Improving the Accuracy of Maxillary Sinus Balloon Dilation Using Virtual Reality Navigation: A Proof-of-Concept Study.

BACKGROUND: The ability to reliably and accurately cannulate the natural ostium of the maxillary sinus during balloon sinus dilation (BSD) has been criticized. Conventional computed tomography (CT)-guided navigation systems are helpful when dilating other sinuses, but they fail to provide meaningful feedback to guide accurate dilation of the maxillary sinus. OBJECTIVE: This study explores the potential impact of a new navigation system with virtual reality (VR) functionality on successful BSD of the maxillary sinus. METHODS: Using the established methodology, a cadaveric evaluation of the accuracy of maxillary BSD with a VR-equipped navigation system and balloon was undertaken. The natural ostium was landmarked on CT images with a beacon, and a VR intrasinus camera view was used to guide balloon dilation by a team of 2 rhinologists. Following the procedure, uncinectomies were performed to directly assess the accuracy of dilation. Standardized video clips with a 30° endoscopic view of the area were reviewed by 3 blinded rhinologists from different institutions who were not part of the procedures. Dilation of the natural ostium was scored as "successful," "unsuccessful," or "unsure." RESULTS: Sixteen maxillary BSDs were completed in 8 cadavers using VR navigation. The medial wall of the maxillary sinus showing the natural ostium as well as any accessory ostia were readily visualized and labeled with a beacon in all cases using the 3D virtual rendering feature. Dilations were scored using a standardized rubric. Any "unsure" responses from the reviewers were categorized as "unsuccessful" for analysis purposes. The accuracy rate for dilation of the maxillary sinus natural ostium was 77%. Despite the use of cadaveric tissues, a fair interrater agreement (kappa 0.21) was achieved. CONCLUSION: Using VR navigation appears to improve the accuracy of cannulating the natural ostium during maxillary BSD, which could lead to better outcomes. Further study in live subjects is warranted.

Free Tissue Transfer for Skull Base Osteoradionecrosis: A Novel Approach in the Endoscopic Era.

OBJECTIVES: Osteoradionecrosis (ORN) of the skull base and craniovertebral junction is a challenging complication of radiation therapy (RT). Severe cases often require surgical intervention through a multi-modal approach. With the evolution in endoscopic surgery and advances in skull base reconstruction, there is an increasing role for microvascular free tissue transfer (MFTT). We describe an endoscopic-assisted approach for the management of ORN of the skull base using fascia lata for MFTT. STUDY DESIGN: Retrospective case series. METHODS: Between 2017 and 2021, a review of all cases in which fascia lata MFTT was utilized for skull base ORN was performed. Patient demographics, preoperative characteristics, and postoperative outcomes with long-term follow-up were reviewed. RESULTS: Five patients were identified. Mean duration to onset of ORN was 17 months following RT. A trial of antibiotics, hyperbaric oxygen (HBO), and/or limited debridement was attempted without success. Refractory pain and progressive osteomyelitis were unifying symptoms. All patients underwent endoscopic debridement of the affected region of ORN prior to MFTT. Vascularized fascia lata was inset through a combined endonasal and transoral corridor. There was improvement in chronic pain in the postop setting with no patients requiring continued antibiotics or HBO therapy. Mean post-op follow-up was 23 months. CONCLUSIONS: With continued evolution in endoscopic, minimally invasive approaches, there is an expanding indication for early surgical management in refractory ORN. Fascia lata MFTT is a novel and effective strategy for the management of ORN of the skull base and upper cervical spine with excellent postoperative outcomes and limited patient morbidity. LEVEL OF EVIDENCE: 4 Laryngoscope, 133:562-568, 2023.

Phenotypes of Allergic Asthma: Does In-Vitro Allergy Testing Help Predict Asthma Disease Severity?

BACKGROUND: Allergy and asthma are often diagnosed concomitantly. Patients with both diagnoses might need to have a more targeted approach to reduce the symptomatic burden and severity of disease. OBJECTIVE: This study was designed to explore the relationship between specific allergen sensitization, and asthma diagnosis and severity with the hypothesis that patients who tested positive to a higher allergy class of response and to more allergens would be more likely to have severe asthma. METHODS: A retrospective review was performed on 1419 charts that had a positive IgE allergy class blood test between 2014 and 2018. A total of 701 patients had one or more positive tests and a diagnosis of asthma. Patient demographics and pertinent variables including all clinic and ED visits, specific allergy and class of response, and information related to their asthma treatment and severity were recorded. Logistic regression was used to analyze the likelihood of asthma diagnosis, concomitant diagnosis of asthma and allergic rhinitis, and measures of asthma severity. RESULTS: Higher class of response to cat dander 1.24 (1.09, 1.41), dog dander 1.29 (1.13, 1.47), lamb's quarter 1.35 (1.06, 1.70), house dust 1.41 (1.11, 1.82), Cladosporium herbarum 1.35 (1.07, 1.67) or cockroach 1.56 (1.00, 2.44) showed increased odds of hospitalizations. There was a statistically significant difference between the average number of classes for patients with and without asthma (P < .001), and those with and without steroids (P < .001). CONCLUSIONS: This study found that positivity to cat dander, dog dander, some fungus, and house dust was associated with more severe asthma.

Systematic review of olfactory outcomes after nasoseptal flap harvest for endoscopic skull base surgery: Does using cold steel or olfactory strip preservation matter?

BACKGROUND: Several studies have described techniques aimed at mitigating olfactory dysfunction after nasoseptal flap (NSF) harvest for endoscopic skull base surgery (ESBS). No consensus exists as to whether popular methods including using cold steel (CS) versus electrocautery (EC) or septal olfactory strip (SOS) preservation offer an advantage. This systematic review was performed to examine the impact of these two technical variations of NSF harvest on postoperative olfactory outcomes. METHODS: Following PRISMA guidelines, PubMed, Scopus, and Web of Science were searched for articles reporting olfactory outcomes in ESBS cases employing an NSF. Original articles focusing on technique variations of the NSF and reporting at least one objective olfactory measure were included. RESULTS: Nine studies comprising 610 patients were included. Various, olfactory testing outcomes were reported, and postoperative follow-up ranged from 6 weeks to 12 months. Three studies, including a randomized controlled trial, compared the use of CS and EC for the superior incision of the NSF. No significant difference was found in objective olfactory function (p > 0.05) when comparing these techniques. Five studies comprising 504 patients reported results from SOS-sparing. SOS-sparing technique in NSF harvest demonstrated smell preservation in the postoperative setting when compared with preoperative measures (p > 0.05); however, no direct comparison to non-SOS-sparing techniques was made. CONCLUSION: The use of CS as opposed to EC for the superior NSF incision does not appear to confer an advantage in preserving postoperative olfactory function (grade B evidence). SOS preservation may be associated with better olfactory outcomes in NSF harvest (grade C evidence).

Using the Middle Turbinate to Protect the Skull Base in Endoscopic Transsphenoidal Surgery: A Cadaver Study.

OBJECTIVES: Inadvertent intracranial injury from nasogastric tube (NGT) placement is a described and potentially fatal complication following endoscopic transsphenoidal hypophysectomy (TSH). This cadaver study assessed the role of middle turbinate (MT) preservation and medialization in preventing accidental skull base injury from NGT insertion after TSH. Methods: Standard approach for TSH was performed on 3 human cadavers. MTs were placed into neutral position (MTN), then medialized via suture pexy to the septum (MTP), and subsequently resected (MTR). After each stage, 3 blinded individuals passed a 10 F Dobhoff and a 16 F NGT on each side of each cadaver (5 passes per side). Using endoscopic visualization, each pass was scored by a blinded reviewer based on the first contact point of the tube (0 = nasopharynx, 1 = inferior sphenoid face, 2 = sphenoid sinus), with higher scores suggestive of increased risk of intracranial injury. Results: There were 270 Dobhoff and 270 NGT passes scored. Data was divided into 3 groups based on presence and position of the MT. Significant differences were demonstrated between all three groups [one-way ANOVA: Dobhoff F(2,267) = 6.981, p = 0.001], [NGT F(2,267) = 17.582, p < 0.001]. There were significant differences between means for MTN versus MTP groups [Dobhoff (0.43 vs 0.22, p = 0.007), NGT (0.73 vs 0.28, p < 0.001)] and MTP versus MTR groups [Dobhoff (0.22 vs 0.55, p < 0.001), NGT (0.28 vs 0.81, p < 0.001)], indicating that the presence and position of the MT can significantly affect the accessibility of the sphenoid sinus interior after TSH. There was a trend toward lower means in the MTN group compared to the MTR group. Conclusion: MT preservation and deliberate medialization against the septum may reduce risk of inadvertent intracranial NGT injury in postop TSH patients. This simple maneuver should be considered in all routine TSH procedures.

Prevalence of Tibial Artery and Pedal Arch Patency by Angiography in Patients With Critical Limb Ischemia and Noncompressible Ankle Brachial Index.

BACKGROUND: Approximately 20% of patients undergoing ankle brachial index testing for critical limb ischemia have noncompressible vessels because of tibial artery calcification. This represents a clinical challenge in determining tibial artery patency. We sought to identify the prevalence of tibial artery and pedal arch patency by angiography in these patients. METHODS AND RESULTS: One hundred twenty-five limbs (of 89 patients) with critical limb ischemia and ankle brachial index ≥1.4 who underwent lower extremity angiograms within 1 year were included. Reviewers of angiography were blinded to results of physiological testing. Tibial artery vessels were classified as completely occluded, significantly stenosed (≥50%), or patent (<50% stenosis). The sensitivity of toe brachial index and pulse volume recording to predict tibial artery disease was also determined. Of 125 limbs with noncompressible ankle brachial index, 72 (57.6%) anterior tibial and 80 (64%) posterior tibial arteries were occluded. Another 23 (18.4%) anterior tibial and 13 (10.4%) posterior tibial arteries had ≥50% stenosis. Pulse volume recording was moderate to severely dampened in 54 of 119 (45.4%) limbs. Toe brachial index <0.7 was found in 75 of 83 (90.4%) limbs. Moderate to severe pulse volume recording dampening was 43.6% sensitive, whereas toe brachial index <0.7 was 89.7% sensitive in diagnosing occluded or significantly stenotic tibial artery disease. The pedal arch was absent or incomplete in 86 of 103 (83.5%) limbs. CONCLUSIONS: Among patients with critical limb ischemia and noncompressible ankle brachial index results, the prevalence of occlusive tibial and pedal arch disease is very high. Toe brachial index <0.7 is more sensitive in diagnosing occluded and significantly stenotic tibial artery disease in these patients compared with ankle pulse volume recording.

Antibiotic-releasing microspheres prevent mesh infection in vivo.

BACKGROUND: Infection remains a dreaded complication after implantation of surgical prosthetics, particularly after hernia repair with synthetic mesh. We previously demonstrated the ability of a newly developed polymer to provide controlled release of an antibiotic in a linear fashion over 45 d. We subsequently showed that coating mesh with the drug-releasing polymer prevented a Staphylococcus aureus (SA) infection in vivo. To broaden the applicability of this technology, the polymer was synthesized as isolated "microspheres" and loaded with vancomycin (VM) before conducting a noninferiority analysis. MATERIALS AND METHODS: Seventy-three mice underwent creation of a dorsal subcutaneous pocket that was inoculated with 104 colony forming units (CFU) of green fluorescent protein (GFP)-labeled SA (105 CFU/mL). Multifilament polyester mesh (7 × 7 mm) was placed into the pocket, and the skin was closed. Mesh was either placed alone (n = 16), coated with VM-loaded polymer (n = 20), placed next to VM-loaded microspheres (n = 20) or unloaded microspheres (n = 10), or flushed with VM solution (n = 7). Quantitative tissue/mesh cultures were performed at 2 and 4 week. Mice with open wounds and explanted mesh were excluded. RESULTS: Twenty-two of 23 (96%) tissue-mesh samples from mesh alone or empty miscrospheres were positive for GFP-labeled SA at 2 and 4 wk. Six of seven (86%) samples from the VM flush group were positive for GFP SA at 4 wk. Thirty-eight of 38 (100%) VM-loaded crosslinked cyclodextrin polymers-coated mesh or VM-loaded microspheres were negative for GFP SA at 2 and 4 wk. CONCLUSIONS: Slow affinity-based drug-releasing polymers in the form of microspheres are able to adequately clear a bacterial burden of SA and prevent mesh infection.

A Multidisciplinary Approach to Medical Weight Loss Prior to Complex Abdominal Wall Reconstruction: Is it Feasible?

Obesity is a major risk factor for perioperative morbidity, especially for patients undergoing complex incisional hernia repair. The feasibility and effectiveness of medical weight loss programs prior to complex abdominal wall reconstruction have not been well characterized. Here, we report our experience collaborating with a medical weight loss specialist utilizing a protein sparing modified fast in order to optimize weight loss prior to complex abdominal wall reconstruction. Morbidly obese patients (body mass index (BMI) > 35 kg/m(2)) evaluated by our medical weight loss specialist prior to complex ventral hernia repair were identified within our prospective database. Our primary outcome measure was the amount of weight lost prior to surgical intervention. Our secondary outcome measure was to determine the maintenance of weight loss during long-term follow-up after the surgical intervention. A total of 25 patients with a BMI > 35 kg/m(2) were evaluated by our medical weight loss specialist prior to undergoing a planned incisional hernia repair. The mean weight of the patients preoperatively was 128 kg ± 25 (range 96-205 kg) (mean ± standard deviation), and the mean BMI was 49 kg/m(2) ± 10 (range 36-85). After completion of the preoperative modified protein sparing fast, the mean preoperative weight loss of the group was 24 kg ± 21 (range 2-80 kg). The overall change in BMI for the group prior to surgery was 9 kg/m(2) ± 8 (0.6 to 33). The percentage of excess BMI loss and total BMI loss preoperatively was 37 % ± 23 (2 to 83) and 18 % ± 12 (1 to 43), respectively. Of the 24 patients that initially lost weight in the program preoperatively, 22 (88 %) successfully maintained their weight loss for the entire study period for an average of 18 months. Collaboration with a medical weight loss specialist and a surgeon with a structured approach using a modified protein sparing fast can successfully result in meaningful weight loss prior to complex abdominal wall reconstruction. The majority of patients in this study were able to maintain their weight loss during long-term follow-up. Utilization of a protein sparing modified fast in collaboration with a medical weight loss specialist is a valuable resource for guiding weight loss in patients with morbid obesity prior to elective complex surgical procedures.