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The subthalamic nucleus (STN) of the basal ganglia is key to the inhibitory control of movement. Consequently, it is a primary target for the neurosurgical treatment of movement disorders like Parkinson's disease, where modulating the STN via deep brain stimulation (DBS) can release excess inhibition of thalamocortical motor circuits. However, the STN is also anatomically connected to other thalamocortical circuits, including those underlying cognitive processes like attention. Notably, STN-DBS can also affect these processes. This suggests that the STN may also contribute to the inhibition of non-motor activity and that STN-DBS may cause changes to this inhibition. Here we tested this hypothesis in humans. We used a novel, wireless outpatient method to record intracranial local field potentials (LFP) from STN DBS implants during a visual attention task (Experiment 1, n = 12). These outpatient measurements allowed the simultaneous recording of high-density EEG, which we used to derive the steady state visual evoked potential (SSVEP), a well established neural index of visual attentional engagement. By relating STN activity to this neural marker of attention (instead of overt behaviour), we avoided possible confounds resulting from STN's motor role. We aimed to test whether the STN contributes to the momentary inhibition of the SSVEP caused by unexpected, distracting sounds. Furthermore, we causally tested this association in a second experiment, where we modulated STN via DBS across two sessions of the task, spaced at least 1 week apart (n = 21, no sample overlap with Experiment 1). The LFP recordings in Experiment 1 showed that reductions of the SSVEP after distracting sounds were preceded by sound-related γ-frequency (>60 Hz) activity in the STN. Trial-to-trial modelling further showed that this STN activity statistically mediated the sounds' suppressive effect on the SSVEP. In Experiment 2, modulating STN activity via DBS significantly reduced these sound-related SSVEP reductions. This provides causal evidence for the role of the STN in the surprise-related inhibition of attention. These findings suggest that the human STN contributes to the inhibition of attention, a non-motor process. This supports a domain-general view of the inhibitory role of the STN. Furthermore, these findings also suggest a potential mechanism underlying some of the known cognitive side effects of STN-DBS treatment, especially on attentional processes. Finally, our newly established outpatient LFP recording technique facilitates the testing of the role of subcortical nuclei in complex cognitive tasks, alongside recordings from the rest of the brain, and in much shorter time than peri-surgical recordings. [ABSTRACT FROM AUTHOR]

Objective: Endoscopic repair of skull base defects is required following resection of intracranial pathology via the endoscopic endonasal approach (EEA). Many closure techniques have been described, but choosing between techniques remains controversial. We report outcomes of 560 EEA procedures of skull base reconstruction performed on 508 patients over a 15‐year‐period. Halfway through this period, we adopted the use of a rigid, bioabsorbable extrasellar plate for reconstruction, enabling a comparison between this technique and those used previously. Methods: All patients undergoing EEA from 2005 to 2019 at our institution were retrospectively reviewed. Demographic information, surgical pathology, tumor dimensions and radiographic features, reconstructive technique, and patient‐related outcomes were collected and analyzed with univariate and multivariate statistical modeling. Results: Five‐hundred sixty procedures were performed on 508 patients. The series complication rate was 8.2%. Overall, cerebrospinal fluid (CSF) leak rate was 5.0% but varied significantly across closure techniques (p < 0.001). Critically, the CSF leak rate in the 272 cases prior to our 2013 adoption of the Resorb‐X Plate (RXP) was 8.5%, whereas leak rate in the subsequent 288 cases was 1.7%. RXP was protective against CSF leak (p = 0.001), whereas gross total resection (GTR) correlated with increased leak rate (p = 0.001). Patient BMI was significantly associated with risk of leak (p = 0.047). Other variables did not impact leak risk. Conclusion: Reconstructive technique, extent of resection, and patient BMI significantly contributed to CSF leak rate. GTR was associated with increased leak risk while the RXP was protective. The bioabsorbable RXP is an effective option for rigid skull base repair with comparatively few complications. Level of Evidence: 3 Laryngoscope, 133:1092–1098, 2023 [ABSTRACT FROM AUTHOR]

Objective  Anterior skull base meningiomas include olfactory groove, planum sphenoidale, and tuberculum sellae lesions. Traditionally, standard craniotomy approaches have been used to access meningiomas in these locations. More recently, minimally invasive techniques including supraorbital and endonasal endoscopic approaches have gained favor; however there are limited published series comparing the use of these two techniques for these meningiomas. Using our patent database, we identified patients who underwent these two approaches, and conducted a retrospective chart review to compare outcomes between these two techniques. Methods  A total of 32 patients who underwent minimally invasive approaches were identified: 20 supraorbital and 11 endoscopic endonasal. Radiographic images, presenting complaints and outcomes, were analyzed retrospectively. The safety of each approach was evaluated. Results  The mean extent of resection through a supraorbital approach was significantly greater than that of the endoscopic endonasal approach, 88.1 vs. 57.9%, respectively (p  = 0.016). Overall, preoperative visual acuity and anopsia deficits were more frequent in the endonasal group that persisted postoperatively (visual acuity: p  = 0.004; anopsia: p  = 0.011). No major complications including cerebrospinal fluid (CSF) leaks or wound-related complications were identified in the supraorbital craniotomy group, while the endonasal group had two CSF leaks requiring lumbar drain placement. Length of stay was shorter in the supraorbital group (3.4 vs. 6.1 days, p  < 0.001). Conclusion  Anterior skull base meningiomas can be successfully managed by both supraorbital and endoscopic endonasal approaches. Both approaches provide excellent direct access to tumor in carefully selected patients and are safe and efficient, but patient factors and symptoms should dictate the approach selected. [ABSTRACT FROM AUTHOR]

Dominant neuroanatomical models hold that humans regulate their movements via loop-like cortico-subcortical networks, which include the subthalamic nucleus (STN), motor thalamus, and sensorimotor cortex (SMC). Inhibitory commands across these networks are purportedly sent via transient, burst-like signals in the β frequency (15-29 Hz). However, since human depth-recording studies are typically limited to one recording site, direct evidence for this proposition is hitherto lacking. Here, we present simultaneous multi-site recordings from SMC and either STN or motor thalamus in humans performing the stop-signal task. In line with their purported function as inhibitory signals, subcortical β-bursts were increased on successful stop-trials. STN bursts in particular were followed within 50 ms by increased β-bursting over SMC. Moreover, between-site comparisons (including in a patient with simultaneous recordings from SMC, thalamus, and STN) confirmed that β-bursts in STN temporally precede thalamic β-bursts. This highly unique set of recordings provides empirical evidence for the role of β-bursts in conveying inhibitory commands along long-proposed cortico- subcortical networks underlying movement regulation in humans. [ABSTRACT FROM AUTHOR]

Introduction  Pituitary apoplexy commonly presents with visual and hormonal deficits. While traditionally regarded as an emergency, there have been increasing trends toward conservative management. Our institutional practice consists of early surgery; therefore, we reviewed our series evaluating vision outcomes, hormone function, and complications compared with the present literature. Methods  We retrospectively reviewed our institution's medical records to identify pituitary apoplexy patients who were treated via the endoscopic endonasal approach by a single neurosurgeon (senior author). We recorded basic demographics, radiographic and operative features, and preoperative and postoperative vision and hormone status. Univariate and multivariate statistical analyses were performed. Pooled data analysis of visual outcomes in the current literature using Bayesian inference was performed. Results  We identified 44 patients with histologically confirmed pituitary apoplexy treated by endoscopic transsphenoidal decompression; 77% were treated within 24 hours of presentation. Total 45% had cranial nerve (CN) palsy, 36% anopsia, and 20% had visual acuity deficits. Postoperatively, 100% of CN palsies improved, 81% of anopsias improved, and 66.7% of visual acuity deficits improved. Long-lasting panhypopituitarism (25%) and hypothyrodism (22%) were common. Cavernous sinus involvement predicted residual tumor (p  = 0.006). Pooled Bayesian inference showed 30% improvement in vision outcomes with surgical management compared with medical management with a number needed to treat of 3.3. Conclusion  Early surgery for pituitary apoplexy was associated with excellent visual outcomes and the need for long-term hormone replacement is common. Cavernous sinus involvement is an independent predictor of residual tumor. Pooled statistical analysis favors aggressive surgical management of apoplexy for improved visual outcomes. [ABSTRACT FROM AUTHOR]