables comprehensive assessment of functional and ultrastructural changes during replacement of the damaged tissue. Reconstruction of a skull defect was accompanied by transient motor disturbance in the acute period and did not cause functional disorders and neurological deficits in a delayed period. Histological examination of osteal and brain tissue revealed no pathological reactions that could be associated with the response to the chemical components of the implant.


Asunto(s)
Benzofenonas , Craneotomía , Polietilenglicoles , Polímeros , Cráneo , Polímeros/química , Animales , Cráneo/cirugía , Cráneo/lesiones , Cráneo/diagnóstico por imagen , Polietilenglicoles/química , Craneotomía/métodos , Ratas , Masculino , Procedimientos de Cirugía Plástica/métodos , Cetonas/química , Materiales Biocompatibles/química , Encéfalo/cirugía , Ratas Wistar
17.
Neurosurg Rev ; 47(1): 331, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39008189

RESUMEN

To determine a rapid and accurate method for locating the keypoint and "keyhole" in the suboccipital retrosigmoid keyhole approach. (1) Twelve adult skull specimens were selected to locate the anatomical landmarks on the external surface of the skull.The line between the infraorbital margin and superior margin of the external acoustic meatus was named the baseline. A coordinate system was established using the baseline and its perpendicular line through the top point of diagastric groove.The perpendicular distance (x), and the horizontal distance (y) between the central point of the "keyhole" and the top point of the digastric groove in that coordinate system were measured. The method was applied to fresh cadaveric specimens and 53 clinical cases to evaluate its application value. (1) x and y were 14.20 ± 2.63 mm and 6.54 ± 1.83 mm, respectively (left) and 14.95 ± 2.53 mm and 6.65 ± 1.61 mm, respectively (right). There was no significant difference between the left and right sides of the skull (P > 0.05). (2) The operative area was satisfactorily exposed in the fresh cadaveric specimens, and no venous sinus injury was observed. (3) In clinical practice, drilling did not cause injury to venous sinuses, the mean diameter of the bone windows was 2.0-2.5 cm, the mean craniotomy time was 26.01 ± 3.46 min, and the transverse and sigmoid sinuses of 47 patients were well-exposed. We propose a "one point, two lines, and two distances" for "keyhole" localization theory, that is we use the baseline between the infraorbital margin and superior margin of the external acoustic meatus and the perpendicular line to the baseline through the top point of the digastric groove to establish a coordinate system. And the drilling point was 14.0 mm above and 6.5 mm behind the top point of the digastric groove in the coordinate system.


Asunto(s)
Cadáver , Senos Craneales , Craneotomía , Humanos , Femenino , Masculino , Adulto , Persona de Mediana Edad , Senos Craneales/anatomía & histología , Senos Craneales/cirugía , Craneotomía/métodos , Procedimientos Neuroquirúrgicos/métodos , Anciano , Adulto Joven , Senos Transversos/anatomía & histología , Senos Transversos/cirugía , Cráneo/anatomía & histología , Cráneo/cirugía
18.
Acta Cir Bras ; 39: e392824, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39046039

RESUMEN

PURPOSE: to evaluate biocompatibility and osteogenic potential of hydroxyapatite/alginate composite after its implantation on rat calvarian critical bone defect. METHODS: thirty adults male Wistar rats were randomly distributed into two groups: GHA - critical bone defect filled with hydroxyapatite/alginate composite granules (HA/Alg) and CG - critical bone defect without biomaterial; evaluated at biological points of 15, 45 and 120 days. RESULTS: the histomorphometrically analyses for GHA showed osteoid matrix deposition (OM) among the granules and towards the center of the defect in centripetal direction throughout the study, with evident new bone formation at 120 days, resulting in filling 4/5 of the initial bone defect. For CG, this finding was restricted to the edges of the bone margins and formation of connective tissue on the residual area was found in all biological points. Inflammatory response on GHA was chronic granulomatous type, discrete and regressive for all biological points. Throughout the study, the CG presented mononuclear inflammatory infiltrate diffuse and regressive. Histomorphometry analyses showed that OM percentage was evident for GHA group when compared to CG group in all analyzed periods (p > 0.05). CONCLUSIONS: the biomaterial evaluated at this study showed to be biocompatible, bioactive, osteoconductive and biodegradable synchronously with bone formation.


Asunto(s)
Alginatos , Materiales Biocompatibles , Regeneración Ósea , Sustitutos de Huesos , Durapatita , Ensayo de Materiales , Ratas Wistar , Animales , Masculino , Regeneración Ósea/efectos de los fármacos , Regeneración Ósea/fisiología , Alginatos/farmacología , Durapatita/farmacología , Durapatita/uso terapéutico , Materiales Biocompatibles/uso terapéutico , Sustitutos de Huesos/uso terapéutico , Distribución Aleatoria , Osteogénesis/efectos de los fármacos , Osteogénesis/fisiología , Ácidos Hexurónicos/farmacología , Ácido Glucurónico/farmacología , Cráneo/cirugía , Cráneo/efectos de los fármacos , Factores de Tiempo , Ratas , Reproducibilidad de los Resultados
19.
Eur Spine J ; 33(8): 3027-3033, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38967802

RESUMEN

PURPOSE: To evaluate the efficacy of calvarial graft (CG) in craniovertebral fusion procedures in children at a single single center. METHODS: Paediatric patients in whom CG had been used as the sole construct, or to augment a semi-rigid construct were identified from a prospective operative database. Age, underlying diagnosis and clinical presentation were obtained from review of the electronic patient record. The primary outcome was bony fusion confirmed on CT. Additional outcome measures were donor site morbidity and need for further surgery. RESULTS: From 82 paediatric CVJ procedures, CG was used in 15 patients with a mean age of 4.1 (± 3.52) years. Aetiology comprised skeletal dysplasia (n = 12), congenital anomaly of segmentation (n = 1) and cervical trauma (n = 2). Myelopathy was the most common clinical finding (9/15), followed by cervical pain (3/15). The indications for surgery comprised atlanto-axial subluxation (8/15), basilar invagination with compression (2/15), and cervicomedullary compression without instability but deemed at risk of instability following decompression (4/15). CG was used in three scenarios: (i) CG + wire only (n = 10); (ii) CG + semirigid instrumentation (n = 3); (iii) CG to augment rigid instrumented fixation (n = 2). In 13 patients a Halo-body Jacket was used peri-operatively. At a mean time of 4.4 months following surgery, 80% of cases had radiological evidence of fusion. CONCLUSION: Full thickness calvarial bone graft is readily available, has good structural integrity and is associated with minimal donor site morbidity. CG should be considered for use as a sole construct, or to augment semi-rigid constructs when instrumented fixation is precluded.


Asunto(s)
Trasplante Óseo , Fusión Vertebral , Humanos , Fusión Vertebral/métodos , Preescolar , Masculino , Femenino , Trasplante Óseo/métodos , Niño , Articulación Atlantoaxoidea/cirugía , Articulación Atlantoaxoidea/diagnóstico por imagen , Resultado del Tratamiento , Cráneo/cirugía , Lactante , Vértebras Cervicales/cirugía , Vértebras Cervicales/diagnóstico por imagen , Adolescente
20.
Ann Afr Med ; 23(2): 176-181, 2024 Apr 01.
Artículo en Francés, Inglés | MEDLINE | ID: mdl-39028166

RESUMEN

BACKGROUND: Decompressive craniectomy (DC) is a surgical procedure to treat refractory increase in intracranial pressure. DC is frequently succeeded by cranioplasty (CP), a reconstructive procedure to protect the underlying brain and maintain cerebrospinal fluid flow dynamics. However, complications such as seizures, fluid collections, infections, and hydrocephalus can arise from CP. Our aim is to investigate these complications and their possible risk factors and to discuss whether early or late CP has any effect on the outcome. MATERIALS AND METHODS: A single-center retrospective cohort study was performed, including patients who underwent CP after DC between January 2014 and January 2022. Relevant information was collected such as demographics, type of brain injury, materials used in CP, timing between DC and CP, and postoperative complications. Ultimately, 63 patients were included in our study. We also compared the complication rate between patients who underwent late CP after DC (>90 days) against patients who underwent early CP (<90 days). RESULTS: Most patients were male (78%). The sample median age was 29 years, with pediatric patients, accounting for 36% of the samples. Overall complication rate was 57% and they were seizure/epilepsy in 50% of the patients, fluid collection (28%), infections (25%), posttraumatic hydrocephalus (17%), and bone defect/resorption (3%). Twenty-two percent of patients with complications required reoperation and underwent a second CP. The median (interquartile range) duration between the craniotomy and the CP was 56 (27-102) days, with an early (≤3 months) percentage of 68%. We found no significant difference between early (≤3 months) and late (>3 months) CP regarding complication rates. CONCLUSION: Despite CP being a simple procedure, it has a considerable rate of complications. Therefore, it is important that surgeons possess adequate knowledge about such complications to navigate these challenges more effectively.


Résumé Contexte:La craniectomie décompressive (DC) est une intervention chirurgicale destinée à traiter l'augmentation réfractaire de la pression intracrânienne. La DC est fréquemment remplacée par une cranioplastie (CP), une procédure reconstructive visant à protéger le cerveau sous-jacent et à maintenir la dynamique du flux du liquide céphalo-rachidien. Cependant, des complications telles que des convulsions, des collections de liquides, des infections et une hydrocéphalie peuvent survenir en raison de la CP. Notre objectif est d'étudier ces complications et leurs facteurs de risque possibles et de discuter si une CP précoce ou tardive a un effet sur le résultat.Matériels et méthodes:Une étude de cohorte rétrospective monocentrique a été réalisée, incluant des patients ayant subi une PC après une DC entre janvier 2014 et janvier 2022. Des informations pertinentes ont été collectées telles que les données démographiques, le type de lésion cérébrale, les matériaux utilisés dans la PC, le timing entre la DC et CP et complications postopératoires. Au final, 63 patients ont été inclus dans notre étude. Nous avons également comparé le taux de complications entre les patients ayant subi une CP tardive après une DC (> 90 jours) et ceux ayant subi une CP précoce (<90 jours).Résultats:La plupart des patients étaient des hommes (78 %). L'âge médian de l'échantillon était de 29 ans, les patients pédiatriques représentant 36 % des échantillons. Le taux global de complications était de 57 % et il s'agissait de convulsions/épilepsie chez 50 % des patients, d'accumulation de liquide (28 %), d'infections (25 %), d'hydrocéphalie post-traumatique (17 %) et de défauts/résorptions osseuses (3 %). Vingt­deux pour cent des patients présentant des complications ont dû être réopérés et ont subi une deuxième CP. La durée médiane (intervalle interquartile) entre la craniotomie et la CP était de 56 (27 à 102) jours, avec un pourcentage précoce (≤ 3 mois) de 68 %. Nous n'avons trouvé aucune différence significative entre la PC précoce (≤ 3 mois) et tardive (> 3 mois) en ce qui concerne les taux de complications.Conclusion:Bien que la CP soit une procédure simple, elle entraîne un taux de complications considérable. Il est donc important que les chirurgiens possèdent des connaissances adéquates sur ces complications pour relever ces défis plus efficacement.


Asunto(s)
Craniectomía Descompresiva , Hidrocefalia , Procedimientos de Cirugía Plástica , Complicaciones Posoperatorias , Centros de Atención Terciaria , Humanos , Masculino , Femenino , Estudios Retrospectivos , Craniectomía Descompresiva/métodos , Craniectomía Descompresiva/efectos adversos , Adulto , Complicaciones Posoperatorias/epidemiología , Procedimientos de Cirugía Plástica/métodos , Resultado del Tratamiento , Hidrocefalia/cirugía , Persona de Mediana Edad , Convulsiones/cirugía , Adolescente , Niño , Países en Desarrollo , Factores de Riesgo , Cráneo/cirugía , Adulto Joven , Lesiones Encefálicas/cirugía , Craneotomía/métodos , Craneotomía/efectos adversos , Hipertensión Intracraneal/cirugía
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