Trends in Endoscopic and Microscopic Approaches to Transsphenoidal Pituitary Surgery in the US.

OBJECTIVES: Among the transsphenoidal (TSS) approaches to pituitary tumors, the microscopic approach (MA) has historically been the predominant technique with the increasing adoption of the endoscopic approach (EA). This study investigates national trends in TSS approaches and postoperative outcomes for MA and EA through 2021. METHODS: The TriNetX database was queried for patients undergoing TSS (MA and EA) between 2010 and 2021. Data were collected on demographics, geographic distribution of surgical centers, postoperative complications, stereotactic radiosurgery (SRT), repeat surgery, and postoperative emergency department (ED) visits. RESULTS: 8644 TSS cases were queried between 2010 and 2021. MA rates were highest until 2013 when rates of EA (52%) surpassed MA (48%) and continued to increase through 2021 (81%). From 2010 to 2015 EA had higher odds of a postoperative CSF leak (OR 3.40) and diabetes insipidus (DI (OR 2.30)) versus MA (p < 0.05); from 2016 to 2021 differences were not significant. Although there was no significant difference among approaches from 2010 to 2015 for syndrome of inappropriate antidiuretic hormone (SIADH), hyponatremia, or bacterial meningitis, from 2016 to 2021 EA had lower odds of SIADH (OR 0.54) and hyponatremia (OR 0.71), and higher odds of meningitis (OR 1.79) versus MA (p < 0.05). EA had higher odds of additional surgery (either EA or MA) after initial surgery from 2010 to 2021. From 2010 to 2015 EA had lower odds of postoperative SRT compared to MA, whereas in 2016-2021 there was no statistical difference among approaches. CONCLUSION: This study demonstrates increasing EA adoption for TSS in the United States since 2013. Complication rates have overall improved for EA compared to MA, potentially as a result of improving surgeon familiarity and experience. LEVEL OF EVIDENCE: 4 Laryngoscope, 133:2135-2140, 2023.

Selection of Optimal Functional Lymphatic Vessel Cutoff Size in Supermicrosurgical Lymphaticovenous Anastomosis in Lower Extremity Lymphedema.

BACKGROUND: Functional lymphatic vessels are essential for supermicrosurgical lymphaticovenous anastomosis. Theoretically, the larger the lymphatic vessel, the better the flow. However, large lymphatic vessels are not readily available. Since the introduction of lymphaticovenous anastomosis, no guidelines have been set as to how small a lymphatic vessel is still worthwhile for anastomosis. METHODS: In this longitudinal cohort study, unilateral lower limb lymphedema patients who underwent lymphaticovenous anastomosis between March of 2016 and January of 2019 were included. Demographic data and intraoperative findings including the number and size of lymphatic vessels were recorded. The cutoff size was determined by receiver operating characteristic curve analysis, based on the functional properties of lymphatic vessels. Clinical correlation was made with post-lymphaticovenous anastomosis volume measured by magnetic resonance volumetry. RESULTS: A total of 141 consecutive patients (124 women and 17 men) with a median age of 60.0 years (range, 56.7 to 61.2 years) were included. The cutoff size for a functional lymphatic vessel was determined to be 0.50 mm (i.e., lymphatic vessel0.5) from a total of 1048 lymphatic vessels. Significant differences were found between the number of lymphatic vessels0.5 anastomosed (zero to one, two to three, and greater than over equal to four lymphatic vessels0.5), the median post-lymphaticovenous anastomosis volume reduction (in milliliters) (p < 0.001), and the median percentage volume reduction (p = 0.012). CONCLUSIONS: Lymphatic vessel0.5 can be a valuable reference for lymphaticovenous anastomosis. Post-lymphaticovenous anastomosis outcome can be enhanced with the use of lymphatic vessel0.5 for anastomoses. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, II.

A Protocol for Performing Reconstructive Microsurgery on Patients With COVID-19.

On March 11, 2020, the World Health Organization declared COVID-19 to be a pandemic, challenging health care systems all over the world. National health care systems have reorganized to cope with the disease. Surgical services departments around the world have been affected and elective surgical procedures have been postponed to conserve medical resources. When a patient with COVID-19 requires an urgent microsurgical free flap due to trauma or a tumor, personnel from the health care facility must have a protocol in place to follow for the patient's care and follow-up. In this article, we present our protocol for patients with COVID-19 requiring reconstructive microsurgery.

3D digital image microscope system-assisted vasovasostomy and vasoepididymostomy in rats.

Optimal vision and ergonomics are essential factors contributing to the achievement of good results during microsurgery. The three-dimensional (3D) digital image microscope system with a better 3D depth of field can release strain on the surgeon's neck and back, which can improve outcomes in microsurgery. We report a randomized prospective study of vasoepididymostomy and vasovasostomy using a 3D digital image microscope system (3D-DIM) in rats. A total of 16 adult male rats were randomly divided into two groups of 8 each: the standard operating microscope (SOM) group and the 3D-DIM group. The outcomes measured included the operative time, real-time postoperative mechanical patency, and anastomosis leakage. Furthermore, a user-friendly microscope score was designed to evaluate the ergonomic design and equipment characteristics of the microscope. There were no differences in operative time between the two groups. The real-time postoperative mechanical patency rates were 100.0% for both groups. The percentage of vasoepididymostomy anastomosis leakage was 16.7% in the SOM group and 25.0% in the 3D-DIM group; however, no vasovasostomy anastomosis leakage was found in either group. In terms of the ergonomic design, the 3D-DIM group obtained better scores based on the surgeon's feelings; in terms of the equipment characteristics, the 3D-DIM group had lower scores for clarity and higher scores for flexibility and adaptivity. Based on our randomized prospective study in a rat model, we believe that the 3D-DIM can improve surgeon comfort without compromising outcomes in male infertility reconstructive microsurgery, so the 3D-DIM might be widely used in the future.

Automated Vision-Based Microsurgical Skill Analysis in Neurosurgery Using Deep Learning: Development and Preclinical Validation.

BACKGROUND/OBJECTIVE: Technical skill acquisition is an essential component of neurosurgical training. Educational theory suggests that optimal learning and improvement in performance depends on the provision of objective feedback. Therefore, the aim of this study was to develop a vision-based framework based on a novel representation of surgical tool motion and interactions capable of automated and objective assessment of microsurgical skill. METHODS: Videos were obtained from 1 expert, 6 intermediate, and 12 novice surgeons performing arachnoid dissection in a validated clinical model using a standard operating microscope. A mask region convolutional neural network framework was used to segment the tools present within the operative field in a recorded video frame. Tool motion analysis was achieved using novel triangulation metrics. Performance of the framework in classifying skill levels was evaluated using the area under the curve and accuracy. Objective measures of classifying the surgeons' skill level were also compared using the Mann-Whitney U test, and a value of P < 0.05 was considered statistically significant. RESULTS: The area under the curve was 0.977 and the accuracy was 84.21%. A number of differences were found, which included experts having a lower median dissector velocity (P = 0.0004; 190.38 ms-1 vs. 116.38 ms-1), and a smaller inter-tool tip distance (median 46.78 vs. 75.92; P = 0.0002) compared with novices. CONCLUSIONS: Automated and objective analysis of microsurgery is feasible using a mask region convolutional neural network, and a novel tool motion and interaction representation. This may support technical skills training and assessment in neurosurgery.

Stroke Microsurgical Thrombectomy Human Placenta Simulator.

BACKGROUND: Stroke microsurgical cerebrovascular thrombectomy reports are limited, although this technique could be used in many centers as a primary treatment or a salvage intervention option. It requires great ability, so our aim is to describe and validate a stroke microsurgical thrombectomy ex vivo simulator with operative nuances analysis. METHODS: Human placenta (HP) models simulated middle cerebral artery vessels with intraluminal thrombus to be microsurgically excised. Six neurosurgeons performed 1-mm and 2-mm longitudinal and transverse arteriotomy in different arteries to remove a 1.5-cm length thrombus. Validation through construct validity compared time to complete the task, complete vessel cleaning, vessel manipulation, vessel stenosis, and leakage in both techniques. RESULTS: All 6 HP models reproduced with fidelity stroke microsurgical thrombectomy, so participants completed 24 sessions, 4 for each neurosurgeon on the same model in different arteries. Construct validity highlighted microsurgical technical difficulties with positive results obtained by parameters variation during performance. Transverse arteriotomy with 1-mm length had best results (P < 0.05) allowing complete thrombus removal, less stenosis, and minor leakage in abbreviated time. CONCLUSIONS: A HP simulator can reproduce with high fidelity all stroke microsurgical thrombectomy part tasks. Transverse 1-mm arteriotomy followed by thrombectomy and 2 simple sutures can fulfill all quality assurance aspects in such intervention accordingly to training model, due to easier vessel opening, complete thrombus removal, no stenosis, and faster microsuture.

Hands-free Adjustment of the Microscope in Microneurosurgery.

BACKGROUND: In microneurosurgery, the operating microscope plays a vital role. The classical neurosurgical operation is bimanual, that is, the microsurgical instruments are operated with both hands. Often, operations have to be carried out in narrow corridors at the depth of several centimeters. With current technology, the operator must manually adjust the field of view during surgery-which poses a disruption in the operating flow. Until now, technical adjuncts existed in the form of a mouthpiece to move the stereo camera unit or voice commands and foot pedals to control other interaction tasks like optical configuration. However, these have not been widely adopted due to usability issues. This study tests 2 novel hands-free interaction concepts based on head positioning and gaze tracking as an attempt to reduce the disruption during microneurosurgery and increase the efficiency of the user. METHODS: Technical equipment included the Pentero 900 microscope (Carl Zeiss Microscopy GmbH, Jena, Germany), HTC Vive Pro (HTC, Taoyuan District (HQ), Taiwan), and an inbuilt 3D-printed target probe. Eleven neurosurgeons including 7 residents and 4 consultants participated in the study. The tasks created for this study were with the intention to mimic real microneurosurgical tasks to maintain applicative accuracy while testing the interaction concepts. The tasks involved visualization system adjustment to the specific target and touching the target. The first trial was conducted in a virtual reality setting applying the novel hands-free interaction concepts, and the second trial was conducted performing the same tasks on a 3D-printed target probe using manual field of view adjustment. The participants completed both trials with the same predetermined tasks, in order to validate the feasibility of the novel technology. The data collected for this study were obtained with the help of review protocols, detailed post-trial interviews, video and audio recordings, along with time measurements while performing the tasks. RESULTS: The user study conducted at the Charité Hospital in Berlin found that the gaze-tracking and head-positioning- based microscope adjustment were 18% and 29% faster, respectively, than the classical bimanual adjustment of the microscope. Focused user interviews showed the users' proclivity for the new interaction concepts, as they offered minimal disruption between the simultaneous target selection and camera position adjustment. CONCLUSIONS: The hands-free interaction concepts presented in this study demonstrated a more efficient execution of the microneurosurgical tasks than the classical manual microscope and were assessed to be more preferable by both residents and consultant neurosurgeons.

End-to-Side Microvascular Anastomosis on Rat Femoral Vessels Using Only 2-Throw Knot Interrupted Sututres - Evaluation of Feasibility and Patency Rates on Rat Femoral Vessels Model.

BACKGROUND: The use of a 3-throw knot for anastomosis by microvascular neurosurgeons is the usual standard. There is an inherent belief that the third throw adds extra security to the knot; however, the third throw can make the knot heavy and unbalanced and can exert undue extra pressure on the opposing walls of the small-caliber intracranial vessels. This study evaluated the feasibility and efficiency of 2-throw reef knot interrupted sutures for an end-to-side microvascular anastomosis. METHODS: A prospective observational study of end-to-side anastomosis using a femoral artery-to-vein model was performed in 30 Sprague-Dawley rats. All anastomoses were done using 2-throw reef knot interrupted sutures. Ten procedures each were done by the heel-first, toe-first, and classic 2-ends techniques. Individual parameters were recorded for analysis. The delayed patency was confirmed by reexploration after a mean duration of 19.82 ± 8.12 days. RESULTS: The overall patency rates were 100% in the immediate period and 96.43% (27 of 28) in the delayed period. The average clamping time, average suturing time, and the average time per suture were 65.48 ± 16.93 minutes, 40.94 ± 11.22 minutes, and 3.18 ± 1.10 minutes, respectively. Two rats died in the postoperative period. CONCLUSIONS: The end-to-side microvascular anastomosis with 2-throw reef knots is feasible, with excellent immediate and delayed patency rates.

Percutaneous Transforaminal Endoscopic Discectomy Versus Open Microdiscectomy for Lumbar Disc Herniation: A Systematic Review and Meta-analysis.

STUDY DESIGN: Systematic review and meta-analysis. OBJECTIVE: To give a systematic overview of effectiveness of percutaneous transforaminal endoscopic discectomy (PTED) compared with open microdiscectomy (OM) in the treatment of lumbar disk herniation (LDH). SUMMARY OF BACKGROUND DATA: The current standard procedure for the treatment of sciatica caused by LDH, is OM. PTED is an alternative surgical technique which is thought to be less invasive. It is unclear if PTED has comparable outcomes compared with OM. METHODS: Multiple online databases were systematically searched up to April 2020 for randomized controlled trials and prospective studies comparing PTED with OM for LDH. Primary outcomes were leg pain and functional status. Pooled effect estimates were calculated for the primary outcomes only and presented as standard mean differences (SMD) with their 95% confidence intervals (CI) at short (1-day postoperative), intermediate (3-6 months), and long-term (12 months). RESULTS: We identified 2276 citations, of which eventually 14 studies were included. There was substantial heterogeneity in effects on leg pain at short term. There is moderate quality evidence suggesting no difference in leg pain at intermediate (SMD 0.05, 95% CI -0.10-0.21) and long-term follow-up (SMD 0.11, 95% CI -0.30-0.53). Only one study measured functional status at short-term and reported no differences. There is moderate quality evidence suggesting no difference in functional status at intermediate (SMD -0.09, 95% CI -0.24-0.07) and long-term (SMD -0.11, 95% CI -0.45-0.24). CONCLUSION: There is moderate quality evidence suggesting no difference in leg pain or functional status at intermediate and long-term follow-up between PTED and OM in the treatment of LDH. High quality, robust studies reporting on clinical outcomes and cost-effectiveness on the long term are lacking.Level of Evidence: 2.

Optimizing biliary outcomes in living donor liver transplantation: Evolution towards standardization in a high-volume center.

Biliary complications have always been a dreaded cause of morbidity after living donor liver transplantation. While intrinsic variations in both graft and recipient biliary anatomy remain a significant factor to the difficulty of biliary reconstruction, our institution has taken advantage of its high volume of cases to critically review and evaluate modifiable operative risk factors, in particular, our surgical protocols. We present herein, the evolution of our reconstructive biliary technique from conventional methods to our current standard of microsurgical biliary reconstruction for both graft and recipient ducts. Over this period of transition, our center has created a classification system for biliary reconstruction that decreased the biliary complication rates from 40.0% to 10.2%.

Comparison of surgical outcomes of free flap reconstructions performed by expert microsurgeons and trainees who completed a structured microsurgical training program in a teaching hospital.

BACKGROUND: Few studies have evaluated clinical outcomes of novice surgeons trained in a microsurgical training program. Herein, we describe successful free flap reconstructions performed by trainees who completed a structured microsurgical training program. METHODS: The Microsurgical Skills Training Course, a laboratory-based structured microsurgical training program, was developed and used for microsurgical training. Three trainees (postgraduate years 6 and 7) who completed the training course during residency were assigned to perform free flap reconstructions between March 2015 and February 2019. Clinical outcomes of free flap reconstruction were assessed. A retrospective propensity-score-matched analysis was performed between the trainee and expert microsurgeon groups. RESULTS: A total of 161 patients were included. Of them, 67 (25 of the trainee group and 42 of the expert group) were propensity score-matched. No flap failure developed in either matched group (p>0.999). Rates of overall complications, partial flap loss, and emergent reoperation due to vascular compromise were not significantly different between the two groups (p=0.384, p=0.525, and p=0.322, respectively), whereas those of donor complications and overall operation time were significantly higher in the trainee group than the expert group (p=0.002 and p<0.001, respectively). CONCLUSION: The use of a structured microvascular training program in qualified teaching hospitals may help trainees achieve independence as microsurgeons and favorable clinical outcomes.

Trends in endoscopic and microscopic transsphenoidal surgery: a survey of the international society of pituitary surgeons between 2010 and 2020.

PURPOSE: This comparative survey of surgical practice patterns between 2010 and 2020 aims to elicit trends in practice patterns for transsphenoidal surgery and to identify areas for improvement. METHODS: Web-based surveys were sent to the International Society of Pituitary Surgeons via a membership listserv in 2010 and 2020. These 33-item surveys collected information on demographics, surgical approach, perceived advantages and disadvantages, and recommendations for improvements. Statistical analyses were conducted using the Mann-Whitney U test for continuous variables and Fisher's exact test for categorical variables. RESULTS: There were 51 respondents in 2010 and 82 respondents in 2020. The majority were full-time academic surgeons from the United States or Europe. Preference for a purely endoscopic technique increased from 43% in 2010 to 87% in 2020. Preference for routinely working with an otolaryngologist or second neurosurgeon increased from 35 to 51%. Most surgeons (74%) reported that they were more likely to achieve a greater extent of resection with the endoscope, though 51% noted increased operating time. The most commonly rated advantage (34%) of endoscopic TSS was fewer postoperative nasoseptal perforations; the most commonly (34%) rated disadvantage was more postoperative complications, including cerebrospinal fluid leak. Respondents were divided on whether microscopic TSS should continue to be taught in residency. Many (32%) advocated for improved endoscopic instrumentation and team training. CONCLUSION: Endoscopic TSS is now the clearly preferred method for surgery amongst a cohort of higher-volume academic neurosurgeons. This trend is likely to continue, and this provides guidelines for future training.

The end game - A quantitative assessment tool for anastomosis in simulated microsurgery.

With the move towards simulation based microsurgical training and emphasis on the declining usage of animal models, there is a need for an objective method to evaluate microvascular anastomosis in a non-living, simulated microsurgical training environment. Our aim was to create a validated assessment tool to evaluate the intimal surface of the end product to measure skills acquisition. The intimal surface of 200 anastomoses from 23 candidates and 2 experts were assessed using ImageJ to measure 4 parameters: 1) distance between the distal insertion points, 2) distance between the proximal insertion points, 3) length of sutures placed, 4) number of axes. Using these parameters, a 9-component scoring system was produced based on the hypothesis of the ideal anastomosis having equidistance between the above parameters. The scoring system was devised based on population performance to give a maximum score of 100. The EPIA tool demonstrated its ability to differentiate between seniority from undergraduate to expert. Furthermore, predictive validity was shown by demonstrating skill acquisition between day 3 and 5 of the microsurgery course. The EPIA tool is a valid and feasible method to assess and provide feedback regarding the end product as an adjunct to current scoring systems in simulated microsurgery.

Achieving balance between resident autonomy and patient safety: Analysis of resident-led microvascular reconstruction outcomes at a microsurgical training center with an established microsurgical training pathway.

BACKGROUND: With advances in microsurgery, the published success rate of microsurgical reconstruction by experienced microsurgeons is greater than 95%. However, it is unknown whether the training residents can produce similar results. At our county hospital, residents perform and lead all aspects of microsurgical reconstruction, from raising the flap to performing microanastomoses. In this study, we retrospectively reviewed the outcomes of 156 consecutive microsurgical cases to determine the efficacy and safety of resident-led reconstructions at the county hospital. METHODS: We performed a retrospective review of patients who underwent microsurgical reconstruction at the county hospital from 2016 to 2018. Demographic, surgical procedure, flap characteristics, resident levels, and complication data were collected. RESULTS: Of the 156 free tissue flaps performed, the most commonly performed reconstruction was for the breast (62.8%), followed by lower extremity (15.9%), upper extremity (10.6%), head and neck (8.8%), and genitalia (1.8%). The average procedure time was 525.1 ±â€¯149.2 min, and mean ischemia time for each flap was 69.8 ±â€¯42.2 min. Venous anastomoses were performed by PGY3 (0.96%), PGY4 (27.9%), PGY5 (18.3%), and PGY6 (47.1%), while the arterial anastomoses were performed by PGY4 (16.4%), PGY5 (11.0%), and PGY6 (69.2%). The average number of anastomosis attempts was 1.3, with a range of 1 to 6. The overall flap success rate was 95.5% with a takeback rate of 7.1%. CONCLUSIONS: In conclusion, our analysis shows that resident-led reconstruction can achieve similar microsurgical success as that of published outcomes. We believe resident-led microsurgical reconstruction can be safely performed, with as-needed faculty assistance in high-risk and complicated cases, while allowing resident education and maturation of technical and decision-making skills.

Surgery as a Viable Alternative First-Line Treatment for Prolactinoma Patients. A Systematic Review and Meta-Analysis.

CONTEXT: The improved remission and complication rates of current transsphenoidal surgery warrant reappraisal of the position of surgery as a viable alternative to dopamine agonists in the treatment algorithm of prolactinomas. OBJECTIVE: To compare clinical outcomes after dopamine agonist withdrawal and transsphenoidal surgery in prolactinoma patients. METHODS: Eight databases were searched up to July 13, 2018. Primary outcome was disease remission after drug withdrawal or surgery. Secondary outcomes were biochemical control and side effects during dopamine agonist treatment and postoperative complications. Fixed- or random-effects meta-analysis was performed to estimate pooled proportions. Robustness of results was assessed by sensitivity analyses. RESULTS: A total of 1469 articles were screened: 55 (10 low risk of bias) on medical treatment (n = 3564 patients) and 25 (12 low risk of bias) on transsphenoidal surgery (n = 1836 patients). Long-term disease remission after dopamine agonist withdrawal was 34% (95% confidence interval [CI], 26-46) and 67% (95% CI, 60-74) after surgery. Subgroup analysis of microprolactinomas showed 36% (95% CI, 21-52) disease remission after dopamine agonist withdrawal, and 83% (95% CI, 76-90) after surgery. Biochemical control was achieved in 81% (95% CI, 75-87) of patients during dopamine agonists with side effects in 26% (95% CI, 13-41). Transsphenoidal surgery resulted in 0% mortality, 2% (95% CI, 0-5) permanent diabetes insipidus, and 3% (95% CI, 2-5) cerebrospinal fluid leakage. Multiple sensitivity analyses yielded similar results. CONCLUSIONS: In the majority of prolactinoma patients, disease remission can be achieved through surgery, with low risks of long-term surgical complications, and disease remission is less often achieved with dopamine agonists.