Search results for: stenosis
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 69

Search results for: stenosis

9 Characteristics of Clinical and Diagnostic Aspects of Benign Diseases of Cervi̇x in Women

Authors: Gurbanova J., Majidova N., Ali-Zade S., Hasanova A., Mikailzade P.

Abstract:

Currently, the problem of oncogynecological diseases is widespread and remains relevant in terms of quantitative growth. It is known that due to the increase in the number of benign diseases of the cervix, the development of precancerous conditions occurs. Benign diseases of the cervix represent the most common gynecological problem, which are often precursors of malignant neoplasms, especially cervical cancer. According to statistics, benign diseases of the cervix cover 25-45% of all gynecological diseases. Among women's oncogynecological diseases, cervical cancer ranks second in the world after breast cancer and ranks first in the mortality rate among oncological diseases in economically underdeveloped countries. We performed a comprehensive clinical and laboratory examination of 130 women aged 18 to 73 with benign cervical diseases. 59 (38.5%) women of reproductive age, as well as 39 (30%) premenopausal and 41 (31.5%) menopausal patients, participated in the study. Detailed anamnesis was collected from all patients, objective and gynecological examination was performed, laboratory and instrumental examinations (USM, IPV DNA, smear microscopy, and PCR bacteriological examination of sexually transmitted infections), simple and extended colposcopy, liquid-based РАР-smear smear and РАР-classic smear examinations were conducted. As a result of the research, the following nosological forms were found in women with benign diseases of the cervix: non-specific vaginitis in 10 (7.7%) cases; ectopia, endocervicitis - 60(46.2%); cervical ectropion - 7(5.4%); cervical polyp - 9(6.9%); cervical leukoplakia - 15(11.5%); atrophic vaginitis - 7(5.4%); condyloma - 12(9.2%); cervical stenosis - 2(1.5%); endometriosis of the cervix - was noted in 8 (6.2%) cases (p<0.001), respectively. Characteristics of the menstrual cycle among the examined women: normal cycle in 97 (74.6%) cases; oligomenorrhea – 23 (17.7%); polymenorrhea – 4(3.1%); algomenorrhea – noted in 6 (4.6%) cases (p<0.001). Cytological examination showed that: the specificity of liquid-based cytology was 76.2%, and the traditional PAP test was set at 70.6%. The overall diagnostic value was calculated to be 86% in liquid-based cytology and 78.5% in conventional PAP tests. Treatment of women with benign diseases of the cervix was carried out by diathermocoagulation method and "FOTEK EA 141M" device. It should be noted that 6 months after the treatment, after treatment with the "FOTEK EA 141M" device, there was no relapse in any patient. Recurrence was found in 23.7% of patients after diathermoelectrocoagulation. Thus, it is clear from the above that the study of cervical pathologies, the determination of optimal examinations, and effective treatment methods is one of the urgent problems facing obstetrics and gynecology.

Keywords: cervical cancer, cytological examination, PAP-smear, non-specific vaginitis

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8 Evaluation of Human Amnion Hemocompatibility as a Substitute for Vessels

Authors: Ghasem Yazdanpanah, Mona Kakavand, Hassan Niknejad

Abstract:

Objectives: An important issue in tissue engineering (TE) is hemocompatibility. The current engineered vessels are seriously at risk of thrombus formation and stenosis. Amnion (AM) is the innermost layer of fetal membranes that consists of epithelial and mesenchymal sides. It has the advantages of low immunogenicity, anti-inflammatory and anti-bacterial properties as well as good mechanical properties. We recently introduced the amnion as a natural biomaterial for tissue engineering. In this study, we have evaluated hemocompatibility of amnion as potential biomaterial for tissue engineering. Materials and Methods: Amnions were derived from placentas of elective caesarean deliveries which were in the gestational ages 36 to 38 weeks. Extracted amnions were washed by cold PBS to remove blood remnants. Blood samples were obtained from healthy adult volunteers who had not previously taken anti-coagulants. The blood samples were maintained in sterile tubes containing sodium citrate. Plasma or platelet rich plasma (PRP) were collected by blood sample centrifuging at 600 g for 10 min. Hemocompatibility of the AM samples (n=7) were evaluated by measuring of activated partial thromboplastin time (aPTT), prothrombin time (PT), hemolysis, and platelet aggregation tests. P-selectin was also assessed by ELISA. Both epithelial and mesenchymal sides of amnion were evaluated. Glass slide and expanded polytetrafluoroethylene (ePTFE) samples were defined as control. Results: In comparison with glass as control (13.3 ± 0.7 s), prothrombin time was increased significantly while each side of amnion was in contact with plasma (p<0.05). There was no significant difference in PT between epithelial and mesenchymal surfaces (17.4 ± 0.7 s vs. 15.8 ± 0.7 s, respectively). However, aPPT was not significantly changed after incubation of plasma with amnion epithelial and mesenchymal surfaces or glass (28.61 ± 1.39 s, 31.4 ± 2.66 s, glass, 30.76 ± 2.53 s, respectively, p>0.05). Amnion surfaces, ePTFE and glass samples have less hemolysis induction than water considerably (p<0.001), in which no differences were detected. Platelet aggregation measurements showed that platelets were less stimulated by the amnion epithelial and mesenchymal sides, in comparison with ePTFE and glass. In addition, reduction in amount of p-selectin, as platelet activation factor, after incubation of samples with PRP indicated that amnion has less stimulatory effects on platelets than ePTFE and glass. Conclusion: Amnion as a natural biomaterial has the potential to be used in tissue engineering. Our results suggest that amnion has appropriate hemocompatibility to be employed as a vascular substitute.

Keywords: amnion, hemocompatibility, tissue engineering, biomaterial

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7 Computational Simulations and Assessment of the Application of Non-Circular TAVI Devices

Authors: Jonathon Bailey, Neil Bressloff, Nick Curzen

Abstract:

Transcatheter Aortic Valve Implantation (TAVI) devices are stent-like frames with prosthetic leaflets on the inside, which are percutaneously implanted. The device in a crimped state is fed through the arteries to the aortic root, where the device frame is opened through either self-expansion or balloon expansion, which reveals the prosthetic valve within. The frequency at which TAVI is being used to treat aortic stenosis is rapidly increasing. In time, TAVI is likely to become the favoured treatment over Surgical Valve Replacement (SVR). Mortality after TAVI has been associated with severe Paravalvular Aortic Regurgitation (PAR). PAR occurs when the frame of the TAVI device does not make an effective seal against the internal surface of the aortic root, allowing blood to flow backwards about the valve. PAR is common in patients and has been reported to some degree in as much as 76% of cases. Severe PAR (grade 3 or 4) has been reported in approximately 17% of TAVI patients resulting in post-procedural mortality increases from 6.7% to 16.5%. TAVI devices, like SVR devices, are circular in cross-section as the aortic root is often considered to be approximately circular in shape. In reality, however, the aortic root is often non-circular. The ascending aorta, aortic sino tubular junction, aortic annulus and left ventricular outflow tract have an average ellipticity ratio of 1.07, 1.09, 1.29, and 1.49 respectively. An elliptical aortic root does not severely affect SVR, as the leaflets are completely removed during the surgical procedure. However, an elliptical aortic root can inhibit the ability of the circular Balloon-Expandable (BE) TAVI devices to conform to the interior of the aortic root wall, which increases the risk of PAR. Self-Expanding (SE) TAVI devices are considered better at conforming to elliptical aortic roots, however the valve leaflets were not designed for elliptical function, furthermore the incidence of PAR is greater in SE devices than BE devices (19.8% vs. 12.2% respectively). If a patient’s aortic root is too severely elliptical, they will not be suitable for TAVI, narrowing the treatment options to SVR. It therefore follows that in order to increase the population who can undergo TAVI, and reduce the risk associated with TAVI, non-circular devices should be developed. Computational simulations were employed to further advance our understanding of non-circular TAVI devices. Radial stiffness of the TAVI devices in multiple directions, frame bending stiffness and resistance to balloon induced expansion are all computationally simulated. Finally, a simulation has been developed that demonstrates the expansion of TAVI devices into a non-circular patient specific aortic root model in order to assess the alterations in deployment dynamics, PAR and the stresses induced in the aortic root.

Keywords: tavi, tavr, fea, par, fem

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6 Congenital Malformations in Neonate Dogs in the Sao Paulo State University Veterinary Hospital, Botucatu, Sao Paulo, Brazil

Authors: Maria Lucia G. Lourenco, Keylla H. N. P. Pereira, Viviane Y. Hibaru, Fabiana F. Souza, Joao C. P. Ferreira, Simone B. Chiacchio, Luiz H. A. Machado

Abstract:

Congenital malformations are organ defects due to genetic or teratogenic causes, which can lead to high mortality in dog litters. This study assessed and described the congenital malformations in newborn dogs. The study included litters attend in the São Paulo State University (UNESP) Veterinary Hospital, Botucatu, Sao Paulo, Brazil. One hundred seventy-eight litters and 803 newborns were evaluated. The occurrence of litters with malformations was 24.7%, and of newborns was 6.7%. Twenty-seven different malformations were registered: anasarca, anal atresia, cleft lip, cleft palate, duplicated right ribcage, equinovarus, exencephaly, gastroschisis, hydrocephaly, lissencephaly, macroglossia, microphthalmia, mitral valve dysplasia, omphalocele, eyelid agenesis, persistent urachus, polydactyly, pulmonary hypoplasia, pulmonary valve stenosis, rectovaginal fistula, agenesis of abdominal muscles, rib hypoplasia, scoliosis, segmental aplasia of the intestines, tricuspid valve dysplasia, unilateral kidney agenesis, and vaginal atresia. 68.7% of newborns died as a result of malformations. The pure breeds with the highest chances of manifesting malformations in contrast with mixed breeds were French Bulldog, Pug, English Bulldog, Rottweiler, German Spitz, Pinscher, Pitbull, Yorkshire Terrier, and Shih-Tzu. Significant values (P<0.05) occurred in races French Bulldogs and Pugs. The causes of congenital disabilities are possibly related to hereditary genetic factors considering that the highest incidence of malformations was observed among purebreds. There as one case of exposure to a teratogenic agent, but no other mothers were exposed to such agents during pregnancy. Two cases of consanguineal breeding between siblings were reported. The mortality rate was high. Genetic breeding programs for reproduction, avoiding consanguineous mating, care in choosing parents, and avoiding maternal exposure to teratogenic agents are of utmost importance in reducing dog malformations and consequent mortality.

Keywords: congenital defects, teratogenesis, canine neonatology, newborn puppy

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5 Frequency of Surgical Complications in Diabetic Patients after Kidney Transplantation

Authors: Hakan Duger, Alparslan Ersoy, Canan Ersoy

Abstract:

The improvement of surgical techniques in recent years has reduced the frequency of postoperative complications in kidney transplant recipients. Novel immunosuppressive agents have reduced rates of graft loss due to acute rejection to less than 1%. However, surgical complications may still lead graft loss and morbidity in recipients. Because of potent immunosuppression, impaired wound healing and complications are frequent after transplantation. We compared the frequency of post-operative surgical complications in diabetic and non-diabetic patients after kidney transplantation. Materials and Methods: This retrospective study conducted in consecutive patients (213 females, 285 males, median age 39 years) who underwent kidney transplant surgery at our center between December 2005 and October 2015. The patients were divided into two groups: diabetics (46 ± 10 year, 26 males, 16 females) and non-diabetics (39 ± 12 year, 259 males, 197 females). Characteristics of both groups were obtained from medical records. Results: We performed 225 living and 273 deceased donor transplantations. Renal replacement type was hemodialysis in 60.8%, peritoneal dialysis in 17.3% and preemptive in 12%. The mean body mass indexes of the recipients were 24 ± 4.6 kg/m², donor age was 48.6 ± 14.3 years, cold ischemic time was 11.3 ± 6.1 hours, surgery time was 4.9 ± 1.2 hours, and recovery time was 54±31 min. The mean hospitalization duration was 19.1 ± 13.5 days. The frequency of postoperative surgical complications was 43.8%. There was no significant difference between the ratios of post-operative surgical complications in non-diabetic (43.5%) and diabetic (47.4%) groups (p=0.648). Post-operative surgical complications were lymphocele (24.6% vs. 23.7%), delayed wound healing (13.2% vs. 7.6%), hematoma (7.8% vs.15.8 %), urinary leak (4.6% vs. 5.3%), hemorrhage (5.1% vs. 0%), hydronephrosis (2.2% vs. 0%), renal artery thrombosis (1.5% vs. 0%), renal vein thrombosis (1% vs. 2.6%), urinoma (0.7% vs. 0%), urinary obstruction (0.5% vs. 0%), ureteral stenosis (0.5% vs. 0%) and ureteral reflux (0.2% vs. 0%) in non-diabetic and diabetic groups, respectively (p > 0.05). Mean serum creatinine levels in non-diabetics and diabetics were 1.43 ± 0.81 and 1.61 ± 0.96 mg/dL at 1st month (p=0.198). At the 6th month, the mean graft and patient survival times in patients with post-operative surgical complications were significantly lower than in those who did not (162.9 ± 3.4 vs. 175.6 ± 1.5 days, p=0.008, and 171 ± 2.9 vs. 176.1 ± 1.6 days, p=0.047, respectively). However, patient survival durations of non-diabetic (173 ± 27) and diabetic (177 ± 13 day) groups were comparable (p=0.396). Conclusion: As a result, we concluded that surgical complications such as lymphocele and delayed wound healing were common and that frequency of these complications in diabetic recipients did not differ from non-diabetic one. All persons involved in the postoperative care of kidney transplant recipients be aware of the potential surgical complications for rapid diagnosis and treatment.

Keywords: kidney transplantation, diabetes mellitus, surgery, complication

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4 Germline Mutations of Mitogen-Activated Protein Kinases Pathway Signaling Pathway Genes in Children

Authors: Nouha Bouayed Abdelmoula, Rim Louati, Nawel Abdellaoui, Balkiss Abdelmoula, Oldez Kaabi, Walid Smaoui, Samir Aloulou

Abstract:

Background and Aims: Cardiofaciocutaneous syndrome (CFC) is an autosomal dominant disorder with the vast majority of cases arising by a new mutation of BRAF, MEK1, MEK2, or rarely, KRAS genes. Here, we report a rare Tunisian case of CFC syndrome for whom we identify SOS1 mutation. Methods: Genomic DNA was obtained from peripheral blood collected in an EDTA tube and extracted from leukocytes using the phenol/chloroform method according to standard protocols. High resolution melting (HRM) analysis for screening of mutations in the entire coding sequence of PTPN11 was conducted first. Then, HRM assays to look for hot spot mutations coding regions of the other genes of the RAS-MAPK pathway (RAt Sarcoma viral oncogene homolog Mitogen-Activated Protein Kinases Pathway): SOS1, SHOC2, KRAS, RAF1, KRAS, NRAS, CBL, BRAF, MEK1, MEK2, HRAS, and RIT1, were applied. Results: Heterozygous SOS1 point mutation clustered in exon 10, which encodes for the PH domain of SOS1, was identified: c.1655 G > A. The patient was a 9-year-old female born from a consanguineous couple. She exhibited pulmonic valvular stenosis as congenital heart disease. She had facial features and other malformations of Noonan syndrome, including macrocephaly, hypertelorism, ptosis, downslanting palpebral fissures, sparse eyebrows, a short and broad nose with upturned tip, low-set ears, high forehead commonly associated with bitemporal narrowing and prominent supraorbital ridges, short and/or webbed neck and short stature. However, the phenotype is also suggestive of CFC syndrome with the presence of more severe ectodermal abnormalities, including curly hair, keloid scars, hyperkeratotic skin, deep plantar creases, and delayed permanent dentition with agenesis of the right maxillary first molar. Moreover, the familial history of the patient revealed recurrent brain malignancies in the paternal family and epileptic disease in the maternal family. Conclusions: This case report of an overlapping RASopathy associated with SOS1 mutation and familial history of brain tumorigenesis is exceptional. The evidence suggests that RASopathies are truly cancer-prone syndromes, but the magnitude of the cancer risk and the types of cancer partially overlap.

Keywords: cardiofaciocutaneous syndrome, CFC, SOS1, brain cancer, germline mutation

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3 Study of Silent Myocardial Ischemia in Type 2 Diabeic Males: Egyptian Experience

Authors: Ali Kassem, Yhea Kishik, Ali Hassan, Mohamed Abdelwahab

Abstract:

Introduction: Accelerated coronary and peripheral vascular atherosclerosis is one of the most common and chronic complications of diabetes mellitus. A recent aspect of coronary artery disease in this condition is its silent nature. The aim of the work: Detection of the prevalence of silent myocardial ischemia (SMI) in Upper Egypt type 2 diabetic males and to select male diabetic population who should be screened for SMI. Patients and methods: 100 type 2 diabetic male patients with a negative history of angina or anginal equivalent symptoms and 30 healthy control were included. Full medical history and thorough clinical examination were done for all participants. Fasting and post prandial blood glucose level, lipid profile, (HbA1c), microalbuminuria, and C-reactive protein were done for all participants Resting ECG, trans-thoracic echocardiography, treadmill exercise ECG, myocardial perfusion imaging were done for all participants and patients positive for one or more NITs were subjected for coronary angiography. Results Twenty nine patients (29%) were positive for one or more NITs in the patients group compared to only one case (3.3%) in the controls. After coronary angiography, 20 patients were positive for significant coronary artery stenosis in the patients group, while it was refused to be done by the patient in the controls. There were statistical significant difference between the two groups regarding, hypertension, dyslipidemia and obesity, family history of DM and IHD with higher levels of microalbuminuria, C-reactive protein, total lipids in patient group versus controls According to coronary angiography, patients were subdivided into two subgroups, 20 positive for SMI (positive for coronary angiography) and 80 negative for SMI (negative for coronary angiography). No statistical difference regarding family history of DM and type of diabetic therapy was found between the two subgroups. Yet, smoking, hypertension, obesity, dyslipidemia and family history of IHD were significantly higher in diabetics positive versus those negative for SMI. 90% of patients in subgroup positive for SMI had two or more cardiac risk factors while only two patients had one cardiac risk factor (10%). Uncontrolled DM was detected more in patients positive for SMI. Diabetic complications were more prevalent in patients positive for SMI versus those negative for SMI. Most of the patients positive for SMI have DM more than 5 years duration. Resting ECG and resting Echo detected only 6 and 11 cases, respectively, of the 20 positive cases in group positive for SMI compared to treadmill exercise ECG and myocardial perfusion imaging that detected 16 and 18 cases respectively, Conclusion: Type 2 diabetic male patients should be screened for detection of SMI when aged above 50 years old, diabetes duration is more than 5 years, presence of two or more cardiac risk factors and/or patients suffering from one or more of the chronic diabetic complications. CRP, is an important parameter for selection of type 2 diabetic male patients who should be screened for SMI. Non invasive cardiac tests are reliable for screening of SMI in these patients in our locality.

Keywords: C-reactive protein, Silent myocardial ischemia, Stress tests, type 2 DM

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2 Prediction of Endotracheal Tube Size in Children by Predicting Subglottic Diameter Using Ultrasonographic Measurement versus Traditional Formulas

Authors: Parul Jindal, Shubhi Singh, Priya Ramakrishnan, Shailender Raghuvanshi

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Background: Knowledge of the influence of the age of the child on laryngeal dimensions is essential for all practitioners who are dealing with paediatric airway. Choosing the correct endotracheal tube (ETT) size is a crucial step in pediatric patients because a large-sized tube may cause complications like post-extubation stridor and subglottic stenosis. On the other hand with a smaller tube, there will be increased gas flow resistance, aspiration risk, poor ventilation, inaccurate monitoring of end-tidal gases and reintubation may also be required with a different size of the tracheal tube. Recent advancement in ultrasonography (USG) techniques should now allow for accurate and descriptive evaluation of pediatric airway. Aims and objectives: This study was planned to determine the accuracy of Ultrasonography (USG) to assess the appropriate ETT size and compare it with physical indices based formulae. Methods: After obtaining approval from Institute’s Ethical and Research committee, and parental written and informed consent, the study was conducted on 100 subjects of either sex between 12-60 months of age, undergoing various elective surgeries under general anesthesia requiring endotracheal intubation. The same experienced radiologist performed ultrasonography. The transverse diameter was measured at the level of cricoids cartilage by USG. After USG, general anesthesia was administered using standard techniques followed by the institute. An experienced anesthesiologist performed the endotracheal intubations with uncuffed endotracheal tube (Portex Tracheal Tube Smiths Medical India Pvt. Ltd.) with Murphy’s eye. He was unaware of the finding of the ultrasonography. The tracheal tube was considered best fit if air leak was satisfactory at 15-20 cm H₂O of airway pressure. The obtained values were compared with the values of endotracheal tube size calculated by ultrasonography, various age, height, weight-based formulas and diameter of right and left little finger. The correlation of the size of the endotracheal tube by different modalities was done and Pearson's correlation coefficient was obtained. The comparison of the mean size of the endotracheal tube by ultrasonography and by traditional formula was done by the Friedman’s test and Wilcoxon sign-rank test. Results: The predicted tube size was equal to best fit and best determined by ultrasonography (100%) followed by comparison to left little finger (98%) and right little finger (97%) and age-based formula (95%) followed by multivariate formula (83%) and body length (81%) formula. According to Pearson`s correlation, there was a moderate correlation of best fit endotracheal tube with endotracheal tube size by age-based formula (r=0.743), body length based formula (r=0.683), right little finger based formula (r=0.587), left little finger based formula (r=0.587) and multivariate formula (r=0.741). There was a strong correlation with ultrasonography (r=0.943). Ultrasonography was the most sensitive (100%) method of prediction followed by comparison to left (98%) and right (97%) little finger and age-based formula (95%), the multivariate formula had an even lesser sensitivity (83%) whereas body length based formula was least sensitive with a sensitivity of 78%. Conclusion: USG is a reliable method of estimation of subglottic diameter and for prediction of ETT size in children.

Keywords: endotracheal intubation, pediatric airway, subglottic diameter, traditional formulas, ultrasonography

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1 Categorical Metadata Encoding Schemes for Arteriovenous Fistula Blood Flow Sound Classification: Scaling Numerical Representations Leads to Improved Performance

Authors: George Zhou, Yunchan Chen, Candace Chien

Abstract:

Kidney replacement therapy is the current standard of care for end-stage renal diseases. In-center or home hemodialysis remains an integral component of the therapeutic regimen. Arteriovenous fistulas (AVF) make up the vascular circuit through which blood is filtered and returned. Naturally, AVF patency determines whether adequate clearance and filtration can be achieved and directly influences clinical outcomes. Our aim was to build a deep learning model for automated AVF stenosis screening based on the sound of blood flow through the AVF. A total of 311 patients with AVF were enrolled in this study. Blood flow sounds were collected using a digital stethoscope. For each patient, blood flow sounds were collected at 6 different locations along the patient’s AVF. The 6 locations are artery, anastomosis, distal vein, middle vein, proximal vein, and venous arch. A total of 1866 sounds were collected. The blood flow sounds are labeled as “patent” (normal) or “stenotic” (abnormal). The labels are validated from concurrent ultrasound. Our dataset included 1527 “patent” and 339 “stenotic” sounds. We show that blood flow sounds vary significantly along the AVF. For example, the blood flow sound is loudest at the anastomosis site and softest at the cephalic arch. Contextualizing the sound with location metadata significantly improves classification performance. How to encode and incorporate categorical metadata is an active area of research1. Herein, we study ordinal (i.e., integer) encoding schemes. The numerical representation is concatenated to the flattened feature vector. We train a vision transformer (ViT) on spectrogram image representations of the sound and demonstrate that using scalar multiples of our integer encodings improves classification performance. Models are evaluated using a 10-fold cross-validation procedure. The baseline performance of our ViT without any location metadata achieves an AuROC and AuPRC of 0.68 ± 0.05 and 0.28 ± 0.09, respectively. Using the following encodings of Artery:0; Arch: 1; Proximal: 2; Middle: 3; Distal 4: Anastomosis: 5, the ViT achieves an AuROC and AuPRC of 0.69 ± 0.06 and 0.30 ± 0.10, respectively. Using the following encodings of Artery:0; Arch: 10; Proximal: 20; Middle: 30; Distal 40: Anastomosis: 50, the ViT achieves an AuROC and AuPRC of 0.74 ± 0.06 and 0.38 ± 0.10, respectively. Using the following encodings of Artery:0; Arch: 100; Proximal: 200; Middle: 300; Distal 400: Anastomosis: 500, the ViT achieves an AuROC and AuPRC of 0.78 ± 0.06 and 0.43 ± 0.11. respectively. Interestingly, we see that using increasing scalar multiples of our integer encoding scheme (i.e., encoding “venous arch” as 1,10,100) results in progressively improved performance. In theory, the integer values do not matter since we are optimizing the same loss function; the model can learn to increase or decrease the weights associated with location encodings and converge on the same solution. However, in the setting of limited data and computation resources, increasing the importance at initialization either leads to faster convergence or helps the model escape a local minimum.

Keywords: arteriovenous fistula, blood flow sounds, metadata encoding, deep learning

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