Etiologies of iatrogenic occipital nerve injury: And outcomes following treatment with nerve decompression surgery.

INTRODUCTION: This study analyzed the etiologies and treatment of iatrogenic occipital nerve injuries. METHODS: Patients with occipital neuralgia (ON) who were screened for occipital nerve decompression surgery were prospectively enrolled. Patients with iatrogenic occipital nerve injuries who underwent nerve decompression surgery were identified. Data included surgical history, pain characteristics, and surgical technique. Outcomes included pain frequency (days/month), duration (h/day), intensity (0-10), migraine headache index (MHI), and patient-reported percent-resolution of pain. RESULTS: Among the 416 patients with ON, who were screened for occipital nerve decompression surgery, 12 (2.9%) cases of iatrogenic occipital nerve injury were identified and underwent surgical treatment. Preoperative headache frequency was 30 (±0.0) days/month, duration was 19.4 (±6.9) h, and intensity was 9.2 (±0.9). Neuroma excision was performed in 5 cases followed by targeted muscle reinnervation in 3, nerve cap in 1, and muscle burial in 1. In patients without neuromas, greater occipital nerve decompression and/or lesser occipital nerve neurectomy were performed. At the median follow-up of 12 months (IQR 12-12 months), mean pain frequency was 4.0 (±6.6) pain days/month (p < 0.0001), duration was 6.3 (±8.9) h (p < 0.01), and intensity was 4.4 (±2.8) (p < 0.001). Median patient-reported resolution of pain was 85% (56.3%-97.5%) and success rate was (≥50% MHI improvement) 91.7%. CONCLUSIONS: Iatrogenic occipital nerve injuries can be caused by various surgical interventions, including craniotomies, cervical spine interventions, and scalp tumor resections. The associated pain can be severe and chronic. Iatrogenic ON should be considered in the differential diagnosis of post-operative headaches and can be treated with nerve decompression surgery or neuroma excision with reconstruction of the free nerve end.

Surgical Management of Headache Disorders - A Systematic Review of the Literature.

PURPOSE OF REVIEW: This review article critically evaluates the latest advances in the surgical treatment of headache disorders. RECENT FINDINGS: Studies have demonstrated the effectiveness of innovative screening tools, such as doppler ultrasound, pain drawings, magnetic resonance neurography, and nerve blocks to help identify candidates for surgery. Machine learning has emerged as a powerful tool to predict surgical outcomes. In addition, advances in surgical techniques, including minimally invasive incisions, fat injections, and novel strategies to treat injured nerves (neuromas) have demonstrated promising results. Lastly, improved patient-reported outcome measures are evolving to provide a framework for comparison of conservative and invasive treatment outcomes. Despite these developments, challenges persist, particularly related to appropriate patient selection, insurance coverage, delays in diagnosis and surgical treatment, and the absence of standardized measures to assess and compare treatment impact. Collaboration between medical/procedural and surgical specialties is required to overcome these obstacles.

Micro-Coring: A Novel Approach to Perioral Rejuvenation.

BACKGROUND: A long philtrum and poor perioral skin quality are stigmata of the aging face. Micro-coring is a novel technology that allows for scarless skin removal. OBJECTIVES: This study aimed to determine if micro-coring can shorten the philtrum and improve perioral skin quality. METHODS: A retrospective cohort study was performed on subjects who underwent facelift with perioral micro-coring and age/BMI-matched control patients who underwent facelift alone. Preoperative and postoperative three-dimensional facial imaging was performed. Standard perioral distances and percent change were calculated. Perioral skin quality was evaluated by blinded raters using the Scientific Assessment Scale of Skin Quality (SASSQ) and Global Aesthetic Improvement Scale (GAIS). RESULTS: Thirteen subjects and thirteen controls were included with a mean follow-up of 8.9 months (range 3.0-21.5). Subjects had significantly shorter mean philtral length postoperatively as compared to preoperatively, with an average decrease of 6.18% (±2.25%) (p<0.05). Controls did not experience significant changes in philtrum length (p>0.05). Postoperative philtrum length was significantly shorter in subjects as compared to controls (p<0.05). There were no significant changes in other perioral measurements. Perioral skin elasticity and wrinkles significantly improved in subjects as compared to controls and subjects had significantly greater GAIS scores (p<0.05). CONCLUSIONS: Micro-coring can achieve perioral rejuvenation through measurable shortening of the philtrum and observable improvement in skin quality. Non-surgical techniques continue to find new ways to achieve aesthetic goals without significant recovery or scarring and offer value to patients and clinicians.

Reoperation Following Primary Greater Occipital Nerve Decompression Surgery: Incidence, Risk Factors and Outcomes.

BACKGROUND: Although nerve decompression surgery is an effective treatment for refractory occipital neuralgia (ON), a proportion of patients experience recurrence of pain and undergo reoperation. This study analyzes the incidence, risk factors, and outcomes of reoperation following primary greater occipital nerve (GON) decompression. METHODS: 215 patients who underwent 399 primary GON decompressions were prospectively enrolled. Data included patient demographics, past medical and surgical history, reoperation rates, intraoperative findings, surgical technique, and postoperative outcomes in terms of pain frequency (days/month), duration (hours/day), intensity (scale 0-10), and migraine headache index (MHI). Bivariate analyses, univariable and multivariable logistic regression analysis was performed. RESULTS: 27 (6.8%) GON decompressions required reoperation with neurectomy at a median follow-up time of 15.5 months (9.8-40.5). Cervical spine disorders on imaging that did not warrant surgical intervention (OR, 4.88; 95% 1.61-14.79; p<0.01) and radiofrequency ablation (RFA) (OR, 4.20; 95% CI, 1.45-15.2; p<0.05) were significantly associated with higher rates of reoperation. At 12 months postoperatively, patients who underwent reoperation achieved similar mean reductions in pain frequency, duration, intensity and MHI, as compared to patients who underwent only primary decompression (p>0.05). CONCLUSION: Patients with ON who have a history of cervical spine disorders or RFA should be counseled that primary decompression has a higher risk of reoperation, but outcomes are ultimately comparable.

Readability analysis and concept mapping of PROMs used for headache disorders.

OBJECTIVE: To assess the readability and the comprehensiveness of patient-reported outcome measures (PROMs) utilized in primary headache disorders literature. BACKGROUND: As the health-care landscape has evolved toward a patient-centric model, numerous PROMs have been developed to capture treatment outcomes in patients with headache disorders. For these PROMs to advance our understanding of headache disorders and their treatment impact, they must be easy to understand (i.e., reading grade level 6 or less) and comprehensively capture what matters to patients with headache. The aim of this study was to (a) assess the readability of PROMs utilized in headache disorders literature, and (b) assess the comprehensiveness of PROMs by mapping their content to a health-related quality of life framework. METHODS: In this scoping review, recently published systematic reviews were used to identify PROMs used in primary headache disorders literature. Readability analysis was performed at the level of individual items and full PROM using established readability metrics. The content of the PROMs was mapped against a health-related quality-of-life framework by two independent reviewers. RESULTS: In total, 22 PROMs (15 headache disorders related, 7 generic) were included. The median reading grade level varied between 7.1 (interquartile range [IQR] 6.3-7.8) and 12.7 (IQR 11.8-13.2). None of the PROMs were below the recommended reading grade level for patient-facing material (grade 6). Three PROMs, the Migraine-Treatment Assessment Questionnaire, the Eurolight, and the European Quality of Life 5 Dimensions 3 Level Version, were between reading grade levels 7 and 8; the remaining 19 PROMs were above reading grade level 8. In total, the PROMs included 425 items. Most items (n = 134, 32%) assessed physical function (e.g., work, activities of daily living). The remaining items assessed physical symptoms (n = 127, 30%; e.g., pain, nausea), treatment effects on symptoms (n = 65, 15%; e.g., accompanying symptoms relief, headache relief), treatment impact (n = 56, 13%; e.g., function, side effects), psychological well-being (n = 41, 10%; e.g., anger, frustration), social well-being (n = 29, 7%; e.g., missing out on social activities, relationships), psychological impact (n = 14, 3%; e.g., feeling [not] in control, feeling like a burden), and sexual well-being (n = 3, 1%; e.g., sexual activity, sexual interest). Some of the items pertained to treatment (n = 27, 6%), of which most were about treatment type and use (n = 12, 3%; e.g., medication, botulinum toxin), treatment access (n = 10, 2%; e.g., health-care utilization, cost of medication), and treatment experience (n = 9, 2%; e.g., treatment satisfaction, confidence in treatment). CONCLUSION: The PROMs used in studies of headache disorders may be challenging for some patients to understand, leading to inaccurate or missing data. Furthermore, no available PROM comprehensively measures the health-related quality-of-life impact of headache disorders or their treatment, resulting in a limited understanding of patient-reported outcomes. The development of an easy-to-understand, comprehensive, and validated headache disorders-specific PROM is warranted.

Peripheral neural interfaces: Skeletal muscles are hyper-reinnervated according to the axonal capacity of the surgically rewired nerves.

Advances in robotics have outpaced the capabilities of man-machine interfaces to decipher and transfer neural information to and from prosthetic devices. We emulated clinical scenarios where high- (facial) or low-neural capacity (ulnar) donor nerves were surgically rewired to the sternomastoid muscle, which is controlled by a very small number of motor axons. Using retrograde tracing and electrophysiological assessments, we observed a nearly 15-fold functional hyper-reinnervation of the muscle after high-capacity nerve transfer, demonstrating its capability of generating a multifold of neuromuscular junctions. Moreover, the surgically redirected axons influenced the muscle's physiological characteristics, by altering the expression of myosin heavy-chain types in alignment with the donor nerve. These findings highlight the remarkable capacity of skeletal muscles to act as biological amplifiers of neural information from the spinal cord for governing bionic prostheses, with the potential of expressing high-dimensional neural function for high-information transfer interfaces.

A Relative Value Unit-Based Model for Targeted Nipple-Areola Complex Neurotization in Gender-Affirming Mastectomy.

Background: For transmasculine individuals, double-incision mastectomy with free nipple grafts is the most common procedure for gender-affirming chest masculinization. However, patients report decreased sensation postoperatively. Direct coaptation of intercostal nerves to the nipple-areolar complex (NAC) is an experimental technique that may preserve postoperative sensation, yet whether reimbursements and billing codes incentivize hospital systems and surgeons to offer this procedure lacks clarity. Methods: A retrospective cross-sectional analysis of fiscal year 2023 Medicare physician fee schedule values was performed for neurotization procedures employing Current Procedural Terminology codes specified by prior studies for neurotization of the NAC. Additionally, operative times for gender-affirming mastectomy at a single center were examined to compare efficiency between procedures with and without neurotization included. Results: A total of 29 encounters were included in the study, with 11 (37.9%) receiving neurotization. The mean operating time was 100.3 minutes (95% CI, 89.2-111.5) without neurotization and 154.2 minutes (95% CI, 139.9-168.4) with neurotization. In 2023, the average work relative value units (wRVUs) for neurotization procedures was 13.38. Efficiency for gender-affirming mastectomy was 0.23 wRVUs per minute without neurotization and 0.24 wRVUs per minute with neurotization, yielding a difference of 0.01 wRVUs per minute. Conclusions: Neurotization of the NAC during double-incision mastectomy with free nipple grafts is an experimental technique that may improve patient sensation after surgery. Current reimbursement policy appropriately values the additional operative time associated with neurotization relative to gender-affirming mastectomy alone.

Prospective Sensory Outcomes for Targeted Nipple Areola Complex Reinnervation (TNR) in Gender-Affirming Double Incision Mastectomy with Free Nipple Grafting.

OBJECTIVE: This study analyses the anatomy and sensory outcomes of targeted nipple areola complex reinnervation (TNR) in gender-affirming double incision mastectomy with free nipple grafting (FNG). BACKGROUND: TNR is a novel technique to preserve and reconstruct intercostal nerves (ICN) to improve postoperative sensation. There is little evidence on relevant anatomy and outcomes. METHODS: 25 patients were prospectively enrolled. Data included demographics, surgical technique, and axon/fascicle counts. Quantitative sensory evaluation using monofilaments and qualitative patient reported questionnaires were completed preoperatively, and at one, three, six, nine and twelve months postoperatively. RESULTS: 50 mastectomies were performed. Per mastectomy, the median number of ICN found and used was 2 (1-5). Axon and fascicle counts were not significantly different between ICN branches ( P >0.05). BMI ≥30 kg/m 2 and mastectomy weight ≥800 g were associated with significantly worse preoperative sensation ( P <0.05). Compared to preoperative values, NAC sensation was worse at 1 month ( P <0.01), comparable at 3 months ( P >0.05), and significantly better at 12 months ( P <0.05) postoperatively. Chest sensation was comparable to the preoperative measurements at 1 and 3 months ( P >0.05), and significantly better at 12 months ( P <0.05) postoperatively. NAC sensation was significantly better when direct coaptation was performed compared to use of allograft only ( P <0.05), and with direct coaptation of ≥2 branches compared to direct coaptation of a single branch ( P <0.05). All patients reported return of nipple and chest sensation at one year postoperatively and 88% reported return of some degree of erogenous sensation. CONCLUSION: TNR allows for restoration of NAC and chest sensation within 3 months postoperatively. Use of multiple ICN branches and direct coaptation led to the best sensory outcomes.

A Decade of Nipple-Sparing Mastectomy: Lessons Learned in 3035 Immediate Implant-Based Breast Reconstructions.

BACKGROUND: Nipple-sparing mastectomy is commonly performed for breast cancer treatment or prevention. The authors present one of the largest breast reconstruction series in the literature. METHODS: A single-institution retrospective review was conducted from 2007 to 2019. RESULTS: The authors' query identified 3035 implant-based breast reconstructions after nipple-sparing mastectomy, including 2043 direct-to-implant and 992 tissue expander-to-implant reconstructions. The overall major complication rate was 9.15%, and the nipple necrosis rate was 1.20%. Therapeutic mastectomy was associated with higher overall complications and explantations compared with prophylactic mastectomy ( P < 0.01). In comparisons of unilateral and bilateral procedures, bilateral mastectomy had an increased risk for complications (OR, 1.46; 95% CI, 0.997 to 2.145; P = 0.05). Tissue-expander reconstructions had higher rates of nipple necrosis (1.9% versus 0.88%; P = 0.015), infection (4.2% versus 2.8%; P = 0.04), and explantation (5.1% versus 3.5%; P = 0.04) compared with direct-to-implant reconstruction. When assessing plane of reconstruction, the authors found similar rates of complications between subpectoral dual-plane and prepectoral reconstruction. There was no difference in complications between reconstruction with acellular dermal matrix or mesh compared with total or partial muscle coverage without acellular dermal matrix/mesh (OR, 0.749; 95% CI, 0.404 to 1.391; P = 0.361). Multivariable regression analysis revealed preoperative radiotherapy (OR, 2.465; 95% CI, 1.579 to 3.848; P < 0.001), smoking (OR, 2.53; 95% CI, 1.581 to 4.054; P < 0.001), and a periareolar incision (OR, 3.657; 95% CI, 2.276 to 5.875; P < 0.001) to be the strongest predictors of complications and nipple necrosis ( P < 0.05). CONCLUSIONS: Nipple-sparing mastectomy and immediate breast reconstruction has a low rate of complications. In this series, radiation therapy, smoking, and incision choice predicted overall complications and nipple necrosis, whereas direct-to-implant reconstruction and acellular dermal matrix or mesh did not increase risk. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.

Refractory occipital neuralgia treatment with nerve decompression surgery: a case series.

Background: The management of refractory occipital neuralgia (ON) can be challenging. Selection criteria for occipital nerve decompression surgery are not well defined in terms of clinical features and best preoperative medical management. Methods: In total, 15 patients diagnosed with ON by a board-certified, fellowship-trained headache specialist and referred to a plastic surgeon for nerve decompression surgery were prospectively enrolled. All subjects received trials of occipital nerve blocks (NB), at least three preventive medications, and onabotulinum toxin (BTX) prior to surgery before referral to a plastic surgeon. Treatment outcomes included headache frequency (headache days/month), intensity (0-10), duration (h), and response to medication/injectable therapies at 12 months postoperatively. Results: Preoperatively, median headache days/month was 30 (20-30), intensity 8 (8-10), and duration 24 h (12-24). Patients trialed 10 (±5.8) NB and 11.7 (±9) BTX cycles. Postoperatively, headache frequency was 5 (0-16) days/month (p < 0.01), intensity was 4 (0-6) (p < 0.01), and duration was 10 (0-24) h (p < 0.01). Median patient-reported percent resolution of ON headaches was 80% (70-85%). All patients reported improvement of comorbid headache disorders, most commonly migraine, and a reduction, discontinuation, or increased effectiveness of medications, NB and BTX. Conclusion: All patients who underwent treatment for refractory ON by a headache specialist and plastic surgeon benefited from nerve decompression surgery in various degrees. The collaborative selection criteria employed in this study may be replicable in clinical practice.

Treatment Delay in Patients Undergoing Headache Surgery (Nerve Decompression Surgery).

Background: Although headache surgery has been shown to be an effective treatment option for refractory headache disorders, it has not been included as part of the headache disorder management algorithm by non-surgical providers. This study aims to evaluate the delay in surgical management of patients with headache disorders. In addition, a cost comparison analysis between conservative and operative treatment of headache disorders was performed, and the surgical outcomes of headache surgery were reported. Methods: Among 1112 patients who were screened, 271 (56%) patients underwent headache surgery. Data regarding the onset of headache disorder and pre- and postoperative pain characteristics were prospectively collected. To perform a cost comparison analysis, direct and indirect costs associated with the conservative treatment of headache disorders were calculated. Results: The median duration between onset of headache disorder symptoms and headache surgery was 20 (8.2-32) years. The annual mean cost of conservative treatment of headache disorders was $49,463.78 ($30,933.87-$66,553.70) per patient. Over the 20-year time period before surgery, the mean cost was $989,275.65 ($618,677.31-$1,331,073.99). In comparison, the mean cost of headache surgery was $11,000. The median pain days per month decreased by 16 (0-25) (p<0.001), the median pain intensity reduced by 4 (2-7) (p<0.001), and the median pain duration decreased by 11 hours (0-22) (p<0.001). Conclusion: This study shows that patients experience symptoms of headache disorders for an average of 20 years prior to undergoing headache surgery. Surgical treatment not only significantly improves headache pain but also reduces healthcare costs and should be implemented in the management algorithm of headache disorders.

Functional outcomes between headache surgery and targeted botox injections: A prospective multicenter pilot study.

Introduction: Chronic migraine headaches (MH) are a principal cause of disability worldwide. This study evaluated and compared functional outcomes after peripheral trigger point deactivation surgery or botulinum neurotoxin A (BTA) treatment in patients with MH. Methods: A long-term, multicenter, and prospective study was performed. Patients with chronic migraine were recruited at the Ohio State University and Massachusetts General Hospital and included in each treatment group according to their preference (BTA or surgery). Assessment tools including the Migraine Headache Index (MHI), Migraine Disability Assessment Questionnaire (MIDAS) total, MIDAS A, MIDAS B, Migraine Work and Productivity Loss Questionnaire-question 7 (MWPLQ7), and Migraine-Specific Quality of Life Questionnaire (MSQ) version 2.1 were used to evaluate functional outcomes. Patients were evaluated prior to treatment and at 1, 2, and 2.5 years after treatment. Results: A total of 44 patients were included in the study (surgery=33, BTA=11). Patients treated surgically showed statistically significant improvement in headache intensity as measured on MIDAS B (p = 0.0464) and reduced disability as measured on MWPLQ7 (p = 0.0120) compared to those treated with BTA injection. No statistical difference between groups was found for the remaining functional outcomes. Mean scores significantly improved over time independently of treatment for MHI, MIDAS total, MIDAS A, MIDAS B, and MWPLQ 7 (p<0.05). However, no difference in mean scores over time was observed for MSQ. Conclusions: Headache surgery and targeted BTA injections are both effective means of addressing peripheral trigger sites causing headache pain. However, lower pain intensity and work-related disabilities were found in the surgical group.

Treatment Delay From Onset of Occipital Neuralgia Symptoms to Treatment with Nerve Decompression Surgery: A Prospective Cohort Study.

BACKGROUND: The aim of this study was to a) evaluate the time between onset of occipital neuralgia symptoms and nerve decompression surgery, b) perform a cost comparison analysis between surgical and non-surgical treatment of occipital neuralgia and c) report postoperative results of nerve decompression for occipital neuralgia. METHODS: 1,112 subjects who underwent screening for nerve decompression surgery were evaluated for occipital neuralgia. 367 (33%) patients met the inclusion criteria. Timing of occipital neuralgia symptom onset and pain characteristics were prospectively collected. Cost associated with the non-surgical treatment of occipital neuralgia was calculated for the period between onset of symptoms and surgery. RESULTS: 226 (73%) patients underwent occipital nerve decompression. The average time between onset of occipital neuralgia and surgery was 19 years (7.1-32). Postoperatively, the median number of pain days per month decreased by 17 (0-26, 57%) (p < 0.001), the median pain intensity decreased by 4 (2-8, 44%) (p < 0.001), and median pain duration in hours was reduced by 12 (2-23, 50%) (p < 0.001). The annual mean cost of non-surgical occipital neuralgia treatment was $28,728.82 ($16,419.42-$41,198.41) per patient. The mean cost during the 19-year timeframe prior to surgery was $545,847.75($311,968.90-$782,769.82). CONCLUSION: This study demonstrates that patients suffer from occipital neuralgia for an average of 19 years prior to undergoing surgery. Nerve decompression reduces symptom severity significantly and should be considered earlier in the treatment course of occipital neuralgia that is refractory to conservative treatment to prevent patient morbidity and decrease direct and indirect healthcare costs. IRB REGISTRATION NUMBER & NAME: Weill Cornell Medicine: 23-04025985, Prospective Cohort Study Investigating Long- Term Outcomes After Headache Surgery.The Massachusetts General Hospital: 2012P001527, Correlation of pre-operative pain self-efficacy and post-operative migraine-specific symptoms and disability.

The Use of Nerve Caps after Nerve Transection in Headache Surgery: Cadaver and Case Reports.

Background: Nerve transection with nerve reconstruction is part of the treatment algorithm for patients with refractory pain after greater occipital nerve (GON) and lesser occipital nerve (LON) decompression or during primary decompression when severe nerve injury or neuroma formation is present. Importantly, the residual nerve stump is often best addressed via contemporary nerve reconstruction techniques to avoid recurrent pain. As a primary aim of this study, nerve capping is explored as a potential viable alternative that can be utilized in certain headache cases to mitigate pain. Methods: The technical feasibility of nerve capping after GON/LON transection was evaluated in cadaver dissections and intraoperatively. Patient-reported outcomes in the 3- to 4-month period were compiled from clinic visits. At 1-year follow-up, subjective outcomes and Migraine Headache Index scores were tabulated. Results: Two patients underwent nerve capping as a treatment for headaches refractory to medical therapy and surgical decompressions with significant improvement to total resolution of pain without postoperative complications. These improvements on pain frequency, intensity, and duration remained stable at a 1-year time point (Migraine Headache Index score reductions of -180 to -205). Conclusions: Surgeons should be equipped to address the proximal nerve stump to prevent neuroma and neuropathic pain recurrence. Next to known contemporary nerve reconstruction techniques such as targeted muscle reinnervation/regenerative peripheral nerve interface and relocation nerve grafting, nerve capping is another viable method for surgeons to address the proximal nerve stump in settings of GON and LON pain. This option exhibits short operative time, requires only limited dissection, and yields significant clinical improvement in pain symptoms.

Relative Pain Reduction and Duration of Nerve Block Response Predict Outcomes in Headache Surgery: A Prospective Cohort Study.

BACKGROUND: Experts agree that nerve block (NB) response is an important tool in headache surgery screening. However, the predictive value of NBs remains to be proven in a prospective fashion. METHODS: Pre-NB and post-NB visual analogue pain scores (0 to 10) and duration of NB response were recorded prospectively. Surgical outcomes were recorded prospectively by calculating the Migraine Headache Index (MHI) preoperatively and postoperatively at 3 months, 12 months, and every year thereafter. RESULTS: The study population included 115 patients. The chance of achieving MHI percentage improvement of 80% or higher was significantly higher in subjects who reported relative pain reduction of greater than 60% following NB versus less than or equal to 60% [63 of 92 (68.5%) versus 10 of 23 (43.5%); P = 0.03]. Patients were more likely to improve their MHI 50% or more with relative pain reduction of greater than 40% versus 40% or less [82 of 104 (78.8%) versus five of 11 (45.5%); P = 0.01]. In subjects with NB response of greater than 15 days, 10 of 13 patients (77.0%) experienced MHI improvement of 80% or greater. Notably, all of these patients (100%) reported MHI improvement of 50% or greater, with mean MHI improvement of 88%. Subjects with a NB response of 24 hours or more achieved significantly better outcomes than patients with a shorter response (72.7% ± 37.0% versus 46.1% ± 39.7%; P = 0.02). However, of 14 patients reporting NB response of less than 24 hours, four patients had MHI improvement of 80% or greater, and seven, of 50% or greater. CONCLUSIONS: Relative pain reduction and duration of NB response are predictors of MHI improvement after headache surgery. NBs are a valuable tool to identify patients who will benefit from surgery. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, III.

The Superficial Inferior Epigastric Artery Axial Flap to Study Ischemic Preconditioning Effects in a Rat Model.

Fasciocutaneous flaps (FCF) have become the gold standard for complex defect reconstruction in plastic and reconstructive surgery. This muscle-sparing technique allows transferring vascularized tissues to cover any large defect. FCF can be used as pedicled flaps or as free flaps; however, in the literature, failure rates for pedicled FCF and free FCF are above 5%, leaving room for improvement for these techniques and further knowledge expansion in this area. Ischemic preconditioning (I.P.) has been widely studied, but the mechanisms and the optimization of the I.P. regimen are yet to be determined. This phenomenon is indeed poorly explored in plastic and reconstructive surgery. Here, a surgical model is presented to study the I.P. regimen in a rat axial fasciocutaneous flap model, describing how to safely and reliably assess the effects of I.P. on flap survival. This article describes the complete surgical procedure, including suggestions to improve the reliability of this model. The objective is to provide researchers with a reproducible and reliable model to test various ischemic preconditioning regimens and assess their effects on flap survivability.

Evidence-Based Patient Selection in Headache Surgery: Impact of Preoperative Radiofrequency Ablation on Surgical Outcomes.

BACKGROUND: Radiofrequency ablation (RFA) of the greater occipital nerve (GON) is a minimally invasive treatment option commonly used in patients with occipital neuralgia. Patients who undergo occipital surgery for headaches after failed RFA treatment present a unique opportunity to evaluate RFA-treated occipital nerves and determine the impact on headache surgery outcomes. METHODS: Of 115 patients who underwent headache surgery at the occipital site, 29 had a history of RFA treatment. Migraine Headache Index, Pain Self- Efficacy Questionnaire, and Pain Health Questionnaire-2 outcome scores were recorded preoperatively and at follow-up visits. Intraoperative macroscopic nerve damage and surgical outcomes were compared between RFA-treated and non-RFA-treated patients. RESULTS: RFA-treated patients had a higher rate of macroscopic nerve damage (45%) than non-RFA-treated patients (24%) ( P = 0.03), and they were significantly more likely to require a second operation at the site of primary decompression (27.6% versus 5.8%; P = 0.001) and GON transection (13.8% versus 3.5%; P = 0.04). Outcome scores at the last follow-up visit showed no statistically significant difference between RFA-treated and non-RFA-treated patients ( P = 0.96). CONCLUSIONS: RFA-treated patients can ultimately achieve outcomes that are not significantly different from non-RFA-treated patients in occipital headache surgery. However, a higher number of secondary operations at the site of primary decompression and nerve transection are required to treat refractory symptoms. RFA-treated patients should be counseled about an increased risk of same-site surgery and possible GON transection to achieve acceptable outcomes. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.

Artificial Intelligence-Enabled Evaluation of Pain Sketches to Predict Outcomes in Headache Surgery.

BACKGROUND: Recent evidence has shown that patient drawings of pain can predict poor outcomes in headache surgery. Given that interpretation of pain drawings requires some clinical experience, the authors developed a machine learning framework capable of automatically interpreting pain drawings to predict surgical outcomes. This platform will allow surgeons with less clinical experience, neurologists, primary care practitioners, and even patients to better understand candidacy for headache surgery. METHODS: A random forest machine learning algorithm was trained on 131 pain drawings provided prospectively by headache surgery patients before undergoing trigger-site deactivation surgery. Twenty-four features were used to describe the anatomical distribution of pain on each drawing for interpretation by the machine learning algorithm. Surgical outcome was measured by calculating percentage improvement in Migraine Headache Index at least 3 months after surgery. Artificial intelligence predictions were compared with clinician predictions of surgical outcome to determine artificial intelligence performance. RESULTS: Evaluation of the data test set demonstrated that the algorithm was consistently more accurate (94%) than trained clinical evaluators. Artificial intelligence weighted diffuse pain, facial pain, and pain at the vertex as strong predictors of poor surgical outcome. CONCLUSIONS: This study indicates that structured algorithmic analysis is able to correlate pain patterns drawn by patients to Migraine Headache Index percentage improvement with good accuracy (94%). Further studies on larger data sets and inclusion of other significant clinical screening variables are required to improve outcome predictions in headache surgery and apply this tool to clinical practice.