Stereotactic and Functional Neurosurgery最新文献

Introduction: Generalized dystonia is a motor disorder causing major limitations in daily living activities. Deep brain stimulation (DBS) is an established therapy for primary disorders, but its efficacy in secondary ones remains variable. Although quality of life (QoL) assessment is crucial in disabling conditions to understand the comprehensive impact of surgical treatment on daily life, the available questionnaires are not well adapted.

Methods: Herein, QoL after DBS was evaluated using a "homemade" scale. The DBS-QoL scale is a new questionnaire specifically designed for generalized dystonia patients.

Results: Twenty-one DYT1 patients and 40 cerebral palsy patients underwent globus pallidus internus DBS during the inclusion period. Clinical improvement was measured using the BFMDRS and compared to QoL evolution using the DBS-QoL. We identified a significant positive impact of DBS on motor and functional aspects for both groups, with superior gains in DYT1 patients. In this group, we found significant improvement in functional aspects, whereas in perinatal hypoxic patients, the opposite trend was reported, with better satisfaction in terms of wellbeing. Across both etiologies, patients expressed satisfaction with the surgical outcomes (83%).

Conclusion: QoL assessment, using a dedicated scale, was shown to complement BFMDRS, enhancing the detection of subtle symptom improvements in DBS-treated patients.

Introduction: Epilepsy is the fourth most common neurological disorder, affecting nearly 1% of the global population. Despite recent advancements in medical therapies, approximately one-third of patients remain refractory to treatment, necessitating consideration of surgical intervention. Historically, epilepsy surgery has been invasive and maximalist in nature, involving extensive brain resections with significant risk for morbidity. However, emerging approaches offer promising, less-invasive alternatives. One such technique is focused ultrasound (FUS), a rapidly evolving, incisionless, image-guided therapy that allows physicians to precisely target specific brain regions with ultrasonic energy to achieve a range of therapeutic effects.

Methods: Systematic methods were implemented to define the scope of preclinical and clinical applications of FUS to treat epilepsy. Inclusion criteria included preclinical experiment, case study, case series, cohort studies, and clinical trials involving therapeutic application of FUS for treatment of epilepsy of any etiology. The primary exclusion criterion was FUS for indications other than treatment of epilepsy.

Results: Forty-six published articles and 9 ongoing clinical trials were included for a total of 55 studies. For ablative therapies, 10 studies were identified, of which 2 were preclinical studies, 1 was a clinical proof-of-concept study, 3 were clinical case reports, 1 was a completed clinical pilot study, and 3 were ongoing Phase I-Phase II clinical trials. For neuromodulatory FUS, 30 studies were identified, of which 19 were preclinical studies, 1 was a clinical case report, 4 were clinical pilot studies, and 6 were ongoing Phase I-Phase II clinical trials. Lastly, with respect to FUS-mediated blood-brain barrier (BBB) opening studies, 15 were identified, all of which were preclinical studies.

Discussion: Currently, FUS has been clinically applied for targeted brain ablation (high intensity [HIFU]) and neuromodulation (low intensity [LIFU]), with recent basic science applications of sonogenetics and targeted drug delivery through the BBB (Precise Intracerebral Noninvasive Guided, or PING, Surgery) offering new opportunities for clinical translation. This review summarizes preclinical and clinical applications of FUS for epilepsy treatment, addresses challenges to implementation, and explores key areas for future research.

Introduction: Deep brain stimulation (DBS) is the gold-standard surgical treatment for essential tremor (ET) and tremor-predominant Parkinson's disease (TdPD). However, despite appropriate electrode placement and programming, patients may develop tremor recurrence due to disease progression. MRI-guided focused ultrasound (MRgFUS) thalamotomy is an alternative treatment to DBS and has been shown to yield durable tremor control in both ET and TdPD patients. However, MRgFUS thalamotomy in a patient with indwelling DBS electrodes has not been previously reported.

Case presentation: We present the case of a 77-year-old male with progressive TdPD who underwent bilateral globus pallidus internus (GPi) DBS with subsequent right unilateral ventral intermediate nucleus thalamotomy 23 months after DBS due to progressive tremor recurrence. At 6-month follow-up, his tremor has completely resolved.

Conclusion: This is the first report of MRgFUS thalamotomy for recurrent tremor with indwelling DBS electrodes. We found that MRgFUS thalamotomy as salvage therapy with implanted GPi DBS electrodes is both safe and effective. It represents a novel potential treatment paradigm for TdPD patients with persistent tremor despite otherwise effective GPi DBS.

Introduction: Stereoelectroencephalography-guided radio-frequency thermocoagulation (SEEG-RFTC) is a minimally invasive technique whereby radio-frequency thermocoagulation is performed using SEEG electrodes, following recording and stimulation. It helps to disconnect/disrupt or ablate the epileptogenic networks and provides both therapeutic and diagnostic abilities.

Methods: This study is a retrospective study (2016-2024). All underwent comprehensive epilepsy surgery workup (video EEG, MRI, ictal-SPECT, PET, and magnetoencephalography). SEEG was placed using robotic guidance. Recording of habitual seizure following stimulation (to produce seizures) was performed followed by SEEG-RFTC in the seizure onset zone (SOZ) at the bedside; electrodes were then explanted. If seizures recurred or were not controlled, this was followed by surgery over SOZ as guided by SEEG stimulation-induced functional mapping of eloquent cortices.

Results: Sixty-one patients underwent SEEG-RFTC, 41 males. Mean duration of seizures was as follows: 11 years; seizure frequency range 1-100/day. As per imaging, 5 had definite lesions, 12 dual substrates (either adjacent or distant), 5 doubtful lesions, 21 non-lesional on MRI, 9 localization on SPECT/PET/MEG but MRI doubtful, 4 eloquent cortex involvement, and 5 had bilateral substrates. SOZ was frontal in 18, temporal 35, insula 3, occipital 4, parietal 1. A total of 406 electrodes were implanted, a mean of 8.2 ± 3.5/patient. Mean follow-up was 42 ± 17.4 months. About 72% (44/61) responded transiently (mean transient seizure-free time 95 ± 19 days). Of these, 29 underwent surgery; 48% had good outcomes (classes 1 and 2). Overall, 22% (14/61) had good outcomes with SEEG-RFTC as stand-alone procedure (follow-up 28 + 6.2 months, range 6-32 months). The class 1 and 2 outcomes were 37% in MRI-negative and 53.8% in MRI-positive cases (p < 0.01). The transient seizure-free time in our study did not correlate with good outcomes, but presence or absence of a substrate did. Temporal substrates had better outcomes than extra-temporal (57% vs. 47%, classes 1 and 2, p < 0.01).

Conclusion: SEEG-RFTC is a minimally invasive and effective adjuvant to SEEG recording and stimulation, may be done bedside under awake conditions, and helps to disrupt/disconnect/ablate the abnormal networks. It may be therapeutic or can strengthen the hypothesis for a later surgical resection.

Background: The radiofrequency unilateral interruption of the spinothalamic tract (STT) at the level of the superior colliculi in the mesencephalon is one of the more ancient functional neurosurgery operations. Based on the literature review, our aim was to consider the potential role of this old intervention in the modern neurosurgical armamentarium against cancer pain taking into account the evolution of the operative technique and the emergence of alternative approaches.

Summary: We reviewed the literature in order to analyze the anatomical targeting of the STT, the technical strategies, the efficacy on pain, the morbi-mortality, the comparison of the safety efficacy ratio with other surgical techniques depending on the indications. Among 19 published series, only 4 are reporting only cancer pain patients. Two of these 4 series are reporting an anterior approach. At the level of the superior colliculi, the STT location is quite stable. With the anterior approach, a trajectory parallel to the quadrigeminal plate and a target at 7-8 mm from the midline, the rate of permanent oculomotor palsy is very low. In patients operated under local anesthesia with electrical stimulation of the target area, painful paresthesia due to injury of the medial lemniscus is very rare (min 0, max 6%). The rate of patient with analgesia of the painful area, pain relief, and stop of pain drugs in these conditions is around 80% (min 75%-max 86%) in cancer patients. Early pain recurrences appearing within a month are due to insufficient coagulation. When a morphine pump is not an option, this intervention can transform the comfort of the last days of patients with unilateral drug-resistant pain of the upper part of the body.

Key messages: Although very ancient, the stereotactic spinothalamic mesencephalic tractotomy by radiofrequency is turning out to offer a very good safety efficacy for lateralized cancer pain at the upper part of the body in drug-resistant patients with a modest life expectancy. We recommend the young generation of neurosurgeon involved in pain surgery to learn this remarkably effective intervention.

Background: Percutaneous cervical cordotomy (PCC) is a lesioning procedure that targets the anterolateral quadrant of the spinal cord to interrupt spinothalamic pain pathways. It provides rapid and durable analgesia for patients with unilateral, medically refractory cancer pain below the C5 dermatome. Although its utilization has declined with the expansion of pharmacological and neuromodulatory therapies, PCC remains a critical palliative intervention for patients in whom opioid therapy is ineffective or intolerable. Summary: This narrative review delineates the neuroanatomical underpinnings, technical evolution, and contemporary clinical outcomes associated with PCC. The procedure is typically performed at the C1-2 level under CT guidance, allowing precise lesion placement verified through impedance monitoring and intraoperative electrophysiological testing. Recent adaptations - including the use of deep sedation combined with neurophysiological mapping - have broadened the eligible patient population to include individuals unable to undergo awake procedures. Across modern clinical series, PCC provides immediate and substantial analgesia in over 90% of patients, frequently enabling significant reductions in opioid consumption and improvements in quality of life. Adverse events are uncommon and typically transient, though hemiparesis, respiratory dysfunction, and mirror pain remain recognized risks. Median post-procedural survival is generally short, reflecting delayed referral patterns and underscoring the need for earlier multidisciplinary consideration. Key Messages: PCC achieves rapid, durable, and substantial analgesia in appropriately selected patients with unilateral, treatment-refractory cancer pain. Advances in imaging and neurophysiological guidance have enhanced procedural accuracy and safety. Earlier integration into palliative care pathways may optimize patient outcomes and quality of life.

Introduction: Stereoencephalography (SEEG) has emerged as the most common technique for invasive monitoring as part of the preoperative workup for epilepsy surgery. The use of intracranial implants has the potential for vascular injury giving rise to pseudoaneurysm, followed by unpredictable, delayed hemorrhage. Confirmed cases of post-SEEG pseudoaneurysm, as well as suspected cases involving delayed hemorrhage after explanation, are very rare and have not allowed identification of the inciting cause.

Case presentation: A patient was evaluated over the course of two SEEG implantations before the decision to proceed with deep brain stimulation (DBS) of the anterior nucleus of the thalamus (ANT) to treat their drug-resistant epilepsy. Preoperative imaging for DBS revealed a pseudoaneurysm proximal to an SEEG craniostomy site. The lesion was treated with excision and vascular bypass, and the patient ultimately underwent DBS as planned. Retrospective analysis strongly implicated the SEEG implantation in pseudoaneurysmal formation, most likely via arterial collision resulting from entry site deviation from the planned stereotactic trajectory.

Conclusion: Pseudoaneurysm may be a more prevalent complication of SEEG than existing literature would suggest, as the delayed formation of these lesions can allow them to escape recognition on routine postoperative imaging. Though likely still uncommon, this may suggest the prudence of additional radiological surveillance. This complication is potentially devastating if unrecognized and untreated, but otherwise does not preclude further surgical therapies for epilepsy.

Introduction: Deep brain stimulation (DBS) and responsive neural stimulation (RNS) are effective for patients with pharmacoresistant epilepsy. Similar outcomes and increasingly convergent indications mean the choice of device may come down to other factors. Common to implanted therapeutic devices, wound-associated adverse outcomes are among the more common complications for these two procedures. However, there have been limited studies evaluating the differences in wound complication rates between DBS and RNS, despite the procedural differences for implantation for the two devices. Our objective was to analyze the differences in wound complication rates between patients who received DBS and RNS devices at the University of Colorado Hospital between 2016 and 2023.

Methods: All DBS and RNS surgeries performed from 2016 to 2023 for two surgeons at the University of Colorado Hospital were retrospectively reviewed. Wound complications included infection, hardware protrusion, or wound erosion requiring surgical washout, explant, or replacement. Risk factors evaluated included age, sex, diabetes, body mass index, and immunocompromised status. Incidence of complications and risk factors were evaluated and compared using a chi-squared and Mann-Whitney U test. The relationship between selected risk factors and the probability of wound complication was evaluated using a binomial logistic regression.

Results: A total of 297 patients underwent DBS (n = 234, n = 218 for movement disorders, n = 16 for epilepsy) and RNS (n = 63) implantation. The DBS group had higher median age at the time of surgery compared to the RNS group (65 vs. 37, p < 0.001), and no other significant differences in group characteristics were noted. Wound complication incidence was greater in the RNS group compared to DBS (12.7% vs. 4.3%, p < 0.001). No other risk factors were noted to contribute to wound complication rate.

Conclusion: Wound complication incidence was greater in RNS patients compared to DBS patients. Differences in age, sex, body mass index, and immunocompromised status were not associated with increased wound complication risk.

Introduction: In 2020, Elekta Instrument AB, Stockholm, released a new dose optimizer for Leksell GammaPlan, which includes the possibility of inverse planning. This study aimed to compare the new software with the previous manual version of treatment planning for stereotactic radiosurgery and evaluate its performance.

Materials and methods: Four types of diagnoses - vestibular schwannomas, pituitary adenomas, meningiomas, and single brain metastasis - along with 80 clinically approved challenging cases, were selected for testing the new software. Key parameters, including coverage, selectivity, target volume, and doses to critical structures, were collected and statistically analysed using a t test. These parameters were compared based on the Leksell Gamma Knife (LGK) Society standardization document for stereotactic radiosurgery, both for each diagnosis and for the entire dataset.

Results: The new software showed a clear advantage, particularly in sparing critical structures while maintaining or improving treatment plan conformity. Doses to critical structures such as the optic nerve, brainstem, cochlea, and pituitary gland decreased by an average of 13% (0.76 Gy), 7% (0.52 Gy), 7% (0.2 Gy), and 14% (1.04 Gy), respectively, reducing toxicity. Other plan parameters also showed significant improvements, except for the gradient index. Selectivity improved by 11% (0.03), the Shaw Conformity Index improved by 10% (0.1), and coverage improved by 0.01. Additionally, treatment time was reduced by 10% enhancing patient comfort.

Conclusion: Overall, LGK Lightning is faster and produces treatment plans with superior parameters compared to manual planning.

Introduction: Freezing of gait (FOG) is a clinical phenomenon with major life impairments and significant reduction in quality of life for affected patients. FOG is a feature of Parkinson's disease and a hallmark of primary progressive FOG, currently reclassified as Progressive Supranuclear Palsy-progressive gait freezing (PSP-PGF). The pathophysiology of FOG and particularly PGF, which is a rare degenerative disorder with a progressive natural history of gait decline, is poorly understood. Mechanistically, changes in oscillatory activity and synchronization in frontal cortical regions, the basal ganglia, and the midbrain locomotor region have been reported, indicating that dysrhythmic oscillations and coherence could play a causal role in the pathophysiology of FOG. Deep brain stimulation and spinal cord stimulation (SCS) have been tested as therapeutic neuromodulation avenues for FOG with mixed outcomes.

Methods: We analyzed gait and balance in 3 patients with PSP-PGF who received percutaneous thoracic SCS and utilized magnetoencephalography (MEG), electroencephalography, and electromyography to evaluate functional connectivity between the brain and spine.

Results: Gait and balance did not worsen over a 13-month period. This observation was accompanied by decreased beta-band spectral power in the whole brain and particularly in the basal ganglia. This was accompanied by increased functional connectivity in and between the sensorimotor cortices, basal ganglia, temporal cortex, and cerebellum, and a surge in corticomuscular coherence when SCS was paired with visual cues.

Conclusion: Our results suggest synergistic activity between brain and spinal circuits upon SCS for FOG in PGF, which may have implications for future brain-spine interfaces and closed-loop neuromodulation for patients with FOG.