Volumetric analyses of ablation dimensions in microwave ablation for colorectal liver metastases.

BACKGROUND: In thermal ablation of malignant liver tumors, ablation dimensions remain poorly predictable. This study aimed to investigate factors influencing volumetric ablation dimensions in patients treated with stereotactic microwave ablation (SMWA) for colorectal liver metastases (CRLM). METHODS: Ablation volumes from CRLM ≤3 cm treated with SMWA within a prospective European multicentre trial were segmented. Correlations between applied ablation energies and resulting effective ablation volumes (EAV) and ablation volume irregularities (AVI) were investigated. A novel measure for AVI, including minimum enclosing and maximum inscribed ellipsoid ablation volumes, and a surrogate parameter for the expansion of ablation energy (EAV per applied energy), was introduced. Potential influences of tumor and patient-specific factors on EAV per applied energy and AVI were analyzed using multivariable mixed-effects models. RESULTS: A total of 116 ablations from 71 patients were included for analyses. Correlations of EAV or AVI and ablation energy were weak to moderate, with a maximum of 25% of the variability in EAV and 13% in AVI explained by the applied ablation energy. On multivariable analysis, ablation expansion (EAV per applied ablation energy) was influenced mainly by the tumor radius (B = -0.03, [CI -0.04, -0.007]). AVI was significantly larger with higher applied ablation energies (B = 0.002 [CI 0.0007, 0.002]]); liver steatosis, KRAS mutation, subcapsular location or proximity to major blood vessels had no influence. CONCLUSIONS: This study confirmed that factors beyond the applied ablation energy might affect volumetric ablation dimensions, resulting in poor predictability. Further clinical trials including tissue sampling are needed to relate physical tissue properties to ablation expansion.

Metastasis-directed stereotactic body radiotherapy for oligometastatic renal cell carcinoma: extent of tumor burden eradicated by radiotherapy.

PURPOSE: We aimed to explore whether complete eradication of tumor burden with stereotactic body radiotherapy (SBRT) would affect the outcomes of oligometastatic renal cell carcinoma (RCC). MATERIALS AND METHODS: Patients diagnosed with extracranial oligometastatic RCC (no more than five metastases) between 2007 and 2019 were reviewed. Those without nephrectomy were excluded. SBRT to all, some and no lesions were defined as complete, incomplete, and no SBRT. Progression-free survival (PFS) and cancer-specific survival (CSS) were analyzed using Kaplan-Meier method, Cox regression model and the Fine and Gray method. RESULT: A total of 101 patients were included, 51.5% of whom had < 3 metastases. Forty (39.6%) patients received complete SBRT, and 61 (60.4%) received no or incomplete SBRT. The 1-year LC rate was 97.3%. The complete SBRT group had significantly longer PFS (26.0 vs 18.8 months; p = 0.043) and CSS (not reached vs. 55.3 months; p = 0.012) compared with the no or incomplete SBRT group. In multivariate analysis, ECOG 0-1 (HR 0.389, 95% CI 0.167-0.906, p = 0.029) and complete SBRT were prognostic factors for CSS (HR 0.307, 95% CI 0.108-0.876, p = 0.027). Complete SBRT was associated with improved CSS in the subgroups of patients with age < 55 years, ECOG 0-1, clear-cell histology, IMDC intermediate/poor risk, metachronous metastasis, and < 3 lesions. CONCLUSION: Complete eradication of tumor burden with SBRT was associated with better survival in patients with oligometastatic RCC. The recommendation of SBRT to all lesions should be individualized.

Endoscopic versus stereotactic biopsies of intracranial lesions involving the ventricles.

Stereotactic biopsies of ventricular lesions may be less safe and less accurate than biopsies of superficial lesions. Accordingly, endoscopic biopsies have been increasingly used for these lesions. Except for pineal tumors, the literature lacks clear, reliable comparisons of these two methods. All 1581 adults undergoing brain tumor biopsy from 2007 to 2018 were retrospectively assessed. We selected 119 patients with intraventricular or paraventricular lesions considered suitable for both stereotactic and endoscopic biopsies. A total of 85 stereotactic and 38 endoscopic biopsies were performed. Extra procedures, including endoscopic third ventriculostomy and tumor cyst aspiration, were performed simultaneously in 5 stereotactic and 35 endoscopic cases. In 9 cases (5 stereotactic, 4 endoscopic), the biopsies were nondiagnostic (samples were nondiagnostic or the results differed from those obtained from the resected lesions). Three people died: 2 (1 stereotactic, 1 endoscopic) from delayed intraventricular bleeding and 1 (stereotactic) from brain edema. No permanent morbidity occurred. In 6 cases (all stereotactic), additional surgery was required for hydrocephalus within the first month postbiopsy. Rates of nondiagnostic biopsies, serious complications, and additional operations were not significantly different between groups. Mortality was higher after biopsy of lesions involving the ventricles, compared with intracranial lesions in any location (2.4% vs 0.3%, p = 0.016). Rates of nondiagnostic biopsies and complications were similar after endoscopic or stereotactic biopsies. Ventricular area biopsies were associated with higher mortality than biopsies in any brain area.

The effect of fractionated gamma knife radiosurgery on visual acuity in patients with optic nerve tumor.

BACKGROUND: Stereotactic radiosurgery (SRS) method has been considered the first-line treatment option to treat patients involved with pre-optic nerve tumors. However, studies have shown that using fractionated SRS, normal tissue sparing and tumor dose can be strongly increased simultaneously. Our main goal was to illustrate the effects of fractionated SRS approach in optic nerve tumor treatment and its adjacent sensitive structures. MATERIALS AND METHODS: 19 patients involved in optic nerve tumor with clinical symptoms of vision loss were treated with Gamma Knife radiosurgery in three sessions with 12 hours intervals between them. The prescribed dose was about 6.0 ± 1.2 Gy. Patient-related parameters including pre-treatment and after-treatment tumor size, visual acuity and visual field were evaluated using the Snell chart and MRI imaging. Patients were followed for about 14 months. RESULT: The overall result showed vision improvement for patients with low and moderate visual loss. However, there was no significant improvement in patients with severe visual loss. Relative improvement was observed in blind patients, although poorly. There was no evidence of growth, recurrence, or new tumor after treatment in patients. CONCLUSION: Fractionated gamma knife radiosurgery offers a safe and effective alternative for benign lesions adjacent to the optic nerve.

Role of Stereotactic Body Radiation Therapy for the Management of Oligometastatic Renal Cell Carcinoma.

PURPOSE: Kidney cancer has been increasing 1.7% annually. Renal cell carcinoma is the most common kidney cancer and it can metastasize. Our aim was to analyze patients treated with stereotactic body radiation therapy of renal cell carcinoma metastases. MATERIALS AND METHODS: A total of 58 patients (73 lesions) were treated from 2004 to 2016. Patients were candidates for analysis if a maximum of 3 metastases were diagnosed and the primary tumor was resected. Toxicity was classified according to Common Terminology Criteria for Adverse Events version 3. RESULTS: All patients had renal cell carcinoma, in particular the clear cell type in 82.7%. A total of 39 metastases (53.4%) were located in the lungs and 19 (26%) were in the lymph nodes. Less common were metastases to bone (9.5% of cases), the liver (4.1%) and the adrenal gland (6.8%). Median followup was 16.1 months (range 3.5 to 157.1). The local control rate at 12 and 18 months was 90.2% and 90.2%, respectively. The progression-free survival rate at 12 and 18 months was 46.2% (95% CI 32.2-59) and 35% (95% CI 21.4-48.9), respectively. On univariate and multivariable analyses metachronous and single metastases predicted better progression-free survival. Systemic therapy before stereotactic body radiation therapy predicted improved local control in clear cell cases. CONCLUSIONS: Stereotactic body radiation therapy can be considered a safe approach and it provides effective local control of oligometastatic renal cell carcinoma. However, future prospective studies are necessary to evaluate the impact on survival and quality of life.

Development of a Standardized Cranial Phantom for Training and Optimization of Functional Stereotactic Operations.

BACKGROUND: In recent years, simulations based on phantom models have become increasingly popular in the medical field. In the field of functional and stereotactic neurosurgery, a cranial phantom would be useful to train operative techniques, such as stereo-electroencephalography (SEEG), to establish new methods as well as to develop and modify radiological techniques. In this study, we describe the construction of a cranial phantom and show examples for it in stereotactic and functional neurosurgery and its applicability with different radiological modalities. METHODS: We prepared a plaster skull filled with agar. A complete operation for deep brain stimulation (DBS) was simulated using directional leads. Moreover, a complete SEEG operation including planning, implantation of the electrodes, and intraoperative and postoperative imaging was simulated. RESULTS: An optimally customized cranial phantom is filled with 10% agar. At 7°C, it can be stored for approximately 4 months. A DBS and an SEEG procedure could be realistically simulated. Lead artifacts can be studied in CT, X-ray, rotational fluoroscopy, and MRI. CONCLUSIONS: This cranial phantom is a simple and effective model to simulate functional and stereotactic neurosurgical operations. This might be useful for teaching and training of neurosurgeons, establishing operations in a new center and for optimization of radiological examinations.

Estimating Accurate Target Coordinates with Magnetic Resonance Images by Using Multiple Phase-Encoding Directions during Acquisition.

BACKGROUND: Stereotactic procedures are image guided, often using magnetic resonance (MR) images limited by image distortion, which may influence targets for stereotactic procedures. OBJECTIVES: The aim of this work was to assess methods of identifying target coordinates for stereotactic procedures with MR in multiple phase-encoding directions. METHODS: In 30 patients undergoing deep brain stimulation, we acquired 5 image sets: stereotactic brain computed tomography (CT), T2-weighted images (T2WI), and T1WI in both right-to-left (RL) and anterior-to-posterior (AP) phase-encoding directions. Using CT coordinates as a reference, we analyzed anterior commissure and posterior commissure coordinates to identify any distortion relating to phase-encoding direction. RESULTS: Compared with CT coordinates, RL-directed images had more positive x-axis values (0.51 mm in T1WI, 0.58 mm in T2WI). AP-directed images had more negative y-axis values (0.44 mm in T1WI, 0.59 mm in T2WI). We adopted 2 methods to predict CT coordinates with MR image sets: parallel translation and selective choice of axes according to phase-encoding direction. Both were equally effective at predicting CT coordinates using only MR; however, the latter may be easier to use in clinical settings. CONCLUSION: Acquiring MR in multiple phase-encoding directions and selecting axes according to the phase-encoding direction allows identification of more accurate coordinates for stereotactic procedures.

Suspicious breast calcifications undergoing stereotactic biopsy in women ages 70 and over: Breast cancer incidence by BI-RADS descriptors.

OBJECTIVES: To determine the malignancy rate overall and for specific BI-RADS descriptors in women ≥70 years who undergo stereotactic biopsy for calcifications. METHODS: We retrospectively reviewed 14,577 consecutive mammogram reports in 6839 women ≥70 years to collect 231 stereotactic biopsies of calcifications in 215 women. Cases with missing images or histopathology and calcifications associated with masses, distortion, or asymmetries were excluded. Three breast radiologists determined BI-RADS descriptors by majority. Histology, hormone receptor status, and lymph node status were correlated with BI-RADS descriptors. RESULTS: There were 131 (57 %) benign, 22 (10 %) atypia/lobular carcinomas in situ, 55 (24 %) ductal carcinomas in situ (DCIS), and 23 (10 %) invasive diagnoses. Twenty-seven (51 %) DCIS cases were high-grade. Five (22 %) invasive cases were high-grade, two (9 %) were triple-negative, and three (12 %) were node-positive. Malignancy was found in 49 % (50/103) of fine pleomorphic, 50 % (14/28) of fine linear, 25 % (10/40) of amorphous, 20 % (3/15) of round, 3 % (1/36) of coarse heterogeneous, and 0 % (0/9) of dystrophic calcifications. CONCLUSIONS: Among women ≥70 years that underwent stereotactic biopsy for calcifications only, we observed a high rate of malignancy. Additionally, coarse heterogeneous calcifications may warrant a probable benign designation. KEY POINTS: • Cancer rates of biopsied calcifications in women ≥70 years are high • Radiologists should not dismiss suspicious calcifications in older women • Coarse heterogeneous calcifications may warrant a probable benign designation.

Delayed Intraparenchymal and Intraventricular Hemorrhage Requiring Surgical Evacuation after MRI-Guided Laser Interstitial Thermal Therapy for Lesional Epilepsy.

BACKGROUND: Symptomatic intracranial hemorrhage is a rare complication of laser interstitial thermal therapy (LITT). OBJECTIVES: To present a unique case of delayed symptomatic intracranial hemorrhage occurring after a LITT procedure for epilepsy in a high-volume center (68 LITT procedures for pediatric epilepsy have been performed). METHODS: An 18-year-old male with epilepsy underwent LITT to an area of heterotopia near the right lateral ventricle. He did well initially and was discharged home on postoperative day 1 but returned on postoperative day 9 with headache and left hemiparesis. He was found to have intraparenchymal and intraventricular hemorrhage in the region of the LITT catheter tract. RESULTS: CT angiography on admission revealed a small vascular abnormality near the focus of hemorrhage suspicious for pseudoaneurysm, although conventional angiography was negative. The patient declined neurologically and underwent craniotomy and hemorrhage evacuation. He eventually convalesced and was discharged to inpatient rehabilitation with persistent left hemiparesis. He has been seizure free since the intervention but remains on antiepileptic drugs. CONCLUSIONS: Evidence from the literature suggests that the pathophysiology of symptomatic hemorrhage after LITT may be related to vascular injury and pseudoaneurysm formation from LITT catheter placement and/or thermal injury from the ablation itself.

[Computer-controlled high-precision radiation]. / Computergesteuerte Hochpräzisionsbestrahlung.

The irradiation of tumors in the brain is challenging due to the proximity of radiation sensitive critical structures and the tumors to be treated. In addition, irradiation above a certain level can cause irreversible damage to nerve tissue. The irradiation of benign and malignant brain tumors requires precise techniques to preserve critical structures while simultaneously administering a high radiation dose for maximum effectiveness. Therefore, stereotaxy, as a subspecialty of neurosurgery, has developed various irradiation techniques, e. g., intracerebral application of interstitial brachytherapy (SBT; stereotactic brachytherapy) and stereotactic radiosurgery (SRS). Due to the development of computer-controlled radiation techniques (e. g., Cyberknife) over the last 20 years, SRS has gained increasing importance.

Prevalent placement error of deep brain stimulation electrode in movement disorders (technical considerations).

BACKGROUND: Deep brain stimulation is an effective and safe technique. Displacement of the electrode relative to the optimal stimulation site can lead to insufficient effect and sometimes to the need of operative electrode re-position. OBJECTIVE: This study was aimed to analyse targeting accuracy of deep brain stimulation electrode implantation to subthalamic nucleus (STN) and globus pallidus internus (Gpi). It detected possible causes of inaccuracy and prevalent shift to certain direction. METHODS: Targeting accuracy was analysed in 47 patients with Parkinson´s disease (PD) and 11 patients with dystonia with bilateral implantation of deep brain stimulation electrodes between years 2009 and 2016. RESULTS: A shift of electrode to prevalent direction was observed on the left side to medial and posterior and on the right side to lateral direction. Greater shift was observed on the left side and in a higher angulation of trajectory laterally. Movement of the electrode, because of its traction in anchoring device, was identified as a possible factor for prevalent electrode shift. Calibration of stereotactic coordinates to correct prevalent shift was used. CONCLUSION: Targeting inaccuracy is the result of accumulation of errors in individual steps of electrode implantation. Direction of the shift can be random or it can be toward a prevalent direction. A correction of prevalent error can prevent a suboptimal electrode placement (Tab. 3, Fig. 11, Ref. 29).

Clinical Outcomes of Transplanted Modified Bone Marrow-Derived Mesenchymal Stem Cells in Stroke: A Phase 1/2a Study.

BACKGROUND AND PURPOSE: Preclinical data suggest that cell-based therapies have the potential to improve stroke outcomes. METHODS: Eighteen patients with stable, chronic stroke were enrolled in a 2-year, open-label, single-arm study to evaluate the safety and clinical outcomes of surgical transplantation of modified bone marrow-derived mesenchymal stem cells (SB623). RESULTS: All patients in the safety population (N=18) experienced at least 1 treatment-emergent adverse event. Six patients experienced 6 serious treatment-emergent adverse events; 2 were probably or definitely related to surgical procedure; none were related to cell treatment. All serious treatment-emergent adverse events resolved without sequelae. There were no dose-limiting toxicities or deaths. Sixteen patients completed 12 months of follow-up at the time of this analysis. Significant improvement from baseline (mean) was reported for: (1) European Stroke Scale: mean increase 6.88 (95% confidence interval, 3.5-10.3; P<0.001), (2) National Institutes of Health Stroke Scale: mean decrease 2.00 (95% confidence interval, -2.7 to -1.3; P<0.001), (3) Fugl-Meyer total score: mean increase 19.20 (95% confidence interval, 11.4-27.0; P<0.001), and (4) Fugl-Meyer motor function total score: mean increase 11.40 (95% confidence interval, 4.6-18.2; P<0.001). No changes were observed in modified Rankin Scale. The area of magnetic resonance T2 fluid-attenuated inversion recovery signal change in the ipsilateral cortex 1 week after implantation significantly correlated with clinical improvement at 12 months (P<0.001 for European Stroke Scale). CONCLUSIONS: In this interim report, SB623 cells were safe and associated with improvement in clinical outcome end points at 12 months. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov. Unique identifier: NCT01287936.

Navigated MRI-guided liver biopsies in a closed-bore scanner: experience in 52 patients.

OBJECTIVES: To evaluate clinical effectiveness and diagnostic efficiency of a navigation device for MR-guided biopsies of focal liver lesions in a closed-bore scanner. METHODS: In 52 patients, 55 biopsies were performed. An add-on MR navigation system with optical instrument tracking was used for image guidance and biopsy device insertion outside the bore. Fast control imaging allowed visualization of the true needle position at any time. The biopsy workflow and procedure duration were recorded. Histological analysis and clinical course/outcome were used to calculate sensitivity, specificity and diagnostic accuracy. RESULTS: Fifty-four of 55 liver biopsies were performed successfully with the system. No major and four minor complications occurred. Mean tumour size was 23 ± 14 mm and the skin-to-target length ranged from 22 to 177 mm. In 39 cases, access path was double oblique. Sensitivity, specificity and diagnostic accuracy were 88 %, 100 % and 92 %, respectively. The mean procedure time was 51 ± 12 min, whereas the puncture itself lasted 16 ± 6 min. On average, four control scans were taken. CONCLUSIONS: Using this navigation device, biopsies of poorly visible and difficult accessible liver lesions could be performed safely and reliably in a closed-bore MRI scanner. The system can be easily implemented in clinical routine workflow. KEY POINTS: • Targeted liver biopsies could be reliably performed in a closed-bore MRI. • The navigation system allows for image guidance outside of the scanner bore. • Assisted MRI-guided biopsies are helpful for focal lesions with a difficult access. • Successful integration of the method in clinical workflow was shown. • Subsequent system installation in an existing MRI environment is feasible.

[12 years of Computer-Aided Surgery around the Head : Developments in surgical planning and simulation from a Bern perspective]. / 12 Jahre Computer-Aided Surgery around the Head : Entwicklungen in der chirurgischen Planung und Simulation aus Berner Perspektive.

Over the past years, the multidisciplinary character of the international Computer-Aided Surgery around the Head (CAS-H) symposium has advanced many medical technologies, which were often adopted by industry. In Bern, the synergetic effects of the CAS-H symposium have enabled many experiences and developments in the area of computer-aided surgery. Planning and simulation methods in the areas of craniomaxillofacial surgery and otorhinolaryngology were developed and tested in clinical settings. In the future, further CAS-H symposia should follow, in order to promote the possibilities and applications of computer-assisted surgery around the head.

Leksell Frame-Based Stereotactic Biopsy for Infratentorial Tumor : Practical Tips and Considerations.

The Leksell frame-based transcerebellar approach was proposed with the arc support frame attached upside down to the Z coordinate. This study presented practical tips and considerations for obtaining adequate tissue samples for deep-seated cerebellar lesions or lower brainstem lesions specifically those accessible via the cerebellar peduncle. For practical insights, the Leksell coordinate frame G was fixed to prevent the anterior screw implantation within the temporalis muscle, to avoid interference with the magnetic resonance (MR)-adapter, and taking into account the magnetic field of MR in close proximity to the tentorium. After mounting of indicator box, the MR imaging evaluation should cover both the indicator box and the infratentorial region that deviated from it. The coordinates [X, Y, Za, Arc0, Ringa0] obtained from Leksell SurgiPlan® software (Elekta, Stockholm, Sweden) with arc 00 located on the patient's right side were converted to [X, Y, Zb=360-Za, Arc0, Ringb0=Ringa0-1800]. The operation was performed in the prone position under general anesthesia in four patients with deep cerebellar (n=3) and brainstem (n=1) tumors. The biopsy results showed two cases of diffuse large B-cell lymphoma, one metastatic braintumor and one glioblastoma. One patient required frame repositioning as a complication. Drawing upon the methodology outlined in existing literature, we anticipate that imparting supplementary expertise could render the stereotactic biopsy of infratentorial tumors more consistent and manageable for the practitioner, thereby facilitating adequate tissue samples and minimizing patient complications.

Cingulotomy for Intractable Pain: A Systematic Review of an Underutilized Procedure.

Pain management is a critical aspect of cancer treatment and palliative care, where pain can significantly impact quality of life. Chronic pain, which affects a significant number of people worldwide, remains a prevalent and challenging symptom for patients. While medications and psychosocial support systems play a role in pain management, surgical and radiological interventions, including cingulotomy, may be necessary for refractory cases. Cingulotomy, a neurosurgical procedure targeting the cingulate gyrus, aims to disrupt neural pathways associated with emotional processing and pain sensation, thereby reducing the affective component of pain. Although cingulotomy has shown promise in providing pain relief, particularly in patients refractory to traditional medical treatment, its use has declined in recent years due to advancements in non-destructive therapies and concerns about long-term efficacy and patient suitability. Modern stereotactic methods have enhanced the precision and safety of cingulotomy, reducing associated complications and mortality rates. Despite these advancements, questions remain regarding its long-term efficacy and suitability for patients with limited life expectancy, particularly those with cancer. A comprehensive systematic review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidelines, aimed at providing insights into the efficacy, potential benefits, and limitations of this neurosurgical procedure in managing intractable pain. An electronic search of PubMed, Embase, Scopus, and Web of Science was conducted with open database coverage dates. The review focused on outcomes such as pain intensity and quality of life. The inclusion criteria encompassed human studies of any age experiencing intractable cancer or non-cancer pain, with cingulotomy as the primary intervention. Various study designs were considered, including observational studies, clinical trials, and reviews focusing on pain and cingulotomy. Exclusion criteria included non-human studies, non-peer-reviewed articles, and studies unrelated to pain or cingulotomy. This review highlights the efficacy of stereotactic anterior cingulotomy in managing intractable pain, particularly when conventional treatments fail. Advanced MRI-guided techniques enhance precision, but challenges like cost and expertise persist. Studies included in this review showed significant pain relief with minimal adverse effects, although the optimal target remains debated. Neurocognitive risks exist, but outcomes are generally favorable. Expected adverse events include transient effects like urinary incontinence and confusion. Reoperation may be necessary for inadequate pain control, with a median pain relief duration of three months to a year. A double stereotactic cingulotomy appears to be safe and effective for refractory pain.

Clinical Applicability and Safety of Conventional Frame-Based Stereotactic Techniques for Stereoelectroencephalography.

Objective: Stereoelectroencephalography (SEEG) is increasingly being recognized as an important invasive modality for presurgical evaluation of epilepsy. This study focuses on the clinical and technical considerations of SEEG investigations when using conventional frame-based stereotaxy, drawing on institutional experience and a comprehensive review of relevant literature. Methods: This retrospective observational study encompassed the surgical implantation of 201 SEEG electrodes in 16 epilepsy patients using a frame-based stereotactic instrument at a single tertiary-level center. We provide detailed descriptions of the operative procedures and technical nuances for bilateral and multiple SEEG insertions, along with several illustrative cases. Additionally, we present a literature review on the technical aspects of the SEEG procedure, discussing its clinical implications and potential risks. Results: Frame-based SEEG electrode placements were successfully performed through sagittal arc application, with the majority (81.2%) of cases being bilateral and involving up to 18 electrodes in a single operation. The median skin-to-skin operation time was 162 minutes (interquartile range [IQR], 145-200), with a median of 13 minutes (IQR, 12-15) per electrode placement for time efficiency. There were two occurrences (1.0%) of electrode misplacement and one instance (0.5%) of a postoperative complication, which manifested as a delayed intraparenchymal hemorrhage. Following SEEG investigation, 11 patients proceeded with surgical intervention, resulting in favorable seizure outcomes for nine (81.8%) and complete remission for eight cases (72.7%). Conclusion: Conventional frame-based stereotactic techniques remain a reliable and effective option for bilateral and multiple SEEG electrode placements. While SEEG is a suitable approach for selected patients who are strong candidates for epilepsy surgery, it is important to remain vigilant concerning the potential risks of electrode misplacement and hemorrhagic complications.

Feasibility and efficacy of stereotactic ablative radiotherapy for Barcelona Clinic Liver Cancer-C stage hepatocellular carcinoma.

The purpose of this study was to assess the feasibility and efficacy of stereotactic ablative radiotherapy (SABR) for liver tumor in patients with Barcelona Clinic Liver Cancer (BCLC)-C stage hepatocellular carcinoma (HCC). We retrospectively reviewed the medical records of 35 patients between 2003 and 2011. Vascular invasion was diagnosed in 32 patients, extrahepatic metastases in 11 and both in 8. Thirty-two patients were categorized under Child-Pugh (CP) class A and 3 patients with CP class B. The median SABR dose was 45 Gy (range, 30-60 Gy) in 3-5 fractions. The median survival time was 14 months. The 1- and 3-yr overall survival (OS) rate was 52% and 21%, respectively. On univariate analysis, CP class A and biologically equivalent dose ≥ 80 Gy(10) were significant determinants of better OS. Severe toxicity above grade 3, requiring prompt therapeutic intervention, was observed in 5 patients. In conclusion, SABR for BCLC-C stage HCC showed 1-yr OS rate of 52% but treatment related toxicity was moderate. We suggest that patients with CP class A are the best candidate and at least SABR dose of 80 Gy(10) is required for BCLC-C stage.

Laparoscopic surgery for median arcuate ligament syndrome using real-time stereotactic navigation.

INTRODUCTION: In median arcuate ligament syndrome (MALS), a hyperplastic MAL causes compression and stenosis of the celiac artery (CA). The treatment involves releasing the external pressure on this artery by dissecting the ligament. However, it is difficult to identify the artery because of its deep anatomical location. Stereotactic navigation provides real-time information regarding the surgical instrument's location on computed tomography (CT) images. We utilized this system to overcome the difficulty of anatomical identification. MATERIALS AND SURGICAL TECHNIQUE: We present a case of aneurysm rupture caused by MALS, which was treated with laparoscopic MAL dissection with real-time stereotactic navigation. Surgery was performed in a hybrid operating room with three-dimensional C-arm CT (Artis Zeego, Siemens) and an installed Curve navigation system (BrainLab). Preoperative CT images were aligned with intraoperative C-arm CT-like images and the surgical instrument position was projected onto preoperative CT images. After the left gastric artery isolation, the fibrous tissue surrounding the left gastric artery was dissected toward the CA while confirming the location of the CA and aortic wall using the navigation system. The CA's diameter was dilated from 1.8 to 2.6 mm with intraoperative angiography. DISCUSSION: This is the first report of laparoscopic MAL dissection using real-time stereotactic navigation. Although navigation setting was time-intensive, this system helped us understand the anatomical structures and in safely and precisely dissecting the MAL.

A study on the proper catheter position in minimally invasive surgery using stereotactic aspiration plus urokinase for intracerebral hemorrhage.

OBJECTIVE: The surgical method for treating spontaneous intracranial hemorrhage (ICH) is not well established despite ICH's high prevalence and poor prognosis. Minimally invasive surgery has recently received attention; however, literature on this method is scarce. In particular, the appropriate location of the catheter in the hematoma has not been described. We examined whether the catheter position affects the hematoma reduction in a hematoma ＞50 cc. METHODS: We investigated the prognoses of 36 patients with ICH who underwent stereotactic aspiration and hematoma drainage using urokinase from January 2010 to December 2018 and the hematoma reduction rates according to the tube position. Two methods evaluated the position of the catheter. In the first method, the hematoma was an imaginary sphere. The center point was set as the operation target. We evaluated the catheter position by determining whether it was in the deep part or the outer part of the half point from that location to the hematoma margin. In the second method, we evaluated whether the catheter was located 1 cm inside the hematoma margin. RESULTS: In both the first and second evaluations, there were no differences in age, midline shift, intraventricular hemorrhage status, hematoma volume on admission, Glasgow Coma Scale score on admission, time to operation after symptom onset, and systolic blood pressure. The rates of decrease in bleeding and the prognoses were also not significantly different. CONCLUSIONS: If the catheter is in the hematoma, the rate of hematoma reduction at any position is similar.