Raney clip left behind the titanium mesh after cranial surgery: Case report.

RATIONALE: Raney clips are commonly used in neurosurgical procedures to hold the scalp in place and stop bleeding during surgery. The removal of Raney clips is often the last process during cranial surgery prior to the closure of skin incision. Thus, a Raney clip found underneath the titanium mesh resulting in fever is a very rare occurrence. PATIENT CONCERNS: An 18-year-old male patient underwent cranial surgery due to intracranial abscess in the frontal lobe and subsequently underwent frontal skull repair using titanium mesh during which a Raney clip was unintentional left underneath the titanium mesh resulting in fever. DIAGNOSIS: A thin-slice computed tomography (CT) scan was used to identify the Raney clip. INTERVENTION: A third surgery was performed to remove the Raney clip. OUTCOMES: The patient fever total resolved after the third surgery with no further neurological deficits and 2-years follow-up revealed the patient is well and go about his daily activities. LESSONS: It is crucial to ensure that all foreign objects are removed after the surgery by counting all instruments used at and after each step during the operation, including all Raney clips. This will help prevent complications and ensure the safety as well as the well-being of the patient.

Origami-inspired soft fluidic actuation for minimally invasive large-area electrocorticography.

Electrocorticography is an established neural interfacing technique wherein an array of electrodes enables large-area recording from the cortical surface. Electrocorticography is commonly used for seizure mapping however the implantation of large-area electrocorticography arrays is a highly invasive procedure, requiring a craniotomy larger than the implant area to place the device. In this work, flexible thin-film electrode arrays are combined with concepts from soft robotics, to realize a large-area electrocorticography device that can change shape via integrated fluidic actuators. We show that the 32-electrode device can be packaged using origami-inspired folding into a compressed state and implanted through a small burr-hole craniotomy, then expanded on the surface of the brain for large-area cortical coverage. The implantation, expansion, and recording functionality of the device is confirmed in-vitro and in porcine in-vivo models. The integration of shape actuation into neural implants provides a clinically viable pathway to realize large-area neural interfaces via minimally invasive surgical techniques.

Accessing the Porcine Brain via High-Speed Pneumatic Drill Craniectomy.

The use of pigs as an experimental animal model is especially relevant in neuroscience research, as the porcine and human central nervous systems (CNS) share many important functional and architectural properties. Consequently, pigs are expected to have an increasingly important role in future research on various neurological diseases. Here, a method to perform an anterior craniectomy through the porcine frontal bone is described. After a midline incision and subsequent exposure of the porcine frontal bone, anatomical landmarks are used to ensure the optimal location of the craniectomy. By careful and gradual thinning of the frontal bone with a rounded drill, a rectangular opening to the dura mater and underlying cerebral hemispheres is achieved. The presented method requires certain surgical materials, including a pneumatic high-speed drill, and some degree of surgical experience. Potential complications include unintended lesions of the dura mater or dorsal sagittal sinus. However, the method is simple, time-efficient, and offers a high degree of reproducibility for researchers. If performed correctly, the technique exposes a large portion of the unaffected pig brain for various neuromonitoring or analyses.

Intraoperative lateral rectus electromyographic recordings optimized by deep intraorbital needle electrodes.

OBJECTIVE: We demonstrate the advantages and safety of long, intraorbitally-placed needle electrodes, compared to standard-length subdermal electrodes, when recording lateral rectus electromyography (EMG) during intracranial surgeries. METHODS: Insulated 25 mm and uninsulated 13 mm needle electrodes, aimed at the lateral rectus muscle, were placed in parallel during 10 intracranial surgeries, examining spontaneous and stimulation-induced EMG activities. Postoperative complications in these patients were reviewed, alongside additional patients who underwent long electrode placement in the lateral rectus. RESULTS: In 40 stimulation-induced recordings from 10 patients, the 25 mm electrodes recorded 6- to 26-fold greater amplitude EMG waveforms than the 13 mm electrodes. The 13 mm electrodes detected greater unwanted volume conduction upon facial nerve stimulation, typically exceeding the amplitude of abducens nerve stimulation. Except for one case with lateral canthus ecchymosis, no clinical or radiographic complications occurred in 36 patients (41 lateral rectus muscles) following needle placement. CONCLUSIONS: Intramuscular recordings from long electrode in the lateral rectus offers more reliable EMG monitoring than 13 mm needles, with excellent discrimination between abducens and facial nerve stimulations, and without significant complications from needle placement. SIGNIFICANCE: Long intramuscular electrode within the orbit for lateral rectus EMG recording is practical and reliable for abducens nerve monitoring.

Evaluation of a Wearable AR Platform for Guiding Complex Craniotomies in Neurosurgery.

Today, neuronavigation is widely used in daily clinical routine to perform safe and efficient surgery. Augmented reality (AR) interfaces can provide anatomical models and preoperative planning contextually blended with the real surgical scenario, overcoming the limitations of traditional neuronavigators. This study aims to demonstrate the reliability of a new-concept AR headset in navigating complex craniotomies. Moreover, we aim to prove the efficacy of a patient-specific template-based methodology for fast, non-invasive, and fully automatic planning-to-patient registration. The AR platform navigation performance was assessed with an in-vitro study whose goal was twofold: to measure the real-to-virtual 3D target visualization error (TVE), and assess the navigation accuracy through a user study involving 10 subjects in tracing a complex craniotomy. The feasibility of the template-based registration was preliminarily tested on a volunteer. The TVE mean and standard deviation were 1.3 and 0.6 mm. The results of the user study, over 30 traced craniotomies, showed that 97% of the trajectory length was traced within an error margin of 1.5 mm, and 92% within a margin of 1 mm. The in-vivo test confirmed the feasibility and reliability of the patient-specific template for registration. The proposed AR headset allows ergonomic and intuitive fruition of preoperative planning, and it can represent a valid option to support neurosurgical tasks.

Single-Surgeon in Vivo Experience with the Zeiss QEVO Microinspection Tool: An Analysis of Its Use for Extending the Reach of Operative Visualization.

The operating microscope is a foundational tool in modern neurosurgery. Operating microscopes serve increasingly as the lynchpin for highly sophisticated visualization platforms incorporating many complementary technologies. The Zeiss QEVO microinspection tool is a 45-degree viewing endoscopic instrument integrated into the Zeiss KINEVO 900 operating microscope (Carl Zeiss AG, Oberkochen, Germany). The QEVO tool enables surgeons to "look around the corners" of the surgical field to optimize visualization within tight operative corridors. In this article, we document our experience using the QEVO microinspection tool in a series of complex cranial neurosurgery procedures. This report focuses on the handling, visualization, and overall utility of the QEVO tool for achieving optimal visualization in deep cranial corridors.

Burr-Hole Evacuation of an Acute Epidural Hematoma using the Artemis Neuroevacuation Device With Flexible Endoscopic Visualization: 2-Dimensional Operative Video.

Minimally invasive (MIS) endoscopic burr-hole evacuation of both acute and subacute subdural hematomas (SDHs) has been demonstrated as a way to avoid large craniotomies and additional morbidity, particularly for patients who are poor surgical candidates.1,2 Although generally safe and effective, there are risks of complications including SDH recurrence or new hemorrhage including epidural hematoma (EDH).3,4 Acute intraparenchymal hemorrhage has also been successfully treated using MIS endoscopic techniques with the assistance of aspiration devices; however, acute EDHs generally still necessitate a craniotomy for evacuation, nullifying many of the advantages of burr-hole craniostomy.5,6 In this surgical video, we demonstrate-to our knowledge-the first case of endoscopic burr-hole evacuation of an acute EDH using an Artemis Neuro Evacuation device (Penumbra, Alameda, CA). We present the case of a 40 year-old man with a left anterior middle cranial fossa arachnoid cyst who developed a traumatic left subacute SDH and hemorrhage into the cyst. He underwent burr-hole craniostomy for endoscopic evacuation of subacute SDH, evacuation of hemorrhage within the cyst, and fenestration of arachnoid cyst. On postoperative day 2, he developed an acute left EDH with midline shift. An Artemis device was inserted into 1 of the pre-existing burr-holes and used to evacuate the acute EDH with direct visualization from a flexible endoscope inserted into the second burr-hole. The patient did well, was discharged 2 days later, and demonstrated complete resolution of hemorrhage 5 weeks post-procedure. The video also provides a brief background on arachnoid cysts, their association with hemorrhage, and MIS techniques for hemorrhage evacuation.7-12 There is no identifying information in the video. The patient provided informed consent for both procedures (Video 1).

A Preliminary Study on Animal Experiments of Robot-Assisted Craniotomy.

BACKGROUND: Traditional craniotomy relies on the surgeon's experience and can be complicated owing to excessive skull bone removal, undesirable brain tissue penetration, or severe bleeding. For craniotomy, we developed a robot system based on intraoperative cone-beam computed tomography image guidance and human-robot cooperative interaction, aiming to improve the safety and accuracy of surgery and reduce the labor-intensiveness of the procedure. METHODS: Intraoperative cone-beam computed tomography image guidance was adopt to improve the accuracy in our experiment. Craniotomy was performed using an interactive method based on human-robot collaboration, which could achieve a natural interactive method in accordance with surgeons' operating habits. The frequency-based method of contact distinction and the method of torque estimation were used to improve the safety of the designed robot. RESULTS: An animal experiment was conducted to verify the effectiveness of the robot system. During the drilling process, the position error was 0.92 ± 0.17 mm (upper surface) and 0.97 ± 0.11 mm (lower surface), and the angle error was 3.37 ± 1.43°. During the milling process, the position error was 1.06 ± 0.13 mm (upper surface) and 1.09 ± 0.09 mm (lower surface). The results showed that the system had sufficient precision and could better complete craniotomy with human-robot collaboration. In addition, with the feedback of multisensor information, the robot system could achieve a sufficient level of safety. CONCLUSIONS: The robot system can achieve accurate positioning and safe user-friendly human-robot interaction, which solves problems encountered in the drilling and milling of craniotomy, meets clinical needs, and provides a new method for robot-assisted craniotomy.

Long-Term Neurocognitive Outcomes of Spring-Assisted Surgery versus Cranial Vault Remodeling for Sagittal Synostosis.

BACKGROUND: A long-term neurocognitive comparison of patients with sagittal synostosis who underwent spring-assisted surgery or cranial vault remodeling has not been performed. METHODS: Patients with sagittal synostosis who underwent spring-assisted surgery or cranial vault remodeling were recruited from Wake Forest School of Medicine and Yale School of Medicine, respectively. Cognitive tests administered included an abbreviated intelligence quotient, academic achievement, and visuomotor integration. An analysis of covariance model compared cohorts controlling for demographic variables. RESULTS: Thirty-nine spring-assisted surgery and 36 cranial vault remodeling patients were included in the study. No significant differences between cohorts were found with respect to age at surgery, sex, race, birth weight, family income, or parental education. The cranial vault cohort had significantly older parental age (p < 0.001), and mean age at testing for the spring cohort was significantly higher (p = 0.001). After adjusting for covariates, the cranial vault cohort had significantly higher verbal intelligence quotient (116.5 versus 104.3; p = 0.0024), performance intelligence quotient (109.2 versus 101.5; p = 0.041), and full-scale intelligence quotient (114.3 versus 103.2; p = 0.0032). When included patients were limited to intelligence quotients from 80 to 120, the cranial vault cohort maintained higher verbal (108.0 versus 100.4; p = 0.036), performance (104.5 versus 97.7; p = 0.016), and full-scale (107.6 versus 101.5; p = 0.038) intelligence quotients. The cranial vault cohort had higher visuomotor integration scores than the surgery group (111.1 versus 98.1; p < 0.001). There were no significant differences in academic achievement. CONCLUSIONS: Sagittal synostosis patients who underwent cranial vault remodeling had higher intelligence quotient and visuomotor integration scores. There were no differences in academic achievement. Both cohorts had intelligence quotient scores at or above the normal range. Further studies are warranted to identify factors that may contribute to cognitive outcome differences. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, II.

Complications following titanium cranioplasty compared with nontitanium implants cranioplasty: A systematic review and meta-analysis.

Decompressive craniectomy is widely used to treat medically refractory intracranial hypertension. There were still few studies focusing on the complications between titanium cranioplasty with non-titanium materials cranioplasty. Our systematic review and meta-analysis aimed to assess the complications following titanium cranioplasty and to make a comparison with nontitanium materials. A systematic review was used to review titanium cranioplasty characters in recent articles. A systematic literature review and meta-analysis were performed by using PubMed/MEDLINE, Scopus, the Cochrane databases and Embase for studies reporting on cranioplasty procedures that compared complication outcomes between titanium with non-titanium materials. The final 15 studies met inclusion criteria and represented 2258 cranioplasty procedures (896 titanium, 1362 nontitanium materials). Overall complications included surgical site infection, hematoma, implant exposure, seizure, cerebrospinal fluid leak, imprecise fitting. Titanium cranioplasty was associated with a significant decrease in overall complications rate (OR, 0.72; P = 0.007), hematoma rate (OR, 0.31; P = 0.0003) and imprecise fitting rate (OR, 0.35; P = 0.04). However, it also suggested that titanium cranioplasty can be greatly increased implant exposure rate (OR, 4.11; P < 0.00001). Our results confirmed the advantages of titanium cranioplasty in reducing complications including hematoma, imprecise fitting, and also suggested that clinicians should pay more attention to postoperative implant exposure. With new synthetic materials emerging, it would also be interesting to study the cost-effect and functional outcomes associated with cranioplasty materials.

A novel omnidirectional tin-alloyed ring retractor for craniotomy in neurosurgery: technical note.

In neurosurgical operations, proper craniotomy using retractors is necessary. Various surgical instruments are used for this purpose, including standard retractors and multipurpose head frame retractor systems. However, the conventional multipurpose head frame system is often not optimal for use in some craniotomies and postures because of its size and complexity of setting. We have invented a new omnidirectional tin-alloyed (ODT) ring retractor for craniotomy with malleability and shape memory characteristics to resolve these issues. It is principally elliptical in shape, approximately 30 × 20 cm in diameter, and sufficiently firm. Accordingly, this ODT ring can retract the surgical field in all directions. Here, we report our experiences of 281 neurosurgical craniotomies using this ODT ring retractor system in various craniotomy sites and postures. Our novel ODT ring retractor is useful because of its low profile, multidirectional retractability, and less obstructiveness with its malleability. It could be used with pediatric patients where strong traction is not desirable.

Flexible endoscopic assistance in the surgical management of vestibular schwannomas.

Endoscopic-assisted techniques have extensively been applied to vestibular schwannoma (VS) surgery allowing to increase the extent of resection, minimize complications, and preserve facial nerve and auditory functions. In this paper, we retrospectively analyze the effectiveness of flexible endoscope in the endoscopic-assisted retrosigmoid approach for the surgical management of VS of various sizes. The authors conducted a retrospective analysis on 32 patients who underwent combined microscopic and flexible endoscopic resection of VS of various sizes over a period of 16 months. Flexible endoscopic-assisted retrosigmoid approach was performed in all cases, and in 6 cases, flexible and rigid endoscopic control were used in combination to evaluate the differences between the two surgical instruments. The surgical results were additionally compared with a previous case series of 141 patients operated for VS of various sizes without endoscopic assistance. Gross-total resection was achieved in 84% of the cases and near-total resection was accomplished in the rest of them. Excellent or good facial nerve function was observed in all except one case with a preoperative severe facial palsy. Hearing preservation surgery (HPS) was attempted in 11 cases and accomplished in 9 (81.8%). A tumor remnant was endoscopically identified in the fundus of the IAC in all cases (100%). Endoscopic assistance increased the rate of total removal and no intrameatal residual tumor was seen at radiological follow-up. Comparative analysis with a surgical cohort of patients operated with the sole microsurgical technique showed a significative association between endoscopic assistance and intracanalicular extent of resection. Combined microsurgical and flexible endoscopic assistance provides remarkable advantages in the pursuit of maximal safe resection of VS and preservation of facial nerve and auditory functions, minimizing the risk of post-operative complications.

A simple and effective modified technique of twist drill craniostomy for bedside drainage and irrigation of chronic subdural hematoma: Technical and clinical study.

OBJECTIVE: Chronic subdural hematoma (CSDH) is an important health problem observed mostly in elderly population. Here, we aimed to describe and validate a simple modified technique of twist-drill craniostomy (TDC) using easily accessible tools for effective and safe bedside CSDH drainage. METHODS: A detailed description of the new modified TDC technique which allows for sequential drainage and irrigation under physiological conditions is provided. Clinical and radiological characteristics as well as surgical results of the patients undergoing this procedure are also presented. RESULTS: A total of 55 patients (30 M, 25 F) underwent this modified TDC. Mean age was 61.7 ±â€¯12.3 years. Medical comorbidities were common (76.4 %). Subdural hematoma was mostly unilateral (83.6 %). Maximum width of hematoma was 21 ±â€¯4 mm on average (range: 9-38 mm). In total, patients underwent 1.6 ±â€¯0.9 subdural tappings on average (median: 1, range: 1-5). Repeat tappings were performed in 43.6 % of the patients. No mortality, serious morbidity or infectious complications were noted. Pneumocephalus was either absent or minimal in most cases (96.4 %). Mean length of hospital stay was 4.9 ±â€¯4.0 days (median: 3; range: 2-20 days). The clinical outcomes were favorable in 92.7 % of the patients (no craniotomy required and no symptomatic recurrence detected). CONCLUSION: This modified technique of TDC utilizes easily available tools, yields satisfactory radiological and clinical results, allows repeated tappings even in outpatient settings and can thus be readily applied in every neurosurgical unit across the world. It can be an effective alternative to existing procedures for patients with multiple co-morbidities and/or high anesthesia risk, in emergency conditions and busy neurosurgical centers.

Microsurgical clipping of multiple cerebral aneurysms in the acute phase of aneurysmal subarachnoid hemorrhage through a minipterional approach: The Chilean experience.

OBJECTIVE: The minipterional craniotomy (MPTc) has been widely accepted as a minimally invasive alternative to the pterional approach for the treatment of certain small non-ruptured anterior circulation aneurysms. The aim of this study was to determine the effectiveness and safety of the MPTc in the context of a complex and potentially harmful scenario: acute onset of subarachnoid hemorrhage (SAH) in patients harboring multiple intracranial aneurysms (MIA). METHODS: Patients harboring MIA clipped through a unilateral MPTc were selected from four retrospective databases of four high-volume neurosurgical centers. Patients with a Hunt & Hess score 4 or 5 were not considered candidates for clipping through a MPTc. Medical records and radiological images were retrospectively reviewed. Epidemiological, clinical and radiological data, as well as short-term outcome (modified Rankin scale at 6 month-follow-up) were analyzed. RESULTS: 16 patients harboring 33 aneurysms (16 ruptured, 17 non ruptured) met the inclusion criteria. Each aneurysm size was 5.7 ± 2.1 mm (range 3-11). 12 out of 33 aneurysms were located in the middle cerebral artery (MCA). Anterior communicating (ACom) and MCA aneurysms were the aneurysm locations most commonly ruptured (5 each, 62 %). Complete occlusion was achieved in 32 aneurysms (97 %) and near-complete occlusion in 1 (3%). 13 patients (93 %) were independent at 6 month-follow-up. Mortality rate was 0%. Complications included 1 cerebrospinal-fluid leakage. CONCLUSION: When indicated (Hunt Hess < 4), performing a MPTc is safe and effective in aSAH cases with multiple aneurysms.

Bedside Craniostomy and Serial Aspiration with an Intraosseous Drill/Needle to Temporize an Acute Epidural Hemorrhage with Mass Effect.

BACKGROUND: This report describes a technique for an immediate mechanical intervention using a familiar tool for emergency physicians and trauma surgeons to temporize acute epidural bleeding with mass effect. The Monro-Kellie Doctrine suggests that immediate removal of some blood will reduce intracranial pressure and mitigate some of the deleterious effects until the neurosurgeon can respond. CASE DESCRIPTION: A 38-year-old male with active extradural hemorrhage and expanding hemtoma with mass effect and herniation was treated at the bedside with an intraosseous drill to perform craniostomy and allow serial aspirations of continued bleeding. CONCLUSIONS: Bedside craniosotmy with an intraosseous drill can allow for immediate temporizing of a large epidural hemorrhage and be applied by emergency physicians and/or trauma specialists when neurosurgical consultation is delayed. Serial aspirations should be performed when hemorrhage is ongoing and until definitive evacuation is performed.

The craniotomy box: an innovative method of containing hazardous aerosols generated during skull saw use in autopsy on a COVID-19 body.

During a disease pandemic, there is still a requirement to perform postmortem examinations within the context of legal considerations. The management of the dead from COVID-19 should not impede the medicolegal investigation of the death where required by the authorities and legislation but additional health and safety precautions should be adopted for the necessary postmortem procedures. The authors have therefore used the craniotomy box in an innovative way to enable a safe alternative for skull and brain removal procedures on suspected or confirmed COVID-19 bodies. The craniotomy box technique was tested on a confirmed COVID-19 positive body where a full postmortem examination was performed by a team of highly trained personnel in a negative pressure Biosafety Level 3 (BSL-3) autopsy suite in the National Institute of Forensic Medicine (IPFN) Malaysia. This craniotomy box is a custom-made transparent plastic box with five walls but without a floor. Two circular holes were made in one wall for the placement of arms in order to perform the skull opening procedure. A swab to detect the presence of the SARS-CoV-2 virus was taken from the interior surface of the craniotomy box after the procedure. The result from the test using real-time reverse transcriptase polymerase chain reaction (rRT-PCR) proved that an additional barrier provided respiratory protection by containing the aerosols generated from the skull opening procedure. This innovation ensures procedures performed inside this craniotomy box are safe for postmortem personnel performing high risk autopsies during pandemics.

Assembly and operation of an open-source, computer numerical controlled (CNC) robot for performing cranial microsurgical procedures.

Cranial microsurgery is an essential procedure for accessing the brain through the skull that can be used to introduce neural probes that measure and manipulate neural activity. Neuroscientists have typically used tools such as high-speed drills adapted from dentistry to perform these procedures. As the number of technologies available for neuroscientists has increased, the corresponding cranial microsurgery procedures to deploy them have become more complex. Using a robotic tool that automatically performs these procedures could standardize cranial microsurgeries across neuroscience laboratories and democratize the more challenging procedures. We have recently engineered a robotic surgery platform that utilizes principles of computer numerical control (CNC) machining to perform a wide variety of automated cranial procedures. Here, we describe how to adapt, configure and use an inexpensive desktop CNC mill equipped with a custom-built surface profiler for performing CNC-guided microsurgery on mice. Detailed instructions are provided to utilize this 'Craniobot' for performing circular craniotomies for coverslip implantation, large craniotomies for implanting transparent polymer skulls for cortex-wide imaging access and skull thinning for intact skull imaging. The Craniobot can be set up in <2 weeks using parts that cost <$1,500, and we anticipate that the Craniobot could be easily adapted for use in other small animals.