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1.
World Neurosurg ; 127: e1172-e1175, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31003027

RESUMO

OBJECTIVE: This video article describes and illustrates the function and application of the intracerebral microinjection instrument (IMI). This newly developed technology allows delivery of therapeutic agents within the human brain in complex 3-dimensional arrays using a single pass or minimal overlying penetrations through brain tissue. METHODS: The IMI uses a delivery microcannula with a reduced diameter that minimizes local trauma and is capable of delivering precise volumes of therapeutic agents to discrete brain substructures. The IMI also permits simultaneous recording of neural activity during the delivery procedure, enabling extreme precision using electrophysiologic mapping. Surgical planning software designed specifically for the IMI enables strategic placement of multiple injections. RESULTS: This technology platform is presently being used successfully to deliver therapeutic stem cells to restore function in stroke patients. CONCLUSIONS: Additional applications of the IMI include delivery of viral vectors for gene therapy, infusion of neurotrophic factors, targeted delivery of chemotherapeutic agents, and delivery of antiretroviral medications.


Assuntos
Encéfalo/diagnóstico por imagem , Sistemas de Liberação de Medicamentos/instrumentação , Sistemas de Liberação de Medicamentos/métodos , Imagem Tridimensional/métodos , Microinjeções , Humanos , Injeções Intraventriculares , Técnicas Estereotáxicas/instrumentação
2.
Clinics (Sao Paulo) ; 74: e573, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30994703

RESUMO

OBJECTIVES: The pedunculopontine nucleus (PPN) is considered a promising new target for neurostimulation in Parkinson's disease (PD) patients with postural instability and gait disturbance that is refractory to other treatment modalities. However, the PPN is typically difficult to visualize with magnetic resonance imaging (MRI) at clinical field strengths, which greatly limits the PPN as a viable surgical target for deep brain stimulation (DBS). Thus, the aim of this study is to directly visualize the PPN based on 7.0T ultrahigh-field MRI. METHODS: Five PD patients were enrolled and scanned using the MP2RAGE sequence on a 7.0T ultrahigh-field MRI scanner. Then, the MP2RAGE sequences were imported into a commercially available navigation system. The coordinates of the directly localized PPN poles were recorded in the navigation system relative to the anterior commissure-posterior commissure plane. RESULTS: Our results indicated that the PPN presented intermediate signal intensity in the 7.0T ultrahigh-field MR images in comparison with the surrounding structure, such as the hypo-intensity of the periaqueductal gray and the hyperintensity of the neighboring white matter tracts, in PD patients. The mean coordinates for the rostral and caudal poles of PPN were 6.50 mm and 7.20 mm lateral, 1.58 mm and 2.21 mm posterior, and 8.89 mm and 13.83 mm relative to the posterior commissure. CONCLUSION: Our findings provide, for the first time, direct visualization of the PPN using the MP2RAGE sequence on a 7.0T ultrahigh-field MRI, which may improve the accuracy of stereotactic targeting of the PPN and improve the outcomes in patients undergoing DBS.


Assuntos
Aumento da Imagem/instrumentação , Imagem por Ressonância Magnética/métodos , Doença de Parkinson/diagnóstico por imagem , Núcleo Tegmental Pedunculopontino/diagnóstico por imagem , Adulto , Confiabilidade dos Dados , Feminino , Humanos , Aumento da Imagem/métodos , Processamento de Imagem Assistida por Computador/instrumentação , Processamento de Imagem Assistida por Computador/métodos , Imagem por Ressonância Magnética/instrumentação , Masculino , Pessoa de Meia-Idade , Técnicas Estereotáxicas/instrumentação
3.
World Neurosurg ; 127: 436-441, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30974271

RESUMO

BACKGROUND: Clearpoint Smartframe is a magnetic resonance imaging-compatible stereotactic system often used to perform magnetic resonance imaging-guided biopsies. The system is typically mounted on the scalp through screws that pierce the skin and penetrate the outer table of the cranium. However, the frame can also be configured to be mounted directly onto the skull. CASE DESCRIPTION: Here, we describe the clinical context well suited for a skull-mount Clearpoint Smartframe surgery. The patient suffered from a subcentimeter right parafourth ventricular contrast-enhancing lesion with hydrocephalus and underwent a right suboccipital needle biopsy followed by an occipital ventriculoperitoneal shunt. Although the hydrocephalus resolved with the ventriculoperitoneal shunt, the biopsy sample proved nondiagnostic. The patient underwent a second procedure during which the Clearpoint Smartframe was mounted onto the skull through space dissected free during the previous surgery. Diagnostic biopsy (H3K27 glioma) was performed followed by stereotactic laser ablation of the lesion. CONCLUSIONS: We describe a case in which the skull mount Clearpoint Smartframe was used to biopsy and ablate a midline H3K27 glioma.


Assuntos
Neoplasias Encefálicas/cirurgia , Glioma/cirurgia , Terapia a Laser/instrumentação , Procedimentos Neurocirúrgicos/instrumentação , Crânio/cirurgia , Técnicas Estereotáxicas/instrumentação , Adulto , Neoplasias Encefálicas/patologia , Desenho de Equipamento , Glioma/patologia , Humanos , Hidrocefalia/patologia , Hidrocefalia/cirurgia , Biópsia Guiada por Imagem/instrumentação , Imagem por Ressonância Magnética Intervencionista/instrumentação , Masculino , Imagem Multimodal , Tomografia Computadorizada por Raios X , Derivação Ventriculoperitoneal/instrumentação , Derivação Ventriculoperitoneal/métodos
4.
J Appl Clin Med Phys ; 20(5): 27-36, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30950167

RESUMO

BACKGROUND: The stereotactic frame represents the mainstay of accuracy for targeting in stereotactic procedures. Any distortion of the frame may induce a significant source of error for the stereotactic coordinates. OBJECTIVE: To analyze the sources of distortion of the Leksell frame G induced by fixation to the patient's head and to evaluate the clinical impact of frame distortion on the accuracy of targeting in stereotactic procedures. METHODS: We analyzed the torques exerted on the fixation screws after frame placement in a series of patients treated stereotactically by an experienced team. We studied the risk for frame bending in an experimental model of stereotactic frame fixation, with increasing torque of fixation screws in a homogeneous and heterogeneous distribution of torques between the four screws. We assessed the impact of expanding dimensions of bending of the Leksell frame both on surgeries utilizing the stereotactic frame, and on radiosurgical procedures with the Gamma Knife. RESULTS: Frames were fixed clinically at a range of torques of 0.147-0.522 Nm (mean = 0.348 Nm). The torques did not vary significantly with time. Heterogeneity between the two opposite pairs of screws is often limited, but can reach 96.3%. Distortion of the frame may occur even at minimal levels of torque. Heterogeneity between the two opposite pairs of screws will significantly raise the amount of frame distortion. We found a direct correlation between measures of the frame distortion and extend of the deviation from the stereotactic target in clinical models of stereotactic procedures. CONCLUSION: Stereotactic frames were subjected to distortion due to the torque used for frame fixation. The risk of distortion increased with the torque used and the heterogeneity between the torques of the fixation screws. Distortion of the frame was a significant source of inaccuracy of targeting for stereotactic procedures in clinical practice.


Assuntos
Calibragem , Neoplasias/cirurgia , Neurocirurgia/instrumentação , Imagens de Fantasmas , Radiocirurgia/instrumentação , Técnicas Estereotáxicas/instrumentação , Desenho de Equipamento , Humanos , Neurocirurgia/normas , Radiocirurgia/normas
5.
Res Vet Sci ; 124: 79-84, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30856434

RESUMO

The treatment of intracranial lesions requires a precise diagnosis with subsequent identification of an adequate therapeutic approach. Stereotactic tumor biopsy may be considered the safest neurosurgical procedure in terms of anticipated results and potential surgical complications. The aim of the present paper was to demonstrate a new method of stereotactic biopsy, based on a patient-specific 3D printed platform in dogs. The system was tested on two canine cadavers, a small (Shih Tzu) and a large (Labrador) breed. Imaginary biopsy targets were defined in a superficial (caudate nucleus) and a deep (piriform lobe) position. Based on 3 Tesla MRI, individualized stereotactic platforms were designed using a semi-automatic approach, and manufactured additively using ABS M30. A pre- and intra-operative CT was performed to compare the planned vs. the realized needle position for precision analyses of the procedure. The target points varied with a precision between 0.09 mm and 0.48 mm. Manufacturing time required 480 to 700 min per platform. The presented patient-specific stereotactic system seems a suitable instrument for application in small animal neurosurgery. In particular, the implementation of relevant stereotactic data may help performing the procedure in rapid sequence and with higher precision than currently-used systems. Required adjustments and adaptions to the respective anatomical conditions are omitted and make the procedure reliable and safe.


Assuntos
Biópsia/veterinária , Encéfalo/patologia , Impressão Tridimensional , Técnicas Estereotáxicas/veterinária , Animais , Biópsia/instrumentação , Biópsia/métodos , Cadáver , Cães , Técnicas Estereotáxicas/instrumentação
7.
J Neuroimmunol ; 330: 44-47, 2019 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-30798192

RESUMO

PURPOSE: Chronic autoimmune epilepsy is an increasingly recognised entity however its clinical and electrographic features remain poorly understood. We present a case undergoing diagnostic Stereo-electroencephalography implantation that was found to have a multifocal perisylvian epilepsy with unique electrographic features and is now seizure free with immunotherapy. METHODS: The patient had antibody negative refractory perisylvian epilepsy and underwent implantation of the perisylvian-temporal networks. Immunomodulatory treatment was administered during SEEG. RESULTS: SEEG demonstrated a multifocal perisylvian epilepsy with strong involvement of the posterior insula. There was almost continuous spiking seen interictally from multiple foci within the right hemisphere and independent seizures were generated from 5 locations. After treatment with intravenous methylprednisone and immunoglobulin during SEEG, spiking and seizures terminated while still off anti-seizure medications. The patient remains seizure free on immunotherapy. CONCLUSION: This case highlights the importance of considering autoimmunity in the differential diagnosis of refractory epilepsy, especially perisylvian epilepsy. It also highlights the need to define a clinical phenotype associated with autoantibodies in epilepsy, as there are likely many cases who are not positive for one of the commercially available tests. This case also provides insights into the possible features of an electroclinical syndrome associated with autoimmunity.


Assuntos
Doenças Autoimunes do Sistema Nervoso/diagnóstico , Eletroencefalografia/instrumentação , Eletroencefalografia/métodos , Epilepsia/diagnóstico , Técnicas Estereotáxicas , Adulto , Doenças Autoimunes do Sistema Nervoso/tratamento farmacológico , Doenças Autoimunes do Sistema Nervoso/fisiopatologia , Eletrodos Implantados , Epilepsia/tratamento farmacológico , Epilepsia/fisiopatologia , Feminino , Glucocorticoides/administração & dosagem , Humanos , Fatores Imunológicos/administração & dosagem , Técnicas Estereotáxicas/instrumentação
8.
Methods Mol Biol ; 1880: 529-534, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30610719

RESUMO

Macroautophagy is the process to remove intracellular organelles or proteins by using autophagosome that is composed of autophagy proteins such as atg3, atg7, and atg8/LC3 (Mizushima, et al. Annu Rev Cell Dev Biol. 27:107-132, 2011). Here, we develop a useful method for in vivo imaging of autophagosome under the two-photon microscopy. Time-lapse imaging of LC3-ECFP enables us to quantify the dynamics of number, size, and signal intensity of autophagosomes in neurons or in other types of cells in the brain.


Assuntos
Autofagossomos/metabolismo , Autofagia/fisiologia , Encéfalo/diagnóstico por imagem , Microscopia Intravital/métodos , Microscopia de Fluorescência por Excitação Multifotônica/métodos , Animais , Proteínas Relacionadas à Autofagia/metabolismo , Encéfalo/citologia , Encéfalo/metabolismo , Células HEK293 , Humanos , Processamento de Imagem Assistida por Computador/instrumentação , Processamento de Imagem Assistida por Computador/métodos , Microscopia Intravital/instrumentação , Proteínas Luminescentes/química , Proteínas Luminescentes/genética , Camundongos , Camundongos Transgênicos , Microscopia de Fluorescência por Excitação Multifotônica/instrumentação , Proteínas Associadas aos Microtúbulos/análise , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Neurônios/metabolismo , Técnicas Estereotáxicas/instrumentação , Imagem com Lapso de Tempo/instrumentação , Imagem com Lapso de Tempo/métodos
9.
J Neurosurg Sci ; 63(2): 194-199, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26977636

RESUMO

BACKGROUND: The specificity of imaging alone in diagnosing posterior fossa lesions is insufficient, hence the importance of biopsy for diagnostic, therapeutic and prognostic purposes. Concerning the operative technique, many studies have demonstrated the superior safety of stereotactic biopsy over craniotomy and superior accuracy of frame-based systems over frameless ones as far as the posterior fossa is concerned; however versatile, frame-based instruments bear some intrinsic limitations in the positioning of frame in lower lesions mainly in short neck and kyphotic patients. For all these reasons, a more proficient technical bioptic approach to the posterior fossa and lower brainstem is sometimes required. METHODS: In order to obtain a specimen a Leksell System (Elekta®) constituted by the Leksell Coordinate G Frame (Article No: 014611), 4 adjustable posts (Article No: 1006476), 4 reusable screws (Article No: 1006581), an open indicator box (Article No: 1006559), a Leksell Multi-purpose Stereotactic Arc (Article No: 1008174) and a Sedan Needle (Article No: A2430-01) are required. RESULTS: This is a simple and reliable technique to obtain a brainstem/cerebellar specimen maintaining unchanged the know risks of the procedure, as well the morbidity and mortality. We otherwise recommend this procedure to be performed by a team of neurosurgeons trained in stereotaxy. CONCLUSIONS: If meticulously planned, our modified procedure provide a direct and precise access to deep seated areas of the posterior fossa and brainstem and is particularly helpful in those patients with short neck and kyphosis in which is crucial obtain an istopathologic diagnosis in lower posterior fossa.


Assuntos
Neoplasias do Tronco Encefálico/cirurgia , Neoplasias Infratentoriais/cirurgia , Neuronavegação/instrumentação , Neuronavegação/métodos , Técnicas Estereotáxicas/instrumentação , Biópsia/métodos , Humanos , Cirurgia Assistida por Computador/métodos
10.
World Neurosurg ; 123: e450-e456, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30500594

RESUMO

OBJECTIVE: Stereotactic biopsy is a standard procedure in neurosurgery. In addition to or even replacing frame-based stereotaxy, some centers also use frameless imaging-based techniques and more recently robotic systems. Here we report a retrospective analysis of our experience with 102 consecutive biopsies performed in our institution using the neuromate robotic device. METHODS: Between March 2013 and April 2018, 102 robot-assisted frameless biopsies were performed in 100 consecutive patients (median age/range: 66/7-86 years, male: 64). Target lesions were deep-seated (insula, basal ganglia, thalamus, midbrain, cerebellar peduncle) in 29 (28.4%) and/or small (<15 mm) in 24 (23.5%) cases. We retrospectively analyzed the histopathologic results as well as complications and the duration of the procedures. RESULTS: A definite histologic diagnosis could be established in 94 of 102 procedures (92.2%; 94/100 patients = 94.0%), including 67 glial and glioneuronal tumors, 16 central nervous system lymphomas, 7 metastases, 1 primitive neuroectodermal tumor, and 5 cases with inflammatory or infectious disorders. There were no infectious complications. A total of 13 cases (12.7%) suffered from biopsy-related hemorrhages >10 mm; however, persistent surgery-related neurologic worsening was seen in only 3 (2.9%). The average operating time was 10 minutes for placement of the localizing device under local anesthesia and 30 minutes for the actual biopsy procedure. CONCLUSIONS: Robot-assisted fameless stereotactic biopsies using the neuromate robot are an alternative to frame-based stereotaxy with a similar diagnostic yield and comparable complication rates.


Assuntos
Neoplasias Encefálicas/patologia , Encéfalo/patologia , Linfoma/patologia , Procedimentos Cirúrgicos Robóticos/instrumentação , Técnicas Estereotáxicas/instrumentação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia/instrumentação , Perda Sanguínea Cirúrgica/estatística & dados numéricos , Neoplasias do Sistema Nervoso Central/patologia , Criança , Desenho de Equipamento , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
11.
Ann Biomed Eng ; 47(2): 335-353, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30377898

RESUMO

Recent technological developments in magnetic resonance imaging (MRI) and stereotactic techniques have significantly improved surgical outcomes. Despite the advantages offered by the conventional MRI-guided stereotactic neurosurgery, the robotic-assisted stereotactic approach has potential to further improve the safety and accuracy of neurosurgeries. This review aims to provide an update on the potential and continued growth of the MRI-guided stereotactic neurosurgical techniques by describing the state of the art in MR conditional stereotactic devices including manual and robotic-assisted. The paper also presents a detailed overview of MRI-guided stereotactic devices, MR conditional actuators and encoders used in MR conditional robotic-assisted stereotactic devices. The review concludes with several research challenges and future perspectives, including actuator and sensor technique, MR image guidance, and robot design issues.


Assuntos
Imagem por Ressonância Magnética/instrumentação , Imagem por Ressonância Magnética/mortalidade , Procedimentos Cirúrgicos Robóticos/instrumentação , Procedimentos Cirúrgicos Robóticos/métodos , Técnicas Estereotáxicas/instrumentação , Humanos
12.
J Neurosurg ; 129(Suppl1): 125-132, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30544292

RESUMO

OBJECTIVEThe aim of this study was to compare 3 different methods to assess the geometrical distortion of two 1.5-T and one 3-T magnetic resonance (MR) scanners and to evaluate co-registration accuracy. The overall uncertainty of each particular method was also evaluated.METHODSThree different MR phantoms were used: 2 commercial CIRS skull phantoms and PTGR known target phantom and 1 custom cylindrical Perspex phantom made in-house. All phantoms were fixed in the Leksell stereotactic frame and examined by a Siemens Somatom CT unit, two 1.5-T Siemens (Avanto and Symphony) MRI systems, and one 3-T Siemens (Skyra) MRI system. The images were evaluated using Leksell GammaPlan software, and geometrical deviation of the selected points from the reference values were determined. The deviations were further investigated for both definitions including fiducial-based and co-registration-based in the case of the CIRS phantom images. The same co-registration accuracy assessment was also performed for a clinical case. Patient stereotactic imaging was done on 3-T Skyra, 1.5-T Avanto, and CT scanners.RESULTSThe accuracy of the CT scanner was determined as 0.10, 0.30, and 0.30 mm for X, Y, and Z coordinates, respectively. The total estimated uncertainty in distortion measurement in one coordinate was determined to be 0.32 mm and 0.14 mm, respectively, for methods using and not using CT as reference imaging. Slightly more significant distortions were observed when using the 3-T than either 1.5-T MR units. However, all scanners were comparable within the estimated measurement error. Observed deviation/distortion for individual X, Y, and Z stereotactic coordinates was typically within 0.50 mm for all 3 scanners and all 3 measurement methods employed. The total radial deviation/distortion was typically within 1.00 mm. Maximum total radial distortion was observed when the CIRS phantom was used; 1.08 ± 0.49 mm, 1.15 ± 0.48 mm, and 1.35 ± 0.49 mm for Symphony, Avanto, and Skyra, respectively. The co-registration process improved image stereotactic definition in a clinical case in which fiducial-based stereotactic definition was not accurate; this was demonstrated for 3-T stereotactic imaging in this study. The best results were shown for 3-T MR image co-registration with CT images improving image stereotactic definition by about 0.50 mm. The results obtained with patient data provided a similar trend of improvement in stereotactic definition by co-registration.CONCLUSIONSAll 3 methods/phantoms used were evaluated as satisfactory for the image distortion measurement. The method using the PTGR phantom had the lowest uncertainty as no reference CT imaging was needed. Image co-registration can improve stereotactic image definition when fiducial-based definition is not accurate.


Assuntos
Imagem por Ressonância Magnética/instrumentação , Imagem por Ressonância Magnética/métodos , Imagens de Fantasmas , Técnicas Estereotáxicas , Artefatos , Humanos , Processamento de Imagem Assistida por Computador , Modelos Anatômicos , Reprodutibilidade dos Testes , Crânio , Software , Técnicas Estereotáxicas/instrumentação , Tomografia Computadorizada por Raios X
13.
Stereotact Funct Neurosurg ; 96(6): 364-369, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30566953

RESUMO

BACKGROUND: The control of the anatomic position of the active contacts is essential to understand the effects and adapt the settings of the neurostimulation. The localization is commonly assessed by a registration between the preoperative MRI and the postoperative CT scan. However, its accuracy depends on the quality of the registration algorithm and many software programs are available. OBJECTIVE: To compare the localization of implanted deep brain stimulation (DBS) leads in the subthalamic nucleus (STN) between four registration devices. METHODS: The preoperative stereotactic MRI was co-registered and fused with the 3-month postoperative CT scan in 27 patients implanted in the STN for Parkinson's disease (53 leads). Localizations of the active contacts were calculated in the stereotactic frame space and compared between software programs. RESULTS: The coordinates of the active contacts were different between software programs in the 3 axes (p < 0.001) with a mean vectorial error between the deepest contact locations of 1.17 mm (95% CI 1.09-1.25). CONCLUSION: We found a small but significant difference in the coordinates calculated on four different devices. These results have to be considered when performing studies comparing active contact locations or when following patients with an implanted DBS lead.


Assuntos
Estimulação Encefálica Profunda/métodos , Eletrodos Implantados , Imagem por Ressonância Magnética/métodos , Software , Núcleo Subtalâmico/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Estimulação Encefálica Profunda/instrumentação , Feminino , Humanos , Imagem Tridimensional/métodos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/cirurgia , Técnicas Estereotáxicas/instrumentação , Núcleo Subtalâmico/fisiologia , Núcleo Subtalâmico/cirurgia
14.
Comput Assist Surg (Abingdon) ; 23(1): 42-52, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30497291

RESUMO

OBJECTIVE: This paper proposes the development of a novel electromagnetic tracking system for navigation surgery. Main objective is to provide a system able to operate in a wide tracking volume to make easier and efficient the surgical procedures by assuring high measurement accuracy. METHODS: A new field generator consisting in five transmitting coils excited with Frequency Division Multiplexing technique has been developed. Attention is devoted to designing and arrangement of the coils to assure high sensitivity, system scalability and a homogeneous magnetic field inside working volume. A suitable technique based on Look-Up-Table is applied for sensor position calculation and an anthropomorphic robot is used for table calibration. RESULTS: Experimental tests highlight a good repeatability of the measurement data and a negligible noise influence for the proposed system. The obtained tracking volume is wider with respect to the commercial tracking device used in surgical applications and seem promising. CONCLUSION: The main characteristic of the developed system consists of: scalable and modular configuration of Field Generator, high measured sensitivity due to the increased number of transmitting coils with respect to the classical configuration and large tracking volume. The development of the proposed magnetic tracking systems with high accuracy and wide working volume allows to promote broader utilization of advantaged techniques in surgery procedures for both improving the effectiveness and decreasing the invasiveness of medical interventions.


Assuntos
Técnicas Estereotáxicas/instrumentação , Cirurgia Assistida por Computador/instrumentação , Campos Eletromagnéticos , Desenho de Equipamento , Humanos , Modelos Teóricos , Dispositivos Ópticos , Imagens de Fantasmas , Cirurgia Assistida por Computador/métodos
15.
Int J Oral Maxillofac Implants ; 33(6): 1219-1228, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30427952

RESUMO

PURPOSE: This research aimed to propose a three-dimensional (3D) augmented reality navigation method with point cloud-based image-patient registration that could merge virtual images in the real environment for dental implants using a 3D image overlay and to evaluate its feasibility. MATERIALS AND METHODS: A total of 12 rapid prototyping mandibular models were fabricated using a 3D printing method and were divided into two groups: 3D augmented reality-guided group and traditional two-dimensional (2D) image-guided group. A point cloud-based preoperative image-to-patient registration method was introduced to replace the traditional point-to-point registration. After the registration, dental implant surgery was performed in the two model groups using an augmented reality-guided navigation method and a traditional two-dimensional image-guided navigation method. The planned and actual postoperative implant positions were compared for measuring positional implantation errors. The surgery time was also recorded and compared between the two groups. RESULTS: In the model experiment, the root-mean-square deviation of registration was 0.54 mm, and the implant surgery results showed < 1.5-mm mean linear deviation and < 5.5-degree angular deviation. The augmented reality-guided implantation showed smaller horizontal, vertical, and angular errors in the apical areas of the central incisor and the canine region. The surgery time using the augmented reality-guided navigation method was significantly shorter than that using the two-dimensional (2D) image-guided navigation method (P < .05). Moreover, the volunteer experiment demonstrated that the preoperative 3D models in situ accurately overlaid onto the surgical site. CONCLUSION: The proposed point cloud-based registration method can achieve excellent registration accuracy. Dental implant placement guided by the proposed 3D augmented reality navigation method showed better accuracy and applicability, as well as higher efficiency, than the traditional 2D image navigation method.


Assuntos
Implantes Dentários , Imagem Tridimensional/métodos , Cirurgia Assistida por Computador/métodos , Humanos , Mandíbula/cirurgia , Boca Edêntula/cirurgia , Imagens de Fantasmas , Impressão Tridimensional , Técnicas Estereotáxicas/instrumentação , Tomografia Computadorizada por Raios X/métodos , Interface Usuário-Computador
16.
Acta Neurochir (Wien) ; 160(12): 2489-2500, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30413938

RESUMO

BACKGROUND: Stereoelectroencephalography (SEEG) is an effective technique to help to locate and to delimit the epileptogenic area and/or to define relationships with functional cortical areas. We intend to describe the surgical technique and verify the accuracy, safety, and effectiveness of robot-assisted SEEG in a newly created SEEG program in a pediatric center. We focus on the technical difficulties encountered at the early stages of this program. METHODS: We prospectively collected SEEG indication, intraoperative events, accuracy calculated by fusion of postoperative CT with preoperative planning, complications, and usefulness of SEEG in terms of answering preimplantation hypothesis. RESULTS: Fourteen patients between the ages of 5 and 18 years old (mean 10 years) with drug-resistant epilepsy were operated on between April 2016 and April 2018. One hundred sixty-four electrodes were implanted in total. The median entry point localization error (EPLE) was 1.57 mm (1-2.25 mm) and the median target point localization error (TPLE) was 1.77 mm (1.2-2.6 mm). We recorded seven intraoperative technical issues. Two patients suffered complications: meningitis without demonstrated germ in one patient and a right frontal hematoma in the other. In all cases, the SEEG was useful for the therapeutic decision-making. CONCLUSION: SEEG has been useful for decision-making in all our pediatric patients. The robotic arm is an accurate tool for the insertion of the deep electrodes. Nevertheless, it is an invasive technique not risk-free and many problems can appear at the beginning of a robotic arm-assisted SEEG program that must be taken into account beforehand.


Assuntos
Epilepsia Resistente a Medicamentos/cirurgia , Eletroencefalografia/métodos , Complicações Pós-Operatórias/epidemiologia , Robótica/métodos , Técnicas Estereotáxicas/efeitos adversos , Adolescente , Criança , Pré-Escolar , Tomada de Decisão Clínica , Epilepsia Resistente a Medicamentos/diagnóstico , Eletrodos Implantados/efeitos adversos , Eletrodos Implantados/normas , Eletroencefalografia/efeitos adversos , Eletroencefalografia/instrumentação , Eletroencefalografia/normas , Feminino , Humanos , Masculino , Robótica/instrumentação , Robótica/normas , Técnicas Estereotáxicas/instrumentação , Técnicas Estereotáxicas/normas
17.
Stereotact Funct Neurosurg ; 96(5): 327-334, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30481770

RESUMO

BACKGROUND/AIMS: Technological advancements had a serious impact on the evolution of robotic systems in stereotactic neurosurgery over the last three decades and may turn robot-assisted stereotactic neurosurgery into a sophisticated alternative to purely mechanical guiding devices. OBJECTIVES: To compare robot-assisted and conventional frame-based deep brain stimulation (DBS) surgery with regard to accuracy, precision, reliability, duration of surgery, intraoperative imaging quality, safety and maintenance using a standardized setup. METHODS: Retrospective evaluation of 80 consecutive patients was performed who underwent DBS surgery using either a frame-based mechanical stereotactic guiding device (n = 40) or a stereotactic robot (ROSA Brain, MedTech, Montpellier, France) (n = 40). RESULTS: The mean accuracy of robot-assisted and conventional lead implantation was 0.76 mm (SD: 0.37 mm, range: 0.17-1.52 mm) and 1.11 mm (SD: 0.59 mm, range: 0.10-2.90 mm), respectively. We observed a statistically significant difference in accuracy (p < 0.001) when comparing lateral deviations between both modalities. Furthermore, a statistical significance was observed when investigating the proportion of values exceeding 2.00 mm between both groups (p = 0.013). In 8.75% (n = 7) of conventionally implanted leads, lateral deviations were greater than 2.0 mm. With a maximum value of 1.52 mm, this threshold was never reached during robot-guided DBS. The mean duration of DBS surgery could be reduced significantly (p < 0.001) when comparing robot-guided DBS (mean: 325.1 ± 81.6 min) to conventional lead implantation (mean: 394.8 ± 66.6 min). CONCLUSIONS: Robot-assisted DBS was shown to be superior to conventional lead implantation with respect to accuracy, precision and operation time. Improved quality control, continuous intraoperative monitoring and less manual adjustment likely contribute to the robotic system's reliability allowing high accuracy during lead implantation despite limited experience. Hence, robot-assisted lead implantation can be considered an appropriate and reliable alternative to purely mechanical devices.


Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/cirurgia , Estimulação Encefálica Profunda/métodos , Procedimentos Neurocirúrgicos/métodos , Procedimentos Cirúrgicos Robóticos/métodos , Técnicas Estereotáxicas , Adulto , Idoso , Feminino , Humanos , Imagem Tridimensional/métodos , Masculino , Pessoa de Meia-Idade , Doenças do Sistema Nervoso/diagnóstico por imagem , Doenças do Sistema Nervoso/cirurgia , Reprodutibilidade dos Testes , Estudos Retrospectivos , Técnicas Estereotáxicas/instrumentação
18.
J Clin Neurosci ; 58: 229-233, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30454691

RESUMO

BACKGROUND: As the bearing structure of fixation device in deep brain stimulation (DBS), burr hole ring is fixed on the skull and used in conjunction with Stimloc and plastic cap. But in patients with traumatic event, excessive movements are likely to bring strain on the anchoring system, which will finally cause the fixation device to fall off from the skull. METHOD: AutoCAD was used to construct two-dimension (2-D) images for traditional burr hole ring and innovative burr hole ring, respectively. According to the 2-D image, pro/Engineer (Pro/E) will be applied to construct the three-dimension (3-D) geometries. And then, 3-D printing technology was used to build the solid model. These two kinds of burr hole rings were divided into two groups: Innovative group (N = 21) and Traditional group (N = 21). Pull-out strength of these two groups of burr hole rings will be measured by manual tensile force testing machine on the full-size skull model, and the data were transmitted to the notebook in real time for recording and further analyzing. RESULT: The fixation strength of the innovative group is stronger than traditional group, pull-out strength value of traditional group and innovative group were 34.08 ±â€¯1.31 N and 99.73 ±â€¯2.14 N, respectively. (P < 0.001). CONCLUSION: We provide an innovative burr hole ring, which can fix on the burr hole steadily. Moreover, 3-D printing technology may be suitable for personalized and customized medical treatment in the future.


Assuntos
Estimulação Encefálica Profunda/métodos , Eletrodos Implantados , Modelos Anatômicos , Impressão Tridimensional , Crânio/diagnóstico por imagem , Trepanação/métodos , Adulto , Estimulação Encefálica Profunda/instrumentação , Humanos , Imagem Tridimensional/instrumentação , Imagem Tridimensional/métodos , Impressão Tridimensional/instrumentação , Crânio/anatomia & histologia , Crânio/cirurgia , Técnicas Estereotáxicas/instrumentação , Trepanação/instrumentação
19.
J Neurosurg Pediatr ; 23(1): 92-97, 2018 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-30265228

RESUMO

Cortical tubers associated with tuberous sclerosis complex (TSC) are potential epileptic foci that are often amenable to resective or ablative surgeries, and controlling seizures at a younger age may lead to improved functional outcomes. MRI-guided laser interstitial thermal therapy (MRgLITT) has become a popular minimally invasive alternative to traditional craniotomy. Benefits of MRgLITT include the ability to monitor the ablation in real time, a smaller incision, shorter hospital stay, reduced blood loss, and reduced postoperative pain. To place the laser probe for LITT, however, stereotaxy is required-which classically involves head fixation with cranial pins. This creates a relative minimum age limit of 2 years old because it demands a mature skull and fused cranial sutures. A novel technique is presented for the application of MRgLITT in a 6-month-old infant for the treatment of epilepsy associated with TSC. To the authors' knowledge this is the youngest patient treated with laser ablation. The authors used a frameless navigation technique with a miniframe tripod system and intraoperative reference points. This technique expands the application of MRgLITT to younger patients, which may lead to safer surgical interventions and improved outcomes for these children.


Assuntos
Epilepsia/terapia , Terapia a Laser/métodos , Imagem por Ressonância Magnética Intervencionista , Esclerose Tuberosa/terapia , Fatores Etários , Edema Encefálico/tratamento farmacológico , Craniotomia/métodos , Epilepsia/etiologia , Feminino , Humanos , Lactente , Complicações Pós-Operatórias/tratamento farmacológico , Técnicas Estereotáxicas/instrumentação , Esclerose Tuberosa/complicações , Esclerose Tuberosa/diagnóstico por imagem
20.
Neural Netw ; 107: 34-47, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30241968

RESUMO

Recently, snake-like robots are proposed to assist experts during medical procedures on internal organs via natural orifices. Despite their well-spelt advantages, applications in radiosurgery is still hindered by absence of suitable designs required for spatial navigations within clustered and confined parts of human body, and inexistence of precise and fast inverse kinematics (IK) models. In this study, a deeply-learnt damped least squares method is proposed for solving IK of spatial snake-like robot. The robot's model consists of several modules, and each module has a pair of serial-links connected with orthogonal twists. For precise control of the robot's end-effector, damped least-squares approach is used to minimize error magnitude in a function modeled over analytical Jacobian of the robot. This is iteratively done until an apt joint vector needed to converge the robot to desired positions is obtained. For fast control and singularity avoidance, a deep network is built for prediction of unique damping factor required for each target point in the robot's workspace. The deep network consists of 11 x 15 array of neurons at the hidden layer, and deeply-learnt with a huge dataset of 877,500 data points generated from workspace of the snake robot. Implementation results for both simulated and actual prototype of an eight-link model of the robot show the effectiveness of the proposed IK method. With error tolerance of 0.01 mm, the proposed method has a very high reachability measure of 91.59% and faster mean execution time of 9.20 (±16.92) ms for convergence. In addition, the method requires an average of 33.02 (±39.60) iterations to solve the IK problem. Hence, approximately 3.6 iterations can be executed in 1 ms. Evaluation against popularly used IK methods shows that the proposed method has very good performance in terms of accuracy and speed, simultaneously.


Assuntos
Aprendizado Profundo , Robótica/métodos , Técnicas Estereotáxicas/instrumentação , Fenômenos Biomecânicos
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