A fusion of VGG-16 and ViT models for improving bone tumor classification in computed tomography.

Background and Objective: Bone tumors present significant challenges in orthopedic medicine due to variations in clinical treatment approaches for different tumor types, which includes benign, malignant, and intermediate cases. Convolutional Neural Networks (CNNs) have emerged as prominent models for tumor classification. However, their limited perception ability hinders the acquisition of global structural information, potentially affecting classification accuracy. To address this limitation, we propose an optimized deep learning algorithm for precise classification of diverse bone tumors. Materials and Methods: Our dataset comprises 786 computed tomography (CT) images of bone tumors, featuring sections from two distinct bone species, namely the tibia and femur. Sourced from The Second Affiliated Hospital of Fujian Medical University, the dataset was meticulously preprocessed with noise reduction techniques. We introduce a novel fusion model, VGG16-ViT, leveraging the advantages of the VGG-16 network and the Vision Transformer (ViT) model. Specifically, we select 27 features from the third layer of VGG-16 and input them into the Vision Transformer encoder for comprehensive training. Furthermore, we evaluate the impact of secondary migration using CT images from Xiangya Hospital for validation. Results: The proposed fusion model demonstrates notable improvements in classification performance. It effectively reduces the training time while achieving an impressive classification accuracy rate of 97.6%, marking a significant enhancement of 8% in sensitivity and specificity optimization. Furthermore, the investigation into secondary migration's effects on experimental outcomes across the three models reveals its potential to enhance system performance. Conclusion: Our novel VGG-16 and Vision Transformer joint network exhibits robust classification performance on bone tumor datasets. The integration of these models enables precise and efficient classification, accommodating the diverse characteristics of different bone tumor types. This advancement holds great significance for the early detection and prognosis of bone tumor patients in the future.

Cartilage on the floor: how effective is antibiotic sterilization?

OBJECTIVE: To determine the incidence of positive cultures from contaminated nasal cartilage and to demonstrate the effectiveness of antibiotic irrigation as a means of sterilization. DESIGN: A prospective study. SETTING: Tertiary referral centre. METHODS: Nasal septal cartilage was harvested during routine endoscopic septoplasties. The harvested cartilage was then dropped on the floor for 60 seconds. The cartilage was then divided into four equal portions, which were then divided into four experimental groups: (1) untreated, (2) normal saline soak for 60 seconds, (3) 40 mg/mL gentamicin solution soak for 60 seconds, and (4) 300 seconds. All specimens were sent for bacterial culture and sensitivity, along with nasal swabs and floor swabs. The incidence of bacterial contamination in the different groups was analyzed using the McNemar hypothesis. MAIN OUTCOME MEASURES: Correlation between bacterial culture results and treatments of contaminated nasal septal cartilages. RESULTS: Thirty-two patients were enrolled in this study. Thirty-one percent of the untreated specimens had bacterial contamination. Thirty-one percent of the saline-soaked specimens had significant bacterial growth. Bacterial growth was not observed in any of the specimens treated with gentamicin irrigation for 60 seconds (absolute reduction of 31%); one specimen (3%) in the 300 seconds gentamicin group had a positive culture. A correlation of 70% was observed in the bacterial growth observed in the swab of the operating room floor and the untreated cartilage. CONCLUSIONS: When no other options are available, this study demonstrates that cartilage dropped on the floor can be decontaminated by washing with gentamicin.

Cost-effectiveness of simultaneous versus sequential surgery in head and neck reconstruction.

OBJECTIVE: To determine whether simultaneous (ablation and reconstruction overlaps by two teams) head and neck reconstruction is cost effective compared to sequentially (ablation followed by reconstruction) performed surgery. STUDY DESIGN: Case-controlled study. SETTING: Tertiary care hospital. SUBJECTS: Oncology patients undergoing free flap reconstruction of the head and neck. METHODS: A match paired comparison study was performed with a retrospective chart review examining the total time of surgery for sequential and simultaneous surgery. Nine patients were selected for both the sequential and simultaneous groups. Sequential head and neck reconstruction patients were pair matched with patients who had undergone similar oncologic ablative or reconstructive procedures performed in a simultaneous fashion. A detailed cost analysis using the microcosting method was then undertaken looking at the direct costs of the surgeons, anesthesiologist, operating room, and nursing. RESULTS: On average, simultaneous surgery required 3 hours 15 minutes less operating time, leading to a cost savings of approximately $1200/case when compared to sequential surgery. This represents approximately a 15% reduction in the cost of the entire operation. CONCLUSION: Simultaneous head and neck reconstruction is more cost effective when compared to sequential surgery.

Microvascular reconstruction in the vessel-depleted neck.

PURPOSE OF REVIEW: Microvascular reconstruction for head and neck cancers has improved both cosmesis and functionality of patients undergoing treatment. Many patients have had prior surgery (neck dissection), radiation and/or chemotherapy as part of their management. When microvascular reconstruction is required after previous treatment, finding appropriate vessels for anastomosis can be difficult. In this paper we explore the options for microvascular reconstruction in the vessel-depleted neck. RECENT FINDINGS: Arterial options that exist when the neck is depleted of vessels include the superficial temporal, transverse cervical, thoracoacromial, and the internal mammary artery. Venous options include the cephalic vein and vein grafts. SUMMARY: The external carotid artery and the internal jugular vein are the most commonly utilized vessels in microvascular reconstruction when available. However, prior chemotherapy and/or radiation can cause significant scarring and damage to these vessels. Also in patients who have had previous surgery, these vessels can be resected or altered in a way that they are deemed unusable. In these situations several vascular options exist outside the neck.

Septoplasty retards midfacial growth in a rabbit model.

OBJECTIVES/HYPOTHESIS: Septoplasty in the prepubertal age group is a controversial operation because of concerns regarding retardation of subsequent midfacial growth. This study uses a validated rabbit snout model to determine if septoplasty results in midfacial growth retardation, and if the retardation can be averted by replacing resected cartilage with a porous polyethylene implant. STUDY DESIGN: Prospective controlled animal study. METHODS: Sixteen 9-week-old New Zealand white rabbits were divided into four groups: two control and two experimental. The experimental groups both underwent conservative submucoperichondrial surgical excision of a portion of their septum, leaving a generous dorsal and caudal septal strut for nasal support similar to what would be done clinically in humans. One of the experimental groups had replacement of the resected area by a rigid porous polyethylene graft, and in the other experimental group the resected area was left empty. Cephalometric measurements were performed on radiographs taken at the time of implantation, and at sacrifice when the rabbits were mature at 24 weeks of age. RESULTS: There were significant disturbances in snout growth between experimental and control groups, and no significant differences between the two experimental groups or between the two control groups. CONCLUSIONS: These data demonstrate midfacial growth retardation after conservative septoplasty in young rabbits, and that this retardation could not be averted by replacing the resected cartilage with a porous polyethylene graft. These data are in agreement with human studies.

Laryngeal candidiasis in the outpatient setting.

OBJECTIVES: We present the largest case series on laryngeal candidiasis and review the literature on the diagnosis and management of laryngeal candidiasis. SUBJECTS AND METHODS: Fifty-four patients were included in a retrospective chart review of all cases seen at the Pacific Voice Clinic, University of British Columbia, Vancouver, from 1995 to 2005. RESULTS: The most common presenting symptom was dysphonia (37 patients; 69%). Forty-eight patients (89%) were on steroid inhalers, and four patients (7%) were on oral prednisone. In terms of anatomic involvement, 18 patients (33%) showed Candida involvement in all three anatomic locations: the hypopharynx, the supraglottis, and the glottis. In 15 patients (28%), the Candida was isolated to the glottis. The remaining patients showed subglottic and glottic involvement. Fifty-two patients (96%) were successfully treated with a single course of an oral antifungal. CONCLUSION: The most common risk factor identified was inhaled steroids. Most often, laryngeal candidiasis is effectively treated with oral antifungal medications.

Transforming growth factor-beta1 shows an incremental osteoinductive dose-response relationship.

OBJECTIVE: To determine if there is a dose-response curve for TGF-beta1 in a rabbit calvarial defect model. STUDY DESIGN: Controlled animal study using arms of increasing concentrations of TGF-beta1 to evaluate the osteoinductive potential of each arm. METHODS: Sixteen skeletally mature New Zealand white rabbits were randomized into control and experimental arms. Incremental doses of TGF-beta1 delivered in an inactivated guanidine-extracted demineralized bone matrix (Gu-DBM) carrier were implanted into a critically sized calvarial defect. The animals were sacrificed at 4 weeks and histomorphometric analysis was then accomplished. RESULTS: TGF-beta1 showed a dose-response relationship, with the higher doses chosen for this study causing more robust osteoinduction. CONCLUSIONS: In this pilot dosing study, TGF-beta1 demonstrates increasing osteoinduction with increasing dose levels in this animal model.

Patients' perceptions and experiences of family medicine residents in the office.

OBJECTIVE: To examine patients' perceptions and experiences of having family medicine residents in the office. DESIGN: Descriptive survey; questionnaire completed by patients. SETTING: Outpatient office of 4 family physicians in the greater Vancouver area, affiliated with the Department of Family Medicine at the University of British Columbia. PARTICIPANTS: A total of 265 English-speaking adult patients attending the office. MAIN OUTCOME MEASURES: Patients' self-reported perceptions and experiences of having family medicine residents in the office. RESULTS: Response rate was 94.7% (251 of 265 patients completed the questionnaire). Although 81% of respondents had seen residents in the office, 59% did not understand a resident's training or thought residents were medical students. The 3 main reasons participants gave for choosing to have residents involved in their care were the following: to contribute to training future doctors (61.8%); to obtain 2 opinions instead of 1 (20%); and residents are most up-to-date (11.2%). The most common reasons for choosing not to see residents were the following: to continue relationships with their own doctors (54.2%); to avoid the need to repeat history (18.6%); and the perception that residents are less experienced (16.9%). Having a resident involved in their care was perceived as a positive experience by 95.5% of respondents who had seen residents. Overall satisfaction with care and overall comfort in dealing with residents were ranked good to excellent by 91.8% and 90.8% of respondents, respectively. About 71% of patients said they would choose to have residents involved in their care. CONCLUSION: Respondents reported very positive experiences with having family medicine residents in the office. Overall comfort and satisfaction with seeing family medicine residents was reported to be extremely high, and most patients surveyed would choose to have family medicine residents involved in their care. Patients needed to know more about the resident's level of training and the role of residents in patient-resident interactions.

Role of Tonsillectomy in PFAPA Syndrome.

OBJECTIVE: To examine the efficacy of tonsillectomy in ameliorating symptoms and preventing recurrence of episodes in children with PFAPA syndrome (periodic fever, aphthous stomatitis, pharyngitis, and adenitis). DESIGN: Retrospective case series. SETTING: Tertiary care children's hospital. PATIENTS: Patients who presented to a major tertiary teaching hospital in Vancouver, British Columbia, Canada, between 2000 and 2004 with the diagnosis of PFAPA syndrome or for whom the diagnosis was made on their initial consultation. INTERVENTION: Tonsillectomy. MAIN OUTCOME MEASURES: Resolution of symptoms at 3, 12, and 24 months after tonsillectomy. RESULTS: Eight of the 9 patients achieved complete remission within 3 months. In the remaining patient, the frequency of episodes decreased from every 2 weeks to once every 3 to 4 months. This patient eventually had resolution of symptoms at 2 years after tonsillectomy. No complications resulted from the tonsillectomy. CONCLUSION: Tonsillectomy is a viable treatment option for patients with PFAPA syndrome.

Systemic absorption of topical gentamicin sinus irrigation.

OBJECTIVE: Evidence surrounding systemic absorption of gentamicin during intraoperative irrigation of the paranasal sinuses is lacking. The objectives of this study were to determine (1) if topical gentamicin is absorbed from the paranasal sinuses, (2) if hearing loss occurs following topical administration of gentamicin, and (3) if gentamicin placed within the sinuses travels retrograde (against mucociliary clearance) up the auditory tube to the middle ear. DESIGN: Consecutive, prospective case series. SETTING: Tertiary centre. METHODS: A series of patients undergoing sinus surgery were identified. Fluorescein-stained gentamicin was used to irrigate the sinus cavities intraoperatively. Otoscopy using a filtered light source was performed 30 minutes postoperatively. MAIN OUTCOME MEASURES: (1) Serum gentamicin levels preirrigation and at 30 minutes postirrigation and (2) change in pure-tone average and threshold at 8 kHz pre- and postoperative audiograms. RESULTS: Twenty patients were enrolled. Serum gentamicin levels were detectable in three patients. Fluorescein irrigation solution was not visualized in the middle ear space. No significant hearing loss was observed in any of the patients. CONCLUSIONS: Gentamicin may be absorbed from the nasal mucosa during intraoperative irrigation of the sinuses. However, detectable serum levels were well below therapeutic levels. The clinical significance of this finding requires further study to determine if topical sinus irrigation with gentamicin is a safe procedure.

Return to home, school, and sports after electrosurgical adenoidectomy: when is it safe?

OBJECTIVE: To determine when it is safe for healthy children to return to home, school, and sports after uncomplicated electrosurgical adenoidectomy (EA). DESIGN: (1) A survey of Canadian otolaryngologists (COs) regarding their EA complication rates and their opinions regarding best practice standards for patient care after EA. (2) Informal retrospective analysis of approximately 200 children who have been allowed to resume sports 3 days after uncomplicated EA. RESULTS: (1) Thirteen COs responded to the survey. The total estimated EA cases performed were 8617 over 10 years. Four patients were known to have bled mildly; none required reoperation. Eleven of 13 COs supported discharge home 2 hours after uncomplicated EA if other standard discharge criteria were met. Seven of 13 COs supported a return to school the next day if the child had returned to his or her usual state of health; however, 2 COs suggested 7 to 10 days at home. Four of 13 COs supported a return to sports 3 days after uncomplicated EA. (2) None of the 200 children who had been allowed to resume sports 3 days after uncomplicated EA have had any known bleeding. At least 10 toddlers have actually engaged in unplanned strenuous exercise within 4 to 6 hours of EA without adverse effect. CONCLUSIONS: Considerable variation exists in Canada in terms of current practice standards regarding return to home, school, and sports after uncomplicated EA. Survey data suggest that, after uncomplicated EA, it is safe for healthy children to return home after 2 hours and to school the next day. Preliminary data suggest that it may be safe for children to resume sports 3 days after uncomplicated EA; however, ideally, this should be studied prospectively, on a large scale.

Reovirus salvage of squamous cell cancer-contaminated wounds.

PURPOSE: To assess the susceptibility of human squamous cell carcinoma to reovirus infection in vitro and in vivo using a murine model of cancer-contaminated wounds. METHODS: The University of Michigan squamous carcinoma 22B cell line was cultured and inoculated with reovirus in vitro. The effect of the reovirus was assessed with microscopy and a standard 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H tetrazolium bromide (MTT) assay. We used the previously established cancer-contaminated wound SCID mouse model to test saline and reovirus irrigation in vivo. Fifty-five mice were used; 15 were controls, 20 had immediate irrigation, and 20 had delayed irrigation. Surgical sites were assessed for palpable tumour biweekly. RESULTS: The microscopy and MTT assay both showed evidence of reovirus-mediated squamous cancer cell lysis. The control mice grew palpable tumours in 80% of the wounds. Immediate irrigation with saline delayed the onset of palpable tumour and demonstrated a persistent reduction in the rate of development of palpable tumours (p = .004 compared with controls). This effect disappeared when the saline irrigation was delayed, resulting in a tumour development rate that was not significantly different from that of the control. Wounds that were irrigated with reovirus, both immediately and delayed, did not produce palpable tumour (p < .0005 when compared with controls). CONCLUSIONS: (1) The University of Michigan squamous cell carcinoma 22B cell line is susceptible to reovirus in vitro. (2) Immediate irrigation with saline resulted in a significant delay in clinically evident tumour growth and a reduction in the rate of tumour development in the SCID mouse model. (3) The reovirus irrigation resulted in a significant reduction of tumour development in both the immediate and delayed groups in the SCID mouse model. (4) The efficacy of the reovirus irrigation in the delayed group suggests that the major mechanism of action is through a selective and specific targeting of implanted cancer cells.

A novel intravesical therapy for superficial bladder cancer in an orthotopic model: oncolytic reovirus therapy.

PURPOSE: To our knowledge this is the first report of intravesical oncolytic reovirus for therapy of superficial bladder cancer in an orthotopic bladder tumor model. Superficial bladder carcinomas are often multifocal and have high recurrences after surgical resection. In 20% of cases intravesical immunotherapy fails to prevent recurrence and complications from bacillus Calmette-Guerin (BCG) are common. Human reovirus is an oncolytic virus that selectively destroys cancer cells with an activated Ras pathway. We examined the ability of this virus to kill bladder cancer cells in vitro and inhibit tumor growth in vivo. MATERIALS AND METHODS: Following cytotoxicity assays in vitro dose escalation of intravesical reovirus was tested for tumor control and toxicity in a rat model. Treatments were done twice weekly for 3 weeks. In parallel intravesical BCG was studied. Animals were monitored on a daily basis for health status and by routine urine cytology. Animals underwent necropsy at study end point and appropriate tissues were taken for histology. RESULTS: Side effects in reovirus groups were minor compared with BCG complications. Tumor response (animal survival) was 90% 100 days after tumor implantation in reovirus treated animals, whereas the highest survival in BCG treated groups was 50%. Animals treated with reovirus had significantly higher tumor-free survival than those treated with immunotherapy or normal saline (log rank test p = 0.0002 and 0.04, respectively). CONCLUSIONS: Intravesical reovirus is safe and effective in this animal model and it may have clinical applications for bladder cancer treatment.

Selective reovirus killing of bladder cancer in a co-culture spheroid model.

Up to 50% of the transitional cell carcinomas (TCC) express an activated EGF pathway involving MAP/MEK and RAF kinase thus providing a novel means to selectively eliminate transformed cells expressing such proteins. This EGF pathway expression phenotype was also confirmed in our MGH-U3 and room temperature-112 human TCC cell lines, which makes them a suitable model target for the reovirus oncolysis. We report here on an in vitro assay of co-culture spheroids using either human or rat TCC cells with their corresponding fibroblasts to examine the potential of viral selective lysis for TCC. Reovirus, a respiratory enteric orphan virus, which mammals are exposed to early in life, was used in this study. Selective killing of transformed versus normal cells was assayed by time-lapse photography, vital dye staining, immunohistochemistry, and MTT assay. In this in vitro bladder cancer model, reovirus selectively destroyed the transformed cells by lysis or induction of apoptosis. Based on these findings we have initiated an in vivo pre-clinical study on intravesical administration of reovirus in an animal model to further explore the effect of reovirus-mediated oncolysis of TCC.