The Use of BrainPath Tubular Retractors in the Management of Deep Brain Lesions: A Review of Current Studies

O-ARM navigation in tubular retractor-assisted minimal invasive parafascicular approach: technical note

Trans-sulcal minimally invasive parafascicular surgery is an emerging technique to approach deep lesions with minimal brain retraction. Localization of the tubular retractor during surgery is critical, and intraoperative magnetic resonance imaging and neuronavigation present limitations. We describe the intraoperative use of O-Arm® coupled with pre-operative tractography to precisely localize the tubular retractor. With air acting as contrast, the tubular retractor was localized in three dimensions, without any additional disruption to white matter tracts or nearby vascular structures. We conclude that visualization of tubular retractor using an intraoperative computerized tomography scan is a safe and feasible adjunct in resection of deep lesions via a minimally invasive approach.

Minimally invasive resection of intracranial lesions using tubular retractors: A single surgeon series

OBJECTIVE

Tubular retractors are increasingly used due to their low complication rates, providing easier access to lesions while minimizing trauma from brain retraction. Our study presents the most extensive series of cases performed by a single surgeon aiming to assess the effectiveness and safety of a transcortical-transtubular approach for removing intracranial lesions.

METHODS

We performed a retrospective review of patients who underwent resection of an intracranial lesion with the use of tubular retractors. Electronic medical records were reviewed for patient demographics, preoperative clinical deficits, diagnosis, preoperative and postoperative magnetic resonance imaging (MRI) scans, lesion characteristics including location, volume, extent of resection (EOR), postoperative complications, and postoperative deficits.

RESULTS

112 transtubular resections for intracranial lesions were performed. Patients presented with a diverse number of pathologies including metastasis (31.3 %), GBM (21.4 %), and colloid cysts (19.6 %) The mean pre-op lesion volume was 14.45 cm3. A gross total resection was achieved in 81 (71.7 %) cases. Seventeen (15.2 %) patients experienced early complications which included confusion, short-term memory difficulties, seizures, meningitis and motor and visual deficits. Four (3.6 %) patients had permanent complications, including one with aphasia and difficulty finding words, another with memory loss, a third with left-sided weakness, and one patient who developed new-onset long-term seizures. Mean post-operative hospitalization length was 3.8 days.

CONCLUSION

Tubular retractors provide a minimally invasive approach for the extraction of intracranial lesions. They serve as an efficient tool in neurosurgery, facilitating the safe resection of deep-seated lesions with minimal complications.

A comparison of brain retraction mechanisms using finite element analysis and the effects of regionally heterogeneous material properties

Finite element (FE) simulations of the brain undergoing neurosurgical procedures present us with the great opportunity to better investigate, understand, and optimize surgical techniques and equipment. FE models provide access to data such as the stress levels within the brain that would otherwise be inaccessible with the current medical technology. Brain retraction is often a dangerous but necessary part of neurosurgery, and current research focuses on minimizing trauma during the procedure. In this work, we present a simulation-based comparison of different types of retraction mechanisms. We focus on traditional spatulas and tubular retractors. Our results show that tubular retractors result in lower average predicted stresses, especially in the subcortical structures and corpus callosum. Additionally, we show that changing the location of retraction can greatly affect the predicted stress results. As the model predictions highly depend on the material model and parameters used for simulations, we also investigate the importance of using region-specific hyperelastic and viscoelastic material parameters when modelling a three-dimensional human brain during retraction. Our investigations demonstrate how FE simulations in neurosurgical techniques can provide insight to surgeons and medical device manufacturers. They emphasize how further work into this direction could greatly improve the management and prevention of injury during surgery. Additionally, we show the importance of modelling the human brain with region-dependent parameters in order to provide useful predictions for neurosurgical procedures.

Endoscopic Cylinder Surgery for Ventricular Lesions

Cylinder retractors have been developed to reduce the risk of brain retraction injury during surgery by dispersing retraction pressure on the brain. In recent years, various types of cylinder retractors have been developed and widely used in neurosurgery. The ventricles, being deep structures within the brain, present an effective area for cylinder retractor utilization. Endoscopy provides a bright, wide field of view in the deep surgical field, even through narrow corridors.This chapter introduces surgical techniques using an endoscope through a cylinder. Given the deep and complex shapes of the ventricles, preoperative planning is paramount. Two main surgical techniques are employed in endoscopic cylinder surgery. The wet-field technique involves the continuous irrigation of artificial cerebrospinal fluid (CSF) during the procedure, maintaining ventricle shape with natural water pressure, facilitating tumor border identification, and achieving spontaneous hemostasis. Conversely, the dry-field technique involves CSF drainage, providing a clear visual field even during hemorrhage encounters. In intraventricular surgery, both techniques are used and switched as needed.Specific approaches for lateral, third, and fourth ventricular tumors are discussed, considering their locations and surrounding anatomical structures. Detailed intraoperative findings and strategies for tumor removal and hemostasis are presented.Endoscopic cylinder surgery offers a versatile and minimally invasive option for intraventricular tumors, leading to improved surgical outcomes. Overall, this technique enhances surgical precision and patient outcomes in intraventricular tumor cases.

Resection of an Intraventricular Metastatic Tumor with Minimally Invasive Port Technique: 2-Dimensional Operative Video

The use of minimally invasive port technology has been proposed as a safe method to reduce retractor-induced parenchymal injury, particularly for the resection of deep-seated lesions.1-6 A 69-year-old woman with a history of previous colon cancer surgery presented with gait disturbances and progressive headaches. Magnetic resonance imaging revealed a tumor involving the right ventricular atrium that appeared consistent with metastasis. A parieto-occipital craniotomy was performed on the basis of the preoperatively planned surgical trajectory (Video 1). After the dural incision, the arachnoid was opened down to the sulcus under visualization with microscope. Next, the ViewSite Brain Access system tubular retractor (VBAS; Vycor Medical Inc., Boca Raton, Florida, USA) was introduced toward the lesion under navigation guidance. Once the ventricular atrium was entered, the surface of the tumor came into view. It was coagulated and progressively debulked with ultrasonic aspirator. After the mass was adequately decompressed, a plane of dissection between the ependyma and the tumor could be developed with dynamic angulation of the port in order to allow better visualization. Finally, the tumor could be gently rolled away from the choroid plexus and removed. Meticulous hemostasis was achieved, and the tubular retractor was slowly removed. The patient recovered uneventfully without neurologic deficits on follow-up, and the postoperative magnetic resonance imaging evidenced a complete resection of the tumor. The video illustrates technical nuances and demonstrates the feasibility of minimal access port surgery for the resection of intraventricular lesions with low morbidity and mortality using microsurgical techniques. The patient consented to the publication of her image.

Minimally Invasive Surgery of Deep-Seated Brain Lesions Using Tubular Retractors and Navigated Transcranial Magnetic Stimulation-Based Diffusion Tensor Imaging Tractography Guidance: The Minefield Paradigm

BACKGROUND

Surgical treatment of deep-seated brain lesions is a major challenge for neurosurgeons. Recently, tubular retractors have been used to help neurosurgeons in achieving the targeting and resection of deep lesions.

OBJECTIVE

To describe a novel surgical approach based on the combination of tubular retractors and preoperative mapping by navigated transcranial magnetic stimulation (nTMS) and nTMS-based diffusion tensor imaging (DTI) tractography for the safe resection of deep-seated lesions.

METHODS

Ten consecutive patients affected by deep-seated brain lesions close to eloquent motor/language/visual pathways underwent preoperative nTMS mapping of motor/language cortical areas and nTMS-based DTI tractography of adjacent eloquent white matter tracts, including optic radiations. The nTMS-based information was used to plan the optimal surgical trajectory and to guide the insertion of tubular retractors within the brain parenchyma without causing injury to the eloquent cortical and subcortical structures. After surgery, all patients underwent a new nTMS-based DTI tractography of fascicles close to the tumor to verify their structural integrity.

RESULTS

Gross total resection was achieved in 8 cases, subtotal resection in 1 case, and a biopsy in 1 case. No new postoperative deficits were observed, except in 1 case where a visual field defect due to injury to the optic radiations occurred. Postoperative nTMS-based DTI tractography showed the integrity of the subcortical fascicles crossed by tubular retractors trajectory in 9 cases.

CONCLUSION

The novel strategy combining tubular retractors with functional nTMS-based preoperative mapping enables a safe microsurgical resection of deep-seated lesions through the preservation of eloquent cortical areas and subcortical fascicles, thus reducing the risk of new permanent deficits.

Practical, Stereotactic, Low-Profile Technique for Transcortical/Transventricular Colloid Cyst Removal Independent of Ventricular Size: Technical Note and Analysis of Approaches

BACKGROUND

In the presence of a dilated foramen of Monro, a transcortical, transforaminal approach is considered the safest and simplest approach for resection of colloid cysts. However, in the presence of small or normal frontal horns, numerous microsurgical approaches and, often complicated, variations have been described, invariably employing forms of stereotactic navigation.

OBJECTIVE

To report an alternative, accurate, microsurgical stereotactic low-profile technique.

METHODS

The small frontal horn is stereotactically targeted as previously described. Routine equipment is used to accurately create a novel, rigid, atraumatic surgical corridor.

RESULTS

After a 7-mm corticotomy, a peel-away catheter carrying the AxiEM stylet engages the target set as the frontal horn. All joints of the endoscope holder are locked, allowing only catheter advancement (y axis) while lateral (x axis) or anteroposterior (z axis) movements are secure. Two, 7-mm retractor blades are inserted. The extremely consistent anatomy of the foramen of Monro allows en bloc microsurgical removal without unnecessary coagulation of cyst wall or choroid plexus.

CONCLUSION

Despite a plethora of approaches to the rostral third ventricle, in the presence of normal or small frontal horns, including creation of transcallosal/interforniceal, suprachoroidal (or transchoroidal), and sub-choroidal, colloid cyst resection does not necessarily need to be convoluted. Technical nuances of an accurate, practical, minimally invasive technique are described.

Surgical Resection of Deep-Seated Arteriovenous Malformations Through Stereotactically Guided Tubular Retractor Systems: A Case Series

BACKGROUND

Arteriovenous malformations (AVMs) in the subcortical and/or periventricular regions can cause significant intraventricular and intracranial hemorrhage. These AVMs can pose a unique surgical challenge because traditional, open approaches to the periventricular region require significant cortical/white matter retraction to establish sufficient operative corridors, which may result in risk of neurological injury. Minimally invasive tubular retractor systems represent a novel, feasible surgical option for treating deep-seated AVMs.

OBJECTIVE

To explore 5 cases of NICO BrainPath-assisted resection of subcortical/periventricular AVMs.

METHODS

Five patients from a single institution were operated on for deep-seated AVMs using tubular retractor systems. Collected data included demographics, AVM specifications, preoperative neurological status, postoperative neurological status, and postoperative/intraoperative angiogram results.

RESULTS

Five patients, ranging from age 10 to 45 years, underwent mini-craniotomy for stereotactically guided tubular retractor-assisted AVM resection using neuronavigation for selecting a safe operative corridor. No preoperative embolization was necessary. Mean maximum AVM nidal diameter was 8.2 mm. All deep-seated AVMs were completely resected without complications. All AVMs demonstrated complete obliteration on intraoperative angiogram and on 6-month follow-up angiogram.

CONCLUSION

Minimally invasive tubular retractors are safe and present a promising surgical option for well-selected deep-seated AVMs. Furthermore, study may elucidate whether tubular retractors improve outcomes after microsurgical AVM resection secondary to mitigation of iatrogenic retraction injury risk.

Updates in intraoperative strategies for enhancing intra-axial brain tumor control

To ensure excellent postoperative clinical outcomes while preserving critical neurologic function, neurosurgeons who manage patients with intra-axial brain tumors can use intraoperative technologies and tools to achieve maximal safe resection. Neurosurgical oncology revolves around safe and optimal extent of resection, which further dictates subsequent treatment regimens and patient outcomes. Various methods can be adapted for treating both primary and secondary intra-axial brain lesions. We present a review of recent advances and published research centered on different innovative tools and techniques, including fluorescence-guided surgery, new methods of drug delivery, and minimally invasive procedural options.

Endoscopic Trans-Mini-Cylinder Biopsy for Intraparenchymal Brain Lesions

OBJECTIVE

The biopsy procedure is intended to obtain an adequate specimen volume from the targeted area while ensuring minimal damage to the normal brain. We performed navigation-guided endoscopic biopsy using a small-diameter cylinder to reduce the invasiveness of the biopsy procedure and ensure a sufficient amount of tissue is collected. We examined whether it is possible to reduce brain tissue injury by using a small-diameter cylinder and improve safety and effectiveness by using an endoscope to directly observe the lesion and achieve hemostasis.

METHODS

Patients who underwent endoscopic biopsy surgery using a 6-mm-diameter cylinder for intraparenchymal lesions were enrolled in this study. Postoperative hematoma formation and the extent of trajectory scarring were assessed.

RESULTS

Fifty-two procedures performed on 51 patients were analyzed in this study. Postoperative neurological deterioration was not observed in any patient. A pathological diagnosis was made for all patients. Postoperative computed tomography revealed no hematoma after 49 procedures and a small hematoma after 3 procedures, and no patients required additional treatment. A postoperative trajectory scar less than 5 mm in diameter was observed after 30 procedures, a scar of 5-10 mm was observed after 19 procedures, a scar larger than 10 mm was observed after 3 procedures at 1 week after surgery, and 40, 6 and 0 scars were observed at 3 months after surgery.

CONCLUSIONS

Endoscopic biopsy using a small-diameter cylinder is a possible alternative biopsy technique for intraparenchymal lesions. This surgical technique is useful, especially in patients at risk of hemorrhagic complications.

Wide Dissection Trans-Sulcal Approach for Resection of Deep Intra-Axial Lesions in Eloquent Brain Areas

Introduction: Resection of intra-axial tumors (IaT) in eloquent brain regions risks major postoperative neurological deficits. Awake craniotomy is often used to navigate these areas; however, some patients are ineligible for awake procedures. The trans-sulcal approach (TScal) was introduced to reduce parenchymal trauma during tumor resection. We report our experiences utilizing TScal for resection of deep IaT located in eloquent areas. Materials and Methods: This is a single-center retrospective analysis of patients who underwent IaT resection in eloquent areas via TScal from January 2013 to April 2021. Seventeen cases were reviewed, and relevant data was collected. Fluorescence-guided surgery with 5-aminolevulinic acid (ALA) and intraoperative ultrasound was performed in some cases. Results: Seventeen patients (10 males, 7 females) averaging 61.2 years-old (range, 21-76) were included in this study. Average length of stay was 4.8 days, and only 2 patients (11.8%) required hospital readmission within 30 days. Gross total resection (GTR) was achieved in 15 patients (88.2%), while subtotal resection occurred in 2 patients (11.8%). Eleven patients (64.7%) reported full resolution of symptoms, 4 patients (23.5%) reported deficit improvement, and 2 patients (11.8%) experienced no change from their preoperative deficits. No patient developed new permanent deficits postoperatively. Discussion: GTR, preoperative deficit reduction, and complications were comparable to awake craniotomy and other TScal studies. Ancillary intraoperative techniques, such as brain mapping, 5-ALA and intraoperative ultrasound, are afforded by TScal to improve resection rates and overall outcomes. Conclusions: TScal can be an option for patients with deep lesions in eloquent areas who are not candidates for awake surgeries.

Using the ROSA Robot for Lesion Resection: A Novel Adapter With Added Applications

BACKGROUND

The ROSA robot (Medtech) has been shown to be a useful instrument in the surgeon's armamentarium for accurate placement of stereotactic electroencephlography depth electrodes. However, it has not yet been used as a navigation tool for lesion resection. Here, we demonstrate a novel adapter that allows the surgeon to use the ROSA robot with the NICO BrainPath for the resection of deep lesions.

OBJECTIVE

To demonstrate the utility of an adapter that allows the ROSA robot to be used in conjunction with the NICO BrainPath tube for lesion resection.

METHODS

A stainless steel adapter was made based on the specifications of the ROSA pointer instrument. Two 3D printed models were used to undergo a "mock" surgery using the adapter to assess for ease of use and applicability.

RESULTS

The adapter allowed for adequate accessibility and visualization of the tumors in both mock cases. In addition, the stability of the ROSA robot and the design of the adapter allowed the surgeon to rest their hands on the instrument without jeopardizing its position.

CONCLUSION

The ROSA adapter allowed for accurate navigation and exposure of these lesions, combining the accuracy and stability of the ROSA robot, with the retraction of the BrainPath tube.

Minimally Invasive Surgery for Spontaneous Intracerebral Hematoma. Real-Life Implementation Model and Economic Estimation

Objective

Spontaneous intracerebral hemorrhage is characterized by high fatality outcomes, even under best medical treatment. Recently, minimally invasive surgical (MIS) evacuation of the hematoma has shown promising results and may soon be implemented in the clinical practice. Hereby, we intended to foresee the logistic requirements for an early hematoma evacuation protocol, as well as to evaluate in a real-life implementation model the cost-utility of the two main MIS techniques for hemorrhagic stroke (catheter evacuation plus thrombolysis and neuroendoscopic aspiration).

Methods

Data were obtained from the pool of hemorrhagic-stroke patients admitted to our institution during an annual period (2020-2021) and contrasted to the reported results in published trials of MIS techniques. Potential candidates for surgical treatment were identified according to the inclusion/exclusion criteria established in these trials. Then, a cost-utility analysis was performed, which explored the incremental cost per unit of health gained with a given treatment. The treatment effect was measured by differences in modified Rankin Score, and subsequently converted to quality-adjusted life years (QALY).

Results

Of the 137 patients admitted to our center with supratentorial spontaneous intracerebral hemorrhage in a 1-year period, 17 (12.4%) were potential candidates for the catheter evacuation plus thrombolysis technique (Minimally Invasive Surgery with Thrombolysis in Intracerebral Hemorrhage Evacuation trial, MISTIE III criteria) and 59 (43.0%) for the neuroendoscopic aspiration technique (Dutch Intracerebral Hemorrhage Surgery Trial Pilot Study, DIST criteria). The incremental cost-utility ratio was € 76,533.13 per QALY for the catheter-based evacuation and € 60,703.89 per QALY for the endoscopic-based technique.

Conclusion

Around 12-43% of patients admitted to hospital with spontaneous hemorrhagic stroke could be potential candidates to MIS early evacuation of the cerebral hematoma. In our real-life implementation model, the cost-utility analysis favored the neuroendoscopic evacuation over the catheter aspiration technique. Further studies are advisable as new data from the ongoing randomized trials becomes available.

Early Minimally Invasive Parafascicular Surgery for Evacuation of Spontaneous Intracerebral Hemorrhage in the Setting of Computed Tomography Angiography Spot Sign: A Case Series

BACKGROUND

Spontaneous intracerebral hemorrhage (sICH) is associated with high morbidity and mortality, and the role of surgery is uncertain. Spot sign on computed tomography angiography (CTA) has previously been seen as a contraindication for minimally invasive techniques.

OBJECTIVE

To demonstrate the use of minimally invasive parafascicular surgery (MIPS) for early evacuation of sICH in patients with spot sign on CTA.

METHODS

Retrospective review of patients presenting to a US tertiary academic medical center from 2018 to 2020 with sICH and CTA spot sign who were treated with MIPS within 6 h of arrival.

RESULTS

Seven patients (6 men and 1 woman, mean age 54.4 yr) were included in this study. There was a significant decrease between preoperative and postoperative intracerebral hemorrhage volumes (75.03 ± 39.00 cm3 vs 19.48 ± 17.81 cm3, P = .005) and intracerebral hemorrhage score (3.1 ± 0.9 vs 1.9 ± 0.9, P = .020). The mean time from arrival to surgery was 3.72 h (±1.22 h). The mean percentage of hematoma evacuation was 73.78% (±21.11%). The in-hospital mortality was 14.29%, and the mean modified Rankin score at discharge was 4.6 (±1.3). No complications related to the surgery were encountered in any of the cases, with no abnormal intraoperative bleeding and no pathology demonstrating occult vascular lesion.

CONCLUSION

Early intervention with MIPS appears to be a safe and effective means of hematoma evacuation despite the presence of CTA spot sign, and this finding should not delay early intervention when indicated. Intraoperative hemostasis may be facilitated by the direct visualization provided by a tubular retractor system.

Soft Robotic Deployable Origami Actuators for Neurosurgical Brain Retraction

Metallic tools such as graspers, forceps, spatulas, and clamps have been used in proximity to delicate neurological tissue and the risk of damage to this tissue is a primary concern for neurosurgeons. Novel soft robotic technologies have the opportunity to shift the design paradigm for these tools towards safer and more compliant, minimally invasive methods. Here, we present a pneumatically actuated, origami-inspired deployable brain retractor aimed at atraumatic surgical workspace generation inside the cranial cavity. We discuss clinical requirements, design, fabrication, analytical modeling, experimental characterization, and in-vitro validation of the proposed device on a brain model.

Establishing a standardized method for the effective intraoperative collection and biological preservation of brain tumor tissue samples using a novel tissue preservation system: A pilot study

Glioblastoma (GB) is an aggressive tumor exhibiting extensive inter- and intratumoral heterogeneity. Several possible reasons contribute to the historical inability to develop effective therapeutic strategies for treatment of GB. One such challenge is the inability to consistently procure high quality biologically preserved specimens for use in molecular research and patient derived xenograft (PDX) model development. Currently, no scientifically derived standardized method exists for intraoperative tissue collection specifically designed with the fragility of ribonucleic acid (RNA) in mind. In this investigation, we set out to characterize matched specimens from six GB patients comparing the traditional handling and collection processes of intraoperative tissue used in most neurosurgical operating rooms (ORs) versus an automated resection, collection, and biological preservation system (APS) which captures, preserves, and biologically maintains tissue in a prescribed and controlled microenvironment. Matched specimens were processed in parallel at various time points and temperatures, evaluating viability, RNA and protein concentrations, and isolation of GB cell lines. We found that APS-derived GB slices stored in an APS modified medium remained viable and maintained high quality RNA and protein concentration for up to 24 hours. Our results demonstrated that primary GB cell cultures derived in this manner had improved growth over widely used collection and preservation methods. By implementing an automated intraoperative system, we also eliminated inconsistencies in methodology of tissue collection, handling and biological preservation, establishing a repeatable and standardized practice that does not require additional staff or a lab technician to manage.

[Tubular retractors for transcranial approaches to intraaxial brain tumors in children]

Reduction of surgical trauma associated with approach to deep brain structures including resection of tumors is an urgent direction in development of techniques and technology.

OBJECTIVE

To analyze the efficacy and safety of tubular retractors in surgery of deep brain tumors in children.

MATERIAL AND METHODS

The study included 17 children with deep brain tumors who underwent surgery between 2020 and 2021. Tubular retractors were used in all cases. The control group consisted of 15 children with a similar disease and standard intraoperative tissue traction technique. All patients underwent MRI of the brain on the first postoperative day. We analyzed severity of traction-induced damage to brain tissue in T2 FLAIR and DWI images.

RESULTS

Clinical outcomes and structure of surgical complications were similar in both groups. Tubular retractor turned out to be a tool reducing traction injury. In the main group, postoperative MRI revealed significantly less damage to brain tissue along surgical approach in T2 (edema zone) and DWI (ischemic changes) images.

Use of the Image Guided Minimally Invasive BrainPath System to Evacuate Spontaneous Cerebellar Hemorrhages

BrainPath (NICO, Indianapolis, Indiana) is a tool that can be used to evacuate supratentorial hematomas due to spontaneous intracerebral hemorrhage (ICH). However, when ICH occurs in the posterior fossa, an open approach is often undertaken to evacuate the hematoma. The application of minimally invasive technology, while available, has not been well established. Our objective was to describe the use of the image-guided, minimally invasive BrainPath system to evacuate a spontaneous cerebellar hemorrhage. We present the case of a sixty-four-year-old male patient with a cerebellar hematoma due to hypertensive hemorrhage. The patient's medical record, including the history and physical, progress notes, operative notes, discharge summary, and imaging studies were reviewed to document the clinical presentation as well as the details of the operative technique and postoperative outcomes in this paper. We discuss the technical nuances of the operative points in detail. In our example case, the BrainPath system was successfully used to evacuate the cerebellar hematoma and no procedural-related complications occurred. The patient's recovery remained uncomplicated at three months of follow-up. In summary, the BrainPath system offers a less invasive alternative to open evacuation for cerebellar bleeds. 

A new simple and free tubular device for microscopic transcortical approach to deep-seated lesions: technical note and case example

BACKGROUND

Surgery for deep-seated brain tumors remains challenging. Transcortical approaches often require brain retraction to ensure an adequate surgical corridor, thus possibly leading to brain damage. Various techniques have been developed to minimize brain retraction such as self-retaining retractors, endoscopic approaches, or tubular retractor systems. Even if they evenly distribute the mechanical pressure over the parenchyma, rigid retractors can also cause some degree of brain damage and have significant disadvantages. We propose here a soft cottonoid retractor for microscopic resection of deep-seated and ventricular lesions.

METHODS

Through a small corticectomy, a channel route with a blunt cannula is developed until the lesion is reached. Then, a "balloon-like system" made with a surgical glove is progressively inflated, dilatating the surgical corridor. A mini-tubular device, handmade by suturing a surgical cottonoid, is positioned into the corridor, unfolded, and sutured to the edge of the dura, to prevent it from being progressively expelled from the working channel. This allows a good visualization of the lesion and surrounding structures under the microscope.

RESULTS

Advantages of this technique are the softness of the tube walls, the absence of rigid arm to hold the tube, and the possibility for the tube to follow the movements of the instruments and to modify its orientation according to the working area.

CONCLUSION

This simple and inexpensive tubular working channel for microscopic transcortical approach is a valuable alternative technique to traditional self-retaining retractor and rigid tube for the microsurgical resection of deep-seated brain tumors.

Minimally-invasive tubular retraction ports for intracranial neurosurgery: History and future perspectives

Brain retraction is a necessary yet potentially damaging requirement of accessing lesions located in deep structures. The development of minimally-invasive tubular retractors (MITRs) provides the theoretical advantage of maximizing visualization of and access to deep-seated lesions, all while minimizing collateral tissue damage. These advantages make MITRs preferable to traditional bladed retractors in the majority of deep-seated lesions. Several commercially-available MITR systems currently exist and have been shown to aid in achieving excellent outcomes with acceptable safety profiles. Nevertheless, important drawbacks to currently-available MITR systems exist. Continued pursuit of an ideal MITR system that provides maximal visualization and access to deep-seated lesions while minimizing retraction-related tissue damage is therefore important. In this review, we discuss the historical development of MITRs, the advantages of MITRs compared to traditional bladed retractors, and opportunities to improve the development of prospective MITRs.

Endoscopic versus Open Microsurgical Excision of Colloid Cysts: A Comparative Analysis and State-of-the-Art Review of Neurosurgical Techniques

BACKGROUND

The surgical approaches of colloid cysts commonly include endoscopy or open microsurgery. Each approach carries its own challenges, feasibility, and complications. The aim of the current study is to compare endoscopic versus open microsurgical excision of third ventricular colloid cysts.

METHODS

A retrospective cohort study was conducted to compare the surgical outcomes of endoscopic versus open microsurgical (transcortical-transventricular and transcallosal approaches) excision of colloid cyst of the third ventricle at a tertiary-care medical institute. All patients with a neuroradiologic diagnosis of colloid cyst who subsequently underwent surgical management between January 2003 and June 2020 were included. The neurologic outcome was assessed at the last follow-up visit.

RESULTS

A total of 32 patients with colloid cysts were included in the study. The mean age was 35.8 ± 18.3 years (range, 4-75 years). Female patients slightly outnumbered male patients (n = 17; 53.1%). A total of 21 patients (65.6%) underwent endoscopic resection of the colloid cyst. Complications were encountered in 7 patients (endoscopic, n = 3; microsurgery, n = 4; P = 0.151). Recurrence was identified in 4 patients (endoscopic, n = 3; microsurgery, n = 1; P = 0.673). Most patients improved neurologically on follow-up visits to the clinic (endoscopic, n = 19; microsurgery, n = 9; P = 0.482).

CONCLUSIONS

Both endoscopic and microsurgical approaches provide favorable surgical outcomes in colloid cyst resection. The complication rates between both approaches is statistically insignificant. The optimal surgical approach for colloid cyst resection remains controversial.

Minimally invasive trans-sulcal parafascicular surgical resection of cerebral tumors: translating anatomy to early clinical experience

The minimally invasive port-based trans-sulcal parafascicular surgical corridor (TPSC) has incrementally evolved to provide a safe, feasible, and effective alternative to access subcortical and intraventricular pathologies. A detailed anatomical foundation is important in mitigating cortical and white matter tract injury with this corridor. Thus, the aims of this study are (1) to provide a detailed anatomical construct and overview of TPSCs and (2) to translate an anatomical framework to early clinical experience. Based on regional anatomical constraints, suitable parafascicular entry points were identified and described. Fiber tracts at both minimal and increased risks for each corridor were analyzed. TPSC-managed cases for metastatic or primary brain tumors were retrospectively reviewed. Adult patients 18 years or older with Karnofsky Performance Status (KPS) ≥ 70 were included. Subcortical brain metastases between 2 and 6 cm or primary brain tumors between 2 and 5 cm were included. Patient-specific corridors and trajectories were determined using MRI-tractography. Anatomy: The following TPSCs were described and translated to clinical practice: superior frontal, inferior frontal, inferior temporal, intraparietal, and postcentral sulci. Clinical: Eleven patients (5 males, 6 females) were included (mean age = 52 years). Seven tumors were metastatic, and 4 were primary. Gross total, near total, and subtotal resection was achieved in 7, 3, and 1 patient(s), respectively. Three patients developed intraoperative complications; all recovered from their intraoperative deficits and returned to baseline in 30 days. A detailed TPSC anatomical framework is critical in conducting safe and effective port-based surgical access. This review may represent one of the few early translational TPSC studies bridging anatomical data to clinical subcortical and intraventricular surgical practice.