Transnasal Endoscopic Approach for Excision of Intracranial Nasal Dermoid Sinus Cysts.

OBJECTIVE: Nasal dermoid sinus cysts (NDSCs) with intracranial extension in the form of dermal sinus tracts require careful and complete resection to prevent recurrence. Resection techniques necessitate adequate intracranial exposure, but morbidity associated with historical resection approaches has presented unique multidisciplinary challenges for surgeons treating cysts with intracranial extension. METHODS: The authors primarily employed a transnasal approach through a midline nasal incision, utilizing endoscopic or microscopic access between the lateral cartilages for resection of NDSCs with intracranial extension. A retrospective review was completed for patients treated for NDSCs at the authors' pediatric quaternary referral center from 2017 to 2023. Data collection included demographics, comorbidities, perioperative data, pre and postoperative imaging, surgical outcomes, and complications. RESULTS: Eighteen patients with NDSCs with possible or confirmed intracranial extension were surgically treated from 2017 to 2023. Fifteen were treated with resection performed through a midline transnasal approach with endoscopic assistance, achieving successful total resection while avoiding nasal osteotomy or frontal craniotomy. One patient had a slow cerebrospinal fluid leak from an operative durotomy, successfully treated with a lumbar drain. No other complications occurred. No patients required transfusion. Incision length and postoperative scar burden were less than approaches that used osteotomies or craniotomies and demonstrated excellent cosmetic results. No patients have had cyst recurrence or required reoperation. CONCLUSIONS: A transnasal approach through a midline incision with endoscopic assistance is an effective approach for resection of NDSC with intracranial extension, but utility may vary with cyst size and complexity. This approach leverages appropriate exposure for resection with decreased morbidity and decreased incision length through avoidance of osteotomies.

Keloid Intralesional Excision Reduces Recurrence: A Meta-analytic Study of the Available Literature on 608 Keloids.

Background: The objective of this meta-analysis was to examine the effectiveness of keloid intralesional excision (KILE) in preventing recurrence. Treatment of keloids using surgical excision alone leads to high rates of recurrence. To date, there are no widely accepted guidelines for keloid treatment, and a multitude of adjunctive therapies are used to reduce recurrence. Despite these efforts, recurrence remains high. In this study, we conducted a meta-analysis of the existing literature on KILE to determine its role in recurrence reduction. Methods: A literature review using PubMed, Scopus, and Web of Science databases was performed. Two authors independently evaluated studies for eligibility. Incidence of keloid recurrence was recorded, and a comprehensive meta-analysis was performed to assess the pooled keloid recurrence rate, as well as the effect of additional therapies. Results: Twenty-two studies evaluating intralesional excision of 608 keloids were included in the study. Average time to follow-up was 19.2 months (range 6-35 months). A meta-analysis of proportions was conducted, demonstrating a pooled recurrence rate of 13% (95% confidence interval, 9%-16%). There was no evidence that using therapies in addition to KILE had a significant effect on the overall pooled recurrence rate. Conclusions: A meta-analysis of 608 keloids shows that KILE is an effective technique in preventing keloid recurrence, with a pooled recurrence rate of 13% compared with previously reported rates of 45%-100% after complete excision. Although there are no standard guidelines for keloid treatment, our meta-analysis shows that KILE is promising in recurrence reduction.

Physiologic signaling and viability of the muscle cuff regenerative peripheral nerve interface (MC-RPNI) for intact peripheral nerves.

Background. Robotic exoskeleton devices have become a promising modality for restoration of extremity function in individuals with limb loss or functional weakness. However, there exists no consistent or reliable way to record efferent motor action potentials from intact peripheral nerves to control device movement. Peripheral nerve motor action potentials are similar in amplitude to that of background noise, producing an unfavorable signal-to-noise ratio (SNR) that makes these signals difficult to detect and interpret. To address this issue, we have developed the muscle cuff regenerative peripheral nerve interface (MC-RPNI), a construct consisting of a free skeletal muscle graft wrapped circumferentially around an intact peripheral nerve. Over time, the muscle graft regenerates, and the intact nerve undergoes collateral axonal sprouting to reinnervate the muscle. The MC-RPNI amplifies efferent motor action potentials by several magnitudes, thereby increasing the SNR, allowing for higher fidelity signaling and detection of motor intention. The goal of this study was to characterize the signaling capabilities and viability of the MC-RPNI over time.Methods. Thirty-seven rats were randomly assigned to one of five experimental groups (Groups A-E). For MC-RPNI animals, their contralateral extensor digitorum longus (EDL) muscle was harvested and trimmed to either 8 mm (Group A) or 13 mm (Group B) in length, wrapped circumferentially around the intact ipsilateral common peroneal (CP) nerve, secured, and allowed to heal for 3 months. Additionally, one 8 mm (Group C) and one 13 mm (Group D) length group had an epineurial window created in the CP nerve immediately preceding MC-RPNI creation. Group E consisted of sham surgery animals. At 3 months, electrophysiologic analyses were conducted to determine the signaling capabilities of the MC-RPNI. Additionally, electromyography and isometric force analyses were performed on the CP-innervated EDL to determine the effects of the MC-RPNI on end organ function. Following evaluation, the CP nerve, MC-RPNI, and ipsilateral EDL muscle were harvested for histomorphometric analysis.Results. Study endpoint analysis was performed at 3 months post-surgery. All rats displayed visible muscle contractions in both the MC-RPNI and EDL following proximal CP nerve stimulation. Compound muscle action potentials were recorded from the MC-RPNI following proximal CP nerve stimulation and ranged from 3.67 ± 0.58 mV to 6.04 ± 1.01 mV, providing efferent motor action potential amplification of 10-20 times that of a normal physiologic nerve action potential. Maximum tetanic isometric force (Fo) testing of the distally-innervated EDL muscle in MC-RPNI groups producedFo(2341 ± 114 mN-2832 ± 102 mN) similar to controls (2497 ± 122 mN), thus demonstrating that creation of MC-RPNIs did not adversely impact the function of the distally-innervated EDL muscle. Overall, comparison between all MC-RPNI sub-groups did not reveal any statistically significant differences in signaling capabilities or negative effects on distal-innervated muscle function as compared to the control group.Conclusions. MC-RPNIs have the capability to provide efferent motor action potential amplification from intact nerves without adversely impacting distal muscle function. Neither the size of the muscle graft nor the presence of an epineurial window in the nerve had any significant impact on the ability of the MC-RPNI to amplify efferent motor action potentials from intact nerves. These results support the potential for the MC-RPNI to serve as a biologic nerve interface to control advanced exoskeleton devices.