Virtual Surgical Planning and Three-Dimensional Models for Precision Sinonasal and Skull Base Surgery

Sinonasal and skull base malignancies represent a rare, heterogenous group of pathologies with an incidence of 0.556 per 100,000 persons in the population. Given the numerous critical anatomic structures located adjacent to the sinonasal cavity and skull base, surgery for tumors in this region requires careful pre-operative planning with the assistance of radiological imaging and intraoperative image guidance technologies to reduce the risk of complications. Virtual surgical planning (VSP) and three-dimensional models (3DMs) are adjunctive technologies which assist clinicians to better visualize patient anatomy using enhanced digital radiological images and physical stereolithographic models based on patients' personal imaging. This review summarizes our institutional experience with VSP and 3DMs in sinonasal and skull base surgical oncology. A clinical case series is used to thematically illustrate the application of VSP and 3DMs in surgical ablation, reconstruction, patient communication, medical education, and interdisciplinary teamwork in sinonasal and skull base surgery.

Comparison between an Operating Surgical Microscope and High Magnification Surgical Loupes in Microvascular Reconstruction of Head and Neck Defects in a Tertiary Healthcare Centre

Introduction and Objective

Microvascular free tissue transfers have become an important method of reconstruction following head & neck oncological resection. The objective of this study was to evaluate the efficacy of surgical loupes against surgical operating microscope, which is the gold standard for microvascular anastomosis and also to explore the possibility of surgical loupes as an essential cost-effective armamentarium in head and neck reconstruction.

Materials and Methods

This prospective randomized study included 40 patients diagnosed with head and neck malignancies, requiring microvascular free flap reconstruction. A total of 20 patients who underwent free flap reconstruction following oncologic/maxillofacial defects using high magnification surgical loupes & the other 20 patients were subjected to reconstruction under an operating surgical microscope. The efficacy was assessed based on the following parameters. 1. Total operating time taken for completing anastomosis. 2. Overall fatigue. 3. Free flap failure rate.

Results

The microscope group took an overall mean time of 34.26 min considering its limited degree of freedom in adjusting intraoperatively whereas the loupes group had a shorter mean anastomosis time 33.29 min considering its ease of operator adjustability. Overall, fatigue was compared using Mann-Whitney Test and found to be statistically significant with P value of 0.17, the loupe group was found to be better with mean score of 6.90 in 21 patients than microscope with mean score of 6.21in 19 patients. Flap survival rate in the loupe group had two cases of venous obstruction at 24 h follow-up and microscope group had 1 case of venous.obstruction.

Conclusion

The success with loupe only free tissue transfer can be attributable considering expertise with the microscope and the loupes can be a cost-effective alternative to microscope.

Scapular free flap as a good choice for mandibular reconstruction: 119 out of 280 cases after resection of oral squamous cell carcinoma in a single institution

Microsurgical procedures for reconstruction after resection of head and neck tumours have become standardised and reliable. Among them, the scapular free flap is used less often, mostly to avoid excessive operating times. We hypothesise that complex reconstructions after resection of oral squamous cell carcinoma (OSCC) are successful even with time-consuming free flaps such as the scapular free flap. In this retrospective, single-centre study, we used the evaluation of medical records to investigate the postoperative outcome of microvascular reconstruction after ablative surgery of OSCC. Associations among the categorical variables were analysed using Pearson's chi squared test or Fisher's exact test. Among the continuous variables, the t test or Mann-Whitney U test were used as appropriate. For multivariate analysis, the logistic regression model was calculated. In the sample of 280 free flap reconstructions, we performed 142 radial forearm and 119 scapular free flaps. The American Society of Anesthesiology (ASA) score (p=0.006) and the duration of the operation (p=0.010) are independent factors which influence the need for operative revisions. The type of free flap is irrelevant for that. With 4.2% flap losses, scapular free flaps were successful; even in patients ≥ 70 years old (0 flap losses). Complex reconstructions after surgical resection of OSCC are successful even in aged patients. The scapular free flap is a good choice for mandibular reconstruction despite the time-consuming intraoperative repositioning of the patient. In an increasingly ageing group of patients, who have more vascular diseases, scapular free flaps could be a very successful alternative after ablative surgery of oral squamous cell carcinoma.

Venous thromboembolism in head and neck cancer surgery

Background

Venous thromboembolism (VTE) is a major cause of perioperative morbidity and mortality. Historically, otolaryngology surgery has been seen as very low risk of VTE, given the relatively short procedures and healthy patient population. However, head and neck surgery patients have multiple additional risk factors for VTE compared to general otolaryngology patients, and only recently has research been directed at examining this population of patients regarding VTE risk.

Review

VTE has long been recognized as a major issue in other surgical specialties, with VTE rates of 15–60 % in some specialties in the absence of prophylaxis with either mechanical compression or anticoagulation. Multiple large-scale retrospective studies have shown that the incidence of VTE in otolaryngology patients is quite low, ranging between 0.1 and 1.6 %. However, these studies indicated that head and neck cancer patients may have an increased risk of VTE. Further retrospective studies focusing on head and neck cancer patients found a VTE rate of approximately 2 %, but one study also found a suspected VTE rate of 5.6 % based on clinical symptoms, indicating that retrospective studies may underreport the true incidence. A single prospective study found a 13 % risk of VTE after major head and neck surgery. Furthermore, risk stratification using the Caprini risk assessment model demonstrates that the highest risk patients may have a VTE risk of 18.3 %, although this may be lowered (but not eliminated) through the use of appropriate prophylactic anticoagulation.

Conclusion

VTE is likely a more significant concern in head and neck surgery patients than previously realized. Appropriate prophylaxis with mechanical compression and anticoagulation is essential; risk stratification may serve as a useful tool to identify head and neck cancer patients at highest risk for VTE.