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R Dergenc

Publications and source records attributed to R Dergenc.

9 recordsLinked to original sources
PubMed2005

Mast cells in chronic inflammation of the middle ear mucosa.

AIM OF THE STUDY: The number, distribution and degranulation frequency of mast cells have been studied in the middle ear mucosa biopsies of patients with chronic otitis media. MATERIALS AND METHODS: The pathohistological analysis has been performed on 115 biopsy specimens, taken intraoperatively from the different regions of the middle ear cleft in 27 patients with chronic otitis media and in 15 children with otomastoiditis which occurred during the treatment of secretory otitis media. Mast cells were identified on the basis of metachromatic staining for histamine and heparin granules. RESULTS: The findings of this study confirm that the number of mast cells is increased in all areas of middle ear cleft in chronic inflammation of the middle ear mucosa. Mast cells were identified in 108 out of 115 analysed samples. In chronic otitis media of atticoantral and tubotympanic type mast cells were present in 91.5% of samples, the cells with heparin granules were present in 62.2% and degranulation frequency was 37.8%. In secretory otitis media 33 mucosal samples were analysed and all samples contained mast cells with predominance of histamine granules and with de granulation frequency of 81.8%. CONCLUSION: These findings indicate that mast cells have complex function in pathophysiology of chronic inflammation of the middle ear mucosa: it may take part in amplification of inflammation as well as in its limitation. Further studies are needed to clarify the role of histamine and heparin in chronic inflammatory reactions of the middle ear mucosa.

Adult↗
PubMed1992

On the capability of the vestibular apparatus to perceive sound stimuli.

This paper discusses the capacity of sound perception in 5 profoundly deaf subjects in whom a "fenestra" was previously formated on the lateral semicircular canal. The ability of sound and vibration perception after fenestra formation in profoundly deaf subjects with normal function of the vestibular apparatus has been described previously. The experiments for this procedure were done on pigeons by Wit & Bleeker. The subjects aged from 22 to 34 years. Causes of deafness varied. Their hearing threshold was bilaterally higher than 95 dB HL and their vestibular apparatus was of normal excitability bilaterally when tested with a caloric test. In all 5 patients the ear conduction hearing threshold remained the same, but the ability of vibration perception improved significantly, and ranged postoperatively between 30 and 45 dB HL. The frequency dynamic range was from 125 to 2,000 Hz in 4 subjects, and from 125 to 4,000 Hz in 1 subject. The patients claimed to have perceived higher intensities, but with a variable dynamic range from frequency to frequency. The intensity range amounted to between 15 and 40 dB. The obtained data of vibration perception ability are discussed.

Adult↗
PubMedDate not supplied

[Surgical treatment of secretory otitis media: persistent perforation as a rare complication].

INTRODUCTION: The persistent perforation of the ear drum may appear as a complication after spontaneous or instrumental elimination of ventilatory tubes during surgical management of secretory otitis media. According to recent literature data its incidence can vary in an average interval from 0.5 to 3.4% for the short term ventilatory tubes and more than 8.5% for long term ventilatory tubes. This study showed the results of analysis of the incidence and therapy of persistent perforation of the ear drum after elimination of the short term ventilatory tubes during the treatment of secretory otitis media in 1554 children, treated over the period from 1988 to 1997 at the Ward of ORL, Zvezdara Clinical and Hospital Centre in Belgrade. MATERIAL AND METHODS: The retrospective analysis of medical documentation showed that 1554 children were surgically treated by short term ventilatory tubes between 1988 and 1997. Bilateral insertion of the ventilatory tubes was performed in 1353 children (Sheppard short term tubes) and unilateral insertion was performed in 201 children. The age of the patients ranged from 9 months to 12 years. RESULTS AND DISCUSSION: After 2907 inserted short term ventilatory tubes 25 (0.86%) persistent perforations of the ear drum were diagnosed. The average time of elimination was 6-8 months after tubes insertion. In 3 cases, refreshment of the edges of perforation and silastic sheet placement led to complete closure of ear drum defect. In 16 patients myringoplasty was performed. According to literature data and our clinical experience, the main cause of this complication is the state of the ear drum which is a part of pathophysiological mechanisms in secretory otitis media. The histopathological studies of the ear drum in secretory otitis media confirmed various morphological changes: thickening of the ear drum, subepithelialo oedema, infiltration of submucous space by lymphocytes, macrophages and plasmocytes. Fibrous layer showed irregularly oriented fibroblasts and a high production of fibrous fibres. The interaction among extracellular tissue, cells of the submucous and subepithelial layer and cytokines causes the process of reparation of the ear drum. CONCLUSION: Persistent perforation of the ear drum is a rare complication during surgical treatment of secretory otitis media, but it has its great clinical importance if spontaneous repair does not appear. Depending on the mucosal status, ear discharge, Eustachian tubes function and immunological status or upper respiratory mucosa, myringoplasty is the method of therapeutical choice.

Child↗
PubMedDate not supplied

[Mastocytes in chronic inflammation of middle ear mucosa].

INTRODUCTION: Pathohistological studies have shown that in secretory otitis media an increased number of mast cells have been found in mucosa of the middle ear and an increased level of histamine in the cavity of the middle ear. The aim of this study was to analyse the distribution and functional state of mast cells in middle ear mucosa biopsies in patients with chronic otitis media. MATERIAL AND METHODS: The pathohistological analysis was performed on 118 biopsy specimens of mucosa of the middle ear. The samples were taken intraoperatively from 39 patients during the surgical treatment of chronic otitis media with and without cholesteatoma and otomastoiditis. The specimens were taken from mastoid, attic space, promantory and protympanon. All biopsy specimens were prepared for hematoxylin-eozin staining and were identified with PAS method and Lennert Giemsa histamine granules. The Alcian blue-Safranin method was used to identify heparin granules in mast cells. By using the semiquantitative method, distribution of mast cells was marked as rare (+), numerous (+2) and high (+3). Also the number of degranulated cells was identified (Tables 1, 2). RESULTS AND DISCUSSION: The analyses of biopsy specimens of mucosa of the middle ear in chronic otitis media showed that cells were present in all areas of mucosa in a considerably higher number (Table 1). Degranulated cells were frequently found in biopsy specimens of otomastoiditis and contained predominately histamine granules; thus specimens taken from chronic otitis media, with and without cholesteatoma, showed mast cells with heparin granules with low rate degranulation. Pathophysiological examinations of the role of mast cells in the mechanism of chronic inflammation have shown that mast cells display through mediators the biphasic effect. They can participate in the process of deterioration of inflammation, whereby the released mediators cause the processes of tissue destruction, and can stimulate the process of tissue repair. Heparin accelerates the healing process of tympanic membrane perforation, stimulates the proliferation of endothelial cells and supports angiogenesis in the lamina propria of the tympanic membrane. Further studies are needed to clarify the role of histamine and heparin in the pathophysiology of chronic inflammation in chronic otitis media.

Adolescent↗
PubMedDate not supplied

[Thrombophlebitis of the sigmoid sinus and otogenic sepsis].

Lateral sinus trombophlebitis and sepsis otogenes are rare complications of chronic osteitic otitis, but often resulting in delayed recognition and high mortality rate. During ten years in the period 1979-1989, we cured 5 patients with lateral sinus pathology and sepsis otogenes. All patients were successfully cured by surgical and conservative treatment. The incidence of these complications in our results confirm the events in recent literature that it is rare but complex condition with widespread clinical features which may range from subtle signs to gross toxaemia.

Adult↗