Identification Of Nerve Research Articles

Anatomical and histological investigation of the area anterior to the anorectum passing through the levator hiatus

Objective: To document the anatomical structure of the area anterior to the anorectum passing through the levator hiatus between the levator ani slings bilaterally. Methods: Three male hemipelvises were examined at the Laboratory of Clinical Applied Anatomy, Fujian Medical University. (1) The anatomical assessment was performed in three ways; namely, by abdominal followed by perineal dissection, by examining serial cross-sections, and by examining median sagittal sections. (2) The series was stained with hematoxylin and eosin to enable identification of nerves, vessels, and smooth and striated muscles. Results: (1) It was found that the rectourethralis muscle is closest to the deep transverse perineal muscle where the longitudinal muscle of the rectum extends into the posteroinferior area of the membranous urethra. The communicating branches of the neurovascular bundle (NVB) were identified at the posterior edge of the rectourethralis muscle on both sides. The rectum was found to be fixed to the membranous urethra through the rectourethral muscle, contributing to the anorectal angle of the anterior rectal wall. (2) Serial cross-sections from the anal to the oral side were examined. At the level of the external anal sphincter, the longitudinal muscle of the rectum was found to extend caudally and divide into two muscle bundles on the oral side of the external anal sphincter. One of these muscle bundles angled dorsally and caudally, forming the conjoined longitudinal muscle, which was found to insert into the intersphincteric space (between the internal and external anal sphincters). The other muscle bundle angled ventrally and caudally, filling the gap between the external anal sphincter and the bulbocavernosus muscle, forming the perineal body. At the level of the superficial transverse perineal muscle, this small muscle bundle headed laterally and intertwined with the longitudinal muscle in the region of the perineal body. At the level of the rectourethralis and deep transverse perineal muscle, the external urethral sphincter was found to occupy an almost completely circular space along the membranous part of the urethra. The dorsal part of the external urethral sphincter was found to be thin at the point of attachment of the rectourethralis muscle, the ventral part of the longitudinal muscle of the rectum. We identified a venous plexus from the NVB located close to the oral and ventral side of the deep transverse perineal muscle. Many vascular branches from the NVB were found to be penetrating the longitudinal muscle and the ventral part of rectourethralis muscle at the level of the apex of the prostate. The rectourethral muscle was wrapped ventrally around the membranous urethra and apex of the prostate. The boundary between the longitudinal muscle and prostate gradually became more distinct, being located at the anterior end of the transabdominal dissection plane. (3) Histological examination showed that the dorsal part of the external urethral sphincter (striated muscle) is thin adjacent to the striated muscle fibers from the deep transverse perineal muscle and the NVB dorsally and close by. The rectourethral muscle was found to fill the space created by the internal anal sphincter, deep transverse perineal muscle, and both levator ani muscles. Many tortuous vessels and tiny nerve fibers from the NVB were identified penetrating the muscle fibers of the deep transverse perineal and rectourethral muscles. The structure of the superficial transverse perineal muscle was typical of striated muscle. These findings were reconstructed three-dimensionally. Conclusions: In intersphincteric resection or abdominoperineal resection for very low rectal cancer, the anterior dissection plane behind Denonvilliers' fascia disappears at the level of the apex of the prostate. The prostate and both NVBs should be used as landmarks during transanal dissection of the non-surgical plane. The rectourethralis muscle should be divided near the rectum side unless tumor involvement is suspected. The superficial and deep transverse perineal muscles, as well as their supplied vessels and nerve fibers from the NVB. In addition, the cutting direction should be adjusted according to the anorectal angle to minimize urethral injury.

Benchtop simulation of the retrosigmoid approach: Validation of a surgical simulator and development of a task-specific outcome measure score

BackgroundNeurosurgical training is changing globally. Reduced working hours and training opportunities, increased patient safety expectations, and the impact of COVID-19 have reduced operative exposure. Benchtop simulators enable trainees to develop surgical skills in a controlled environment. We aim to validate a high-fidelity simulator model (RetrosigmoidBox, UpSurgeOn) for the retrosigmoid approach to the cerebellopontine angle (CPA). MethodsNovice and expert Neurosurgeons and Ear, Nose, and Throat surgeons performed a surgical task using the model – identification of the trigeminal nerve. Experts completed a post-task questionnaire examining face and content validity. Construct validity was assessed through scoring of operative videos employing Objective Structured Assessment of Technical Skills (OSATS) and a novel Task-Specific Outcome Measure score. ResultsFifteen novice and five expert participants were recruited. Forty percent of experts agreed or strongly agreed that the brain tissue looked real. Experts unanimously agreed that the RetrosigmoidBox was appropriate for teaching. Statistically significant differences were noted in task performance between novices and experts, demonstrating construct validity. Median total OSATS score was 14/25 (IQR 10–19) for novices and 22/25 (IQR 20–22) for experts (p < 0.05). Median Task-Specific Outcome Measure score was 10/20 (IQR 7–17) for novices compared to 19/20 (IQR 18.5–19.5) for experts (p < 0.05). ConclusionThe RetrosigmoidBox benchtop simulator has a high degree of content and construct validity and moderate face validity. The changing landscape of neurosurgical training mean that simulators are likely to become increasingly important in the delivery of high-quality education. We demonstrate the validity of a Task-Specific Outcome Measure score for performance assessment of a simulated approach to the CPA.

Masseteric Nerve Ultrasound Identification for Dynamic Facial Reanimation Purposes.

The masseteric nerve is one of the main options to neurotize free muscle flaps in irreversible long-term facial paralysis. Several preoperative skin-marking techniques for the masseteric nerve have been proposed to limit the surgical dissection area, shorten the surgical time, and enable a safer dissection. However, these have shown variability among them, and cannot visualize the nerve preoperatively. The authors designed an observational study to validate a high-frequency ultrasound (HFUS) nerve identification technique. A systematic HFUS examination was designed and performed to visualize the masseteric nerve in 64 hemifaces of healthy volunteers. One-third were randomly selected to undergo an additional HFUS-guided needle electrostimulation to validate the HFUS image. The masseteric nerve was identified by HFUS in 96.9% of hemifaces (95% CI, 0.89 to >0.99) and showed almost perfect agreement with direct needle stimulation as calculated with Cohen kappa coefficient (0.95; 95% CI, 0.85 to 1.00). The masseteric nerve was found within the masseter muscle, in between the deeper muscle bellies, at 18.3 mm (SD ±2.2) from the skin. Only in 12.9% of cases (95% CI, 0.06 to 0.24) did its course become adjacent to the mandible periosteum. Other important features, such as disposition in relation to the parotid gland, or if the nerve was covered directly by a thick intramuscular aponeurosis, could be well observed by HFUS. HFUS enables masseteric nerve identification and can provide the surgeon with specific information on anatomical relations for each examined individual before surgery.

Impact of Sternothyroid Muscle Division on Patient-Reported Voice Outcomes After Thyroid Surgery: A Prospective Study.

Division of the sternothyroid muscle during thyroidectomy is a widely accepted surgical technique to provide improved exposure of the thyroid gland, thus facilitating the ligation of superior pole vessels and identification of the laryngeal nerves. However, few have examined the impact on voice outcomes. We evaluate the impact of sternothyroid muscle division on patient-perceived voice outcomes after thyroidectomy. Prospective cohort study. Tertiary academic institution. A prospective cohort study was conducted comparing pre- and postoperative voice outcome data after thyroidectomy, measured using Voice Handicap Index-10. The cohort of 109 patients underwent lobectomy or total thyroidectomy by a single surgeon at 1 institution. The sternothyroid muscle was fully divided in all surgeries. The integrity of the recurrent laryngeal and external branches of the superior laryngeal nerve was assessed using intraoperative nerve monitoring and postoperative laryngoscopy. Pre- and postoperative Voice Handicap Index-10 scores were compared. No statistically significant difference was found between total pre- and postoperative Voice Handicap Index-10 scores (μpreop = 1.92, μpostop = 1.83, p = .87). There were no questions yielding statistically significant responses between pre- and postoperative groups. This was consistent regardless of whether the sternothyroid muscle was cut unilaterally or bilaterally. Men showed a statistically significant improvement in score after surgery. These findings support no difference in postoperative voice outcomes after the intraoperative division of the sternothyroid muscle. This supports the usage of this technique as a safe means to facilitate exposure during thyroid surgery and will serve as important information to guide intraoperative surgical decision-making.

Thyroidectomy With or Without Nerve Identification: A Personal Experience and Technique.

Careful and precise dissection of the gland, away from the typical trajectory of the recurrent and external laryngeal nerves, poses a minimal or similar risk of nerve injuries compared to directly visualizing and identifying the nerves. In a randomized controlled study involving 150 patients with various thyroid disorders who underwent different surgical procedures (total, near total, and hemi thyroidectomy), the patients were randomly assigned into two groups using a coin toss. The first group (G1) consisted of 75 patients who underwent thyroidectomy with nerve visual identification, while the second group (G2) comprised 75 patients without the requirement of nerve visualization. The aim was to determine the method with a lower risk of complications. The incidence of external laryngeal nerve palsy (ELNP) was found to be higher in G1 patients compared to G2 patients (5.3% vs2%), while no cases of permanent recurrent laryngeal nerve (RLN) palsy were observed in either group. The frequency of total nerve injury was higher in G1, with 14 patients (10.2%), compared to G2, with eight patients (5.3%). However, there was no significant association between nerve identification and the rate of nerve injury (P value = 0.452). Among the different surgical procedures, total thyroidectomy for toxic goiter was the most common operation associated with transient external laryngeal nerve (TELN) injury and permanent external laryngeal nerve (PELN) injury. By employing meticulous dissection techniques in proximity to the thyroid capsule, experienced surgeons can effectively reduce the risk of nerve injury, even in the absence of direct nerve visualization.

Non-recurrent laryngeal nerve in thyroid and parathyroid surgery

BACKGROUND: the main reason for postoperative vocal folds paresis is the variable anatomy of the recurrent laryngeal nerve. An example of such an “extreme form of embryonal development» is the non-recurrent laryngeal nerve. However, many surgeons consider this structure to be a rare anomaly with prevalence less than 0.5%. This opinion is associated with a six to seven-fold increase in the number of vocal folds paresis when a surgeon encounters with a non-recurrent laryngeal nerve. Meanwhile, in cadaveric studies a significantly higher prevalence of non-recurrent laryngeal nerve was demonstrated — 2.2%. The right aberrant subclavian artery was diagnosed during CT in 3.1% patients.AIM: the aim of the study is to determine the effectiveness of preoperative ultrasound in detecting the right aberrant subclavian artery and non-recurrent laryngeal nerve.MATERIALS AND METHODS: patients underwent thyroid and parathyroid surgery with identification of a right inferior laryngeal nerve. The preoperative neck ultrasound was performed on all patients with visualization of a brachiocephalic trunk (Y-sign) or a right aberrant subclavian artery (AL-sign). CT-angiography was performed in the postoperative period on patients who had a non-recurrent laryngeal nerve.RESULTS: the study included 1476 patients. The Y-sign was determined among 1338 (90.7%) patients. In these cases a typical anatomy of the recurrent laryngeal nerve was observed. In 138 (9.3%) cases, the Y-sign was not detected. In this subgroup of patients, in 20 (1.4%) cases, a non-recurrent laryngeal nerve and a right aberrant subclavian artery were noted. Thus, the sensitivity of the Y-sign in confirming the normal anatomy of the recurrent laryngeal nerve was 100%, specificity — 91.9%, positive prognostic value — 14.5%, negative prognostic value — 100%. On the contrary, AL-sign was notedall 20 (1.4%) patients with non-recurrent laryngeal nerve and right aberrant subclavian artery. False positive and false negative results were not observed. Three variants of the non-recurrent laryngeal nerve were identified: type I (superior type) — located behind the upper third of the thyroid lobe, has a direct descending way and forms an angle to the larynx of 30–50°; type III (inferior type) — has a direct ascending way (simulates the course of the recurrent laryngeal nerve) and forms an angle to trachea in 30–50°; type II (middle type) — all variants of the non-recurrent laryngeal nerve located between types I and III.CONCLUSION: the preoperative ultrasound detection of brachiocephalic trunk (Y-sign) confirms the presence of a recurrent laryngeal nerve (sensitivity 100%), and visualization of the right aberrant subclavian artery (AL-sign) determines a non-recurrent laryngeal nerve (sensitivity and specificity 100%).

Fluorescence Imaging to Identify and Preserve Fifth Intercostal Sensory Nerves during Bilateral Nipple-sparing Mastectomies.

The use of nipple-sparing mastectomies has increased steadily over the past 10-15 years. However, one major source of patient dissatisfaction with both skin- and nipple-sparing mastectomies is lost skin and/or nipple sensation postoperatively due to intraoperative, iatrogenic sensory nerve injury. We summarize the case of a 41-year-old woman with BRCA(+) breast cancer who underwent bilateral, risk-reducing nipple-sparing mastectomies, immediately followed by bilateral, direct-to-implant breast reconstruction, in whom a prototype fluorescent imaging camera was used to facilitate sensory nerve identification and preservation. Preoperatively, tactile and thermal quantitative sensory testing were performed using a 30-gauge needle to determine baseline sensory function over both breasts. Then, nipple-sparing mastectomies and direct-to-implant reconstruction were performed. Using a laterally-displaced submammary approach, the anterior intercostal artery perforator neurovascular pedicle was preserved. Then a prototype camera, which emits near-ultraviolet light, was used to detect nerve autofluorescence. Intraoperatively under near-ultraviolet light, both the fifth intercostal nerve and its sensory branches auto-fluoresced clearly, so that surgery was completed without apparent injury to the fifth intercostal nerve or any of its branches. Postoperatively, the patient reported full sensory function throughout both breasts and both nipple-areolar complexes, which was confirmed on both tactile and thermal sensory testing at 3-month follow-up. The patient experienced no complications and rated her overall satisfaction with surgery on both breasts as 10 out of 10. To our knowledge, this is the first time sensory nerve auto-fluorescence has been reported to reduce the likelihood of intraoperative, iatrogenic nerve injury and preserve sensory function.

재발성 갑상선암 수술 중 신경 모니터링 1예

The recurrent laryngeal nerve is a critical structure that must be carefully preserved during thyroid surgery. Any injury to this nerve can result in severe complications, including hoarseness, aspiration, and respiratory difficulty. Therefore, preserving the recurrent laryngeal nerve during surgery is crucial. In patients with a history of previous thyroid surgery, identification and preservation of the recurrent laryngeal nerve can be more challenging. We report a case of 43-year-old man diagnosed with recurrent papillary thyroid cancer who had previously total thyroidectomy with bilateral central neck dissection and right modified radical neck dissection due to papillary thyroid cancer. Re-do operation was successfully done without nerve injury using laryngeal nerve monitoring with electromyogram tube.

Label-free intraoperative nerve detection and visualization using ratiometric diffuse reflectance spectroscopy

Iatrogenic nerve injuries contribute significantly to postoperative morbidity across various surgical disciplines and occur in approximately 500,000 cases annually in the US alone. Currently, there are no clinically adopted means to intraoperatively visualize nerves beyond the surgeon’s visual assessment. Here, we report a label-free method for nerve detection using diffuse reflectance spectroscopy (DRS). Starting with an in vivo rat model, fiber- and imaging-based DRS independently identified similar wavelengths that provided optimal contrast for nerve identification with an accuracy of 92%. Optical property measurements of rat and human cadaver tissues verify that the source of contrast between nerve and surrounding tissues is largely due to higher scattering in nerve and differences in oxygenated hemoglobin content. Clinical feasibility was demonstrated in patients undergoing thyroidectomies using both probe-based and imaging-based approaches where the nerve were identified with 91% accuracy. Based on our preliminary results, DRS has the potential to both provide surgeons with a label-free, intraoperative means of nerve visualization and reduce the incidence of iatrogenic nerve injuries along with its detrimental complications.

P-086 NERVE IDENTIFICATION DURING OPEN MESH HERNIOPLASTY: A DESCRIPTIVE CROSS-SECTIONAL STUDY

Abstract Background It is recommended to identify nerves in the surgical field during open inguinal hernioplasty. This ensures proper dissection and reduces the incidence of post-operative inguinodynia. From limited surgical studies, it appears that identifying nerves may not be possible in all cases. Little is known about the factors that affect their identification. Materials and methods We conducted a cross-sectional study on thirty-six male patients with primary inguinal hernia. We looked for the nerves during Lichtenstein hernioplasty. We collected data on the identification &amp; preservation of nerves for calculating the nerve identification rates. We observed the course of the nerves and evaluated the effect of BMI, height, anaesthesia type, surgical experience, ASA, type of hernia and sac contents on nerve identification. Results Ilioinguinal nerve (IIN), Iliohypogastric Nerve (IHN), and Genital branch of genitofemoral nerve (GBN) were identified in 86.1%, 75%, and 50% of the groin dissections. It was easier to identify the IIN when the omentum was the content of the sac. The IHN was easily identified in patients with BMI ≤ 25 kg/m2. Conclusion Nerve identification can be challenging during surgery. The GBN and IHN are more prone to dissection-related injuries. Identification of IHN and IIN is difficult in overweight individuals and cases where hernia contains bowel.

OC-112 OUTCOMES OF EMERGENCY INGUINAL HERNIA SURGERIES PERFORMED BY TRAINEES AT A TERTIARY CARE HOSPITAL- AN AUDIT OF 43 CASES

Abstract Background An audit was performed to identify the outcomes after emergency inguinal hernia surgeries performed by trainees at our hospital from April to December 2022. Methods The prospectively maintained database of a single clinical unit of the Department of General Surgery of our institute was reviewed. Outcomes such as the types of surgery, SSI, length of hospital stay (LOH), re-exploration, long-term pain, recurrence, and other parameters were reviewed. Results 43 cases were reviewed. The mean age was 58.4 years. The mean symptom duration was 3.47 days. 16 (37.2%) patients had obstruction and 11 (25.5%) patients suffered strangulation. 25 (58.1%) patients required laparotomy apart from local exploration. Hernioplasty was done in 10 (23.2%) patients. Bassini was done in 10 (23.2%), Lytle's in 10 (23.2%), and Desarda repair in 23 (53.6%) patients. The mean operating time was 116.92 mins and the average blood loss was 93.7ml. 4 (9.3%) patients developed SSI, and 1 (2.32%) patient required mesh explantation. 1 (2.32%) required re-exploration and there was 1 mortality. The mean LOH was 4.33 days (2.32%). 20.93% of patients had long-term pain and none had a recurrence. Conclusion Patients getting operated on by trainees had a comparable mean operative time, more blood loss (53.7ml vs 22.0ml), more long-term pain (20.93% vs 1.2%), slightly more wound complications (9.3% vs 6.74%), comparable LOH, and comparable recurrence and mortality rates, when juxtaposed against reported literature. Surgical training should hence focus on meticulous dissection and identification of nerves to reduce blood loss and long-term pain.

Surgical aspects and early morbidity of patients undergoing open recurrent inguinal hernia repair.

This study aims to characterize the patterns of recurrence associated with specific types of primary inguinal hernia repair techniques used for and their respective correlations with early morbidity, in patients undergoing open repair for their first hernia recurrence. After ethics approval was obtained, a retrospective review of charts from patients who underwent open surgery for repair of a first recurrence after a previous inguinal hernia repair during 2013-2017 was completed. Statistical analyses were performed and p-values < .05 are reported as statistically significant. 1393 patients underwent 1453 surgeries for recurrent inguinal hernias at this institution. Operations for recurrence were longer (61.9 ± 21.1 vs. 49.3 ± 11.9; p < .001), required more frequent intra-operative surgical consultation (1% vs. 0.2%; p < .001) and had a higher incidence of surgical-site infections (0.8% vs. 0.4%; p = .03) than primary inguinal hernia repairs. When comparing the patterns of recurrence among different techniques of primary repairs, patients undergoing laparoscopic hernia repair presented with a higher incidence of indirect recurrences. Reoperations after a Shouldice repair and open mesh repair represented markers for higher surgical difficulty in the recurrent operation (longer operative time, higher identification of heavy scarring, less nerve identification, and higher frequency of intra-operative consultation), but not higher rates of complications when compared with other techniques. Open reoperations for inguinal hernia first recurrences are more complex, with noticeable differences according to the index operation, and associated with higher morbidity when compared with primary hernia repairs. This complexity varies according to the type of primary surgery, with a previous Shouldice repair and open hernia repair with mesh presenting higher surgical difficulties although this did not translate to higher incidence of early complications. This information may allow adequate allocation of surgeons with an expertise in recurrent hernias and choice of recurrent repair method (laparoscopic or open) based on the primary surgery.

Lower extremity peripheral nerve pathology: Utility of preoperative ultrasound-guided needle localization before operative intervention.

Historically, the use of ultrasound (US) in the management of peripheral nervous system (PNS) pathology has been limited to diagnostic confirmation or guidance for interventional injections. This technical case series will demonstrate the utility and versatility of preoperative US-guided needle localization for the excision of lower extremity neuromas and other pathology of the PNS. Five patients with symptomatic lower extremity PNS tumors were retrospectively reviewed. This case series corroborates the technical nuances of localizing lower extremity neuromas by US-guided needle and wire placement prior to operative excision. This was achieved by a multidisciplinary team that included plastic surgery, neurosurgery, and radiology. Five patients had US-guided needle localization of a lower extremity PNS target prior to operative intervention. Three patients had lower extremity neuromas of varying origins, including the lateral femoral cutaneous nerve (LFCN), saphenous nerve, and sural nerve. The remaining two patients had a sciatic nerve sheath Schwannoma and a femoral nerve glomus tumor. Under sonographic visualization, a needle was advanced to the target perimeter and withdrawn, leaving behind a percutaneous guidewire. This technique simplified the marking of the nerve course prior to dissection and led to efficient intraoperative identification of all five PNS tumors without any complications. Preoperative US-guided needle localization led to safe, accurate, and efficient perioperative and intraoperative identification of neuromas and other PNS tumors of the lower extremity prior to excision. By reducing the challenges of nerve identification in a scarred tissue bed, this multidisciplinary approach may decrease postoperative patient morbidity.

The effect of intraoperative nerve identification technique on distally-based dorsal fasciocutaneous flap for thumb and fingertip reconstruction

IntroductionThumb and fingertip resurfacing continues to be a challenge for hand surgeons, as the treatment varies widely. Being donor nerves in the flap for sensory restoration, the dorsal cutaneous nerves in hand have been widely described in the literature. However, their applications in providing anatomical information to sufficiently harvest the longitudinal axis of a robust flap are usually underestimated. This study reports reconstruction of thumb and fingertip defects with the distally based dorsal fasciocutaneous (DDF) flap and explores the effect of intraoperative nerve identification technique on clinical outcomes. HypothesisThe nerve identification technique can contribute considerably to the improvement of flap circulation, with less risk of poor venous return. Materials and methodsA retrospective study was conducted in 89 patients who had thumb or fingertip defects treated with the DDF flap from February 2014 to June 2020. Patients were divided into two groups based on whether intraoperative nerve identification technique was used. Flap survival was evaluated. The follow-up was conducted by using smartphone or by face-to-face visit. Time for complete wound healing, time to return to work, hand performance, the total active motion of the joints and static two-point discrimination of flaps were analyzed. ResultsThe 46 flaps (group A) that underwent intraoperative nerve identification technique had an 8.7% venous congestion rate versus a 27.9% venous congestion rate in the 43 flaps (group B) without using nerve identification technique (p=0.018). The mean follow-up was 11.08 (range 6–26) months. Time for complete wound healing and time to return to work were significantly shorter in group A (p=0.026 and p=0.012). Michigan Hand Outcomes Questionnaire (MHQ) scores were similar between groups. In the face-to-face follow-up, there was no significant difference in the total active motion of the injured fingers and static two-point discrimination between the two groups (p=0.657 and p=0.182). DiscussionThe use of nerve identification technique could decrease the odds of postoperative venous congestion in DDF flap for thumb and fingertip reconstruction, and result in improved outcomes in terms of time for complete wound healing and time to return to work. Level of evidenceIII; retrospective comparative study.

Dental MRI-only a future vision or standard of care? A literature review on current indications and applications of MRI in dentistry.

MRI is increasingly used as a diagnostic tool for visualising the dentoalveolar complex. A comprehensive review of the current indications and applications of MRI in the dental specialities of orthodontics (I), endodontics (II), prosthodontics (III), periodontics (IV), and oral surgery (V), pediatric dentistry (VI), operative dentistry is still missing and is therefore provided by the present work.The current literature on dental MRI shows that it is used for cephalometry in orthodontics and dentofacial orthopaedics, detection of dental pulp inflammation, characterisation of periapical and marginal periodontal pathologies of teeth, caries detection, and identification of the inferior alveolar nerve, impacted teeth and dentofacial anatomy for dental implant planning, respectively. Specific protocols regarding the miniature anatomy of the dentofacial complex, the presence of hard tissues, and foreign body restorations are used along with dedicated coils for the improved image quality of the facial skull.Dental MRI poses a clinically useful radiation-free imaging tool for visualising the dentoalveolar complex across dental specialities when respecting the indications and limitations.

Comparing Thyroidectomy Techniques, Surgical Loupe and Neuromonitoring Between ENT and Endocrine Surgeons-an Observational Study.

Thyroid surgery is performed by ENT head and neck (ENT-HNS), endocrine (ES) and general surgeons (GS). Each modality adopts different surgical techniques causing difference in outcome, operative time and postoperative complication. A retrospective chart review of thyroid surgeries performed by two ENT-HNS, three ES of a single tertiary center was conducted. We compared the use of neuromonitoring and surgical loupe and subsequent patient outcomes between surgeries performed by ENT-HNS versus ES, focusing on parathyroid gland identification, operative duration, vocal cord paralysis and length of hospital stay. A total of 167 patients underwent thyroid surgery. Surgical loupes were used in all the surgeries performed by ENT-HNS vs. 85% by the ES. Parathyroid glands were identified in all the surgeries performed by ENT-HNS versus 95% by ES. Neuromonitoring was used in all the surgeries performed by ENT-HNS, and none by the ES. Vocal cord paralysis developed in two patients of ES versus none in the ENT-HNS. Mean operative duration for total thyroidectomy in ENT-HN surgeries, 183.7min vs. 151min in the ES. The mean hospital stay of patients was 3.6 ± 1.6 days for ENT-HNS, and 5.45 ± 3 days for ES. Identification of parathyroid gland and recurrent laryngeal nerve by neuromonitoring and surgical loupes may increase operative time but decrease the rate of vocal cord paralysis and increases the chance of parathyroid gland identification.

Anatomical Variations of the External Jugular Vein: A Pictorial and Critical Review

(1) Background: The external jugular vein (EJV) descends on the sternocleidomastoid muscle to drain deep into the subclavian vein. Anatomical variations of the EJV are relevant for identification of the greater auricular nerve, flap design and preparation, or EJV cannulation. (2) Methods: Different publications were comprehensively reviewed. Dissections and three-dimensional volume renderings of peculiar cases were used to sample the review. (3) Results: Different anatomical possibilities of the EJV were critically reviewed and documented: fenestrations and double fenestrations, true or false duplications, triplication, absence, aberrant origin or course, or bifurcation. Tributaries of the EJV, such as the facial and posterior external jugular veins, are discussed. The internal jugular vein termination of the EJV is also presented. (4) Conclusions: Care should be taken when different morphological features of the EJV are encountered or reported.

Mechanisms of recurrent laryngeal nerve injury in endoscopic thyroidectomy for papillary thyroid carcinoma: A large data from China.

To investigate the mechanisms of recurrent laryngeal nerve (RLN) injury during endoscopic thyroidectomy via breast approach (ET-BA) in patients with papillary thyroid carcinoma (PTC). The records of 416 PTC patients who underwent ET-BA with intraoperative neural monitoring (IONM) from May 2015 to May 2021 in Beijing Friendship Hospital affiliated to Capital Medical University were retrospectively analyzed. All patients were women. Mean age was 37.80 (7.87) years. The ET-BA was performed in 416 patients. Overall incidence of RLN injury was 4.3% (18 patients). Injury was transient in 13 patients (3.1%) and permanent in five (1.2%). Macroscopic physical changes were apparent in the injured nerve in five patients (27.8%) and postoperative hoarseness or cough after drinking water were present in 11 (61.1%). Two RLN injuries occurred during nerve identification at the RLN laryngeal entry point into the surgical field, 15 during early nerve dissection somewhere between the first 0.5 and 2cm of the nerve's course through the surgical field, and one occurred distal to 2cm. The percentage of patients with separation, transection, traction and thermal mechanisms of injury was 27.8%, 22.2%, 22.2%, and 16.7%, respectively. The mechanism of injury was unknown in 11.1%. RLN injury may still occur during ET-BA despite endoscopic magnification and early nerve identification even when IONM is used. Separation, transection, and traction injuries were the most frequent causes of injury.

First demonstration of a novel nerve-targeting fluorophore in a cohort of ex vivo human tissues.

Iatrogenic nerve injury is a common complication across all surgical specialties. Better nerve visualization and identification during surgery will improve outcomes and reduce nerve injuries. The Gibbs Laboratory at Oregon Health and Science University has developed a library of near-infrared, nerve-specific fluorophores to highlight nerves intraoperatively and aid surgeons in nerve identification and visualization; the current lead agent is LGW16-03. Prior to this study, testing of LGW16-03 was restricted to animal models; therefore, it was unknown how LGW16-03 performs in human tissue. To advance LGW16-03 to clinic, we sought to test this current lead agent in ex vivo human tissues from a cohort of patients and determine if the route of administration affects LGW16-03 fluorescence contrast between nerves and adjacent background tissues (muscle and adipose). LGW16-03 was applied to ex vivo human tissue from lower limb amputations via two strategies: (1) systemic administration of the fluorophore using our first-in-kind model for fluorophore testing, and (2) topical application of the fluorophore. Results showed no statistical difference between topical and systemic administration. However, in vivo human validation of these findings is required.

Volar versus dorsal approach for supinator to posterior interosseous nerve transfer: An anatomical study in cadavers.

Supinator to posterior interosseous nerve (SPIN) transfer allows reconstruction of finger/thumb extension and thumb abduction for low radial nerve palsy, incomplete C6 tetraplegia, and brachial plexus injury affecting C7-T1. No study has compared dorsal versus volar approach to perform SPIN transfer. This comparison is studied in the present work, assessing supinator motor branch length and ability to achieve nerve transfer from either approach. Ten fresh frozen cadavers were randomly allocated to receive either a dorsal or volar approach to PIN and supinator radial and ulnar branches (RB=radial, UB=ulnar). Supinator head innervation patterns were documented. RB and UB lengths, forearm lengths measured from ulnar styloid to olecranon, visualization of extensor carpi radialis brevis (ECRB) motor nerve without additional dissection, and ability to perform tension-free nerve transfer were assessed. Nine of 10 specimens had supinator branches innervating both heads. The ECRB nerve was visualized in all volar but only one dorsal approach. No significant differences in forearm length were found. Volar with elbow extended: mean RB length was 35±7.8 mm and UB was 37.8±9.3 mm. Dorsal with elbow extended: mean RB length was 30±4.1 mm and UB was 38.8±7.3 mm. Dorsal with elbow flexed 90°: RB was 25.6±3.8 mm and UB was 34.8±4.8 mm. No significant differences were found in branch lengths between approaches (dorsal vs. volar UB, p=.339; dorsal vs. volar RB, p=.117). All limbs achieved tension-free coaptation. Neither approach demonstrated superiority in achieving tension-free nerve transfer. Volar permitted immediate identification of ECRB nerve whereas this was only visualized in one dorsal specimen without additional dissection. Overall, the volar approach allows direct coaptation in elbow extension, mimicking maximal physiologic tension for neurorrhaphy. It simultaneously permits additional procedures for pinch reconstruction via single exposure, circumventing limb/microscope maneuvering, dorsal dissection, and increased operative time. Ultimate choice of approach should depend on surgeon familiarity and potential need for additional simultaneous transfers.