Virtual surgical planning for maxillary reconstruction with the scapular free flap: An evaluation of a simple cutting guide design.

BACKGROUND: The study's objective is to assess the feasibility and utility of VSP for maxillary reconstruction with the scapular free flap. METHODS: An open-source VSP platform was used to create the reconstruction models and simple guides. Clinical, operative, and postoperative data were collected. RESULTS: Ten patients in the VSP cohort and 18 in the non-VSP control cohort were included in the study. There was a significant reduction in operative time (256.0 ± 69.4 vs. 448.1 ± 108.2 min, p < 0.01), tracheotomy rate (20% vs. 72%, p < 0.01), increased two-team utilization rate (80% vs. 0%, p < 0.01) and better reconstructive accuracy (7.5 ± 3.4 vs. 11.7 ± 7.6 mm, p = 0.048) for the VSP cohort. CONCLUSIONS: Maxillary reconstruction planned with an in-house open-source VSP platform and accompanied simple guides can facilitate a two-team approach, reduce operative time, and improve structural accuracy. This open-source technology has great potential to be readily applied in other institutions to improve efficiency and outcomes.

Postoperative patient-centered multimedia education in head and neck cancer patients: A pilot study.

Objective: It is hypothesized that patients who are actively provided with more treatment-related education may report increased satisfaction and have improved overall outcomes. The aim of this study was to demonstrate the feasibility of an audiovisual education platform in patients undergoing head and neck surgery and to investigate whether patients using this module reported increased satisfaction. Methods: This was a prospective pilot study of patients undergoing major head and neck reconstructive surgery who were randomized to either (1) control group or (2) intervention (i.e., in-patient audiovisual educational module). Both study groups then completed a discharge survey. Results: Total 35 patients were recruited into the study (N = 16 Intervention; N = 19 Control). Patients in the intervention group reported an increased satisfaction with their overall outcome. Exactly 87.5% (14 of 16) found the intervention to be "Extremely useful," "Quite useful," or "Sometimes useful." Exactly 68.8% (11 of 16) would recommend similar patients to receive the same educational intervention. However, there was no significant difference in patients' perceived level of involvement amongst the two groups. For future improvements to the intervention, patients requested further information such as how to look after themselves, postoperative radiation, course in hospital, and nutrition. Conclusion: This pilot study demonstrated the feasibility of an audiovisual education platform in the postoperative setting for patients undergoing major head and neck reconstructive surgery. Although most patients found the module useful, future steps will incorporate patient feedback to further improve the educational platform and confirm the current preliminary impressions in prospective studies. Level of Evidence: 1b.

Benefits of Patient-Specific Reconstruction Plates in Mandibular Reconstruction Surgical Simulation and Resident Education.

Poorly contoured mandibular reconstruction plates are associated with postoperative complications. Recently, a technique emerged whereby preoperative patient-specific reconstructive plates (PSRP) are developed in the hopes of eliminating errors in the plate-bending process. This study's objective is to determine if reconstructions performed with PSRP are more accurate than manually contoured plates. Ten Otolaryngology residents each performed two ex vivo mandibular reconstructions, first using a PSRP followed by a manually contoured plate. Reconstruction time, CT scans, and accuracy measurements were collected. Paired Student's t-test was performed. There was a significant difference between reconstructions with PSRP and manually contoured plates in: plate-mandible distance (0.39 ± 0.21 vs. 0.75 ± 0.31 mm, p = 0.0128), inter-fibular segment gap (0.90 ± 0.32 vs. 2.24 ± 1.03 mm, p = 0.0095), mandible-fibula gap (1.02 ± 0.39 vs. 2.87 ± 2.38 mm, p = 0.0260), average reconstruction deviation (1.11 ± 0.32 vs. 1.67 ± 0.47 mm, p = 0.0228), mandibular angle width difference (5.13 ± 4.32 vs. 11.79 ± 4.27 mm, p = 0.0221), and reconstruction time (16.67 ± 4.18 vs. 33.78 ± 8.45 min, p = 0.0006). Lower plate-mandible distance has been demonstrated to correlate with decreased plate extrusion rates. Similarly, improved bony apposition promotes bony union. PSRP appears to provide a more accurate scaffold to guide the surgeons in assembling donor bone segments, which could potentially improve patient outcome and reduce surgical time. Additionally, in-house PSRP can serve as a low-cost surgical simulation tool for resident education.

Azole-resistant Aspergillus fumigatus is highly prevalent in the environment of Vietnam, with marked variability by land use type.

Azole-resistant environmental Aspergillus fumigatus presents a threat to public health but the extent of this threat in Southeast Asia is poorly described. We conducted environmental surveillance in the Mekong Delta region of Vietnam, collecting air and ground samples across key land-use types, and determined antifungal susceptibilities of Aspergillus section Fumigati (ASF) isolates and azole concentrations in soils. Of 119 ASF isolates, 55% were resistant (or non-wild type) to itraconazole, 65% to posaconazole and 50% to voriconazole. Azole resistance was more frequent in A. fumigatus sensu stricto isolates (95%) than other ASF species (32%). Resistant isolates and agricultural azole residues were overrepresented in samples from cultivated land. cyp51A gene sequence analysis showed 38/56 resistant A. fumigatus sensu stricto isolates carried known resistance mutations, with TR34 /L98H most frequent (34/38).

Maxillectomy defects: Virtually comparing fibular and scapular free flap reconstructions.

BACKGROUND: This study virtually compares patient-specific fibular and scapular reconstructions for maxillectomies. METHODS: Nine maxillectomy defects were created on 10 maxillas and virtually reconstructed with patient-specific fibulas and scapulas. Reconstructions were compared for restoring midface cephalometrics, dental implantability, and pedicle length. RESULTS: Of 90 maxillectomy defects, the vertically oriented scapula provided improved orbital floor and maxillary height reconstructions (p < 0.001), albeit at the cost of dental implantability compared to the fibula (p < 0.001). In two defects crossing the midline, the fibula, allowing for more osteotomies, provided improved maxillary projection. In the remaining three defects crossing the midline, the horizontally oriented scapula was comparable to the fibula. Fibular and scapular reconstructions were amenable for dental implantation and had similar pedicle lengths, although favoring scapula in extensive defects. CONCLUSION: Fibular and scapular reconstructions of maxillectomy defects provide unique strengths. This virtual analysis can guide a goal-oriented reconstruction based on defect type and patient-specific goals.

Predicting the Premorbid Shape of a Diseased Mandible.

OBJECTIVES/HYPOTHESIS: Virtual surgical planning (VSP) for reconstructions of advanced mandibular neoplasms that have distorted the contour of the mandible is challenging, as the premorbid shape of the mandible is unknown. We introduce a novel modeling technique, based on a statistical shape model (SSM), that has learned the shape of a normal mandible from a set of 84 mandibles, such that given a diseased mandible, the model can determine its premorbid shape. METHODS: Eighty-four control mandibles were used to generate an SSM. Various mandibular defects were created, and the SSM was applied to predict the shape of the original mandible. The predicted and original shape of the defect were compared for accuracy using volumetric overlap and Hausdorff distance. All mandibular VSP cases in the past 2 years were reviewed to identify those that required virtual preprocessing due to significantly distorted mandibular contours. The SSM was compared to those cases requiring preprocessing and highlighted in one prospective VSP. RESULTS: The average volumetric overlap and Hausdorff distance between the defect replacement and the defect are 73.9% ± 13.3% and 4.51 mm ± 2.65 mm, respectively. The SSM is more accurate for smaller defects, and those not including the condyle. Ten out of 40 VSP cases required preprocessing using four different techniques. Qualitatively, the SSM outperformed those preprocessing techniques applied in the retrospective cases. CONCLUSIONS: The SSM can accurately predict the premorbid shape of a distorted mandible and is superior to current preprocessing techniques. The SSM was successfully applied to a retrospective series and one prospective index case. LEVEL OF EVIDENCE: 4 Laryngoscope, 131:E781-E786, 2021.