bluuebunny/crossref_metadata_2025 huggingface dataset:
Síndrome metabólico en la edad pediátrica: ¿qué sabemos hasta el momento?
Authors: León Quirós Stephanie , Vargas Guzmán Amanda , Fung Fallas Michelle
Published: August 2021

El síndrome metabólico representa un reto para la salud pública, pues genera un aumento de morbilidad y mortalidad en la población y su prevalencia se encuentra en aumento, en todas las edades. Se debe a una compleja interacción entre factores genéticos, conductuales y ambientales, cuyos efectos nocivos para la salud física del individuo se ha demostrado que inician su afectación desde la vida intrauterina, y se mantienen hasta la edad adulta. Supone un reto diagnóstico en la edad pediátrica, por falta de consenso en su definición y criterios diagnósticos. En cuanto al abordaje también supone un desafío por los múltiples factores a tratar, sin embargo, sí se ha demostrado la importancia de promover en primer lugar la prevención, pues a menor edad y avance de los efectos perjudiciales, mayor es el beneficio que se obtiene, para esto, se entrena a los padres y niños a seguir hábitos saludables de actividad física, patrones de sueño, lactancia materna y posteriormente una dieta saludable. Existen opciones también dirigidas al tratamiento de quien ya lo padece, y una de las estrategias con mejores resultados es el uso de terapia cognitivo-conductual, pero a su vez quedan más objetos de estudio para el futuro.
Parálisis periódica hipopotasemia
Authors: Campos Duarte Katherine , Mesén Román Mónica , Tinoco Chavarría Valeria
Published: August 2021

La parálisis periódica hipocalemia es un trastorno autosómico dominante neuromuscular, que forma parte de un conjunto de enfermedades agrupadas conocidas como canalopatías. Estas diversas patologías se caracterizan por presentar mutaciones en los genes ubicados en los canales iónicos de sodio y calcio dependientes del voltaje, los cuales generan una inexitabilidad de la membrana muscular. Presentan diversas manifestaciones clínicas como episodios de parálisis y debilidad muscular de los cuatro miembros que puede durar horas, no obstante, suelen afectar principalmente a nivel de los miembros inferiores, relacionados con niveles bajos de potasio en sangre. Se describen dos genes causantes de las alteraciones en el voltaje denominados CACNA1S, SCN4A.

El diagnóstico se basa en la historia clínica y sintomatología, así como la confirmación mediante pruebas genéticas, la adecuada educación acerca de la identificación de los factores de riesgo, consejos dietéticos, cambios estilo de vida junto con intervenciones farmacológicas son el tratamiento de elección ideal.
Diarreas congénitas: entidades olvidadas
Authors: Vargas Hernández Mary Paz , Boschini Páez Mariana , Ulloa Velásquez Luis Fernando
Published: August 2021

Las diarreas congénitas son trastornos hereditarios que causan diarrea grave persistente en los lactantes, que a menudo llevan a falla intestinal con desenlace fatal si su diagnóstico no es temprano. Estos trastornos generalmente afectan el epitelio intestinal o sus mecanismos de transporte, ya sea afectando las enzimas digestivas, el sistema inmune o los canales de intercambio de electrolitos. El diagnóstico definitivo de estas enfermedades generalmente incluye estudios genéticos, sin embargo, la biopsia intestinal juega un papel fundamental en la orientación al mismo. Esta revisión presenta un resumen de estas entidades, con énfasis en las más frecuentes a nivel mundial.
El efecto psicológico de la COVID-19 en el personal de salud
Authors: Hidalgo Azofeifa Sybil , Vargas Mena Rodolfo , Carvajal Carpio Leopoldo
Published: August 2021

La pandemia por la COVID-19 ha traído consigo una serie de afectaciones en diferentes sectores sociales, tanto económicos, sociales y evidentemente, de salud. Sin embargo, el personal de salud se ha visto afectado psicológicamente tras la constante exposición a esta enfermedad, prolongadas jornadas laborales y el deterioro tanto físico como mental que la lucha en la primera línea de defensa conlleva. Entre los factores que contribuyen al desarrollo de trastornos de ansiedad, depresión, insomnio entre otros, se encuentran el factor etario, el contexto social y relaciones interpersonales, la falta de capacitación, el nivel de exposición a pacientes contagiados entre otros. Todos estos factores y sus repercusiones en la salud de los trabajadores de la salud son una problemática que no debe pasar desapercibida, esto en virtud de salvaguardar el bienestar de aquellos quienes se encuentran en la primera línea de defensa contra la COVID-19.
Fasciotomía tras emponzoñamiento por Bothrops asper
Authors: Tonos Carlos , Traviezo Valles Luis Eduardo , Pacheco Carlos
Published: August 2021

Bothrops asper es responsable de hasta el 80% del ofidismo del norte de Sudamérica, teniendo su veneno una acción proteolítica y coagulante sobre el miembro afectado. Se realiza un estudio descriptivo, con análisis retrospectivo, con identificación taxonómica y revisión de la literatura. Paciente masculino de doce años, procedente de Sanare, estado Lara, Venezuela, quien es hospitalizado en la Unidad de Cuidados Intensivos por sintomatología grave luego de mordedura por Bothrops en la pierna derecha, recibe quince ampollas de antiveneno, pero la demora del suministro por la grave escases regional del antiveneno y el recibir una dosis alta de la ponzoña, permitieron una intensa acción hemolítica y necrosante sobre los tejidos, presentando síndrome compartimental por lo que ameritó fasciotomía bajo condiciones mínimas aceptables de coagulación. El niño tuvo una buena recuperación salvando el miembro de la amputación. Solo el 20% de los casos de ofidismo llegan a ser graves, produciéndose por inoculaciones superiores a los 300 mg de veneno y a la demora en el traslado al centro especializado, esto permite la necrosis del tejido y el síndrome compartimental, daño que amerita ejecutar la fasciotomía, desbridamiento y drenaje de abscesos para evitar la amputación. Es el primer reporte de fasciotomía tras mordedura de Bothrops asper en el estado Lara. El traslado inmediato del paciente para un tratamiento específico con antiveneno, sigue siendo la principal medida para evitar casos graves de envenenamiento y así disminuir la severidad de la sintomatología y la letalidad.
DOĞA TEMELLİ ETKİNLİKLERE KATILANLARIN İÇSEL MOTİVASYONLARI İLE GELECEKTEKİ DAVRANIŞSAL NİYETİ ARASINDAKİ İLİŞKİNİN BELİRLENMESİ
Authors: KARACAOĞLU Sila
Published: August 2021

Doğa temelli turizm pazarı turistlerin her geçen gün artan ilgileri ve talepleri doğrultusunda hızlı bir şekilde büyümektedir. Dolayısıyla, bireylerin doğa temelli etkinliklere katılım nedenleri ile beklentilerinin anlaşılmasının ve gelecekteki davranışlarının tahmin edilmesinin söz konusu pazarda yer alan çeşitli paydaşların kendini doğru konumlandırması ve uygun rekabet stratejileri geliştirebilmesi açısından önemli olduğu düşünülmektedir. Buradan hareketle çalışmanın iki temel amacı bulunmaktadır. Birinci amaç; doğa temelli etkinliklere katılanların içsel motivasyonlarının (rahatlama, sosyalleşme, heyecan, öz saygı ve kendini gerçekleştirme) davranışsal niyeti yordama durumunu tespit etmektir. İkinci amaç ise doğa temelli etkinliklere katılanların davranışsal niyetlerini etkileyen sosyo-demografik unsurların (yaş, cinsiyet, medeni durum, eğitim seviyesi ve hane halkının gelir durumu) belirlenmesidir. Bu amaçlardan hareketle yürütülen araştırma Eskişehir’de bulunan çeşitli doğa gruplarındaki 397 kişi ile 18 Haziran 2021-10 Temmuz 2021 tarihlerinde çevrim içi anket uygulaması ile gerçekleştirilmiştir. Araştırma sonuçları, doğa temelli etkinliklere katılan bireylerin gelecekteki davranışsal niyetini birden fazla içsel motivasyon unsurunun etkilediğini ortaya koymaktadır. Analizlerden elde edilen bulgular ‘‘rahatlama”, “sosyalleşme”, “öz saygı” ve “kendini gerçekleştirme’’ olmak üzere dört içsel motivasyon unsurunun davranışsal niyeti yordadığını; “heyecan”ın ise davranışsal niyetin anlamlı bir yordayıcısı olmadığını göstermektedir. Ayrıca, sosyo-demografik özellikler arasından sadece cinsiyet değişkeninin davranışsal niyeti etkilediği, erkek katılımcıların gelecekteki doğa temelli etkinliklere yönelik davranışsal niyetlerinin kadın katılımcılara göre daha yüksek olduğu bulgusuna da erişilmiştir.
Survival Outcomes and Prognostic Factors of Borderline Ovarian Tumors
Authors: Supreechaya Phansenee , Tantipalakorn Charuwan , Muangmool Tanarat , Charoenkwan Kittipat , Suprasert Prapaporn , Srisomboon Jatupol
Published: August 2021

Background and Objective: Borderline ovarian tumor (BOT) is a distinct but heterogeneous group of tumors defined by histopathology as atypical epithelial proliferation without stromal invasion. Women with BOT are usually younger than those with invasive carcinoma. This study aimed to evaluate the survival outcomes and prognostic factors of patients with BOT in a single institute in the northern region of Thailand. Methods: The medical records of patients with BOT who were treated at Chiang Mai University Hospital between January 1, 2008 and December 31, 2019 were reviewed. The survival outcomes were analyzed by the Kaplan-Meier method and prognostic factors were analyzed by univariate and multivariate approaches. Results: 168 patients with BOT were enrolled in the study. The median age was 48.8 years. At the median follow-up time of 25.4 months, 9 patients (5.3%) developed recurrence and 2 (1.1%) experienced progression to invasive carcinoma. The 5-year progression-free survival (PFS) and overall survival were 93.2% and 97.4%, respectively. By univariate analysis, advanced stage (p=0.02), tumor size smaller than 10 cm (p=0.03), conservative surgery (p=0.03), and bilateral tumors (p=0.07) were significantly associated with worse PFS. Hysterectomy was a protective factor for recurrence with the hazard ratio of 0.09 (95% CI, 0.01 – 0.77; p= 0.03). Cell types, pelvic lymphadenectomy, micro-invasion, and non-invasive peritoneal implant did not significantly affect PFS. By multivariate analysis, early stage (p=0.01), tumor size larger than 10 cm (p=0.04), and hysterectomy (p=0.03) were significantly associated with better survival. Conclusion: Patients with BOT had excellent survival outcomes. Tumor size of larger than 10 cm, early-stage disease, and hysterectomy were significant prognostic factors for better survival outcomes. Conservative surgery should be offered to patients who desire to preserve future fertility and long-term follow-up is needed to assure recurrence - free.
Cognitive versus virtual reality simulation for evaluation of technical skills in neurosurgery
Authors: Knafo Steven , Penet Nicolas , Gaillard Stephan , Parker Fabrice
Published: August 2021

OBJECTIVE

Simulation is gaining momentum as a new modality of medical training, particularly in acute care settings such as surgery. In the present study, the authors aimed to compare individual cognitive skills with manual abilities as assessed by virtual reality (VR) simulation among neurosurgical residents.

METHODS

Participants were asked to complete a multiple-choice questionnaire assessing their surgical abilities regarding three basic neurosurgical procedures (endoscopic third ventriculostomy, cranial meningioma, and lumbar laminectomy). They subsequently performed these same three procedures on a VR simulator (NeuroTouch).

RESULTS

The authors found that cognitive scores correlated with self-evaluation of surgical experience and autonomy. On the contrary, VR simulation, as assessed by NeuroTouch automated scoring, did not reflect participants’ cognitive or self-evaluation of their surgical proficiency.

CONCLUSIONS

The results of this study suggest that neurosurgical education should focus as much on cognitive simulation (e.g., careful planning and critical appraisal of actual procedures) as on VR training of visuomotor skills.
Study of comparative surgical exposure to the petroclival region using patient-specific, petroclival meningioma virtual reality models
Authors: Jean Walter C. , Yang Yang , Srivastava Aneil , Tai Alexander X. , Herur-Raman Aalap , Kim H. Jeffrey , Li Da , Wu Zhen
Published: August 2021

OBJECTIVE

Despite advancement of surgical techniques, the attachments of petroclival meningiomas near the central clival depression (CCD) remain difficult to visualize. With existing methods, the amount of tumor near the CCD that is inaccessible through various approaches cannot be compared. Tumors distort the brainstem, changing the size of the operative corridor for some but not all approaches; therefore, using cadavers with normal posterior fossae makes it impossible to compare different approaches to the tumor. The authors used virtual reality (VR) models created from the imaging data of patients to compare various surgical approaches that have otherwise been incomparable in previous studies.

METHODS

CT and MRI data obtained in 15 patients with petroclival meningiomas were used to create anatomically accurate 3D VR models. For each model, various surgical approaches were performed, and the surgical freedom to 6 targets of the regions were measured. Furthermore, portions of the tumor that were visually blocked by the brainstem or bony structures were segmented and recorded as blinded volumes for comparison.

RESULTS

The extended retrosigmoid approach generated excellent exposure of the petroclival region, but for most specimens, there was inaccessible tumor volume adjacent to the brainstem (mean 641.3 mm3, SE 161.8). In contrast, the brainstem sides of the tumors were well-visualized by all the transpetrosal approaches. The blinded volume of the tumor was largest for the retrolabyrinthine approach, and this was statistically significant compared with all other approaches (mean 2381.3 mm3, SE 185.4).

CONCLUSIONS

The authors performed a novel laboratory study by using patient CT and MRI data to generate 3D virtual models to compare surgical approaches. Since it is impossible to perform various approaches in separate surgeries in patients for comparison, VR represents a viable alternative for such comparative investigations.
Augmented reality head-mounted display–based incision planning in cranial neurosurgery: a prospective pilot study
Authors: Ivan Michael E. , Eichberg Daniel G. , Di Long , Shah Ashish H. , Luther Evan M. , Lu Victor M. , Komotar Ricardo J. , Urakov Timur M.
Published: August 2021

OBJECTIVE

Monitor and wand–based neuronavigation stations (MWBNSs) for frameless intraoperative neuronavigation are routinely used in cranial neurosurgery. However, they are temporally and spatially cumbersome; the OR must be arranged around the MWBNS, at least one hand must be used to manipulate the MWBNS wand (interrupting a bimanual surgical technique), and the surgical workflow is interrupted as the surgeon stops to “check the navigation” on a remote monitor. Thus, there is need for continuous, real-time, hands-free, neuronavigation solutions. Augmented reality (AR) is poised to streamline these issues. The authors present the first reported prospective pilot study investigating the feasibility of using the OpenSight application with an AR head-mounted display to map out the borders of tumors in patients undergoing elective craniotomy for tumor resection, and to compare the degree of correspondence with MWBNS tracing.

METHODS

Eleven consecutive patients undergoing elective craniotomy for brain tumor resection were prospectively identified and underwent circumferential tumor border tracing at the time of incision planning by a surgeon wearing HoloLens AR glasses running the commercially available OpenSight application registered to the patient and preoperative MRI. Then, the same patient underwent circumferential tumor border tracing using the StealthStation S8 MWBNS. Postoperatively, both tumor border tracings were compared by two blinded board-certified neurosurgeons and rated as having an excellent, adequate, or poor correspondence degree based on a subjective sense of the overlap. Objective overlap area measurements were also determined.

RESULTS

Eleven patients undergoing craniotomy were included in the study. Five patient procedures were rated as having an excellent correspondence degree, 5 had an adequate correspondence degree, and 1 had poor correspondence. Both raters agreed on the rating in all cases. AR tracing was possible in all cases.

CONCLUSIONS

In this small pilot study, the authors found that AR was implementable in the workflow of a neurosurgery OR, and was a feasible method of preoperative tumor border identification for incision planning. Future studies are needed to identify strategies to improve and optimize AR accuracy.
Efficacy of a virtual reality–based basic and clinical fused curriculum for clinical education on the lumbar intervertebral disc
Authors: Qi Fangfang , Gan Yixiang , Wang Shengwen , Tie Yizhe , Chen Jiewen , Li Chunhai
Published: August 2021

OBJECTIVE

Today, minimally invasive procedures have become mainstream surgical procedures. Percutaneous endoscopic transforaminal discectomy for lumbar disc herniation (LDH) requires profound knowledge of the laparoscopic lumbar anatomy. Immersive virtual reality (VR) provides three-dimensional patient-specific models to help in the process of preclinical surgical preparation. In this study, the authors investigated the efficacy of VR application in LDH for training orthopedic residents and postgraduates.

METHODS

VR images of the lumbar anatomy were created with immersive VR and mAnatomy software. The study was conducted among 60 residents and postgraduates. A questionnaire was developed to assess the effect of and satisfaction with this VR-based basic and clinical fused curriculum. The teaching effect was also evaluated through a postlecture test, and the results of the prelecture surgical examination were taken as baselines.

RESULTS

All participants in the VR group agreed that VR-based education is practical, attractive, and easy to operate, compared to traditional teaching, and promotes better understanding of the anatomical structures involved in LDH. Learners in the VR group achieved higher scores on an anatomical and clinical fusion test than learners in the traditional group (84.67 ± 14.56 vs 76.00 ± 16.10, p < 0.05).

CONCLUSIONS

An immersive VR-based basic and clinical fused curriculum can increase residents’ and postgraduates’ interest and support them in mastering the structural changes and complicated symptoms of LDH. However, a simplified operational process and more realistic haptics of the VR system are necessary for further surgical preparation and application.
Augmented reality navigation for cranial biopsy and external ventricular drain insertion
Authors: Skyrman Simon , Lai Marco , Edström Erik , Burström Gustav , Förander Petter , Homan Robert , Kor Flip , Holthuizen Ronald , Hendriks Benno H. W. , Persson Oscar , Elmi-Terander Adrian
Published: August 2021

OBJECTIVE

The aim of this study was to evaluate the accuracy (deviation from the target or intended path) and efficacy (insertion time) of an augmented reality surgical navigation (ARSN) system for insertion of biopsy needles and external ventricular drains (EVDs), two common neurosurgical procedures that require high precision.

METHODS

The hybrid operating room–based ARSN system, comprising a robotic C-arm with intraoperative cone-beam CT (CBCT) and integrated video tracking of the patient and instruments using nonobtrusive adhesive optical markers, was used. A 3D-printed skull phantom with a realistic gelatinous brain model containing air-filled ventricles and 2-mm spherical biopsy targets was obtained. After initial CBCT acquisition for target registration and planning, ARSN was used for 30 cranial biopsies and 10 EVD insertions. Needle positions were verified by CBCT.

RESULTS

The mean accuracy of the biopsy needle insertions (n = 30) was 0.8 mm ± 0.43 mm. The median path length was 39 mm (range 16–104 mm) and did not correlate to accuracy (p = 0.15). The median device insertion time was 149 seconds (range 87–233 seconds). The mean accuracy for the EVD insertions (n = 10) was 2.9 mm ± 0.8 mm at the tip with a 0.7° ± 0.5° angular deviation compared with the planned path, and the median insertion time was 188 seconds (range 135–400 seconds).

CONCLUSIONS

This study demonstrated that ARSN can be used for navigation of percutaneous cranial biopsies and EVDs with high accuracy and efficacy.
Holographic mixed-reality neuronavigation with a head-mounted device: technical feasibility and clinical application
Authors: Qi Ziyu , Li Ye , Xu Xinghua , Zhang Jiashu , Li Fangye , Gan Zhichao , Xiong Ruochu , Wang Qun , Zhang Shiyu , Chen Xiaolei
Published: August 2021

OBJECTIVE

The authors aimed to evaluate the technical feasibility of a mixed-reality neuronavigation (MRN) system with a wearable head-mounted device (HMD) and to determine its clinical application and accuracy.

METHODS

A semiautomatic registration MRN system on HoloLens smart glasses was developed and tested for accuracy and feasibility. Thirty-seven patients with intracranial lesions were prospectively identified. For each patient, multimodal imaging–based holograms of lesions, markers, and surrounding eloquent structures were created and then imported to the MRN HMD. After a point-based registration, the holograms were projected onto the patient's head and observed through the HMD. The contour of the holograms was compared with standard neuronavigation (SN). The projection of the lesion boundaries perceived by the neurosurgeon on the patient's scalp was then marked with MRN and SN. The distance between the two contours generated by MRN and SN was measured so that the accuracy of MRN could be assessed.

RESULTS

MRN localization was achieved in all patients. The mean additional time required for MRN was 36.3 ± 6.3 minutes, in which the mean registration time was 2.6 ± 0.9 minutes. A trend toward a shorter time required for preparation was observed with the increase of neurosurgeon experience with the MRN system. The overall median deviation was 4.1 mm (IQR 3.0 mm–4.7 mm), and 81.1% of the lesions localized by MRN were found to be highly consistent with SN (deviation < 5.0 mm). There was a significant difference between the supine position and the prone position (3.7 ± 1.1 mm vs 5.4 ± 0.9 mm, p = 0.001). The magnitudes of deviation vectors did not correlate with lesion volume (p = 0.126) or depth (p = 0.128). There was no significant difference in additional operating time between different operators (37.4 ± 4.8 minutes vs 34.6 ± 4.8 minutes, p = 0.237) or in localization deviation (3.7 ± 1.0 mm vs 4.6 ± 1.5 mm, p = 0.070).

CONCLUSIONS

This study provided a complete set of a clinically applicable workflow on an easy-to-use MRN system using a wearable HMD, and has shown its technical feasibility and accuracy. Further development is required to improve the accuracy and clinical efficacy of this system.
Development of an inside-out augmented reality technique for neurosurgical navigation
Authors: Dho Yun-Sik , Park Sang Joon , Choi Haneul , Kim Youngdeok , Moon Hyeong Cheol , Kim Kyung Min , Kang Ho , Lee Eun Jung , Kim Min-Sung , Kim Jin Wook , Kim Yong Hwy , Kim Young Gyu , Park Chul-Kee
Published: August 2021

OBJECTIVE

With the advancement of 3D modeling techniques and visualization devices, augmented reality (AR)–based navigation (AR navigation) is being developed actively. The authors developed a pilot model of their newly developed inside-out tracking AR navigation system.

METHODS

The inside-out AR navigation technique was developed based on the visual inertial odometry (VIO) algorithm. The Quick Response (QR) marker was created and used for the image feature–detection algorithm. Inside-out AR navigation works through the steps of visualization device recognition, marker recognition, AR implementation, and registration within the running environment. A virtual 3D patient model for AR rendering and a 3D-printed patient model for validating registration accuracy were created. Inside-out tracking was used for the registration. The registration accuracy was validated by using intuitive, visualization, and quantitative methods for identifying coordinates by matching errors. Fine-tuning and opacity-adjustment functions were developed.

RESULTS

ARKit-based inside-out AR navigation was developed. The fiducial marker of the AR model and those of the 3D-printed patient model were correctly overlapped at all locations without errors. The tumor and anatomical structures of AR navigation and the tumors and structures placed in the intracranial space of the 3D-printed patient model precisely overlapped. The registration accuracy was quantified using coordinates, and the average moving errors of the x-axis and y-axis were 0.52 ± 0.35 and 0.05 ± 0.16 mm, respectively. The gradients from the x-axis and y-axis were 0.35° and 1.02°, respectively. Application of the fine-tuning and opacity-adjustment functions was proven by the videos.

CONCLUSIONS

The authors developed a novel inside-out tracking–based AR navigation system and validated its registration accuracy. This technical system could be applied in the novel navigation system for patient-specific neurosurgery.
Virtual dissection of the real brain: integration of photographic 3D models into virtual reality and its effect on neurosurgical resident education
Authors: Roh Tae Hoon , Oh Ji Woong , Jang Chang Ki , Choi Seonah , Kim Eui Hyun , Hong Chang-Ki , Kim Se-Hyuk
Published: August 2021

OBJECTIVE

Virtual reality (VR) is increasingly being used for education and surgical simulation in neurosurgery. So far, the 3D sources for VR simulation have been derived from medical images, which lack real color. The authors made photographic 3D models from dissected cadavers and integrated them into the VR platform. This study aimed to introduce a method of developing a photograph-integrated VR and to evaluate the educational effect of these models.

METHODS

A silicone-injected cadaver head was prepared. A CT scan of the specimen was taken, and the soft tissue and skull were segmented to 3D objects. The cadaver was dissected layer by layer, and each layer was 3D scanned by a photogrammetric method. The objects were imported to a free VR application and layered. Using the head-mounted display and controllers, the various neurosurgical approaches were demonstrated to neurosurgical residents. After performing hands-on virtual surgery with photographic 3D models, a feedback survey was collected from 31 participants.

RESULTS

Photographic 3D models were seamlessly integrated into the VR platform. Various skull base approaches were successfully performed with photograph-integrated VR. During virtual dissection, the landmark anatomical structures were identified based on their color and shape. Respondents rated a higher score for photographic 3D models than for conventional 3D models (4.3 ± 0.8 vs 3.2 ± 1.1, respectively; p = 0.001). They responded that performing virtual surgery with photographic 3D models would help to improve their surgical skills and to develop and study new surgical approaches.

CONCLUSIONS

The authors introduced photographic 3D models to the virtual surgery platform for the first time. Integrating photographs with the 3D model and layering technique enhanced the educational effect of the 3D models. In the future, as computer technology advances, more realistic simulations will be possible.
Fully automatic brain tumor segmentation for 3D evaluation in augmented reality
Authors: Fick Tim , van Doormaal Jesse A. M. , Tosic Lazar , van Zoest Renate J. , Meulstee Jene W. , Hoving Eelco W. , van Doormaal Tristan P. C.
Published: August 2021

OBJECTIVE

For currently available augmented reality workflows, 3D models need to be created with manual or semiautomatic segmentation, which is a time-consuming process. The authors created an automatic segmentation algorithm that generates 3D models of skin, brain, ventricles, and contrast-enhancing tumor from a single T1-weighted MR sequence and embedded this model into an automatic workflow for 3D evaluation of anatomical structures with augmented reality in a cloud environment. In this study, the authors validate the accuracy and efficiency of this automatic segmentation algorithm for brain tumors and compared it with a manually segmented ground truth set.

METHODS

Fifty contrast-enhanced T1-weighted sequences of patients with contrast-enhancing lesions measuring at least 5 cm3 were included. All slices of the ground truth set were manually segmented. The same scans were subsequently run in the cloud environment for automatic segmentation. Segmentation times were recorded. The accuracy of the algorithm was compared with that of manual segmentation and evaluated in terms of Sørensen-Dice similarity coefficient (DSC), average symmetric surface distance (ASSD), and 95th percentile of Hausdorff distance (HD95).

RESULTS

The mean ± SD computation time of the automatic segmentation algorithm was 753 ± 128 seconds. The mean ± SD DSC was 0.868 ± 0.07, ASSD was 1.31 ± 0.63 mm, and HD95 was 4.80 ± 3.18 mm. Meningioma (mean 0.89 and median 0.92) showed greater DSC than metastasis (mean 0.84 and median 0.85). Automatic segmentation had greater accuracy for measuring DSC (mean 0.86 and median 0.87) and HD95 (mean 3.62 mm and median 3.11 mm) of supratentorial metastasis than those of infratentorial metastasis (mean 0.82 and median 0.81 for DSC; mean 5.26 mm and median 4.72 mm for HD95).

CONCLUSIONS

The automatic cloud-based segmentation algorithm is reliable, accurate, and fast enough to aid neurosurgeons in everyday clinical practice by providing 3D augmented reality visualization of contrast-enhancing intracranial lesions measuring at least 5 cm3. The next steps involve incorporation of other sequences and improving accuracy with 3D fine-tuning in order to expand the scope of augmented reality workflow.
Evaluation of the effect of standard neuronavigation and augmented reality on the integrity of the perifocal structures during a neurosurgical approach
Authors: Davidovic Alioucha , Chavaz Lara , Meling Torstein R. , Schaller Karl , Bijlenga Philippe , Haemmerli Julien
Published: August 2021

OBJECTIVE

Intracranial minimally invasive procedures imply working in a restricted surgical corridor surrounded by critical structures, such as vessels and cranial nerves. Any damage to them may affect patient outcome. Neuronavigation systems may reduce the risk of such complications. In this study, the authors sought to compare standard neuronavigation (NV) and augmented reality (AR)–guided navigation with respect to the integrity of the perifocal structures during a neurosurgical approach using a novel model imitating intracranial vessels.

METHODS

A custom-made box, containing crisscrossing hard metal wires, a hidden nail at its bottom, and a wooden top, was scanned, fused, and referenced for the purpose of the study. The metal wires and an aneurysm clip applier were connected to a controller, which counted the number of contacts between them. Twenty-three naive participants were asked to 1) use NV to define an optimal entry point on the top, perform the smallest craniotomy possible on the wooden top, and to use a surgical microscope when placing a clip on the nail without touching the metal wires; and 2) use AR to preoperatively define an ideal trajectory, navigate the surgical microscope, and then perform the same task. The primary outcome was the number of contacts made between the metal wires and the clip applier. Secondary outcomes were craniotomy size, and trust in NV and AR to help avoid touching the metal wires, as assessed by a 9-level Likert scale.

RESULTS

The median number of contacts tended to be lower with the use of AR than with NV (AR, median 1 [Q1: 1, Q3: 2]; NV, median 3 [Q1: 1, Q3: 6]; p = 0.074). The size of the target-oriented craniotomy was significantly lower with the use of AR compared with NV (AR, median 4.91 cm2 [Q1: 4.71 cm2, Q3: 7.55 cm2]; and NV, median 9.62 cm2 [Q1: 7.07 cm2; Q3: 13.85 cm2]). Participants had more trust in AR than in NV (the differences posttest minus pretest were mean 0.9 [SD 1.2] and mean −0.3 [SD 0.2], respectively; p < 0.05).

CONCLUSIONS

The results of this study show a trend favoring the use of AR over NV with respect to reducing contact between a clip applier and the perifocal structures during a simulated clipping of an intracranial aneurysm. Target-guided craniotomies were smaller with the use of AR. AR may be used not only to localize surgical targets but also to prevent complications associated with damage to structures encountered during the surgical approach.
Three-dimensional–printed marker–based augmented reality neuronavigation: a new neuronavigation technique
Authors: Yavas Gorkem , Caliskan Kadri Emre , Cagli Mehmet Sedat
Published: August 2021

OBJECTIVE

The aim of this study was to assess the precision and feasibility of 3D-printed marker–based augmented reality (AR) neurosurgical navigation and its use intraoperatively compared with optical tracking neuronavigation systems (OTNSs).

METHODS

Three-dimensional–printed markers for CT and MRI and intraoperative use were applied with mobile devices using an AR light detection and ranging (LIDAR) camera. The 3D segmentations of intracranial tumors were created with CT and MR images, and preoperative registration of the marker and pathology was performed. A patient-specific, surgeon-facilitated mobile application was developed, and a mobile device camera was used for neuronavigation with high accuracy, ease, and cost-effectiveness. After accuracy values were preliminarily assessed, this technique was used intraoperatively in 8 patients.

RESULTS

The mobile device LIDAR camera was found to successfully overlay images of virtual tumor segmentations according to the position of a 3D-printed marker. The targeting error that was measured ranged from 0.5 to 3.5 mm (mean 1.70 ± 1.02 mm, median 1.58 mm). The mean preoperative preparation time was 35.7 ± 5.56 minutes, which is longer than that for routine OTNSs, but the amount of time required for preoperative registration and the placement of the intraoperative marker was very brief compared with other neurosurgical navigation systems (mean 1.02 ± 0.3 minutes).

CONCLUSIONS

The 3D-printed marker–based AR neuronavigation system was a clinically feasible, highly precise, low-cost, and easy-to-use navigation technique. Three-dimensional segmentation of intracranial tumors was targeted on the brain and was clearly visualized from the skin incision to the end of surgery.
Real-time navigation guidance with intraoperative CT imaging for pedicle screw placement using an augmented reality head-mounted display: a proof-of-concept study
Authors: Yanni Daniel S. , Ozgur Burak M. , Louis Robert G. , Shekhtman Yevgenia , Iyer Rajiv R. , Boddapati Venkat , Iyer Asha , Patel Purvee D. , Jani Raja , Cummock Matthew , Herur-Raman Aalap , Dang Phuong , Goldstein Ira M. , Brant-Zawadzki Michael , Steineke Thomas , Lenke Lawrence G.
Published: August 2021

OBJECTIVE

Augmented reality (AR) has the potential to improve the accuracy and efficiency of instrumentation placement in spinal fusion surgery, increasing patient safety and outcomes, optimizing ergonomics in the surgical suite, and ultimately lowering procedural costs. The authors sought to describe the use of a commercial prototype Spine AR platform (SpineAR) that provides a commercial AR head-mounted display (ARHMD) user interface for navigation-guided spine surgery incorporating real-time navigation images from intraoperative imaging with a 3D-reconstructed model in the surgeon's field of view, and to assess screw placement accuracy via this method.

METHODS

Pedicle screw placement accuracy was assessed and compared with literature-reported data of the freehand (FH) technique. Accuracy with SpineAR was also compared between participants of varying spine surgical experience. Eleven operators without prior experience with AR-assisted pedicle screw placement took part in the study: 5 attending neurosurgeons and 6 trainees (1 neurosurgical fellow, 1 senior orthopedic resident, 3 neurosurgical residents, and 1 medical student). Commercially available 3D-printed lumbar spine models were utilized as surrogates of human anatomy. Among the operators, a total of 192 screws were instrumented bilaterally from L2–5 using SpineAR in 24 lumbar spine models. All but one trainee also inserted 8 screws using the FH method. In addition to accuracy scoring using the Gertzbein-Robbins grading scale, axial trajectory was assessed, and user feedback on experience with SpineAR was collected.

RESULTS

Based on the Gertzbein-Robbins grading scale, the overall screw placement accuracy using SpineAR among all users was 98.4% (192 screws). Accuracy for attendings and trainees was 99.1% (112 screws) and 97.5% (80 screws), respectively. Accuracy rates were higher compared with literature-reported lumbar screw placement accuracy using FH for attendings (99.1% vs 94.32%; p = 0.0212) and all users (98.4% vs 94.32%; p = 0.0099). The percentage of total inserted screws with a minimum of 5° medial angulation was 100%. No differences were observed between attendings and trainees or between the two methods. User feedback on SpineAR was generally positive.

CONCLUSIONS

Screw placement was feasible and accurate using SpineAR, an ARHMD platform with real-time navigation guidance that provided a favorable surgeon-user experience.
A systematic review of virtual reality for the assessment of technical skills in neurosurgery
Authors: Chan Justin , Pangal Dhiraj J. , Cardinal Tyler , Kugener Guillaume , Zhu Yichao , Roshannai Arman , Markarian Nicholas , Sinha Aditya , Anandkumar Anima , Hung Andrew , Zada Gabriel , Donoho Daniel A.
Published: August 2021

OBJECTIVE

Virtual reality (VR) and augmented reality (AR) systems are increasingly available to neurosurgeons. These systems may provide opportunities for technical rehearsal and assessments of surgeon performance. The assessment of neurosurgeon skill in VR and AR environments and the validity of VR and AR feedback has not been systematically reviewed.

METHODS

A systematic review following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines was conducted through MEDLINE and PubMed. Studies published in English between January 1990 and February 2021 describing the use of VR or AR to quantify surgical technical performance of neurosurgeons without the use of human raters were included. The types and categories of automated performance metrics (APMs) from each of these studies were recorded.

RESULTS

Thirty-three VR studies were included in the review; no AR studies met inclusion criteria. VR APMs were categorized as either distance to target, force, kinematics, time, blood loss, or volume of resection. Distance and time were the most well-studied APM domains, although all domains were effective at differentiating surgeon experience levels. Distance was successfully used to track improvements with practice. Examining volume of resection demonstrated that attending surgeons removed less simulated tumor but preserved more normal tissue than trainees. More recently, APMs have been used in machine learning algorithms to predict level of training with a high degree of accuracy. Key limitations to enhanced-reality systems include limited AR usage for automated surgical assessment and lack of external and longitudinal validation of VR systems.

CONCLUSIONS

VR has been used to assess surgeon performance across a wide spectrum of domains. The VR environment can be used to quantify surgeon performance, assess surgeon proficiency, and track training progression. AR systems have not yet been used to provide metrics for surgeon performance assessment despite potential for intraoperative integration. VR-based APMs may be especially useful for metrics that are difficult to assess intraoperatively, including blood loss and extent of resection.
Randomized study comparing 3D virtual reality and conventional 2D on-screen teaching of cerebrovascular anatomy
Authors: Greuter Ladina , De Rosa Adriana , Cattin Philippe , Croci Davide Marco , Soleman Jehuda , Guzman Raphael
Published: August 2021

OBJECTIVE

Performing aneurysmal clipping requires years of training to successfully understand the 3D neurovascular anatomy. This training has traditionally been obtained by learning through observation. Currently, with fewer operative aneurysm clippings, stricter work-hour regulations, and increased patient safety concerns, novel teaching methods are required for young neurosurgeons. Virtual-reality (VR) models offer the opportunity to either train a specific surgical skill or prepare for an individual surgery. With this study, the authors aimed to compare the spatial orientation between traditional 2D images and 3D VR models in neurosurgical residents or medical students.

METHODS

Residents and students were each randomly assigned to describe 4 aneurysm cases, which could be either 2D images or 3D VR models. The time to aneurysm detection as well as a spatial anatomical description was assessed via an online questionnaire and compared between the groups. The aneurysm cases were 10 selected patient cases treated at the authors’ institution.

RESULTS

Overall, the time to aneurysm detection was shorter in the 3D VR model compared to 2D images, with a trend toward statistical significance (25.77 ± 37.26 vs 45.70 ± 51.94 seconds, p = 0.052). No significant difference was observed for residents (3D VR 24.47 ± 40.16 vs 2D 33.52 ± 56.06 seconds, p = 0.564), while in students a significantly shorter time to aneurysm detection was measured using 3D VR models (26.95 ± 35.39 vs 59.16 ± 44.60 seconds, p = 0.015). No significant differences between the modalities for anatomical and descriptive spatial mistakes were observed. Most participants (90%) preferred the 3D VR models for aneurysm detection and description, and only 1 participant (5%) described VR-related side effects such as dizziness or nausea.

CONCLUSIONS

VR platforms facilitate aneurysm recognition and understanding of its spatial anatomy, which could make them the preferred method compared to 2D images in the years to come.
The effect of augmented reality on the accuracy and learning curve of external ventricular drain placement
Authors: Van Gestel Frederick , Frantz Taylor , Vannerom Cédric , Verhellen Anouk , Gallagher Anthony G. , Elprama Shirley A. , Jacobs An , Buyl Ronald , Bruneau Michaël , Jansen Bart , Vandemeulebroucke Jef , Scheerlinck Thierry , Duerinck Johnny
Published: August 2021

OBJECTIVE

The traditional freehand technique for external ventricular drain (EVD) placement is most frequently used, but remains the primary risk factor for inaccurate drain placement. As this procedure could benefit from image guidance, the authors set forth to demonstrate the impact of augmented-reality (AR) assistance on the accuracy and learning curve of EVD placement compared with the freehand technique.

METHODS

Sixteen medical students performed a total of 128 EVD placements on a custom-made phantom head, both before and after receiving a standardized training session. They were guided by either the freehand technique or by AR, which provided an anatomical overlay and tailored guidance for EVD placement through inside-out infrared tracking. The outcome was quantified by the metric accuracy of EVD placement as well as by its clinical quality.

RESULTS

The mean target error was significantly impacted by either AR (p = 0.003) or training (p = 0.02) in a direct comparison with the untrained freehand performance. Both untrained (11.9 ± 4.5 mm) and trained (12.2 ± 4.7 mm) AR performances were significantly better than the untrained freehand performance (19.9 ± 4.2 mm), which improved after training (13.5 ± 4.7 mm). The quality of EVD placement as assessed by the modified Kakarla scale (mKS) was significantly impacted by AR guidance (p = 0.005) but not by training (p = 0.07). Both untrained and trained AR performances (59.4% mKS grade 1 for both) were significantly better than the untrained freehand performance (25.0% mKS grade 1). Spatial aptitude testing revealed a correlation between perceptual ability and untrained AR-guided performance (r = 0.63).

CONCLUSIONS

Compared with the freehand technique, AR guidance for EVD placement yielded a higher outcome accuracy and quality for procedure novices. With AR, untrained individuals performed as well as trained individuals, which indicates that AR guidance not only improved performance but also positively impacted the learning curve. Future efforts will focus on the translation and evaluation of AR for EVD placement in the clinical setting.
Augmented reality–assisted roadmaps during periventricular brain surgery
Authors: Bernard Florian , Haemmerli Julien , Zegarek Gregory , Kiss-Bodolay Daniel , Schaller Karl , Bijlenga Philippe
Published: August 2021

Visualizing major periventricular anatomical landmarks intraoperatively during brain tumor removal is a decisive measure toward preserving such structures and thus the patient's postoperative quality of life. The aim of this study was to describe potential standardized preoperative planning using standard landmarks and procedures and to demonstrate the feasibility of using augmented reality (AR) to assist in performing surgery according to these “roadmaps.” The authors have depicted stepwise AR surgical roadmaps applied to periventricular brain surgery with the aim of preserving major cognitive function. In addition to the technological aspects, this study highlights the importance of using emerging technologies as potential tools to integrate information and to identify and visualize landmarks to be used during tumor removal.
Simulation of surgery for supratentorial gliomas in virtual reality using a 3D volume rendering technique: a poor man's neuronavigation
Authors: Gosal Jaskaran Singh , Tiwari Sarbesh , Sharma Tarunesh , Agrawal Mohit , Garg Mayank , Mahal Sayani , Bhaskar Suryanarayanan , Sharma Raghavendra Kumar , Janu Vikas , Jha Deepak Kumar
Published: August 2021

OBJECTIVE

Different techniques of performing image-guided neurosurgery exist, namely, neuronavigation systems, intraoperative ultrasound, and intraoperative MRI, each with its limitations. Except for ultrasound, other methods are expensive. Three-dimensional virtual reconstruction and surgical simulation using 3D volume rendering (VR) is an economical and excellent technique for preoperative surgical planning and image-guided neurosurgery. In this article, the authors discuss several nuances of the 3D VR technique that have not yet been described.

METHODS

The authors included 6 patients with supratentorial gliomas who underwent surgery between January 2019 and March 2021. Preoperative clinical data, including patient demographics, preoperative planning details (done using the VR technique), and intraoperative details, including relevant photos and videos, were collected. RadiAnt software was used for generating virtual 3D images using the VR technique on a computer running Microsoft Windows.

RESULTS

The 3D VR technique assists in glioma surgery with a preoperative simulation of the skin incision and craniotomy, virtual cortical surface marking and navigation for deep-seated gliomas, preoperative visualization of morbid cortical surface and venous anatomy in surfacing gliomas, identifying the intervenous surgical corridor in both surfacing and deep-seated gliomas, and pre- and postoperative virtual 3D images highlighting the exact spatial geometric residual tumor location and extent of resection for low-grade gliomas (LGGs).

CONCLUSIONS

Image-guided neurosurgery with the 3D VR technique using RadiAnt software is an economical, easy-to-learn, and user-friendly method of simulating glioma surgery, especially in resource-constrained countries where expensive neuronavigation systems are not readily available. Apart from cortical sulci/gyri anatomy, FLAIR sequences are ideal for the 3D visualization of nonenhancing diffuse LGGs using the VR technique. In addition to cortical vessels (especially veins), contrast MRI sequences are perfect for the 3D visualization of contrast-enhancing high-grade gliomas.