John V. Segas
National and Kapodistrian University of Athens
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Otolaryngology-Head and Neck Surgery | 2006
John Xenellis; Nikolaos Papadimitriou; Thomas Nikolopoulos; Paulos Maragoudakis; John V. Segas; Antonios Tzagaroulakis; Eleutherios Ferekidis
BACKGROUND AND OBJECTIVE: Although systemic steroids in sudden sensorineural hearing loss (SSHL) appears to be the most effective and the most widely accepted treatment today, a significant number of patients do not respond to steroid treatment or they cannot receive steroids for medical reasons. Intratympanic (IT) administration of steroids appears to be an alternative or additional method of management without the side effects of intravenous steroids. The aim of this study is to investigate the effectiveness and safeness of IT administration of steroids in patients who had not responded to IV treatment and to compare treatment efficacy with controls. STUDY DESIGN AND SETTING: Our study consisted of 37 patients with SSHL who, at the end of 10 days of therapy with intravenous steroids as a 1st line treatment, had pure-tone 4-frequency (0.5, 1, 2, and 4 kHz) average (PTA) of worse than 30 dB or worse than 10 dB from the contralateral ear (defined as failed intravenous treatment). They were randomized into 2 groups, treatment and control. The 19 patients of the treatment group received approximately 0.5 mL sterile aqueous suspension of methylprednisolone acetate in a concentration of 80 mg/2 mL by direct injection. The procedure was carried out 4 times within a 15-day period. An audiogram was performed before each injection and approximately 1.5 months after the last session. RESULTS: All patients tolerated the procedure well. No perforation or infection was noticed in any of the patients at their last visit. With regard to the 19 patients who received intratympanic treatment, in 9 patients, the PTA threshold improved more than 10 db, in 10 patients there was no change greater than 10 db, and no patients deteriorated more than 10 db. In the control group, none of the patients showed any change greater than 10 db. The difference was statistically significant (P = 0.002). The treatment group showed an improvement in mean PTA of 14.9 dB, whereas the control group showed a deterioration of 0.8 dB, and this difference also was statistically significant (P = 0.0005). IT treatment (P = 0.0001), better post-IV PTA (P = 0.0008), and absence of vertigo (P = 0.02) were good predictors of the outcome. In contrast, sex, age, affected ear, days to admission, and pattern of the initial audiogram showed no significant influence on the outcome. CONCLUSION AND SIGNIFICANCE: IT steroid administration after failed intravenous steroids is a safe and effective treatment in sudden sensorineural hearing loss.
International Journal of Pediatric Otorhinolaryngology | 2001
Pelagia Stavroulaki; Nikolaos Apostolopoulos; John V. Segas; Michalis Tsakanikos; George Adamopoulos
OBJECTIVES Cisplatin chemotherapy is associated with an increased risk of ototoxic changes. The incidence of hearing loss after the 1st cisplatin-infusion session is only scarcely mentioned in the international literature. With increasing survival rates, prevention and/or early detection of ototoxicity are important for providing management options. The predictive value of pure-tone audiometry in early detection of ototoxicity has been questioned, particularly in the higher frequencies. Otoacoustic emissions appear to be more sensitive to cochlear insult than the conventional pure-tone audiometry. The aims of our study was (a) to define the extent of hearing damage in children after the 1st cisplatin-infusion session (50 mg/m(2)); and (b) to compare the efficacy of otoacoustic emissions (transient evoked otoacoustic emissions, distortion-product otoacoustic emissions) with that of pure-tone audiometry as methods of audiological monitoring. METHODS Baseline audiometric (0.25-8 kHz) and otoacoustic emission testing (transient evoked otoacoustic emissions, distortion-product otoacoustic emissions) was conducted in 19 children, 12 of whom met the criteria for inclusion in the final study. Comparisons were performed between baseline measurements and those recorded after the 1st cisplatin course. Transient evoked otoacoustic emissions were analyzed in terms of emission level and reproducibility as a function of frequency (0.8-4 kHz). Distortion-product otoacoustic emissions were obtained as DP-grams and I/Q functions at 4,6 and 8 kHz. The DP-gram amplitude, the dynamic range and the detection thresholds from the I/Q functions were determined for each child. RESULTS Threshold changes from baseline were founded to be statistically significant from 4-8 kHz in 50% of the children (P<0.01). Transient evoked otoacoustic emissions revealed a significant decrease in the emission level and in the reproducibility at the highest frequency tested (4 kHz, P<0.01), reflecting the results seen in pure-tone audiometry. Distortion-product otoacoustic emissions demonstrated a significant threshold shift, a reduced dynamic range and a decreased amplitude in the frequencies >3 kHz (P<0.05). Furthermore, DP-gram amplitude also reduced significantly at 3 kHz (P<0.05) without any similar change in pure-tone audiometry. CONCLUSIONS A significant high-frequency hearing loss is identified in children even after one low-dose cisplatin-infusion session. As ototoxicity screening tools DP-grams were extremely sensitive and superior to pure-tone audiometry and/or transient evoked otoacoustic emissions. Their use is recommended for regular monitoring of cochlear function, aiming in prevention of permanent damage. Some suggestions for reducing the potential for cisplatin ototoxicity (chemoprotective agents, gene therapy, inhibition of apoptosis) are also discussed.
Head and Neck-journal for The Sciences and Specialties of The Head and Neck | 1999
Karen T. Pitman; Emmanuel P. Prokopakis; Barlas Aydogan; John V. Segas; Ricardo L. Carrau; Carl H. Snyderman; Ivo P. Janecka; Ehab Y. Hanna; Frank D'Amico; Jonas T. Johnson
Adenoid cystic carcinoma (ACC) of the sinonasal tract is an aggressive malignancy associated with a poor 5‐year survival rate. The role of skull base surgery for the treatment of patients presenting with sinonasal ACC and its impact upon their survival has not previously been evaluated.
American Journal of Otolaryngology | 1995
Dimitrios Kandiloros; John V. Segas; Konstantina Papadimitriou; Panagiotis Koutsomanis; George Adamopoulos
(Editor’s Comment: The observations of oncocytic change in the contralateral gland raises the possibility of progression to malignancy.) The oncocytoma is a rare but well-known tumor of salivary gland origin, and it is generally regarded as benign. Various synonyms have been applied to this neoplasm (ie, oxyphilic adenoma, oxyphilic granular-cell adenoma, and oncocytic adenoma).l The hallmark of oncocytomas is the presence of true oncocytes. These true oncocytes are large epithelial cells with a distinctly eosinophilic, finely granular cytoplasm and a rounded vesicular nucleus that is usually centrally placed. These cells contain numerous mitochondria and enzymes on electronmicroscopic and histochemical studies.2*3 Oncocytes are commonly present in the parotid salivary gland, but they have been observed in other major and minor salivary glands; in the mucous glands of the larynx, trachea, bronchi, and esophagus; in the lacrimal glands; in the nasal mucous membrane; in the thyroid, parathyroid, and pancreas; in both lobes of the hypophysis; in testicle and fallopian tubes; in the liver; and in the stomach.4 Neoplastic oncocytomas arise in the parotid gland, the submaxillary gland, and the minor salivary glands. Their incidence varies from 0.5% to 1.2% of all parotid gland tumors.5-7 They are nearly always found in persons over 50 years old and in increasing numbers they are found in persons from 50 to 70 years old.*
Clinical Pediatrics | 2013
Petros V. Vlastarakos; Melpomeni Fetta; John V. Segas; Pavlos Maragoudakis; Thomas P. Nikolopoulos
Aim. To assess the current knowledge and evaluate the quality of evidence in the use of FESS for the treatment of chronic rhinosinusitis in children, regarding the respective changes in the quality-of-their-life (QoL) and the outcome that follows the operation. Materials/Methods. Systematic literature review in Medline and other database sources and meta-analysis of pooled data. Results. 15 studies were systematically analyzed. Four represented Level II, five Level III, and six Level IV evidence. The total number of treated patients was 1301. Thirteen research groups reported that pediatric FESS is an effective treatment for chronic rhinosinusitis; the respective positive outcome ranged between 71 and 100% of operated children. Five studies concluded that this treatment modality is associated with significant improvement in the children’s postoperative QoL. Systemic diseases and environmental factors may have unfavourable prognostic effects; cystic fibrosis is associated with at least 50% recurrence rate. The rate of major complications following pediatric FESS is 0.6%, and the respective rate of minor complications 2%. Conclusion. The surgical management in children with chronic rhinosinusitis, despite the reservations expressed by many clinicians, is effective when optimal medical treatment proves unsuccessful (grade B strength of recommendation), and is associated with improvement in the children’s QoL (grade B strength of recommendation). FESS also improves the sinusitis-associated symptoms and QoL in children with cystic fibrosis (grade C strength of recommendation. Most complications of pediatric FESS reported in the literature are minor, and associated with difficulties in the postoperative assessment and care of pediatric patients.
Journal of Laryngology and Otology | 1999
Leonidas Manolopoulos; P. Stavroulaki; John Yiotakis; John V. Segas; G. Adamopoulos
Laryngeal obstruction due to bilateral vocal fold paralysis has been treated in many different ways. The CO2 laser or KTP-532 laser endoscopic cordectomy described in this report is a slight modification of the posterior partial cordectomy proposed by Dennis and Kashima. This technique was used in 18 patients (14 with the CO2 and four with the KTP-532 laser). Prophylactic tracheostomy was performed pre-operatively. Post-operative results were excellent in nine cases, good in seven cases and poor in two cases who had to remain with a permanent tracheostomy tube with a speaking valve. The main complications noted were the formation of a granuloma (seven cases) and arytenoid oedema (six cases). Revision surgery was performed in the seven cases with granuloma formation and in the two with persistent oedema. The results and the post-operative findings from the use of the two lasers were similar.
Operations Research Letters | 2005
John V. Segas; Andreas C. Lazaris; Thomas Nikolopoulos; Nikolaos Kavantzas; Irene E. Lendari; Antonios M. Tzagkaroulakis; Efstratios Patsouris; Eleftherios Ferekidis
Cyclin D1 (CCND1) is a set of periodic regulatory proteins that is believed to govern cell cycle transit from G1 into S phase. Overexpression of CCND1 leads to abnormal cellular proliferation which underlies processes of tumorigenesis; CCND1 can thus function as a cooperative oncogene in cell transformation. In the present study we investigate the immunohistochemical expression of CCND1 in a well-documented series of 58 laryngeal squamous cell carcinomas (LSCC) and search for statistical associations between CCND1 index and various clinicopathological parameters including several immunomarkers’ expression as well as patients’ disease-free survival. Tissue sections from archival paraffin blocks were stained using the avidin-biotin-peroxidase complex method; the H-295 rabbit polyclonal antibody was applied at dilution of 1:150. The percentage of CCND1 immunoreactive tumor cells for each tumor was counted by an image analysis system. CCND1 staining was confined to cell nuclei and, in the examined samples, ranged from undetectable (i.e. 0% of tumor cells, n = 6) to the majority of tumor cells (i.e. 89% of tumor cells) with mean value: 15.73%. In tumor adjacent, non invasive lesions, strong CCND1 staining was noticed in areas with cellular atypia. In cases with nodal metastases, no change in CCND1 expression in the nodal metastases compared with the primary tumors was observed. p53 protein accumulation in malignant cells was positively linked with CCND1 index (Mann-Whitney U: 205.5, p = 0.034). CCND1 expression appears to be an early event in processes of tumorigenesis and tumor progression in some LSCC. Apart from p53 protein accumulation, CCND1 immunohistochemical expression does not seem to correlate with nodal metastasis, disease recurrence or any other clinicopathological prognostic indicator.
European Archives of Oto-rhino-laryngology | 1994
Ricardo L. Carrau; John V. Segas; Nuss Dw; Carl H. Snyderman; Jonas T. Johnson
Sarcomas of the nose and paranasal sinuses are rare neoplasms and comprise less than 1% of the malignancies arising in the sinonasal tract. From 1977 to 1989, we had the opportunity to treat 15 patients presenting with these tumors at The Eye & Ear Institute of the University of Pittsburgh. The clinical charts of these patients were reviewed retrospectively for demographic data, characteristics of disease, treatment considerations and clinical outcome. Data were also analyzed with special attention to the role of skull base surgery for the local control of tumors. Seven patients underwent cranial base surgery as part of their original therapy. Two of these patients are alive with no evidence of disease, one patient died of other causes, and four are dead of disease. Two patients died with local disease. Although not statistically significant due to the small number of patients, these data suggest that cranial base surgery can improve the local control of sarcomas of the sinonasal tract that approach or invade the skull base.
Acta Oto-laryngologica | 2001
John V. Segas; Anastassios G. Hantzakos; Antonios Tzagaroulakis; George K. Adamapoulos
Pyriform sinus carcinoma is a highly malignant carcinoma of the head and neck region as a result of its location and its potential for metastatic spread. Decisions regarding the operative procedure remain very difficult. In this paper, we present a modified partial laryngo-pharyngectomy in which, following extended vertical laryngectomy, the cancerous mass is removed from the involved pyriform sinus and the remaining hypopharynx is reconstructed by using the preserved outer perichondrium of the resected thyroid cartilage. This technique has been applied with adequate success during the last five years in five cases in our department. It is indicated when a pyriform sinus carcinoma does not extend to the pyriform apex and does not involve the anterior and posterior laryngeal commissures, paraglottic space, retrocricoid region and posterior pharyngeal wall beyond the midline. All patients treated were male and middle-aged. Our technique appears to be a reliable alternative for the operative treatment of pyriform sinus carcinoma.
Laryngoscope | 1999
Ricardo L. Carrau; John V. Segas; Daniel W. Nuss; Carl H. Snyderman; Ivo P. Janecka; Eugene N. Myers; Frank D'Amico; Jonas T. Johnson