Magnetic steering continuum robot for transluminal procedures with programmable shape and functionalities.

Millimeter-scale soft continuum robots offer safety and adaptability in transluminal procedures due to their passive compliance, but this feature necessitates interactions with surrounding lumina, leading to potential medical risks and restricted mobility. Here, we introduce a millimeter-scale continuum robot, enabling apical extension while maintaining structural stability. Utilizing phase transition components, the robot executes cycles of tip-based elongation, steered accurately through programmable magnetic fields. Each motion cycle features a solid-like backbone for stability, and a liquid-like component for advancement, thereby enabling autonomous shaping without reliance on environmental interactions. Together with clinical imaging technologies, we demonstrate the capability of navigating through tortuous and fragile lumina to transport microsurgical tools. Once it reaches larger anatomical spaces such as stomach, it can morph into functional 3D structures that serve as surgical tools or sensing units, overcoming the constraints of initially narrow pathways. By leveraging this design paradigm, we anticipate enhanced safety, multi-functionality, and cooperative capabilities among millimeter-scale continuum robots, opening new avenues for transluminal robotic surgery.

Assessment of changes in vessel area during needle manipulation in microvascular anastomosis using a deep learning-based semantic segmentation algorithm: A pilot study.

Appropriate needle manipulation to avoid abrupt deformation of fragile vessels is a critical determinant of the success of microvascular anastomosis. However, no study has yet evaluated the area changes in surgical objects using surgical videos. The present study therefore aimed to develop a deep learning-based semantic segmentation algorithm to assess the area change of vessels during microvascular anastomosis for objective surgical skill assessment with regard to the "respect for tissue." The semantic segmentation algorithm was trained based on a ResNet-50 network using microvascular end-to-side anastomosis training videos with artificial blood vessels. Using the created model, video parameters during a single stitch completion task, including the coefficient of variation of vessel area (CV-VA), relative change in vessel area per unit time (ΔVA), and the number of tissue deformation errors (TDE), as defined by a ΔVA threshold, were compared between expert and novice surgeons. A high validation accuracy (99.1%) and Intersection over Union (0.93) were obtained for the auto-segmentation model. During the single-stitch task, the expert surgeons displayed lower values of CV-VA (p < 0.05) and ΔVA (p < 0.05). Additionally, experts committed significantly fewer TDEs than novices (p < 0.05), and completed the task in a shorter time (p < 0.01). Receiver operating curve analyses indicated relatively strong discriminative capabilities for each video parameter and task completion time, while the combined use of the task completion time and video parameters demonstrated complete discriminative power between experts and novices. In conclusion, the assessment of changes in the vessel area during microvascular anastomosis using a deep learning-based semantic segmentation algorithm is presented as a novel concept for evaluating microsurgical performance. This will be useful in future computer-aided devices to enhance surgical education and patient safety.

Peri-implant soft tissue volume changes after microsurgical envelope technique with a connective tissue graft. A 5-year retrospective case series.

AIM: The aim of the present retrospective case series was to longitudinally assess soft tissue volume changes on the vestibular aspect of implants in relation to keratinized mucosa thickness (KMT) and width (KMW) after the application of the microsurgical envelope technique combined with a connective tissue graft (CTG). MATERIALS AND METHODS: A total of 12 healthy patients received 12 dental implants placed either in the posterior maxilla or mandible. The study involved the harvesting of 12 CTGs with a minimally invasive single-incision technique, grafted to the vestibular peri-implant soft tissue utilizing the envelope technique, followed by the insertion of 12 screw-retained IPS e.max crowns. RESULTS: The healing process was uneventful across all areas, and all patients were followed up for a period of 5 years. The evaluation of KMT showed the highest decrease in the first 6 weeks after surgery (5.5 ± 0.79 to 4.59 ± 0.62 mm), then dropped slightly to 4 ± 0.85 mm, after which it maintained at 4 ± 0.36 mm until the 2-year time point. Between the second and third years after surgery, a further decrease of 3.59 ± 0.42 mm was recorded for KMT, which then remained constant until the end of the 5-year research period. The observations regarding KMW were slightly different, with the measurements demonstrating the greatest decrease in first 6 weeks (from 2.5 ± 0.42 to 1.5 ± 0.42 mm), which was maintained until the 1-year time point. Between the first and second years after surgery, the KMW increased to 2 ± 0.60 mm and remained level for the next 3 years, at 2 ± 0.85 mm. CONCLUSIONS: The current research demonstrated the advantages of using a combination of a minimally invasively harvested CTG and the microsurgical envelope technique for a duration of 5 years.

Microsurgical reconstruction for head and neck in patients with end-stage renal disease undergoing dialysis.

INTRODUCTION: Free flap transfer for head and neck defects has gained worldwide acceptance. Because flap failure is a devastating outcome, studies have attempted to identify risk factors-including renal failure. We sought to determine whether end-stage renal disease (ESRD) patients undergoing dialysis are at increased risk of flap failure following microsurgical head and neck reconstruction. PATIENTS AND METHODS: The study's participants were patients who underwent free flap reconstruction in the head and neck region at Hualien Tzu Chi Hospital between January 2010 and December 2019. We used the National Health Insurance "Specific Diagnosis and Treatment Code" to identify patients undergoing dialysis; these patients comprised the dialysis group, whose members were matched to a non-dialysis group for age and gender. The dependent variables were flap survival rate, take-back rate, and flap failure risk between the dialysis and non-dialysis groups. RESULTS: We included 154 patients in the dialysis (n = 14) and non-dialysis (n = 140) groups. The groups were similar in terms of age and most comorbidities, except diabetes mellitus, hypertension, and coronary artery disease, which were more prevalent in the dialysis group. The dialysis and non-dialysis groups had similar flap survival rates (100% vs. 92.9%; p = .600). Twenty-three patients underwent take-back surgery, most in the non-dialysis group (14.3% vs. 15.0%; p = 1.000). Patients in the dialysis group were more likely to have prolonged intensive care unit stays; however, dialysis alone did not predict flap failure (OR: 0.83; p = .864). CONCLUSION: This study found no significant differences in free flap survival and take-back rates between patients with and without dialysis. Dialysis did not increase the risk of flap failure following microsurgical head and neck reconstruction in this study; however, prospective, randomized controlled trials are needed.

The value of microvascular breast reconstruction: Cost equivalence of TRAM and DIEP flaps implications in the era of CMS reforms.

BACKGROUND: Recent CMS billing changes have raised concerns about insurance coverage for deep inferior epigastric perforator (DIEP) flap breast reconstruction. This study compared the costs and utilization of transverse rectus abdominis myocutaneous (TRAM), DIEP, and latissimus dorsi (LD) flaps in breast reconstruction. METHOD: The study utilized the National Inpatient Sample database to identify female patients who underwent DIEP, TRAM, and LD flap procedures from 2016 to 2019. Key data such as patient demographics, length of stay, complications, and costs (adjusted to 2021 USD) were analyzed, focusing on differences across the flap types. RESULTS: A total of 17,770 weighted patient encounters were identified, with the median age being 51. The majority underwent DIEP flaps (73.5%), followed by TRAM (14.2%) and LD (12.1%) flaps. The findings revealed that DIEP and TRAM flaps had a similar length of stay (LOS), while LD flaps typically had a shorter LOS. The total hospital charges to costs using cost-to-charge ratio were also comparable between DIEP and TRAM flaps, whereas LD flaps were significantly less expensive. Factors such as income quartile, primary payer of hospitalization, and geographic region significantly influenced flap choice. CONCLUSION: The study's results appear to contradict the prevailing notion that TRAM flaps are more cost-effective than DIEP flaps. The total hospital charges to costs using cost-to-charge ratio and hospital stays associated with TRAM and DIEP flaps were found to be similar. These findings suggest that changes in the insurance landscape, which may limit the use of DIEP flaps, could undermine patient autonomy while not necessarily reducing healthcare costs. Such policy shifts could favor less costly options like the LD flap, potentially altering the landscape of microvascular breast reconstruction.

A review of 10 patients treated with the masquelet technique and microsurgical technique combined for Gustilo type III open tibial fractures.

BACKGROUND: Open tibial fractures often include severe bone loss and soft tissue defects and requires complex reconstructive operations. However, the optimal treatment is unclear. METHODS: This retrospective study enrolled patients with Gustilo type III open tibial fractures from January 2018 to January 2021 to assess the clinical utility of Masquelet technique together with microsurgical technique as a combined strategy for the treatment of open tibial fractures. The demographics and clinical outcomes including bone union time, infection, nonunion and other complications were recorded for analysis. The bone recovery quality was evaluated by the AOFAS Ankle-Hindfoot Scale score and the Paley criteria. RESULTS: We enrolled 10 patients, the mean age of the patients and length of bone defects were 31.7 years (range, 23-45 years) and 7.5 cm (range, 4.5-10 cm) respectively. Bone union was achieved for all patients, with an average healing time of 12.2 months (range, 11-16 months). Seven patients exhibited a bone healing time of less than 12 months, whereas 3 patients exhibited a bone healing time exceeding 12 months. No significant correlation was found between the length of bone loss and healing time. In addition, no deep infection or nonunion was observed, although 2 patients experienced wound fat liquefaction with exudates and 1 patient presented with a bloated skin flap. The average AOFAS Ankle-Hindfoot Scale score was 80.5 (range, 74-85), and all patients were evaluated as good or exellent based on the Paley criteria. CONCLUSIONS: Our study indicated that the use of the Masquelet technique and the microsurgical technique as a combined strategy is safe and effective for the treatment of Gustilo type III open tibial fractures.

Microsurgical treatment of ophthalmic artery aneurysm, a case series of 55 patients with long-term follow-up.

BACKGROUND: Ophthalmic artery aneurysm (OAA) can be secured in endovascular or microsurgical approaches. Still there are controversies in technique selection and their long term outcomes. METHODS: All the patients with OAA were treated microsurgically and followed. Demographic data, neurological status, physical examination findings, angiographic data, operation details, and intraoperative and postoperative events were recorded and analyzed. P < 0.05 was considered significant. RESULTS: Among 55 patients, 38 were females (69.1%). Median preoperative glasgow coma scale (GCS), Fisher Grade, and Hunt and Hess(HH) scores were 15, 1 and 1, respectively. The most common neurologic manifestation was visual problems (n = 15). The most common anatomical projection was medial (43.6%) oriented lesions. 85.5% of them only had 1 ophthalmic aneurysm while multiple aneurysms were reported in 14.6%. In 52 patients temporary clip was used. in 21 patients (38.2%) intraoperative aneurysm rupture occurred. Larger aneurysm size and preoperative hydrocephalus were associated with higher rates of aneurysm rupture (P = 0.003 and 0.031). 28.5% of the patients with visual problems had clinical improvement in the postoperative period. The mean follow-up period was 5 years. Follow-up angiography showed a 100% obliteration rate with a 0.0% recurrence rate. Median values for follow-up glasgow outcome scale and modified Rankin scale were 5 and 0, respectively. favorable neurological outcomes were associated with better primary GCS and HH scores. CONCLUSION: OAA microsurgery is an effective and safe procedure with significant improvement in both visual and neurological status. Low recurrence rate and excellent clinical recovery are the most important advantages of microsurgery in OAA treatment.

A microscope in your pocket: can smartphones be used to perform microsurgery?

PURPOSE: To evaluate the use of the latest generation smartphone camera in performing arterial microanastomosis in rats. METHODS: Ten Wistar rats were divided into 2 groups and underwent anastomosis of the right carotid artery with the aid of magnification from a microscope (group M) and a smartphone camera (group S), to compare patency in 72 hours, as well as to measure the weight of the animals, diameter of the carotid arteries and anastomosis time. RESULTS: There was no statistical difference between the weight of the animals or the diameter of the carotid arteries. There was a statistical difference for the time spent on anastomoses, which was greater in group S, with higher rates of thrombosis (p < 0.05). CONCLUSIONS: Although our patency and anastomosis time results were statistically lower in the smartphone group, there was success in some cases. As the segment continues to progress, it is likely that the results will improve in line with the evolution of camera technology.

Transfer learning for anatomical structure segmentation in otorhinolaryngology microsurgery.

BACKGROUND: Reducing the annotation burden is an active and meaningful area of artificial intelligence (AI) research. METHODS: Multiple datasets for the segmentation of two landmarks were constructed based on 41 257 labelled images and 6 different microsurgical scenarios. These datasets were trained using the multi-stage transfer learning (TL) methodology. RESULTS: The multi-stage TL enhanced segmentation performance over baseline (mIOU 0.6892 vs. 0.8869). Besides, Convolutional Neural Networks (CNNs) achieved a robust performance (mIOU 0.8917 vs. 0.8603) even when the training dataset size was reduced from 90% (30 078 images) to 10% (3342 images). When directly applying the weight from one certain surgical scenario to recognise the same target in images of other scenarios without training, CNNs still obtained an optimal mIOU of 0.6190 ± 0.0789. CONCLUSIONS: Model performance can be improved with TL in datasets with reduced size and increased complexity. It is feasible for data-based domain adaptation among different microsurgical fields.

Cognition in children with arachnoid cysts - A five-year follow-up after microneurosurgical fenestration.

BACKGROUND AND PURPOSE: In recent years there has been a re-evaluation regarding the clinical implications of temporal lobe arachnoid cysts (temporal arachnoid cysts) in children. These cysts have often been considered asymptomatic, or if symptomatic, only causing focal neurological symptoms or signs of increased intracranial pressure. However, several studies have more recently reported on cognitive symptoms improving after surgery. This study aimed to evaluate if reported cognitive improvement after surgery of temporal arachnoid cysts were stable after five years. METHOD: Ten consecutive children (m = 14.65; range 12.1-19.415 were assessed cognitively five years after micro-neurosurgical fenestration of a temporal arachnoid cyst. Results were compared to results from their pre- and post-surgical evaluations. Evaluations included the Wechsler-scales, Boston Naming Test (BNT), Rey Auditory Verbal Learning Test (RAVLT), verbal fluency test (FAS) and Rey Complex Figure Test (RCFT). RESULTS: The analysis revealed significant postsurgical improvement compared to baseline on the Wechsler-scales measures of general intelligence (FSIQ), verbal abilities (VCI) and processing speed (PSI). Mean differences after surgery were 8.3 for FSIQ, (p = 0.026), 8.5 for VI (p = < .01) and 9.9 for PSI (p = 0.03). There were no significant differences in mean test results when comparing postsurgical scores with scores five years after surgery, indicating long-term stability of improvements. CONCLUSION: The results indicate that affected cognitive functions in children with temporal arachnoid cysts improve after surgery and that the improvements remain stable five years later. The improvements and long term stability were also consistent with the experience of both parents and children. The findings provide a strong argument for neurosurgical fenestration of temporal arachnoid cysts in children.

Can we improve time to patency with vasoepididymostomy with an innovative epididymal occlusion stitch?

INTRODUCTION: Obstructive azoospermia occurs when there is a blockage in the male reproductive tract, leading to a complete absence of sperm in the ejaculate. It constitutes around 40% of all cases of azoospermia (1, 2). Blockages in the male reproductive tract can arise from either congenital or acquired factors, affecting various segments such as the epididymis, vas deferens, and ejaculatory ducts (3). Examples of congenital causes encompass conditions like congenital bilateral absence of the vas deferens and unexplained epididymal blockages (4). Acquired instances of obstructive azoospermia may result from factors like vasectomy, infections, trauma, or unintentional injuries caused by medical procedures (5). This complex condition affecting male fertility, presents two main treatment options: microsurgical reconstruction and surgical extraction of sperm followed by in vitro fertilization (IVF). Microsurgical reconstruction proves to be the most cost-effective option for treating obstructive azoospermia when compared with assisted reproductive techniques (6, 7). However, success rates of reconstruction defined by patency are as high as 99% for vasovasostomy (VV) but decline to around 65% if vasoepididymostomy (VE) is required (8, 9). Thus, continued refinement in technique is necessary in order to attempt to improve patency for patients undergoing VE. In this video, we show a comprehensive demonstration of microsurgical VE, highlighting the innovative epididymal occlusion stitch. The goal of this innovative surgical technique is to improve outcomes for VE. MATERIALS AND METHODS: The patient is a 39-year-old male diagnosed with obstructive azoospermia who presents for surgical reconstruction via VE. His partner is a 37-years-old female with regular menstrual cycles. The comprehensive clinical data encompasses a range of factors, including FSH levels, results from semen analysis, and outcomes from testicular sperm aspiration. This thorough exploration aims to provide a thorough understanding of our innovative surgical technique and its application in addressing complex cases of obstructive azoospermia. RESULTS: The procedure was started on the right, the vas deferens was identified and transected. The abdominal side of the vas was intubated and a vasogram performed, there was no obstruction. There was no fluid visible from the testicular side of the vas for analysis, thus we proceeded with VE. Upon inspection of the epididymis dilated tubules were identified. After selecting a tubule for VE, two 10-0 nylon sutures were placed, and it was incised. Upon inspection of the fluid motile sperm was identified. After VE, we performed a novel epididymal occlusion stitch technique. This was completed distal to the anastomosis by placing a 7-0 prolene through the tunica of the epididymis from the medial to lateral side. This stitch was then tightened down with the goal to largely occlude the epididymis so that sperm will preferentially travel through the anastomosis. The steps were then repeated on the left. At 3-month follow up, the patient had no change in testicular size as compared with preoperative size (18cc), he had no testicular or incisional discomfort, and on semen analysis he had presence of motile sperm. After 3 months post-surgery, the patient had motile sperm seen on semen analysis. DISCUSSION: The introduction of a novel epididymal occlusion stitch demonstrates a targeted strategy to enhance the success of microscopic VE. Encouragingly, a 3-month post-surgery follow-up reveals the presence of motile sperm, reinforcing the potential efficacy of our approach. This is promising given the historical lower patency, delayed time to patency, and higher delayed failure rates that patients who require VE experience (10). In total, 40% of all azoospermia cases can be attributed to obstruction. The conventional treatments for obstructive azoospermia involve microsurgical reconstruction and surgical sperm retrieval followed by IVF. While microsurgical reconstruction has proven to be economically viable, the quest for enhanced success rates has led to the exploration of innovative techniques. Historically, the evolution of VV and VE procedures, initially performed in the early 20th century, laid the foundation for contemporary microsurgical approaches (11). Notably, the microscopic VV demonstrated significant improvements in patency rates and natural pregnancy likelihood, as evidenced by the seminal Vasovastomy Study Group study in 1991 (8). In contemporary literature, success rates particularly for VE remain unchanged for the past three decades since the original published success rates by the Vasectomy Reversal Study Group (12). VE is associated with a longer time to patency as well with patients taking 2.8 to 6.6 months to have sperm return to ejaculate as compared to 1.7 to 4.3 months for those undergoing VV. Additionally, of those patients who successfully have sperm return to the ejaculate after VE up to 50% will have delayed failure compared to 12% for those undergoing VV who are patent. Finally, of those who experience delayed failure after undergoing VE it usually occurs earlier with studies reporting as early as 6 months post-operatively (10). Given the lack of improvement and significantly worsened outcomes with VE further surgical refinement is a constant goal for surgeons performing this procedure. CONCLUSION: In conclusion, this video is both a demonstration and a call to action for commitment to surgical innovation. We aim to raise the bar in VE success rates, ultimately bringing tangible benefits to patients and contributing to the ongoing evolution of reproductive medicine. The novel epididymal occlusion stitch emerges as a beacon of progress, promising not only enhanced safety but also potential reductions in patency time. Surgical excellence and methodological refinement, as exemplified in this video, lay the foundation for a future where male reproductive surgery continues to break new ground.

Robotic and Plastic Surgery: actuality and prospects for the near future, a scoping review.

OBJECTIVE: This work aims to review the existing use of robotics in plastic surgery. METHODS: A meticulous selection process identified 22 articles relevant to this scoping review. RESULTS: The literature on the use of robotics in plastic surgery is sparse. Nonetheless, this review highlights emerging benefits in microsurgery, breast reconstruction, and transoral surgery. CONCLUSION: This scoping review identifies critical articles reporting the emerging use of robotics in plastic surgery. While the scientific medical community has yet to extensively document its use, the available evidence suggests a promising future for robotics in this field.

Clinical outcomes of posterior fossa arteriovenous malformations: a single center experience.

BACKGROUND: Posterior fossa arterio-venous malformations (pfAVMs) are challenging lesions due to the anatomical particularities of the posterior fossa, and the high incidence of hemorrhagic presentation. The two most important goals when treating AVMs are preserving neurological function and preventing rupture, or a second hemorrhage. The aim of this study was to analyze the clinical and imaging features of pfAVMs to identify the factors that influence the prognosis of these patients. METHODS: We conducted a single-center retrospective observational study that included patients treated at our institution with pfAVMs between January 1997 and December 2021. RESULTS: A total of 48 patients were included. A good modified Rankin score (mRS) was observed in 33 cases (69%) at presentation. Thirty-four patients (71%) presented with a ruptured AVM. Out of these, 19 patients (40%) had intraventricular hemorrhage. Microsurgical resection was performed in 33 cases (69%), while in the other cases, the patients opted for conservative management (7 cases, 15%), stereotactic radiosurgery (SRS) (6 cases, 12%), or endovascular treatment (2 cases, 4%). Patients ≤ 30 years old were more prone to hemorrhagic presentation (OR: 5.23; 95% CI: 1.42-17.19; p = 0.024) and this remained an independent risk factor for rupture after multivariate analysis as well (OR: 4.81; 95% CI: 1.07-21.53; p = 0.040). Following multivariate analysis, the only factor independently associated with poor prognosis in the surgically treated subgroup was a poor clinical status (mRS 3-5) at admission (OR: 96.14; 95% CI: 5.15-1793.9; p = 0.002). CONCLUSIONS: Management of posterior fossa AVMs is challenging, and patients who present with ruptured AVMs often have a poor clinical status at admission leading to a poor prognosis. Therefore, proper and timely management of these patients is essential.

Transoral laser exoscopic surgery of the larynx: state of the art and comparison with traditional transoral laser microsurgery.

Objective: To evaluate the efficacy of transoral laser exoscopic surgery (TOLES) in a unicentric series of patients affected by benign and malignant glottic and supraglottic lesions, and compare outcomes with those of transoral laser microsurgery (TOLMS). Methods: To demonstrate the non-inferiority of TOLES in terms of operative time, margin status and complication rates, we compared outcomes of 93 patients treated by TOLES between July 2021 and July 2023 with those of a match-paired group of 107 historical patients treated by TOLMS. To perform a multiparametric ergonomic evaluation of TOLES vs TOLMS, we used observational methods for biomechanical overload risk assessment and wearable technologies comparing 15 procedures with TOLES vs a paired match of 13 surgeries performed with TOLMS by the same surgeon. Results: No significant differences were found in terms of surgical duration, positive margins, or complications between TOLES and TOLMS. Ergonomics assessment by inertial measurement units and electromyographic surface electrodes demonstrated a reduced biomechanical overload with TOLES compared to TOLMS. Conclusions: The many advantages of TOLES, such as its superior didactic value, better digital control of light even through small-bored laryngoscopes, improved binocular vision, and increase in surgical performance by 3 or 4-hand techniques, are difficult to be quantified. In contrast, its non-inferiority in terms of oncological results and better ergonomics compared to TOLMS are demonstrated herein.

Robot-assisted lymphovenous anastomosis surgery for lymphocele in the groin.

We present the first-in-human robot-assisted microsurgery on a lymphocele in the groin involving a man in his late 60s who had been coping with the condition for 12 months. Despite numerous efforts at conservative treatment and surgical intervention, the lymphocele persisted, leading to a referral to our clinic.Diagnostic techniques, including indocyanine green lymphography and ultrasound, identified one lymphatic vessel draining into the lymphocele. The surgical intervention, conducted with the assistance of a robot and facilitated by the Symani Surgical System (Medical Microinstruments, Calci, Italy), involved a lymphovenous anastomosis and excision of the lymphocele. An end-to-end anastomosis was performed between the lymphatic and venous vessels measuring 1 mm in diameter, using an Ethilon 10-0 suture.The surgery was successful, with no postoperative complications and a prompt recovery. The patient was discharged 3 days postoperatively and exhibited complete recovery at the 14-day follow-up. This case marks the first use of robot-assisted microsurgical lymphovenous anastomosis to address a groin lymphocele, highlighting the benefit of advanced robotic technology in complex lymphatic surgeries.

Repeat Radiosurgery for Sporadic Vestibular Schwannoma After Primary Radiosurgical Failure: An International Multi-institutional Investigation.

OBJECTIVE: To describe outcomes of patients with sporadic vestibular schwannoma (VS) who underwent repeat stereotactic radiosurgery (SRS) after primary SRS failure. STUDY DESIGN: Multi-institutional historical cohort study. SETTING: Five tertiary care referral centers. PATIENTS: Adults ≥18 years old with sporadic VS. INTERVENTION: Primary and repeat treatment with SRS. MAIN OUTCOME MEASURE: Microsurgery-free survival after repeat SRS. RESULTS: Across institutions, 32 patients underwent repeat SRS after primary SRS. Most patients (74%) had tumors with cerebellopontine angle extension at primary SRS (median size, 13.5 mm [interquartile range, 7.5-18.8] mm). After primary SRS, patients underwent repeat SRS at a median of 4.8 years (interquartile range, 3.2-5.7 yr). For treatment modality, 30 (94%) patients received gamma knife for primary treatment and 31 (97%) patients received gamma knife as their repeat treatment. Median tumor volume increased from 0.970 cm3 at primary SRS to 2.200 cm3 at repeat SRS. Facial nerve function worsened in two patients after primary SRS and in two patients after repeat SRS. There were no instances of intracranial complications after repeat SRS. Microsurgery-free survival rates (95% confidence interval; number still at risk) at 1, 3, and 5 years after repeat SRS were 97% (90-100%, 24), 84% (71-100%, 13), and 68% (48-96%, 6), respectively. There was one occurrence of malignancy diagnosed after repeat radiosurgery. CONCLUSION: Overall, repeat SRS for sporadic VS has comparable risk profile, but lower rates of tumor control, compared with primary SRS.

Clinical Application of the 4K-3D Exoscope System in Cochlear Implantation.

PURPOSE: To evaluate a system for otomicrosurgery based on 4K three-dimensional (3D) exoscope technology and apply it to cochlear implantation. METHODS: An open stereoscopic vision-based surgical system, which differs from traditional surgical microscopes, was created by utilizing 4K stereo imaging technology and combining it with low-latency 4K ultra-high-definition 3D display. The system underwent evaluation based on 57 cochlear implantation operations, three designed microscopic manipulations, and a questionnaire survey. RESULTS: The surgical images displayed by the 4K-3D exoscope system (4K-3D-ES) are stereoscopic, clear, and smooth. The use of 4K-3D-ES in cochlear implantation is not inferior to traditional microscopes in terms of intraoperative bleeding and surgical complications, and the surgical duration is not slower or may even be faster than when using traditional microscopes. The results of micromanipulation experiments conducted on 16 students also confirmed this and demonstrated that 4K-3D-ES can be easily adapted. Furthermore, additional advantages of 4K-3D-ES were gathered. Significantly enlarged and high-definition stereoscopic images contribute to the visualization of finer anatomical microstructures such as chordae tympani, ensuring safer surgery. Users feel more comfortable in their necks, shoulders, waists, and backs. Real-time shared stereoscopic view for multiple people, convenient for collaboration and teaching. The ear endoscope and 4K-3D-ES enable seamless switching on the same screen. High-definition 3D images and videos can be saved with just one click, making future publication and communication convenient. CONCLUSION: The feasibility and safety of 4K-3D-ES for cochlear implantation surgery have been demonstrated. The 4K-3D-ES also offers numerous unique advantages and holds clinical application and promotional value.