A biophysically constrained brain connectivity model based on stimulation-evoked potentials.

BACKGROUND: Single-pulse electrical stimulation (SPES) is an established technique used to map functional effective connectivity networks in treatment-refractory epilepsy patients undergoing intracranial-electroencephalography monitoring. While the connectivity path between stimulation and recording sites has been explored through the integration of structural connectivity, there are substantial gaps, such that new modeling approaches may advance our understanding of connectivity derived from SPES studies. NEW METHOD: Using intracranial electrophysiology data recorded from a single patient undergoing stereo-electroencephalography (sEEG) evaluation, we employ an automated detection method to identify early response components, C1, from pulse-evoked potentials (PEPs) induced by SPES. C1 components were utilized for a novel topology optimization method, modeling 3D electrical conductivity to infer neural pathways from stimulation sites. Additionally, PEP features were compared with tractography metrics, and model results were analyzed with respect to anatomical features. RESULTS: The proposed optimization model resolved conductivity paths with low error. Specific electrode contacts displaying high error correlated with anatomical complexities. The C1 component strongly correlated with additional PEP features and displayed stable, weak correlations with tractography measures. COMPARISON WITH EXISTING METHOD: Existing methods for estimating neural signal pathways are imaging-based and thus rely on anatomical inferences. CONCLUSIONS: These results demonstrate that informing topology optimization methods with human intracranial SPES data is a feasible method for generating 3D conductivity maps linking electrical pathways with functional neural ensembles. PEP-estimated effective connectivity is correlated with but distinguished from structural connectivity. Modeled conductivity resolves connectivity pathways in the absence of anatomical priors.

Stereo-EEG-guided network modulation for psychiatric disorders: Surgical considerations.

BACKGROUND: Deep brain stimulation (DBS) and other neuromodulatory techniques are being increasingly utilized to treat refractory neurologic and psychiatric disorders. OBJECTIVE: /Hypothesis: To better understand the circuit-level pathophysiology of treatment-resistant depression (TRD) and treat the network-level dysfunction inherent to this challenging disorder, we adopted an approach of inpatient intracranial monitoring borrowed from the epilepsy surgery field. METHODS: We implanted 3 patients with 4 DBS leads (bilateral pair in both the ventral capsule/ventral striatum and subcallosal cingulate) and 10 stereo-electroencephalography (sEEG) electrodes targeting depression-relevant network regions. For surgical planning, we used an interactive, holographic visualization platform to appreciate the 3D anatomy and connectivity. In the initial surgery, we placed the DBS leads and sEEG electrodes using robotic stereotaxy. Subjects were then admitted to an inpatient monitoring unit for depression-specific neurophysiological assessments. Following these investigations, subjects returned to the OR to remove the sEEG electrodes and internalize the DBS leads to implanted pulse generators. RESULTS: Intraoperative testing revealed positive valence responses in all 3 subjects that helped verify targeting. Given the importance of the network-based hypotheses we were testing, we required accurate adherence to the surgical plan (to engage DBS and sEEG targets) and stability of DBS lead rotational position (to ensure that stimulation field estimates of the directional leads used during inpatient monitoring were relevant chronically), both of which we confirmed (mean radial error 1.2±0.9 mm; mean rotation 3.6±2.6°). CONCLUSION: This novel hybrid sEEG-DBS approach allows detailed study of the neurophysiological substrates of complex neuropsychiatric disorders.

A biophysically constrained brain connectivity model based on stimulation-evoked potentials.

Background: Single-pulse electrical stimulation (SPES) is an established technique used to map functional effective connectivity networks in treatment-refractory epilepsy patients undergoing intracranial-electroencephalography monitoring. While the connectivity path between stimulation and recording sites has been explored through the integration of structural connectivity, there are substantial gaps, such that new modeling approaches may advance our understanding of connectivity derived from SPES studies. New Method: Using intracranial electrophysiology data recorded from a single patient undergoing sEEG evaluation, we employ an automated detection method to identify early response components, C1, from pulse-evoked potentials (PEPs) induced by SPES. C1 components were utilized for a novel topology optimization method, modeling 3D conductivity propagation from stimulation sites. Additionally, PEP features were compared with tractography metrics, and model results were analyzed with respect to anatomical features. Results: The proposed optimization model resolved conductivity paths with low error. Specific electrode contacts displaying high error correlated with anatomical complexities. The C1 component strongly correlates with additional PEP features and displayed stable, weak correlations with tractography measures. Comparison with existing methods: Existing methods for estimating conductivity propagation are imaging-based and thus rely on anatomical inferences. Conclusions: These results demonstrate that informing topology optimization methods with human intracranial SPES data is a feasible method for generating 3D conductivity maps linking electrical pathways with functional neural ensembles. PEP-estimated effective connectivity is correlated with but distinguished from structural connectivity. Modeled conductivity resolves connectivity pathways in the absence of anatomical priors.

Brain mechanisms underlying the emotion processing bias in treatment-resistant depression.

Depression is associated with a cognitive bias towards negative information and away from positive information. This biased emotion processing may underlie core depression symptoms, including persistent feelings of sadness or low mood and a reduced capacity to experience pleasure. The neural mechanisms responsible for this biased emotion processing remain unknown. Here, we had a unique opportunity to record stereotactic electroencephalography (sEEG) signals in the amygdala and prefrontal cortex (PFC) from 5 treatment-resistant depression (TRD) patients and 12 epilepsy patients (as control) while they participated in an affective bias task in which happy and sad faces were rated. First, compared with the control group, patients with TRD showed increased amygdala responses to sad faces in the early stage (around 300 ms) and decreased amygdala responses to happy faces in the late stage (around 600 ms) following the onset of faces. Further, during the late stage of happy face processing, alpha-band activity in PFC as well as alpha-phase locking between the amygdala and PFC were significantly greater in TRD patients compared to the controls. Second, after deep brain stimulation (DBS) delivered to bilateral subcallosal cingulate (SCC) and ventral capsule/ventral striatum (VC/VS), atypical amygdala and PFC processing of happy faces in TRD patients remitted toward the normative pattern. The increased amygdala activation during the early stage of sad face processing suggests an overactive bottom-up processing system in TRD. Meanwhile, the reduced amygdala response during the late stage of happy face processing could be attributed to inhibition by PFC through alpha-band oscillation, which can be released by DBS in SCC and VC/VS.

Intracranial stimulation and EEG feature analysis reveal affective salience network specialization.

Emotion is represented in limbic and prefrontal brain areas, herein termed the affective salience network (ASN). Within the ASN, there are substantial unknowns about how valence and emotional intensity are processed-specifically, which nodes are associated with affective bias (a phenomenon in which participants interpret emotions in a manner consistent with their own mood). A recently developed feature detection approach ('specparam') was used to select dominant spectral features from human intracranial electrophysiological data, revealing affective specialization within specific nodes of the ASN. Spectral analysis of dominant features at the channel level suggests that dorsal anterior cingulate (dACC), anterior insula and ventral-medial prefrontal cortex (vmPFC) are sensitive to valence and intensity, while the amygdala is primarily sensitive to intensity. Akaike information criterion model comparisons corroborated the spectral analysis findings, suggesting all four nodes are more sensitive to intensity compared to valence. The data also revealed that activity in dACC and vmPFC were predictive of the extent of affective bias in the ratings of facial expressions-a proxy measure of instantaneous mood. To examine causality of the dACC in affective experience, 130 Hz continuous stimulation was applied to dACC while patients viewed and rated emotional faces. Faces were rated significantly happier during stimulation, even after accounting for differences in baseline ratings. Together the data suggest a causal role for dACC during the processing of external affective stimuli.

Contralateral C7 nerve transfer for severe pediatric brachial plexus injuries: donor site morbidity.

BACKGROUND: Pediatric brachial plexus injuries (BPI) can have a devastating impact on upper extremity function. With localized lesions, nerve grafting and transfers are well-described. However, reconstruction of pan-plexus (C5-T1) injuries (PPI) requires donor nerves outside of the brachial plexus. The cross C7 (CC7) nerve transfer extended with sural nerve grafts to the contralateral recipient nerve offers the advantage of supplying robust donor axons. Though controversial in the West, CC7 transfer is routine in many Asian centers. We present a case series of pediatric patients who underwent CC7 transfer for BPI. Our objective was to catalog donor site morbidity incurred by transferring the C7 nerve root. METHODS: This retrospective study was approved by the Institutional Review Board of our university. INCLUSION CRITERIA: patients under 18 years old that underwent CC7 nerve transfer for BPI at our health system between 2021 and 2022. A chart review was completed to collect demographic and outcomes data. RESULTS: Three patients underwent a complete CC7 transfer between 2021 and 2022 for BPI reconstruction. All patients underwent concomitant additional nerve transfers. Post-operative donor site sensory deficits were minimal and transient in all but one patient, who reported mild but persistent paresthesia of the donor side hand with movement of recipient side digits; however, no patients suffered donor site motor deficits (Table 1). CONCLUSIONS: We conclude that CC7 nerve transfer is a safe surgical option to provide additional donor motor axons for PPI in pediatric patients.

Decoding Depression Severity From Intracranial Neural Activity.

BACKGROUND: Disorders of mood and cognition are prevalent, disabling, and notoriously difficult to treat. Fueling this challenge in treatment is a significant gap in our understanding of their neurophysiological basis. METHODS: We recorded high-density neural activity from intracranial electrodes implanted in depression-relevant prefrontal cortical regions in 3 human subjects with severe depression. Neural recordings were labeled with depression severity scores across a wide dynamic range using an adaptive assessment that allowed sampling with a temporal frequency greater than that possible with typical rating scales. We modeled these data using regularized regression techniques with region selection to decode depression severity from the prefrontal recordings. RESULTS: Across prefrontal regions, we found that reduced depression severity is associated with decreased low-frequency neural activity and increased high-frequency activity. When constraining our model to decode using a single region, spectral changes in the anterior cingulate cortex best predicted depression severity in all 3 subjects. Relaxing this constraint revealed unique, individual-specific sets of spatiospectral features predictive of symptom severity, reflecting the heterogeneous nature of depression. CONCLUSIONS: The ability to decode depression severity from neural activity increases our fundamental understanding of how depression manifests in the human brain and provides a target neural signature for personalized neuromodulation therapies.

Supraclavicular Approach to the Brachial Plexus.

The brachial plexus consists of an intricate array of nerves originating from the C5-T1 ventral rami of the spinal cord. Their course is complex and can be substantially distorted after injury. Thus, dissection of the brachial plexus can be difficult. Here, we present a practical approach to the supraclavicular dissection of the brachial plexus, with emphasis on relevant anatomy and surgical landmarks. Methods: This anatomical review was prepared using intraoperative surgical imaging. In addition, illustrations are used to display the images in schematic form. We present a stepwise surgical approach to the supraclavicular dissection of the brachial plexus. We highlight the differences between pre- and postganglionic nerve root injuries, and also relevant anatomical variants of the brachial plexus. Results: Eleven steps are recommended to facilitate the supraclavicular approach to the brachial plexus. Conclusion: The supraclavicular dissection of the brachial plexus is reliable with consistent landmarks and can be carried out in a stepwise fashion.

Outcomes after Anterior Interosseous Nerve to Ulnar Motor Nerve Transfer.

Background Ulnar nerve lesions proximal to the elbow can result in loss of intrinsic muscle function of the hand. The anterior interosseous nerve (AIN) to deep motor branch of the ulnar nerve (DBUN) transfer has been demonstrated to provide intrinsic muscle reinnervation, thereby preventing clawing and improving pinch and grip strength. The purpose of this study was to evaluate the efficacy of the AIN to DBUN transfer in restoring intrinsic muscle function for patients with traumatic ulnar nerve lesions. Methods We performed a prospective, multi-institutional study of outcomes following AIN to DBUN transfer for high ulnar nerve injuries. Twelve patients were identified, nine of which were enrolled in the study. The mean time from injury to surgery was 15 weeks. Results At final follow-up (mean postoperative follow-up 18 months + 15.5), clawing was observed in all nine patients with metacarpophalangeal joint hyperextension of the ring finger averaging 8.9 degrees (+ 10.8) and small finger averaging 14.6 degrees (+ 12.5). Grip strength of the affected hand was 27% of the unaffected extremity. Pinch strength of the affected hand was 29% of the unaffected extremity. None of our patients experienced claw prevention after either end-to-end ( n = 4) or end-to-side ( n = 5) AIN to DBUN transfer. Conclusion We conclude that, in traumatic high ulnar nerve injuries, the AIN to DBUN transfer does not provide adequate intrinsic muscle reinnervation to prevent clawing and normalize grip and pinch strength.

Parent Perspectives for Type B Ulnar Polydactyly Management.

BACKGROUND: Type B ulnar polydactyly is one of the most commonly encountered congenital hand differences and can be treated with ligation or excision. The purpose of this study was to determine what factors families consider in selecting treatment for their child with type B ulnar polydactyly. METHODS: We reviewed treatment outcomes and administered a survey by telephone to parents of children with type B ulnar polydactyly treated at a pediatric hospital between 2015 and 2020. We assessed satisfaction, reasons for choosing treatment, and post-management complications. RESULTS: The families of 70 of the 156 consecutive treated patients were successfully contacted and agreed to participate (45% response rate). The mean follow-up was 27 months. Twenty-eight chose in-office suture ligation and 42 chose excision. Rapid treatment was prioritized by those who opted for in-office ligation (P = .044). The complication rate for suture ligation was significantly higher than excision (P < .0001), with the most common complication being a residual remnant (nubbin or neuroma stump) (64%). Respondents with residual remnant reported significantly less satisfaction with the appearance of their child's hand (P < .001) and with treatment outcomes (P = .028) compared to those without residual remnants. CONCLUSIONS: Factors considered by parents in choosing type of treatment for type B ulnar polydactyly vary and may be significantly influenced by the surgeon. Although the majority of parents remain extremely satisfied with their child's outcome regardless of management type, time to treatment plays a determinative role in parents opting for ligation rather than excision in the operating room.

The Association of Insurance Status and Complications After Carpal Tunnel Release.

BACKGROUND: Carpal tunnel release (CTR) is one of the most commonly performed procedures in hand surgery. Complications from surgery are a rare but significant patient dissatisfier. The purpose of this study was to determine whether insurance status is independently associated with complications after CTR. METHODS: We retrospectively identified all patients undergoing CTR between 2008 and 2018 using the Indiana Network for Patient Care, a state-wide health information exchange, and built a database that included patient demographics and comorbidities. Patients were followed for 90 days to determine whether a postoperative complication occurred. To minimize dropout, only patients with 1 year of encounters after surgery were included. RESULTS: Of the 26 151 patients who met inclusion criteria, 2662 (10.2%) had Medicare, 7027 (26.9%) had Medicaid, and 16 462 (62.9%) had commercial insurance. Compared with Medicare, Medicaid status (P < .001) and commercial insurance status (P < .001) were independently associated with postoperative CTR complications. The overall complication rate was 2.23%, with infection, wound breakdown, and complex regional pain syndrome being the most common complications. Younger age, alcohol use, diabetes mellitus, hypertension, and depression were also independently associated with complications. CONCLUSIONS: The incidence of complications after CTR is low. Insurance status, patient demographics, and medical comorbidities, however, should be evaluated preoperatively to appropriately risk stratify patients. Furthermore, surgeons can use these data to initiate preventive measures such as working to manage current comorbidities and lifestyle choices, and to optimize insurance coverage.

Prefrontal network engagement by deep brain stimulation in limbic hubs.

Prefrontal circuits in the human brain play an important role in cognitive and affective processing. Neuromodulation therapies delivered to certain key hubs within these circuits are being used with increasing frequency to treat a host of neuropsychiatric disorders. However, the detailed neurophysiological effects of stimulation to these hubs are largely unknown. Here, we performed intracranial recordings across prefrontal networks while delivering electrical stimulation to two well-established white matter hubs involved in cognitive regulation and depression: the subcallosal cingulate (SCC) and ventral capsule/ventral striatum (VC/VS). We demonstrate a shared frontotemporal circuit consisting of the ventromedial prefrontal cortex, amygdala, and lateral orbitofrontal cortex where gamma oscillations are differentially modulated by stimulation target. Additionally, we found participant-specific responses to stimulation in the dorsal anterior cingulate cortex and demonstrate the capacity for further tuning of neural activity using current-steered stimulation. Our findings indicate a potential neurophysiological mechanism for the dissociable therapeutic effects seen across the SCC and VC/VS targets for psychiatric neuromodulation and our results lay the groundwork for personalized, network-guided neurostimulation therapy.

Automated optimization of deep brain stimulation parameters for modulating neuroimaging-based targets.

Objective.Therapeutic efficacy of deep brain stimulation (DBS) in both established and emerging indications, is highly dependent on accurate lead placement and optimized clinical programming. The latter relies on clinicians' experience to search among available sets of stimulation parameters and can be limited by the time constraints of clinical practice. Recent innovations in device technology have expanded the number of possible electrode configurations and parameter sets available to clinicians, amplifying the challenge of time constraints. We hypothesize that patient specific neuroimaging data can effectively assist the clinical programming using automated algorithms.Approach.This paper introduces the DBS Illumina 3D algorithm as a tool which uses patient-specific imaging to find stimulation settings that optimizes activating a target area while minimizing the stimulation of areas outside the target that could result in unknown or undesired side effects. This approach utilizes preoperative neuroimaging data paired with the postoperative reconstruction of the lead trajectory to search the available stimulation space and identify optimized stimulation parameters. We describe the application of this algorithm in three patients with treatment-resistant depression who underwent bilateral implantation of DBS in subcallosal cingulate cortex and ventral capsule/ventral striatum using tractography optimized targeting with an imaging defined target previously described.Main results.Compared to the stimulation settings selected by the clinicians (informed by anatomy), stimulation settings produced by the algorithm that achieved similar or greater target coverage, produced a significantly smaller stimulation area that spilled outside the target (P= 0.002).Significance. The DBS Illumina 3D algorithm is seamlessly integrated with the clinician programmer software and effectively and rapidly assists clinicians with the analysis of image based anatomy, and provides a starting point to search the highly complex stimulation parameter space and arrive at the stimulation settings that optimize activating a target area.

Emergency Department Utilization After Administration of Peripheral Nerve Blocks for Upper Extremity Surgery.

BACKGROUND: The purpose of this study was to determine the impact of upper extremity peripheral nerve blocks on emergency department (ED) utilization after hand and upper extremity surgery. METHODS: We reviewed all outpatient upper extremity surgeries performed in a single Midwestern state between January 2009 and June 2019 using the Indiana Network for Patient Care. These encounters were used to develop a database of patient demographics, comorbidities, concurrent procedures, and postoperative ED visit utilization data. We performed univariate, bivariate, and multivariate logistic regression analyses. RESULTS: Among 108 451 outpatient surgical patients, 9079 (8.4%) received blocks. Within 1 week of surgery, a greater proportion of patients who received peripheral nerve blocks (1.4%) presented to the ED than patients who did not (0.9%) (P < .001). The greatest risk was in the first 2 postoperative days (relative risk, 1.78; P < .001). Pain was the principal reason for ED utilization in the block cohort (53.6%) compared with those who did not undergo a block (35.1%) (P < .001). When controlling for comorbidities and demographics, only peripheral nerve blocks (adjusted odds ratio [OR], 1.71; P = 0.007) and preprocedural opioid use (adjusted OR, 1.43; P = .020) conferred an independently increased risk of ED utilization within the first 2 postoperative days. CONCLUSIONS: Peripheral nerve blocks used for upper extremity surgery are associated with a higher risk of unplanned ED utilization, most likely related to rebound pain. Through proper patient education and pain management, we can minimize this unnecessary resource utilization.

Risk for Persistent Peripheral Neuropathy After Repair of Brachial Artery Injuries.

Background Brachial artery lacerations are limb-threatening injuries requiring emergent repair. Concomitant peripheral nerve symptoms are often only identified postoperatively. This study evaluated the prevalence of peripheral nerve deficits among this population as the indications for early nerve exploration have not been definitively established. Methods We reviewed all patients sustaining a brachial artery injury at one pediatric and two adult Level I Trauma Centers between January 1, 2007, and December 31, 2017. We recorded patient demographics, comorbidities, intoxication status, injury mechanism, concomitant injuries, type of repair, and intraoperative peripheral nerve exploration findings. Pre-and post-operative and long-term peripheral nerve function examination findings were analyzed. Differences between categorical variables were determined with Chi-square and Fisher's exact tests. Results Thirty-four patients sustained traumatic brachial artery lacerations requiring operative repair. Injury mechanisms included tidy (clean cut) laceration (n=11, 32%), gunshot wound (n=9, 26%), blunt trauma (n=8, 24%), and untidy laceration (n=6, 18%). Preoperatively, 15% had a normal peripheral nerve examination, 26% had localizable symptoms, 38% had non-localizable symptoms, and 21% were taken to the operating room without formal nerve assessment. Thirty-two percent underwent formal nerve exploration, and 81% underwent nerve repair. At an average follow-up of 2.5 years, 27% of patients underwent exploration, and 39% did not have localizable peripheral nerve deficits (p=0.705). Conclusions Brachial artery injuries are associated with a clinically significant risk for long-term peripheral nerve symptoms. Early nerve exploration in patients with peripheral nerve symptoms after a brachial artery injury may be warranted, although there is no statistically significant likelihood for improved peripheral neurological outcomes.

Imaging versus electrographic connectivity in human mood-related fronto-temporal networks.

BACKGROUND: The efficacy of psychiatric DBS is thought to be driven by the connectivity of stimulation targets with mood-relevant fronto-temporal networks, which is typically evaluated using diffusion-weighted tractography. OBJECTIVE: Leverage intracranial electrophysiology recordings to better predict the circuit-wide effects of neuromodulation to white matter targets. We hypothesize strong convergence between tractography-predicted structural connectivity and stimulation-induced electrophysiological responses. METHODS: Evoked potentials were elicited by single-pulse stimulation to two common DBS targets for treatment-resistant depression - the subcallosal cingulate (SCC) and ventral capsule/ventral striatum (VCVS) - in two patients undergoing DBS with stereo-electroencephalographic (sEEG) monitoring. Evoked potentials were compared with predicted structural connectivity between DBS leads and sEEG contacts using probabilistic, patient-specific diffusion-weighted tractography. RESULTS: Evoked potentials and tractography showed strong convergence in both patients in orbitofrontal, ventromedial prefrontal, and lateral prefrontal cortices for both SCC and VCVS stimulation targets. Low convergence was found in anterior cingulate (ACC), where tractography predicted structural connectivity from SCC targets but produced no evoked potentials during SCC stimulation. Further, tractography predicted no connectivity to ACC from VCVS targets, but VCVS stimulation produced robust evoked potentials. CONCLUSION: The two connectivity methods showed significant convergence, but important differences emerged with respect to the ability of tractography to predict electrophysiological connectivity between SCC and VCVS to regions of the mood-related network. This multimodal approach raises intriguing implications for the use of tractography in surgical targeting and provides new data to enhance our understanding of the network-wide effects of neuromodulation.

The Effects of Postoperative Physician Phone Calls for Hand and Wrist Fractures: A Prospective, Randomized Controlled Trial.

Background In this study, we sought to determine if postoperative physician phone calls following hand and wrist fracture surgery improve patient outcomes, satisfaction, and treatment adherence. Methodology We prospectively enrolled 24 consecutive adult patients who underwent outpatient surgery for isolated hand and wrist fractures at a single, metropolitan, safety-net hospital over one year to receive an additional physician phone call starting on postoperative day one. We measured preoperative and postoperative Brief Michigan Hand Questionnaire (bMHQ) composite score, overall satisfaction on a five-point Likert scale, compliance with treatment recommendations, presence of complications, discharge instructions reading level, and clarity of discharge and follow-up instructions. The surgical team was blinded to the treatment arm. Results The bMHQ score improved 26% after surgery; however, there was no difference in absolute score change between groups (12.2 vs. 6.5, p = 0.69). Most patients were satisfied throughout all stages of care, but postoperative satisfaction did not differ between groups (1.4 vs. 2.5, p = 0.21). There was a stronger correlation between patient hand function and satisfaction starting one month after surgery (R2 = 0.502, p = 0.002) than preoperatively (R2 = 0.252, p = 0.029). Immediately following surgery, most patients stated that discharge instructions were clear, and the average readability was below the average patient education level. Despite this, 13% removed their splint or Kirschner wires, 67% did not follow up within a week of recommendation, 62% did not complete postoperative treatment, and 33% had complications. Conclusions Postoperative phone calls by physicians did not improve compliance with recommendations, patient-rated outcome measures, or clinical outcomes among our hand and wrist fracture patient population.

Long-Term Outcomes After Treatment for Type B Ulnar Polydactyly.

BACKGROUND: Type B ulnar polydactyly is a common congenital hand difference and can be treated with either ligation or surgical excision. There is a paucity of literature, however, evaluating long-term patient reported outcomes of these treatments. The purpose of this study was to compare the long-term outcomes after ligation and excision for the management of type B ulnar polydactyly. METHODS: We created a database of patients who underwent treatment for type B ulnar polydactyly at a single pediatric health system from 2005 to 2014. We administered the Patient Reported Outcomes Measurement Information System (PROMIS) Pediatric Upper Extremity survey to patients through telephone and assessed for their satisfaction. RESULTS: We successfully collected outcomes from 69 of 173 eligible patients treated in infancy (40% response rate). The mean follow-up was 11.1±2.5 years, and the average age of the participant at the time of the survey was 11.7±2.6 years of age. Twenty-four patients were treated with in-office ligation and 45 underwent formal surgical excision. Ten patients who were initially treated with ligation required future treatment with surgery because of symptomatic neuroma stump or persistent polydactyly (42%). Patients who were treated with surgical excision rated significantly higher satisfaction with their treatment than those who underwent ligation (P=0.003). Patients in both cohorts rated similar satisfaction with the esthetic appearance of their hand (P=0.07). There was no significant difference in PROMIS-rated hand function between the ligation and surgical cohort (P=0.765) and treated adolescents PROMIS scores were not statistically different than age-matched controls without polydactyly. CONCLUSION: While ligation and surgical excision result in similar function and esthetics, patient satisfaction is higher after surgery. Furthermore, a significant number of patients fail ligation and ultimately undergo surgery for symptomatic neuroma or persistent polydactyly. Counseling parents of patients with type B ulnar polydactyly should include these considerations to assist them in selecting the best treatment for their child. LEVEL OF EVIDENCE: Level III.

Deep Brain Stimulation for Depression Informed by Intracranial Recordings.

The success of deep brain stimulation (DBS) for treating Parkinson's disease has led to its application to several other disorders, including treatment-resistant depression. Results with DBS for treatment-resistant depression have been heterogeneous, with inconsistencies largely driven by incomplete understanding of the brain networks regulating mood, especially on an individual basis. We report results from the first subject treated with DBS for treatment-resistant depression using an approach that incorporates intracranial recordings to personalize understanding of network behavior and its response to stimulation. These recordings enabled calculation of individually optimized DBS stimulation parameters using a novel inverse solution approach. In the ensuing double-blind, randomized phase incorporating these bespoke parameter sets, DBS led to remission of symptoms and dramatic improvement in quality of life. Results from this initial case demonstrate the feasibility of this personalized platform, which may be used to improve surgical neuromodulation for a vast array of neurologic and psychiatric disorders.

Utilization of Techniques for Upper Extremity Amputation Neuroma Treatment and Prevention.

This study aimed to understand the current utilization of surgical approaches for nerve ending management in upper extremity amputation to prevent and treat nerve-related pain. We administered a survey to 190 of 1270 surgeons contacted by email (15% response rate) and analyzed their demographics, practice patterns, and perceptions regarding techniques for nerve ending management in upper extremity amputees. Although many surgical techniques were employed, most surgeons (54%) performed traction neurectomy during amputation and, alternatively, bury nerve into muscle if a neuroma subsequently develops (52%). Surgeons in practice less than 10 years were more likely to perform targeted muscle reinnervation (TMR) and regenerative peripheral nerve interfaces (RPNI) than surgeons in practice greater than 10 years (p<0.001). TMR and RPNI were performed more frequently for proximal amputations than distal amputations, but there is no consensus regarding the optimal timing to utilize these techniques. Surgeons commonly cited improved prosthetic control, pain, and phantom limb symptoms as reasons for performing TMR and RPNI. Increased physician compensation as a consideration was more commonly cited among TMR non-adopter than adopters (31% vs 14%, p=0.008). There is no consensus regarding techniques for the prevention or treatment of nerve ending pain in upper extremity amputees. TMR and RPNI are being utilized with increasing frequency and both patient and surgeon factors affect implementation in clinical practice.