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Featured researches published by Zeynep Alkan.


Otolaryngology-Head and Neck Surgery | 2011

Histopathological Characteristics of Sulcus Vocalis

Ahmet Volkan Sunter; Ozgur Yigit; Gülben Erdem Huq; Zeynep Alkan; Ismail Kocak; Yalcın Buyuk

Objective. To describe the frequency of sulcus vocalis in a population and to establish its histopathological properties. Study Design. A cadaver study. Setting. Istanbul Training and Research Hospital and Ministry of Justice National Forensic Institute. Subjects and Methods. One hundred (21 women, 79 men) fresh cadaver larynges were examined. Two hundred vocal folds were coronally sectioned and examined by light microscopy. Sulcus types, depths, degree of fibrosis in Reinke space, basement membrane thickness, and perisulcus degeneration were determined. Results. Sulcus vocalis was found in 39 of 100 cases (39%), with a male preponderance of 41.8% compared with women at 28.6%. Twenty-one (54%) cases had unilateral and 18 (46%) cases had bilateral sulcus. Among 200 vocal folds, 57 had sulcus (28%). A total of 21 sulcus cases were type 1 (37%), 18 were type 2 (31.5%), and the remaining 18 cases were type 3 (31.5%). Of the 39 (30.7%) sulcus cases, 12 were confirmed by histopathological examination, although they looked morphologically normal following macroscopic evaluation. Vocal ligament involvement was found in 14 cases with type 2 (78%) and in 15 cases with type 3 sulcus (83%). Conclusion. Sulcus vocalis is a common pathology in the population and can be observed at all ages. The accuracy of diagnosis seems to depend on the measurement of the sulcus depth and the histological characteristics. For this reason, tools and strategies should be established in living subjects for effective management of this challenging disorder.


Laryngoscope | 2005

Cricopharyngeal Muscle Electromyography in Laryngopharyngeal Reflux

Münevver Çelik; Zeynep Alkan; Ibrahim Ercan; Hülya Ertasoglu; Canan Alkm; Levent Erdem; Suat Turgut; Cumhur Ertekin

Objectives/Hypothesis: The objective was to determine whether laryngopharyngeal reflux was associated with an electrophysiological abnormality of the main part of the upper esophageal sphincter, namely, the cricopharyngeal muscle, which could be related to laryngopharyngeal reflux symptoms.


International Journal of Pediatric Otorhinolaryngology | 2010

The role of matrix metalloproteinases in recurrent tonsillitis

Engin Acioglu; Ozgur Yigit; Zeynep Alkan; Ela Araz Server; Hafize Uzun; Ramisa Gelişgen

OBJECTIVE The aim of this study was to investigate the status of matrix metalloproteinases (MMP-2, MMP-7, MMP-9) and tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) due to dysregulated turnover of connective tissue matrices in children with recurrent tonsillitis (RT). METHODS Forty-four patients with RT were enrolled in the study. All patients with RT were graded according to the hypertrophy degree of the tonsillar tissue from grade I to grade IV. Patients with grade I tonsillar hypertrophy and grade II tonsillar hypertrophy were accepted as group A, patients with grade III tonsillar hypertrophy and grade IV tonsillar hypertrophy were accepted as group B Tonsillectomy was performed via the usual dissection-snare method. Tonsillar specimens of superficial and core region were evaluated for MMP-2, MMP-7, MMP-9 and TIMP-1 analysis. RESULTS There was no statistical significance according to the MMP-2, MMP-7, MMP-9 and TIMP-1 activity of superficial part and core regions in both groups individually, MMP-9 level of both the superficial and core regions in group B had statistical significant higher results than group A (p=0.026, p=0.06 respectively). MMP-7 level of the superficial part in group B patients also had statistical significant higher results than group A (p=0.025). However, there was no statistical difference found between superficial and core region MMP-2 and TIMP-1 levels of group A and group B. Related to this, balance between MMP-7-9 and TIMP-1 activities tended to slip MMP-7 and MMP-9 sides with increased tonsillar grade. CONCLUSIONS Results from this study suggest that the presence of MMPs in tonsil tissue consolidates the involvement of degraded extracellular matrix proteins in the pathophysiology of chronic tonsillitis. MMPs activity showed diffuse dissemination in the tonsillar tissue and especially MMP-9 and MMP-7 are the main promoters of the extracellular matrix that responded to inflammatory changes in the tonsillar tissue. Further studies are needed concerning the possible efficiency of selective MMP inhibitors on tonsillar tissue.


Archives of Facial Plastic Surgery | 2011

Tensile Characteristics of Costal and Septal Cartilages Used as Graft Materials

Zeynep Alkan; Ozgur Yigit; Engin Acioglu; Aylin Bekem; Elad Azizli; Ismail Kocak; Ahmet Unal; Yalcın Buyuk

OBJECTIVES To determine the biomechanical characteristics of septal cartilage (SC) and costal cartilage (CC) taken from fresh cadavers using tensile testing and to establish CC graft material of a suitable thickness (ie, with tensile characteristics closest to those of SC). METHODS Grafts of varying thickness were harvested from the central part of the seventh-rib CC and SC of 18 fresh cadavers. Tensile testing was performed with a 0.5-kilonewton load calibrated at 7 mm/min. The results were shown as a force-elongation curve. RESULTS No significant difference according to tensile force was observed between the SC group and the 1.0-mm and 1.5-mm CC groups (P = .09 and P = .32, respectively). However, a significant difference was observed between the SC group and the 2.0-mm CC group (P = .04). Although the strength value of the CC group was 5.03 MPa, the modulus of elasticity was 1.33 MPa. In the SC group, the strength value was 12.42, but the modulus of elasticity was 1.39 MPa. The strength value of the SC group was higher than that of the CC group (P = .001), but the modulus of elasticity value of the CC group was higher than that of the SC group (P = .001). CONCLUSIONS From the standpoint of tensile testing for preparing columellar struts, 1.0-mm and 1.5-mm CC have similar characteristics to SC and thus can be used instead of it. However, it is important to determine the thickness of CC by considering the expected characteristics of the established material and the forces that affect the area in the nose where the graft will be placed.


Otolaryngology-Head and Neck Surgery | 2012

Cricopharyngeal Muscle Electromyography Findings in Patients with Gastroesophageal Reflux Disease

Zeynep Alkan; Ahmet Demir; Ozgur Yigit; Turgut Adatepe; Besir Kesici; Ismail Kocak; Ays xe Pelin Gor; Umit Taskin; Nurten Uzun

Objective To analyze the grade of reflux and the behavior of the cricopharyngeal muscle (CPM) in patients with gastroesophageal reflux (GER) by means of electromyographic (EMG) analysis of CPM. Study Design Prospective clinical study. Setting Istanbul Training and Research Hospital. Subject and Methods Motor unit potential (MUP) recordings and kinesiological recordings of CPM were performed using a concentric needle electrode during dry material swallowing and 3-, 5-, and 10-mL water swallowing. Twenty-four patients with GER were compared with 21 healthy volunteers. Results GER was mild in 15 patients and moderate-to-severe in 9 patients. MUP recordings were normal in both groups during the preswallowing/postswallowing periods. Kinesiological investigations revealed that the number of patients who did not show a preswallow EMG burst had a positive correlation with the severity of reflux and the amount of liquid swallowed. Rebound bursts were observed in the patient and the control groups. Duration of preswallow and rebound bursts was similar in all groups. Duration of swallowing was shorter in mild GER patients compared with healthy volunteers and moderate-to-severe GER patients. Piecemeal deglutition during 10-mL liquid swallowing was higher in moderate-to-severe GER patients. We also found a positive correlation between the number of swallows and the severity of reflux. Conclusion Needle EMG of the upper esophageal sphincter was normal in GER patients. Kinesiological evaluations showed increased piecemeal deglutition and number of swallows that correlated positively with the severity of GER.


Otolaryngology-Head and Neck Surgery | 2012

Determining the Most Suitable Costal Cartilage Level for Rhinoplasty An Experimental Study

Zeynep Alkan; Engin Acioglu; Ozgur Yigit; Aylin Bekem; Elad Azizli; Ahmet Unal; Feyzi Sahin

Objective. The aim of this study was to compare the biomechanical properties of septal cartilage (SC) and costal cartilage (CC) grafts harvested from different ribs and to find at which level CC has characteristics closest to SC. Study Design. Experimental cadaver study. Setting. Istanbul Training and Research Hospital. Material and Method. Cartilage grafts were harvested from the 6th, 7th, and 8th ribs and the SC of 10 fresh cadavers. Shaped cartilage grafts were subjected to a bending test. Results were measured, and the force-deflection curve was plotted. Flexural strength (σf) and flexural modulus of elasticity (Ef) were determined. Fractured surfaces were evaluated by scanning electron microscopy (SEM). Results. According to Fmax, it was determined that ribs 6, 7, and 8 have significantly more durability compared with the SC (Ps = .030, .004, and .001). With regard to deflection, there was no significant difference between the SC and the 6th and 7th ribs and between the 6th and 7th ribs (Ps = 1.000, .088, and .306), while a significant difference was found between the SC and the 8th rib (P = .001). According to σf, no differences were seen between the 6th and 7th rib (P = .782), while difference was detected between the 6th and 8th and the 7th and 8th ribs (p = .001). Similar trends were established in Ef values as in σf. These results were confirmed by SEM images. Conclusion. The 7th CC can be used as autograft because it shows similar properties to SC. However, the 6th CC is preferred if more flexibility is desired, and the 8th CC is preferred where more strength is needed.


American Journal of Rhinology & Allergy | 2012

The effects of corticosteroid on tissue lactoferrin in patients with nasal polyposis.

Engin Acioglu; Ozgur Yigit; Zeynep Alkan; Elad Azizli; Ramisa Gelişgen; Hafize Uzun

Background Although, lactoferrin (LF) is the second most important antimicrobial and anti-inflammatory peptide after lysozyme in upper respiratory tract, little is known about its role in chronic rhinosinusitis (CRS). Recent studies pronounced that LF levels were significantly reduced in CRS with nasal polyposis (NP) compared with other subgroups. However, effects of systemic corticosteroid (CS) treatment, which is currently the main NP treatment modality, and subsequent surgical intervention on LF levels are still not known. This study was designed to evaluate the effects of CS treatment and surgical intervention on LF levels in patients with NP. Methods Patients with inflammatory NP who were scheduled to undergo CS treatment and a control group were included in this study. LF levels were determined from mucosal samples taken from both groups, before and after CS treatment, and also 1 month after surgical intervention. Results Twenty-seven patients with NP and 14 patients who underwent septoplasty were included in the study. Tissue LF levels were significantly lower in the NP group compared with the control group (p = 0.014). Tissue LF levels did not change significantly in NP patients after CS treatment. However, a significant reduction in tissue LF was detected 1 month after endoscopic sinus surgery. Conclusion Tissue LF concentrations significantly decreased in patients with NP. CS treatment had no effect on tissue LF levels, whereas postendoscopic sinus surgery, tissue LF levels were getting lower because there was also a reduction in inflammatory load (whether from reduction in mucosa surface area or resolution of disease).


Journal of Craniofacial Surgery | 2014

Assessment of cricopharyngeal muscle aging with apoptotic markers.

Ayse Pelin Gor; Zeynep Alkan; Ozgur Yigit; Nevra Dursun; Acioglu Engin; S.M. Akin; Bulent Sam

Objectives The aims of this study were to evaluate histochemical markers of apoptosis in the cricopharyngeus muscle, which is the gatekeeper of the pharyngoesophageal region during the swallowing process; to investigate the effects of primary aging on this muscle; and to determine whether a relationship exists with gastroesophageal reflux disease. Materials and Methods The study included 30 fresh cadavers with a time of death of 12 hours or less obtained from the Turkish Ministry of Justice Forensic Medicine Unit. All cadavers were dissected with routine postmortem skin incisions to extract specimens from the cricopharyngeus muscle and the esophagocardiac junction mucosa. Muscle degeneration and primary aging were demonstrated by immunodetection of Bax, Bcl-2, and Caspase-3 proteins as markers of the apoptosis. Esophageal specimens were examined for the presence of reflux esophagitis. Results The mean age was 41.5 (14–74) years, and the study included 18 male and 9 female cadavers. Three of them were excluded because of fixation artifacts. The mean Bax, Bcl-2, and Caspase scores showed no statistically significant relationship with age (P = 0.94). The right and left sides of the muscle were investigated separately, and the Bax scores of the right side of the cricopharyngeus muscle showed a statistically significant decrease with age (P = 0.026), whereas the Bax and Bcl-2 scores were increased with age (P = 0.035 and 0.049, respectively) on the left side. Evaluation of the 23 esophagus specimens revealed 10 cases of esophagitis. No relationship was found between the mean of each apoptotic marker and esophagitis. Conclusions It is histopathologically not possible to demonstrate muscle death due to either primary aging or reflux. This might be attributable to the defensive capability of this unique muscle to maintain the feeding process.


Rhinology | 2014

Importance of nasal septal cartilage perichondrium for septum strength mechanics: a cadaveric study.

Nihal Seden Tekke; Zeynep Alkan; Ozgur Yigit; Aylin Bekem; Ahmet Unal; Feyzi Sahin; Hasan Huseyin Balikci; Engin Acioglu; Yusuf Muhammed Durna

BACKGROUND According to the Federal Institution of Health Insurance, ENT doctors perform more skin prick tests for the diagnosis of allergic rhinitis (AR) than other medical specialties in Belgium. However, immunotherapy (IT) is not practiced by all. This study aims to obtain insight into IT practice by ENT doctors, the type of IT performed and the reasons not to perform IT. METHODOLOGY A questionnaire was sent to all registered ENT doctors of Belgium (n=648), involving questions on type and duration of ENT practice, geography and gender. In addition, the questionnaire informed about diagnosis of AR, indication for IT, type of IT performed, and reasons not to perform IT and referral pattern. RESULTS The response rate among ENT doctors was 54%, with 7% of responders being excluded as they do not diagnose AR. 81% of Belgian ENT doctors make the indication for IT in AR patients, with 19% neglecting the indication for IT in AR patients. The two main reasons for not indicating IT are lack of expertise and the perception of high costs associated with IT. 70% of ENT specialists are practicing IT themselves, with sublingual IT being mostly performed. Interestingly, IT is mostly frequently performed by those ENT doctors with long-standing ENT practice, in private practice and in Wallonia. CONCLUSION Despite the high prevalence of AR in ENT practice, IT is most frequently performed by ENT doctors with longstanding practice, working in private practice and/or in the French speaking part of Belgium. Among the different types of IT, sublingual IT is the most frequently performed means of IT by ENT doctors.OBJECTIVE To investigate the role of inflammation in non-allergic rhinitis (NAR) patients in a large series to establish the prevalence of different NAR-subtypes, clinical features and the role of nasal cytology in the diagnostic algorithm. METHODOLOGY Patients were selected out of 3650 individuals who spontaneously presented at our institution. We consecutively enrolled 519 NAR-patients in an analytical cross-sectional study between November 2007 and June 2013 (level of evidence: 3b). All patients underwent rhinological evaluation including symptoms questionnaire, endoscopy, CT scan, allergy tests and nasal cytology. RESULTS The inflammatory cell infiltrate affects the severity of symptoms differently, allowing for identification of different phenotypes of NAR. We distinguished two groups: “NAR without inflammation”(NAR-) and “NAR with inflammation”(NAR+), in addition to different NAR-subtypes with inflammation. A significant difference was observed in terms of clinical symptoms and association with comorbidities (previously diagnosed asthma and aspirin intolerance) between NAR–, NAR+ and between different NAR+ subtypes. CONCLUSION Our data suggest that NAR- and NAR with neutrophils behave similarly, showing lower symptom score values and a lower risk of association with comorbidities compared to NAR with eosinophils and mast cells (singularly or mixed). In our belief it is very important to establish the presence and type of inflammation in non-allergic rhinitis patients and nasal cytology is a very useful test in correct differential diagnosis.OBJECTIVE To assess the applicability of the Peak Nasal Inspiratory Flow (PNIF) curves in follow-up of children in the treatment of allergic rhinitis. METHODS Prospective study of 40 patients with AR, grouped in corticosteroid spray versus physiological saline solution use. Follow up for 10 weeks through clinical score and PNIF percentages in relation to the reference curves, with was-out at week 8. Statistical assessment of the effect of treatment on variation of PNIF and clinical score was calculated by ANOVA model and Multiple Comparison of Means Test - Least Significant Difference. RESULTS There was a statistically significant influence of the group, time and interaction between time and group on PNIF percentages. Throughout follow up, patients from the treatment group had mean PNIF percentages significantly higher than the placebo group. Clinical score results also demonstrated a statistically significant influence between the groups, time and interaction between time and group. CONCLUSION Increase in PNIF percentage values observed in children treated with intranasal corticosteroids revealed the applicability of PNIF curves in their follow up.OBJECTIVE This study aims to examine humans ́ abilities to localize odorants within the open field. METHODOLOGY Young participants were tested on a localization task using a relatively selective olfactory stimulus (2-phenylethyl-alcohol, PEA) and cineol, an odorant with a strong trigeminal component. Participants were blindfolded and had to localize an odorant source at 2 m distance (far-field condition) and a 0.4 m distance (near-field condition) with either two nostrils open or only one open nostril. RESULTS For the odorant with trigeminal properties, the number of correct trials did not differ when one or both nostrils were used, while more PEA localization trials were correctly completed with both rather than one nostril. In the near-field condition, correct localization was possible in 72-80% of the trials, irrespective of the odorant and the number of nostrils used. Localization accuracy, measured as spatial deviation from the olfactory source, was significantly higher in the near-field compared to the far-field condition, but independent of the odorant being localized. CONCLUSION Odorant localization within the open field is difficult, but possible. In contrast to the general view, humans seem to be able to exploit the two-nostril advantage with increasing task difficulty.BACKGROUND This study was designed to assess if illness perception, mood state and coping strategies differ according to allergic rhinitis (AR) persistence and severity. METHODS Illness perception, mood profiles, coping behaviors and rhinitis symptoms were assessed by means of validated tools inpatients classified according to the Allergic Rhinitis and Its Impact on Asthma (ARIA) guidelines. RESULTS Two hundred and thirty-one patients underwent data analysis. No difference in age, sex, socio-economic status, smoking habits was detected comparing patients according to AR severity, duration or 4 ARIA classes. Patients with intermittent AR reported higher scores than those with persistent AR in confusion-bewilderment of Profile of Mood States (POMS); patients with moderate/severe rhinitis had significantly higher scores than those with mild rhinitis in TSSS, Identity and Consequences. No differences were detected in all assessed outcomes in the 4 ARIA classes. CONCLUSIONS The patients perspective about AR is independent of persistence and severity of symptoms. This may explain why AR remains under-diagnosed and under-treated, even in its most severe forms. Self-management plans should consider the patients perspective.The assessment of Chronic Rhinosinusitis, like any other disease, may involve multiple possible disease manifestations, including subjective patient-reported outcomes, objective disease (e.g. endoscopy or radiographic), and physician-driven (e.g. need for systemic medications). Disease control is often used as a global metric of disease burden and represents the extent to which disease manifestations are within an acceptable range. Achieving control is an important treatment goal.The European Position Paper on Rhinosinusitis and Nasal Polyps 2020 is the update of similar evidence based position papers published in 2005 and 2007 and 2012(1-3). The core objective of the EPOS2020 guideline is to provide revised, up-to-date and clear evidence-based recommendations and integrated care pathways in ARS and CRS. EPOS2020 provides an update on the literature published and studies undertaken in the eight years since the EPOS2012 position paper was published and addresses areas not extensively covered in EPOS2012 such as paediatric CRS and sinus surgery. EPOS2020 also involves new stakeholders, including pharmacists and patients, and addresses new target users who have become more involved in the management and treatment of rhinosinusitis since the publication of the last EPOS document, including pharmacists, nurses, specialised care givers and indeed patients themselves, who employ increasing self-management of their condition using over the counter treatments. The document provides suggestions for future research in this area and offers updated guidance for definitions and outcome measurements in research in different settings.BACKGROUND Endoscopic dacryocystorhinostomy (EN-DCR) is a commonly used procedure in the treatment of nasolacrimal duct obstruction (NLDO). However, there is no generally accepted disease-specific questionnaire for assessing outcomes. METHODOLOGY We conducted a prospective study to initially validate a Nasolacrimal Duct Obstruction Symptom Score questionnaire(NLDO-SS) and to evaluate the long-term success of EN-DCR procedures. Seventy-six patients (86 eyes) were evaluated in follow-up visits at 1-8 years after EN-DCR. The patients completed the NLDO-SS questionnaire twice, first, at home and, second,after receiving information from the otorhinolaryngologist, during the visit. The surgical outcome was considered successful if the irrigation succeeded and if the patient symptoms were relieved as assessed with the NLDO-SS. RESULTS The diagnostic accuracy of the NLDO-SS was 84%, sensitivity 82%, specificity 85%, positive predictive value 58%, negative predictive value 95%, odds ratio 26, risk ratio 11 and usefulness index 0.55. Cronbachs alpha was 0.85, and the test-retest reliability coefficient was 0.87. The long-term success rate after EN-DCR was 79%. CONCLUSION The NLDO-SS iss a feasible clinical tool in assessing the success of EN-DCR. The success rate was found to decrease EN-DCR at long-term follow-up.


Head and Neck-journal for The Sciences and Specialties of The Head and Neck | 2012

Topographic description of an alternative insertion technique for percutaneous approach of cricopharyngeus muscle electromyography: A cadaveric and clinical study

Salih Murat Akkin; Zeynep Alkan; Ozgur Yigit; Turgut Adatepe; Mehmet Demirci; Juergen Koebke; Nurten Uzun

Cricopharyngeus is the only muscle for which electromyography is used in the differential diagnosis of swallowing disorders. Because of some practical difficulties, electrophysiologic tests for this muscle are not performed routinely. Thus we aimed to describe an alternative topographic way to reach the muscle easily.

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Ahmet Unal

Yıldız Technical University

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Aylin Bekem

Yıldız Technical University

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Ozgur Yigit

University of Health Sciences Antigua

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