Outside Europe.

This chapter illustrates that cranial surgery was not limited to Europe. There was however no contribution to improving knowledge outside Europe until medical science departed for the Arab world.

Thickness and design features of clinical cranial implants-what should automated methods strive to replicate?

PURPOSE: New deep learning and statistical shape modelling approaches aim to automate the design process for patient-specific cranial implants, as highlighted by the MICCAI AutoImplant Challenges. To ensure applicability, it is important to determine if the training data used in developing these algorithms represent the geometry of implants designed for clinical use. METHODS: Calavera Surgical Design provided a dataset of 206 post-craniectomy skull geometries and their clinically used implants. The MUG500+ dataset includes 29 post-craniectomy skull geometries and implants designed for automating design. For both implant and skull shapes, the inner and outer cortical surfaces were segmented, and the thickness between them was measured. For the implants, a 'rim' was defined that transitions from the repaired defect to the surrounding skull. For unilateral defect cases, skull implants were mirrored to the contra-lateral side and thickness differences were quantified. RESULTS: The average thickness of the clinically used implants was 6.0 ± 0.5 mm, which approximates the thickness on the contra-lateral side of the skull (relative difference of -0.3 ± 1.4 mm). The average thickness of the MUG500+ implants was 2.9 ± 1.0 mm, significantly thinner than the intact skull thickness (relative difference of 2.9 ± 1.2 mm). Rim transitions in the clinical implants (average width of 8.3 ± 3.4 mm) were used to cap and create a smooth boundary with the skull. CONCLUSIONS: For implant modelers or manufacturers, this shape analysis quantified differences of cranial implants (thickness, rim width, surface area, and volume) to help guide future automated design algorithms. After skull completion, a thicker implant can be more versatile for cases involving muscle hollowing or thin skulls, and wider rims can smooth over the defect margins to provide more stability. For clinicians, the differing measurements and implant designs can help inform the options available for their patient specific treatment.

Flap loss in head and neck reconstruction: Is there a singular cause for failure?

Despite the high success rates reported in head and neck reconstruction, free flap failures continue to persist. Understanding the factors associated with flap loss and improving overall success are paramount. This study aimed to comprehensively assess the factors influencing flap revision and free tissue transfer survival in head and neck reconstruction. The study included 70 patients with defects in the lower two-thirds of the head and neck region and underwent reconstruction using free flaps. Patient age, gender, smoking status, comorbidities and data on the location and aetiology of the defect, the specific type of flap employed, the recipient artery and vein chosen, instances of revision and the overall success of the flap were collected. The investigation aimed to establish correlations between these variables as well as flap success and revision rates. No statistically significant differences were observed in arterial and venous anastomosis revision rates, or flap survival, in relation to variables such as age, gender, flap type, smoking status, comorbidities, recipient artery or vein and the number of vein anastomoses. The malignant tumour group exhibited a lower requirement for arterial revision and a higher flap survival rate compared to the benign tumour group. This study underscores the comparable safety profiles of perforator-based and conventional flaps in head and neck reconstruction. Furthermore, it reveals that patient characteristics are not contraindications for free tissue transfer. Additionally, the quantity of the veins and choice of recipient vessels are flexible and do not significantly impact flap success. The higher rates of flap success in patients with malignant aetiology requires further investigation.

Evaluating Head and Neck Reconstruction Outcomes Proves Difficult-Seeking Improvement in Reporting.

This Viewpoint advocates for the improvement of the quality of head and neck reconstruction studies through accurate depictions of the defect and reconstruction performed.

[Repaired four cases of hypopharyngeal combined neck skin defects using a folded supraclavicular flap].

Objective:To evaluate the outcomes following the use of folded supraclavicular flap repaired hypopharyngeal combined neck skin defects. Methods:Folded supraclavicular flap were designed to repaired four cases of hypopharyngeal combined neck skin defects patients. Evaluate their repair effect （3 men,1 woman; mean age:66 years）. Hypopharyngeal fistula from 3.2 cm×1.8 cm to 4.5 cm×3.8 cm,skin defects in the neck from 3.8 cm×2.2 cm to 5.1 cm×4.5 cm. The folded supraclavicular flap from 8 cm×5 cm to 13 cm×9 cm. Results:All flaps survived, head and neck appearance was satisfactory, and no patient experienced a major complication. All patients resumed an oral diet function. No fistula recurrence or stricture developed after 6-19 months of follow-up. Conclusion:The folded supraclavicular flap is a safe and effective flap Repaired for hypopharyngeal combined neck skin defects.

Use of supermicrosurgery in craniofacial and head and neck soft tissue reconstruction: a systematic review of the literature and meta-analysis.

Supermicrosurgery is an evolving approach in the reconstruction of head and neck (HN) and craniofacial (CF) defects. This systematic review aims to evaluate the use of supermicrosurgery for arterial or combined arterial and venous anastomoses in the reconstruction of HN and CF soft tissue defects, and the associated success, total complication, and reoperation rates. A literature search was conducted on PubMed, Dynamed, DARE, EMBASE, Cochrane, and British Medical Journal (BMJ) electronic databases (PROSPERO ID: CRD42023476825). Nine studies fulfilled the inclusion criteria with 35 patients who underwent soft tissue reconstructive procedures using supermicrosurgery. Twenty-one flaps were performed on 20 patients (57.1%) with the remaining 15 patients (42.9%) undergoing supermicrosurgical replantation. The most common pathology requiring reconstruction was HN trauma (n = 16, 45.7%) followed by malignancy (n = 15, 42.9%). The pooled success rate for supermicrosurgery was 98% (95% CI 90 to 100, p = 1.00; I2 = 0%). The cumulative complication rate across all the studies was 46% (95% CI 13 to 80, p < 0.01; I2 = 0%), and the pooled rate of reoperation was 1% (95% CI 0 to 8, p = 0.23; I2 = 24%). The use of supermicrosurgery for HN and CF soft tissue reconstruction has an overall success rate of 98%, which is commensurate with traditional microsurgery for HN reconstruction. Complication and reoperation rates are comparable to previous literature. This study confirms the feasibility of supermicrosurgery as a safe and reliable reconstructive option for HN and CF defects.

Is hardware colonization associated with latent hardware complications and removal in maxillomandibular free flap reconstruction?

BACKGROUND: The relationship between hardware colonization, latent hardware complications, and hardware removal remains unclear following osteocutaneous free flap reconstruction of the jaws. METHODS: Retrospective cohort study of all patients undergoing free flap reconstruction of the maxilla or mandible from 2016 to 2021. RESULTS: A total of 240 subjects were included. Hardware colonization was associated with latent hardware complication in bivariate (p ≤ 0.001) and multivariate analysis (p ≤ 0.001). Time to latent hardware complication was 6.87 months earlier in colonized subjects (p ≤ 0.001). Of the 35 subjects undergoing hardware removal, 25 initiated but failed conservative therapy, and resolution of symptoms was achieved in 24 subjects after one operative intervention and 33 subjects after repeat intervention if indicated. CONCLUSIONS: Hardware colonization increases the risk and onset of latent hardware complication. Prompt hardware removal may improve outcomes by leading to faster resolution of symptoms without the burden and cost of conservative therapies.

Novel Clinical Anatomical Consideration of the Superficial and Deep Layers of the Deep Temporal Fascia.

BACKGROUND: The deep temporal fascia provides anchoring during thread lifting, which is a minimally invasive face-lifting procedure. However, anatomical studies involving the deep temporal fascia in addition to effective and safe thread-lifting procedures are scarce. The authors clarified the anatomy of the superficial layer of the deep temporal fascia and its surrounding structure using ultrasonography, histologic sections, and cadaveric dissection to propose an effective thread-lifting procedure guideline. METHODS: The authors included 20 healthy young participants from the Republic of Korea. Real-time, two-dimensional, B-mode ultrasonography was performed. Longitudinal scanning was performed along three vertical lines: the line passing through the jugale, the anterior margin of the condylar process of the mandible, and the midpoint between the jugale and anterior margin of the condylar process. Histologic samples from three fresh adult cadavers were harvested from 2.5 cm above and below the zygomatic arch. Eighteen fresh adult hemifaces of cadavers from the Republic of Korea (six men and three women, aged 67.3 ± 7.2 years) were used to confirm the morphology of the deep temporal fascia. RESULTS: The superficial layer of the deep temporal fascia crossed the zygomatic arch and was connected to the origin of the zygomaticus major muscle at the line passing through the jugale. The superficial layer continued inferiorly to the parotidomasseteric fascia at the line passing through the midpoint and condylar process of the mandible. CONCLUSION: This study yielded the novel anatomy of the superficial layer of the deep temporal fascia, and this anatomical structure may be used for an ideal thread-lifting procedure.

Greater Saphenous Vein Graft Harvest from Anterolateral Thigh Free Flap Incision: A Novel Technique.

The greater saphenous vein can be harvested from the standard incision for an anterolateral free flap and used as a vein graft in complex head and neck reconstruction. Laryngoscope, 134:648-650, 2024.

Novel Hybrid Technique for Preservation of Frontal Branch of Facial Nerve: Subgaleal Preinterfascial Dissection.

OBJECTIVE: The pterional approach is the workhorse of skull-base neurosurgery, which allows virtual access to any intracranial lesion around the circle of Willis. Preserving the frontotemporal branch of the facial nerve and conserving the temporal muscle's symmetry are fundamental objectives besides the access that can be obtained through this versatile neurosurgical technique. This manuscript proposes a subgaleal preinterfascial dissection, a novel hybrid technique that provides advantages of previously described temporal muscle dissection techniques while preserving the integrity of facial nerve branches and the unobstructed broad pterional region. We describe the subgaleal preinterfascial dissection as a safe and simple to technique to achieve preservation of the facial nerve frontal branches during anterolateral approaches. METHODS: Two cadaveric heads were skillfully dissected and studied to perform a proper subgaleal preinterfascial dissection on both sides of each cadaver. Afterward, the same technique was employed in 108 patients during a pterional approach for different neurosurgical diseases, with a postoperative follow-up of 6 months. RESULTS: None of the 108 patients presented postoperative frontotemporal branch palsy during postoperative follow-up. Likewise, no complications related to the proposed technique were present. CONCLUSIONS: The subgaleal preinterfascial dissection is a reliable, safe technique that may be employed during a pterional approach with an unobstructed surgical view and excellent cosmetic and functional results, preserving the frontotemporal branch of the facial nerve.

Management of Persistent Syringomyelia in Patients Operated for Chiari Malformation Type 1.

BACKGROUND: The treatment of persistent syringomyelia associated with Chiari malformation type 1 (CM1) is unclear. This study aims to evaluate the clinical and radiologic outcomes of syringo-subarachnoid shunt (SSS) as a treatment for persistent syringomyelia following posterior fossa decompression (PFD) for CM1. METHODS: Forty-nine cases treated for CM1 associated syringomyelia at a single center were analyzed, 17 of them undergoing reoperation due to persistent syrinx formation. The patients' demographic data, neurologic presentations, and radiologic results were analyzed, including cerebellar herniation, posterior fossa volume, the level at which the syrinx started and finished, the size and diameter of the syrinx. RESULTS: Seventeen patients underwent SSS placement, with 1 minor surgical complication (a cerebrospinal fluid leak) occurring and requiring revision. No morbidity or mortality was observed. Among these 17 reoperated patients, partial or complete resorption of the syrinx was observed in all cases. The results suggest that if the syrinx diameter is >10 mm at its thickest point, extends for more than 10 vertebrae, and starts from the upper cervical region and extends to the upper thoracic region, the syrinx may not regress after the first surgery and potentially predicting the need for a second operation before PFD. CONCLUSIONS: SSS placement for persistent syrinx following PFD for CM1 is a safe and effective surgical treatment method. These criteria may also help predict the need for a second surgery and the overall disease outcome for both the surgeon and patient.

Facial Masculinization Surgery: An Analysis of Interest Trends Using Search Term Analysis.

INTRODUCTION: Facial masculinization surgery (FMS) is increasingly popular among cisgender and transgender men. The benefits of FMS are focused on facial identity and have been proven to decrease gender dysphoria in this population. Previous research showed increasing interest in gender affirmation surgery and facial feminization surgery, but the prevalence of FMS has not been explored. It is difficult to find these data based on surgical records alone because institutions do not have standardized methods of reporting and lack publications in the field. Our study aimed to analyze public interest in FMS by using worldwide Google Trends to quantify these trends. METHODS: A worldwide Google Trends search was completed from January 1, 2008, to December 31, 2022, for terms focused on FMS. Then, search terms were analyzed for nonfacial masculinization procedures and were aggregated. Lastly, a PubMed search was conducted for the terms "transgender" and "facial masculinization" from January 1, 2008, to December 31 st , 2022, to compare publication rates. RESULTS: Our data showed an increasing interest in FMS through Google search trends since the year 2008. A similar trend was demonstrated for non-FMS gender-affirming terms. PubMed analysis showed "transgender" medicine publishing rates were approximately 39.65 times greater than "facial masculinization" publishing rates, although "facial masculinization" medicine did produce a positive trend over the study period of approximately 4 publications per year. The medical literature on transgender surgeries rapidly outpaces publications specifically focusing on FMS. CONCLUSION: Our study showed increasing interest in gender affirmation surgery over time, particularly FMS. These increasing trends should encourage greater scientific exploration of FMS and research to properly quantify and assess surgical outcomes in this special population. Additional educational interventions for both the general public and medical providers, to increase awareness of unique challenges that impact this community and highlight changes in health care coverage over time, should be created to keep pace with increasing patient demand and address the physical, systemic, and psychosocial issues faced by people who identify as transgender.

Turbocharging as a strategy to boost extended perforator flap vascularity in head and neck reconstruction-A report of two cases.

Perforator flap has been applied as the most common flap for soft tissue defect reconstruction. Here, we presented two cases using turbocharging procedure of perforator to perforator as a salvage strategy. The first case was a 54-year-old male with recurrent squamous cell carcinoma (SCC) in the left buccal area and mouth floor. A 6 × 22 cm posteromedial thigh (PMT) flap was designed for reconstruction. The two eccentric perforators of the PMT flap could not conjoin together during dissection nearby the main pedicle of profunda femoral artery (PFA) resulting in inadequate perfusion. Side branched stump before clipped the branch of distal perforator was preserved, then the proximal perforator was divided and end-to-end anastomosis of side branch of distal perforator was done successfully. The second case was a 52-year-old male underwent wide composite excision of right tongue SCC. After excision, anterolateral thigh (ALT) flap around 7 × 15 cm was harvested from left thigh and two perforators were included which one tiny perforator supplied by the descending branch (DB) and the other major perforator originated from oblique branch (OB) of lateral circumflex femoral artery (LCFA). However, the OB main perforator injury showed inadequate perfusion of flap. We trimmed the injury zone of OB perforator, and shift to re-anastomosis of OB perforators to side branch of DB of LCFA directly. The flap demonstrated excellent perfusion immediately after the operation, and it exhibited complete survival 2 weeks postoperatively. These results indicated that the turbocharging procedure, from perforator to perforator, could serve as a strategy for salvaging perfusion-compromised flaps, especially in cases of eccentric perforators or perforator injury resulting in inadequate perfusion.

Observing vessel stumps axially: A novel exoscope for end-to-end microvascular anastomosis.

Although many free tissue transfers have been performed, free flap loss can still occur because of vascular compromise. To facilitate microsurgery, we invented the axial-view microscope (aMS), a new type of microscope that can axially visualize vessel stumps. The aMS was combined with an optical microscope, the so-called bird's-eye-view microscope (bMS). Using our aMS, we observed the cross-sections of the following 12 arteries during vascular anastomosis: three deep inferior epigastric arteries, three suprathyroid arteries, two thoracodorsal arteries, two jejunal arteries, one lateral circumflex femoral artery, and one facial artery. For each artery, we measured the vessel height-to-width (H-W) ratio to determine the roundness of the vessel stump. Based on the aMS and bMS, the average H-W ratios were 0.877 ± 0.187 and 0.445 ± 0.172, respectively. The H-W ratio obtained using the aMS was significantly higher than that of the bMS (P < 0.001). Providing the surgeon with a bidirectional view of the vessel stump reduced blind spots at the anastomotic site. In this report, we describe our new microscope and associated clinical cases.

Systematic review of the free thoracodorsal artery perforator flap for head and neck reconstruction.

BACKGROUND: The thoracodorsal artery perforator (TDAP) flap has gained interest as a option for reconstruction of head and neck defects while minimizing donor site morbidity as compared to traditional workhorse flaps. The primary aim of this systematic review is to assess the postoperative outcomes and efficacy of this flap. METHODS: Several databases were screened for relevant citations. The quality of studies and risk of bias were evaluated using the MINORS scoring system. RESULTS: Twenty articles containing 168 patients undergoing at least one TDAP flap reconstruction met the inclusion criteria. There were no incidences of total flap failure and only 10 incidences of partial flap failure (5.95 %). Flap complications and donor site morbidity was low. The average MINORS score of the studies suggested a moderately high amount of bias. CONCLUSIONS: Based on limited quality evidence, this review suggests that TDAP flap is a safe and feasible option for head and neck reconstruction with comparable success rates as other commonly used flaps, with low complication rate and donor site morbidity. Further large-scale studies are warranted.

Co-surgery in head and neck microvascular reconstruction.

PURPOSE: Co-surgery with two attending reconstructive surgeons is becoming increasingly common in breast microvascular reconstruction due to case complexity and the potential for improved outcomes and operative efficiency. The impact of co-surgery on outcomes in head and neck microvascular reconstruction has not been studied. METHODS: Our multidisciplinary head and neck reconstruction team (Otolaryngology, Plastic Surgery) at the University of Pittsburgh transitioned to a practice of co-surgery on head and neck free flaps. In this study, we compare outcomes of two surgeon head and neck reconstruction to single surgeon reconstruction in a prospectively maintained database. RESULTS: 384 patients met our inclusion criteria from 2020 to 2022. Cases were performed by a single surgeon in 77.8 % of cases (299/384) and two surgeons in 22.1 % (85/384). The mean age was 62.5 years. There was no difference between the single surgeon cohort and the co-surgery cohort in terms of flap survival, procedure time, ischemia time, hospital length of stay, recipient site complications, or rates of return to the operating room. Donor site complications were less common in the co-surgery cohort (0 % vs 4.7 %, p = 0.021). For our reconstructive team, the transition to co-surgery has increased total surgeon fee collection per free flap by 28 % and increased surgeon flap related RVU production by 35 %. CONCLUSION: Co-surgery is feasible and safe in head and neck microvascular reconstruction. Benefits may include reduced complications, increased reimbursement, and improved interdisciplinary collaboration.

[Accurate tissue flap reconstruction method based on the quadratic surface developability for head and neck soft tissue defects].

Soft tissue defects resulting from head and neck tumor resection seriously impact the physical appearance and psychological well-being of patients. The complex curvature of the human head and neck poses a formidable challenge for maxillofacial surgeons to achieve precise aesthetic and functional restoration after surgery. To this end, a normal head and neck volunteer was selected as the subject of investigation. Employing Gaussian curvature analysis, combined with mechanical constraints and principal curvature analysis methods of soft tissue clinical treatment, a precise developable/non-developable area partition map of the head and neck surface was obtained, and a non-developable surface was constructed. Subsequently, a digital design method was proposed for the repair of head and neck soft tissue defects, and an in vitro simulated surgery experiment was conducted. Clinical verification was performed on a patient with tonsil tumor, and the results demonstrated that digital technology-designed flaps improved the accuracy and aesthetic outcome of head and neck soft tissue defect repair surgery. This study validates the feasibility of digital precision repair technology for soft tissue defects after head and neck tumor resection, which effectively assists surgeons in achieving precise flap transplantation reconstruction and improves patients' postoperative satisfaction.

A novel approach to microsurgical teaching in head and neck surgery leveraging modern 3D technologies.

The anatomically complex and often spatially restricted conditions of anastomosis in the head and neck region cannot be adequately reproduced by training exercises on current ex vivo or small animal models. With the development of a Realistic Anatomical Condition Experience (RACE) model, complex spatial-anatomical surgical areas and the associated intraoperative complexities could be transferred into a realistic training situation in head and neck surgery. The RACE model is based on a stereolithography file generated by intraoperative use of a three-dimensional surface scanner after neck dissection and before microvascular anastomosis. Modelling of the acquired STL file using three-dimensional processing software led to the model's final design. As a result, we have successfully created an economical, sustainable and realistic model for microsurgical education and provide a step-by-step workflow that can be used in surgical and general medical education to replicate and establish comparable models. We provide an open source stereolithography file of the head-and-neck RACE model for printing for educational purposes. Once implemented in other fields of surgery and general medicine, RACE models could mark a shift in medical education as a whole, away from traditional teaching principles and towards the use of realistic and individualised simulators.