Thalamic deep brain stimulation is a mainstay treatment for severe and drug-refractory essential tremor, but postoperative management may be complicated in some patients by a progressive cerebellar ...syndrome including gait ataxia, dysmetria, worsening of intention tremor and dysarthria. Typically, this syndrome manifests several months after an initially effective therapy and necessitates frequent adjustments in stimulation parameters. There is an ongoing debate as to whether progressive ataxia reflects a delayed therapeutic failure due to disease progression or an adverse effect related to repeated increases of stimulation intensity. In this study we used a multimodal approach comparing clinical stimulation responses, modelling of volume of tissue activated and metabolic brain maps in essential tremor patients with and without progressive ataxia to disentangle a disease-related from a stimulation-induced aetiology. Ten subjects with stable and effective bilateral thalamic stimulation were stratified according to the presence (five subjects) of severe chronic-progressive gait ataxia. We quantified stimulated brain areas and identified the stimulation-induced brain metabolic changes by multiple 18 F-fluorodeoxyglucose positron emission tomography performed with and without active neurostimulation. Three days after deactivating thalamic stimulation and following an initial rebound of symptom severity, gait ataxia had dramatically improved in all affected patients, while tremor had worsened to the presurgical severity, thus indicating a stimulation rather than disease-related phenomenon. Models of the volume of tissue activated revealed a more ventrocaudal stimulation in the (sub)thalamic area of patients with progressive gait ataxia. Metabolic maps of both patient groups differed by an increased glucose uptake in the cerebellar nodule of patients with gait ataxia. Our data suggest that chronic progressive gait ataxia in essential tremor is a reversible cerebellar syndrome caused by a maladaptive response to neurostimulation of the (sub)thalamic area. The metabolic signature of progressive gait ataxia is an activation of the cerebellar nodule, which may be caused by inadvertent current spread and antidromic stimulation of a cerebellar outflow pathway originating in the vermis. An anatomical candidate could be the ascending limb of the uncinate tract in the subthalamic area. Adjustments in programming and precise placement of the electrode may prevent this adverse effect and help fine-tuning deep brain stimulation to ameliorate tremor without negative cerebellar signs.
Resection is generally considered the gold standard for treatment of low-grade (WHO grades I and II) gliomas (LGGs) in childhood. However, approximately 30% to 50% of these tumors are inoperable ...because of their localization in highly eloquent brain areas. A few reports have suggested stereotactic brachytherapy (SBT) with implantation of iodine-125 ((125)I) seeds as a safe and effective local treatment alternative. This single-center study provides a summary of the long-term outcome after SBT in one of the largest reported patient series.
All pediatric patients treated with SBT ((125)I seeds; cumulative therapeutic dose 50-65 Gy within 9 months) by our group for LGG with follow-up of more than 6 months were included. Clinical and radiologic outcome, time to progression, and overall survival were evaluated. Prognostic factors (age, sex, Karnofsky performance score, tumor volume, and histology) for survival and disease progression were investigated.
In all, 147 of 160 pediatric patients treated with SBT (from 1982 through 2009) were analyzed in detail. Procedure-related mortality was zero, and the 30-day morbidity was transient and low (5.4%). Survival rates at 5 and 10 years were 93%, and 82%, respectively, with no significant difference between WHO grades I and II tumors (median follow-up, 67.1 ± 57.7 months). Twenty-one (14.8%) of 147 patients presented with tumor relapse. The remaining 126 patients revealed complete response in 24.6%, partial response in 31.0%, and stable disease in 29.6%. Neurologic status improved (57.8%) or remained stable (23.0%). None of the evaluated factors had significant impact on the study's end points except tumor volume more than 15 mL, which caused significantly higher rates of tumor recurrence (P < .05).
We demonstrate that SBT represents a safe, minimally invasive, and highly effective local treatment option for pediatric patients with inoperable LGG WHO grades I and II.
Foramen magnum meningiomas (FMMs) represent a considerable neurosurgical challenge given their location and potential morbidity. Stereotactic radiosurgery (SRS) is an established non-invasive ...treatment modality for various benign and malignant brain tumors. However, reports on single-session or multisession SRS for the management and treatment of FMMs are exceedingly rare. We report the largest FMM SRS series to date and describe our multicenter treatment experience utilizing robotic radiosurgery.
Patients who underwent SRS between 2005 and 2020 as a treatment for a FMM at six different centers were eligible for analysis.
Sixty-two patients met the inclusion criteria. The median follow-up was 28.9 months. The median prescription dose and isodose line were 14 Gy and 70%, respectively. Single-session SRS accounted for 81% of treatments. The remaining patients received three to five fractions, with doses ranging from 19.5 to 25 Gy. Ten (16%) patients were treated for a tumor recurrence after surgery, and thirteen (21%) underwent adjuvant treatment. The remaining 39 FMMs (63%) received SRS as their primary treatment. For patients with an upfront surgical resection, histopathological examination revealed 22 World Health Organization grade I tumors and one grade II FMM. The median tumor volume was 2.6 cubic centimeters. No local failures were observed throughout the available follow-up, including patients with a follow-up ≥ five years (16 patients), leading to an overall local control of 100%. Tumor volume significantly decreased after treatment, with a median volume reduction of 21% at the last available follow-up (
< 0.01). The one-, three-, and five-year progression-free survival were 100%, 96.6%, and 93.0%, respectively. Most patients showed stable (47%) or improved (21%) neurological deficits at the last follow-up. No high-grade adverse events were observed.
SRS is an effective and safe treatment modality for FMMs. Despite the paucity of available data and previous reports, SRS should be considered for selected patients, especially those with subtotal tumor resections, recurrences, and patients not suitable for surgery.
(1) Background: Infections in deep brain stimulation (DBS) hardware, while an undesired complication of DBS surgeries, can be effectively addressed. Minor infections are typically treated with wound ...revision and IV antibiotics. However, when visible hardware infection occurs, most centers opt for complete removal, leaving the patient in a preoperative state and necessitating post-removal care. To avoid the need for such care, a novel technique was developed. (2) Methods: The electrodes are placed at the exact same spot and then led to the contralateral side. new extensions and a new generator contralateral to the infection as well. Subsequently, the infected system is removed. This case series includes six patients. (3) Results: The average duration of DBS system implantation before the second surgery was 272 days. Only one system had to be removed after 18 months due to reoccurring infection; the others remained unaffected. Laboratory alterations and pathogens were identified in only half of the patients. (4) Conclusions: The described surgical technique proves to be safe, well tolerated, and serves as a viable alternative to complete system removal. Importantly, it effectively prevents the need of post-removal care for patients.
Deep brain stimulation of the subthalamic nucleus (STN-DBS) is a highly effective surgical treatment in patients with advanced Parkinson's disease (PD). Because the STN has been shown to represent an ...important relay station not only in motor basal ganglia circuits, the modification of brain areas also involved in nonmotor functioning can be expected by this intervention. To determine the impact of STN-DBS upon the regional cerebral metabolic rate of glucose (rCMRGlc), we performed positron emission tomography (PET) with 18-fluorodeoxyglucose (FDG) in eight patients with advanced PD before surgery as well as in the DBS on- and off-conditions 4 months after electrode implantation and in ten age-matched healthy controls. Before surgery, PD patients showed widespread bilateral reductions of cortical rCMRGlc versus controls but a hypermetabolic state in the left rostral cerebellum. In the STN-DBS on-condition, clusters of significantly increased rCMRGlc were found in both lower thalami reaching down to the midbrain area and remote from the stimulation site in the right frontal cortex, temporal cortex, and parietal cortex, whereas rCMRGlc significantly decreased in the left rostral cerebellum. Therefore, STN-DBS was found to suppress cerebellar hypermetabolism and to partly restore physiologic glucose consumption in limbic and associative projection territories of the basal ganglia. These data suggest an activating effect of DBS upon its target structures and confirm a central role of the STN in motor as well as associative, limbic, and cerebellar basal ganglia circuits.
The rates of incomplete surgical resection for pituitary macroadenomas with cavernous sinus invasion are high. In growth hormone-producing adenomas, there is a considerable risk for persistent ...acromegaly. Thus, effective treatment options are needed to limit patient morbidity and mortality. This multicenter study assesses the efficacy and safety of robotic radiosurgery (RRS) for patients with cavernous sinus-invading adenomas with persistent acromegaly.
Patients who underwent RRS with CyberKnife for postoperative acromegaly were eligible.
Fifty patients were included. At a median follow-up of 57 months, the local control was 100%. The pretreatment insulin-like growth factor 1 (IGF-1) levels and indexes were 381 ng/mL and 1.49, respectively. The median dose and prescription isodose were 18 Gy and 70%, respectively. Six months after RRS, and at the last follow-up, the IGF-1 levels and indexes were 277 ng/mL and 1.14, as well as 196 ng/mL and 0.83, respectively (
= 0.0001 and
= 0.0002). The IGF-1 index was a predictor for biochemical remission (
= 0.04). Nine patients achieved biochemical remission and 24 patients showed biochemical disease control. Three patients developed a new hypopituitarism.
RRS is an effective treatment for this challenging patient population. IGF-1 levels are decreasing after treatment and most patients experience biochemical disease control or remission.
This study investigates differences between treatment plans generated by Ray Tracing (RT) and Monte Carlo (MC) calculation algorithms in homogeneous and heterogeneous body regions. Particularly, we ...focus on the head and on the thorax, respectively, for robotic stereotactic radiotherapy and radiosurgery with Cyberknife. Radiation plans for tumors located in the head and in the thorax region have been calculated and compared to each other in 47 cases and several tumor types.
Assuming MC as the algorithm of highest accuracy it is shown that based on selected dose parameters, RT slightly underestimates the dose in homogeneous regions and overestimates in heterogeneous regions. In addition, deviations occur due to tumor size rendering large differences for small tumors. We conclude that dose prescriptions for radiotherapy treatments should differentiate between RT and MC calculation algorithm. This is especially important for small tumors in heterogeneous body regions.
This paper summarizes outcomes of a single-center study of intracavitary brachytherapy (IBT) with stereotactically applied phosphorus-32 (
32
P) colloid for treatment of cystic craniopharyngiomas. We ...assessed its efficacy and safety, on the basis of clinical and radiological outcomes in one of the largest reported patient series. Between 1992 and 2011, 53 patients were treated with IBT, 14 without previous treatment and 39 who had previously been treated for recurrent cysts. Intervention was performed by applying 200 Gy to the internal cyst wall (median volume 6.1 ml). Median clinical and radiological follow-up were 60.2 and 53.0 months, respectively. Actuarial tumor cyst control was 86.0 ± 5.3 % at 12, 24, and 60 months. Actuarial out-of-field control (development of new cysts or progression of solid tumor parts) was 90.9 ± 4.3, 84.0 ± 5.6, and 54.5 ± 8.8 % after 12, 24, and 60 months, respectively. Corresponding actuarial overall progression-free survival was 79.4 ± 6.1, 72.4 ± 6.8, and 45.6 ± 8.7 % at 12, 24, and 60 months, respectively. Visual function improved for 12 patients (23.5 %), remained unchanged for 34 patients (66.7 %), and worsened for five patients (9.8 %), correlating with tumor progression in each case. Endocrinological deterioration occurred for ten patients (19.6 %); for nine patients this was a result of tumor progression or after tumor resection and for one it was attributed to irradiation. Within six months of IBT seven patients (13.7 %) experienced transient neurological deficits and two patients (3.9 %) deteriorated permanently (hemiparesis and third nerve palsy). Stereotactically applied
32
P is highly efficacious for control of cystic components of craniopharyngiomas and is associated with a low risk of permanent morbidity. The procedure does not, however affect the development of new cysts or the progression of solid tumor parts.
Deep brain stimulation (DBS) indications include movement disorders, psychiatric affections, or epilepsy in which patients risk social isolation heightened by abnormal motions or behavioral patterns. ...Further stigmatization after DBS surgery from head shaving, visible scarring, or disfigurement from bulky lead insertion points should be avoided.
We present a cosmetically optimized, adapted submammarian approach for DBS neurostimulator implantation that leaves the décolletage untouched.
Over 24 months, 61 patients suffering from Parkinson disease, dystonia, or tremor underwent DBS surgery. The modified, submammarian approach was compared with the conventional infraclavicular approach regarding clinical outcome, complications, and limitations over a 5-year follow-up.
Neurostimulators were implanted in a paraumbilical (n = 20) or infraclavicular position (n = 41; Parkinson disease, n = 27; dystonia, n = 9; tremor, n = 5), the latter using a standard (n = 16), modified juxta-axillary (n = 6), or submammarian approach (n = 19; 18 women, 1 man with significant gynecomastia). After 12 months, there was no significant difference in the infection rate and one event of rebleeding in each group. Overall, operation time was longer (+20 minutes) for the submammarian versus standard, infraclavicular approach, but acceptable. Neurostimulator replacement was, necessary within 5 years due to advanced battery discharge (n = 32). Battery replacement was easily achieved using the submammarian approach (n = 14), again with increased surgical time (+20 minutes), and iatrogenic damage to extensions was avoidable.
A submammarian approach might be an alternative for infraclavicular implantation of DBS neurostimulators, particularly in female patients in the context of cosmetically optimized surgery. Patients' self-perception and self-esteem may be strengthened, potentially enabling them to better cope with disease.
PDF
