Transsulcal parafascicular approach for resection of a brain metastasis using a syringe-based tubular system: a technical video demonstration

Objective To study the microsurgical modality for lateral ventricular meningiomas with neuronavigation and tubular retractor system and evaluate its long term outcome. Methods The clinical and follow-up data of 23 lateral ventricular meningioma patients during the past 3 years were collected for a retrospective analysis in our center. 12 patients used neuronavigation and tubular brain retractor system, 11 patients received traditional manual measurement anatomic landmarks with traditional brain retractor. The tumor resection extent, overall survival, recurrence, operation exposure, operation trauma, peri-operative complications and? post-operative quality of life were compared between two groups. Results The total tumor resection was achieved at 100% in both groups and the perioperative death or tumor recurrence within the follow-up period was not observed in both groups. The overall survival rate achieved 100%. Neuronavigation combined with tubular brain retractor technology did not increase the overall complications(P=0.414), nor decrease the operative field exposure(P=0.667). Its utility did not extend the operation time(P=0.695), but reduced the occurrence of aphasia and hemianopia after operation and significantly shortened the length of incision(P=0.034), the size of craniotomy(P=0.021) , the cortical incision length(P=0.001)and the days of hospitalization(P=0.037). Importantly, neuronavigation with tubular brain retractor system could significantly improve the postoperative quality of life for lateral ventricular meningioma patients(KPS, P=0.029). Conclusions Neuronavigation and tubular brain retractor system used in microsurgical resection of lateral ventricular meningioma doesn't decrease the total tumor resection and the operation exposure, but reduced intra-operative brain trauma and peri-operation complications. For the improvement of post-operative quality of life, it was suitable for lateral ventricular meningiomas. Key words: Neuronavigation; Lateral ventricl; Meningioma; Microsurgery

Minimally Invasive Surgical Outcomes for Deep-Seated Brain Lesions Treated with Different Tubular Retraction Systems: A Systematic Review and Meta-Analysis

Brain retraction systems are frequently required to achieve surgical exposure of deep-seated brain lesions. Spatula-based systems can be associated with injury to the cortex and deep white matter, particularly adjacent to the sharp edges, which can result in uneven pressure on the parenchyma over the course of a long operation. The use of tubular retractor systems has been proposed as a method to overcome these limitations. There have been no studies assessing the degree of brain injury associated with the use of tubular retractors. METHODS :Twenty patients were retrospectively identified at Weill Cornell Medical College who underwent resection of deep-seated brain lesions between 2005 and 2014 with the aid of a METRx tubular retractor system. Using the Brainlab software, pre- and postoperative images were analyzed to assess volume, depth, extent of resection, and change in postoperative MR FLAIR hyperintensity and restricted diffusion on diffusion-weighted imaging (DWI). The mean preoperative tumor volume was 16.25 ± 17.6 cm(3). Gross-total resection was achieved in 75%, near-total resection in 10%, and subtotal resection in 15% of patients. There was a small but not statistically significant increase in average FLAIR hyperintensity volume by 3.25 ± 10.51 cm(3) (p = 0.16). The average postoperative volume of DWI high signal area with restricted diffusion on apparent diffusion coefficient maps was 8.35 ± 3.05 cm(3). Assuming that the volume of restricted diffusion on DWI around tumor was 0 preoperatively, this represented a statistically significant increase on DWI (p < 0.001). Although tubular retractors do not appear to significantly increase FLAIR signal in the brain, DWI intensity around the retractors can be identified. These data indicate that although tubular retractors may minimize damage to surrounding tissues, they still cause cytotoxic edema and cellular damage. Objective comparison against other retraction methods, as compared by 3D volumetric analysis or similar methods, will be important in determining the true advantage of tubular retractor systems.

INTRODUCTION: The tubular retractor system in neurosurgery has commonly been used as a minimally invasive approach for spinal surgeries. Recently studies have reported their use in adult and pediatric cranial tumor resection. In this study, we sought to analyze our experience and outcomes in pediatric cranial tumor resections using a tubular retractor system. METHODS: A retrospective study was conducted to identify and analyze all children who underwent resection of cranial tumors using a tubular retractor system. Perioperative data included patient demographics, pre-operative presentation, pathology details, extent of resection, post-operative complications, and long-term outcomes. RESULTS: 21 patients were identified (10 male, 11 female) with a mean age of 10.1 years (1 year – 24 years). Most patients (15, 71.4%) achieved gross-total resections; 3 (14.3%) were near-total; and 2 (9.5%) were biopsies. Of the 21 patients, six had only one immediate post-operative complication, while patients two had two immediate post-operative complications. These included six with muscle weakness, one with hypopituitarism, and two with visual deficits. In addition, the average estimated blood loss was 105 mL, and the average length of stay was 4.14 days. The 30- and 90-day readmission rates and number of re-do resections were zero. On follow-up, 20 regularly followed-up with no worsening of post-operative complications, while only one was lost to follow-up. CONCLUSIONS: The utilization of the tubular retractor system in pediatric cranial tumor resection surgery is an effective retraction technique to decrease both strain on the brain and blood loss depending on the location of the pathology. In addition, it has practical application in possibly achieving higher rates of gross-total resection, avoiding post-operative complications, decreasing readmission rates, and preventing re-do resection surgeries.

Introduction/PurposeVascular malformations in the subcortical and/or periventricular regions can cause devastating intraventricular/intracranial hemorrhages (IVH/ICH). These lesions are typically reached via open surgical techniques requiring significant cortical brain retraction to establish...

Tubular retractor system as a minimally invasive surgery (MIS) technique has many advantages over other conventional MIS techniques. It offers direct visualization of the operative field, anatomical familiarity to spine surgeons, and minimizing tissue trauma. With technical advancement, many spinal pathologies are being treated using this system. Namely, herniated discs, lumbar and cervical stenosis, synovial cysts, lumbar instability, trauma, and even some intraspinal tumors have all been treated through tubular retractor system. Flexible arm and easy change of the tube direction are particularly useful in contralateral spinal decompression from an ipsilateral approach. Careful attention to surgical technique through narrow space will ensure that complications are minimized and will provide improved outcomes. However, understanding detailed anatomies and keeping precise surgical orientation are essential for this technique. Authors present the technical feasibility and initial results of use a tubular retractor system as a minimally invasive technique for variaties of spinal disorders with a review of literature.

Deep-seated supratentorial intraparenchymal and intraventricular brain lesions can be difficult to access without causing significant trauma to the overlying cortex and intervening white matter tracts. Traditional brain retractors use multiple blades, which do not exert pressure in an equally distributed fashion. Tubular retractors offer an advantage. Although a commercially available frame-based tubular retractor system is on the market (COMPASS; Compass, Inc., Rochester, MN), we modified existing off-the-shelf equipment at our institution into a frameless tubular brain retractor. We used 14- to 22-mm METRx (Medtronic, Minneapolis, MN) tubular retractors in combination with a frameless stereotactic navigation system to remove 10 deep lesions. Histological findings included 6 periventricular metastases, 1 insular glioblastoma multiforme, 1 periventricular glioblastoma multiforme, 1 intraventricular meningioma, and 1 hippocampal cavernous malformation. Radiographic gross total resection was achieved in all patients. One patient experienced a transient worsening of an existing preoperative Wernicke's aphasia; otherwise, there were no intra- or postoperative complications. One patient with radiographic gross total resection of a metastatic lesion experienced a local recurrence of disease, requiring stereotactic radiosurgery. A frameless stereotactic tubular retractor system for deep brain lesions can be assembled with equipment already available at many institutions. Use of this system can decrease incision and craniotomy size, decrease retractor-induced trauma to overlying cortex, and help prevent damage to underlying white matter tracts.

To improve the technique of placement of large plate electrodes for spinal cord stimulation with a minimally invasive approach using the METRx tubular retractor system (Medtronic Sofamor Danek, Minneapolis, MN). This dilating system splits the paravertebral musculature, avoiding the need to strip these muscles from the spine. The technique described makes it possible to perform the procedure (currently, it is most frequently performed using general anesthesia) with local anesthesia and sedation, allowing test stimulation, and with little intraoperative or postoperative discomfort for the patient. The tubular retractor system was used to approach the spine at the desired level using local anesthesia. A small laminectomy was performed through the working tube, and the plate electrodes were introduced by the same approach. Test stimulation could be performed to determine the correct electrode position because only local anesthesia was used. Seven patients were scheduled for placement of large plate electrodes for spinal cord stimulation. In six patients, with different indications for the placement of spinal cord stimulation, the electrode could be placed using the minimally invasive tubular retractor system approach with local anesthesia and slight sedation. A good test stimulation was obtained in all of the patients, resulting in good pain relief after definitive implantation. We were not able to perform the procedure in one patient because we could not reach the spinal canal at the level operated on previously. All patients experienced only acceptable postoperative back pain. Using a tubular retractor system, implantation of plate electrodes for spinal cord stimulation can be performed under local anesthesia with acceptable discomfort for the patient, making the approach of the spinal canal minimally invasive. This method allows test stimulation to assess the correct electrode position and results in less local postoperative discomfort because of the small-muscle splitting approach.

Worldwide, high rise construction is recent trend in the building development. Steel has many advantages which includes flexible framing system, assembling, less weight to height ratio, high availability and it doesn’t harm environment. That’s the reason steel has been mostly used material in the high rise buildings. Previously gravity load was considered as an important factor in the construction design. With the demand of high rise buildings now seismic force and lateral force is also gaining more attention. In High rise buildings tubular frames are most commonly used structural system. Among this framed and bundled are most famous tubular frame systems. Precise analysis is required for its design. Tubular systems are used in exterior as well as interior, mainly for resisting seismic force and lateral force. In this research Framed tube system and bundled tube system is analysed for lateral load resistance using ETABS software. For analysis purpose 8 stories steel building was considered. Different factors like lateral displacement at top floor, base shear, storey drift and steel weight were analysed for framed and bundled tubular system.

Worldwide, high rise construction is recent trend in the building development. Steel has many advantages which includes flexible framing system, assembling, less weight to height ratio, high availability and it doesn’t harm environment. That’s the reason steel has been mostly used material in the high rise buildings. Previously gravity load was considered as an important factor in the construction design. With the demand of high rise buildings now seismic force and lateral force is also gaining more attention. In High rise buildings tubular frames are most commonly used structural system. Among this framed and bundled are most famous tubular frame systems. Precise analysis is required for its design. Tubular systems are used in exterior as well as interior, mainly for resisting seismic force and lateral force. In this research Framed tube system and bundled tube system is analysed for lateral load resistance using ETABS software. For analysis purpose 8 stories steel building was considered. Different factors like lateral displacement at top floor, base shear, storey drift and steel weight were analysed for framed and bundled tubular system.

Worldwide, high rise construction is recent trend in the building development. Steel has many advantages which includes flexible framing system, assembling, less weight to height ratio, high availability and it doesn’t harm environment. That’s the reason steel has been mostly used material in the high rise buildings. Previously gravity load was considered as an important factor in the construction design. With the demand of high rise buildings now seismic force and lateral force is also gaining more attention. In High rise buildings tubular frames are most commonly used structural system. Among this framed and bundled are most famous tubular frame systems. Precise analysis is required for its design. Tubular systems are used in exterior as well as interior, mainly for resisting seismic force and lateral force. In this research Framed tube system and bundled tube system is analysed for lateral load resistance using ETABS software. For analysis purpose 8 stories steel building was considered. Different factors like lateral displacement at top floor, base shear, storey drift and steel weight were analysed for framed and bundled tubular system.

Minimally invasive surgery with tubular retractor system for deep-seated or intraventricular brain tumors: Report of 13 cases and technique description

Background: Osteoid osteomas are benign primary bone tumors with a predilection for posterior elements of the spinal column. Complete surgical excision through a traditional open approach is the treatment of choice for patients not responding to non-steroidal anti-inflammatory medications and patients with contraindications for nidus ablation. The study aims to highlight an alternative minimally invasive technique for complete surgical excision of osteoid osteoma encroaching into the spinal canal. Methods: We report a case of 22 years-old obese male suffering from left S1 radiculopathy and night pain. Magnetic resonance imaging and computed tomography (CT)-scan of the lumbosacral region revealed a benign bony lesion of size 13 mm × 11 mm × 8 mm encroaching from S1 lamina into the spinal canal and compressing left S1 root. Peri-lesional bony sclerosis and soft tissue edema were absent. In view of obesity and a small size of the lesion, it was decided to remove the lesion with a tubular retractor system under general anesthesia. Complete resection of the lesion was carried out sparing the L5-S1 facet, with a minimally invasive approach. Results: Patient had complete symptomatic improvement after the surgery. Histopathology showed interconnected trabeculae of woven bone matrix rimmed by osteoclasts consistent with the diagnosis of osteoid osteoma. Post-operative CT scan showed that the nidus was removed completely and important structures such as facet, pedicle, and midline posterior ligament complex were preserved. The patient resumed his daily activities and remained symptoms-free at the end of 6 months of follow-up. Conclusion: Minimally invasive surgery using a tubular retractor system can be safe and effective alternative to traditional open surgery for excision of osteoid osteoma from the posterior elements. Faster recovery, minimal tissue damage, and early return to work are added advantages for an obese patient undergoing minimally invasive total surgical excision. Keywords: Benign bone tumors, Sacral spine, Osteoid osteoma, Periosteal osteoid osteoma, Minimally invasive spine surgery, Tubular retractor system

Standard surgical procedures for the treatment of far cranio-lateral or foraminally extruded lumbar disc herniations include interlaminar exposure with partial or complete resection of the upper hemilamina and sometimes partial removal of the facet joint and weakening of the pars interarticularis. We present our experiences with the translaminar approach to this entity of lumbar disc herniation using a tubular retractor system. Fifteen patients with far cranio-laterally extruded disc herniations underwent neurosurgical intervention using a translaminar approach. The paraspinal muscles were spread with a dilatator after performing a 1.5 cm skin incision. A 16 mm METRx tubular retractor system (Medtronic Sofamor Danek, Memphis, TN) was directly placed on the upper lamina. The next steps were performed through this channel using the surgical microscope. A small ovoid fenestration (10x5 mm) was performed using a high speed drill and the disc prolapse was removed in a standard manner. Follow-ups were routinely carried out 3 weeks postoperatively and reassessment was subsequently carried out by telephone inquiry 10 to 44 months (median 23 months) after treatment. These results were rated according to the modified MacNab criteria. Five of the fifteen affected discs were at the level L3/4, eight at L4/5 and two at L5/S1. The average surgical time was 55 minutes. No complications occurred. In all patients sciatic pain disappeared immediately after the operation. One patient underwent fusion of the affected level one year later because of progression of a pre-existent pseudospondylolisthesis. Long-term follow-up demonstrated excellent results in six, good results in seven, a fair result in one and a poor result in one patient according to the modified MacNab criteria. The translaminar approach in conjunction with a tubular retractor system seems to be an effective and safe alternative technique for treating the small entity of far cranio- laterally or foraminally extruded lumbar disc herniations. It combines the advantages of a blunt muscle-spreading approach that produces little damage to the soft tissues, and the avoidance of large bone removal that may jeopardize vertebral stability. Since this approach does not permit sufficient exploration of the intervertebral disc space of origin, it should be limited to patients without significant bulging of the disc itself.

Hemorrhagic subcortical vascular lesions such as cavernous malformations (CM) and arteriovenous malformations (AVM) can be neurologically devastating. Conventional open surgical resection is often associated with additional morbidity. The BrainPath® (NICO Corp.) transsulcal tubular retractor system offers a less-invasive corridor to deep-seated lesions. Our objective was to describe a single-center experience with the resection of subcortical hemorrhagic vascular lesions in adult and pediatric patients using the BrainPath® system. The departmental database was queried for patients who underwent resection of a hemorrhagic CM, AVM, or cerebral aneurysm through the BrainPath® tubular retractor system between January 2017 and September 2021. All patients underwent either postoperative MRI (for patients with CM) or digital subtraction angiography (for patients with AVM or aneurysm). Demographic and clinical characteristics, preoperative and postoperative imaging features, operative details, and surgical and clinical outcomes were extracted through a retrospective review of the medical records. Fourteen patients (mean [SD] age 32.3 [23.9] years; 7 (50%) female) underwent BrainPath®-based resection of a deeply seated CM (n = 7), AVM (n = 6), or ruptured cerebral aneurysm (n = 1). The mean maximal lesion diameter was 21.5 (12.6) mm. The mean operative time was 134 (53) minutes. Residual lesion was present in 2 patients, both of which underwent repeat BrainPath®-assisted surgery for complete resection. All lesions were completely resected or obliterated on postoperative MRI or digital subtraction angiography. At a mean follow-up of 4.1 (1.1) years, the median modified Rankin Scale score was 1 (range 0-6). In a well-selected cohort, we show the effective use of BrainPath® tubular retractors for resection or obliteration of subcortical hemorrhagic vascular lesions. This report further exemplifies the expanded role of the endoport system beyond that of intracerebral hemorrhage and tumor. Further study will elucidate the impact of this less-invasive brain retraction technique on clinical outcome in patients with vascular lesions.