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Sebahattin Cureoglu

Publications and source records attributed to Sebahattin Cureoglu.

At least 19 recordsLinked to original sources
PubMed2006

Age-related functional and histopathological changes of the ear in the MPS I mouse.

OBJECTIVE: Mucopolysaccharidosis type I (MPS I) is an autosomal recessive disorder caused by a mutation in the gene encoding the enzyme alpha-L-iduronidase. This enzyme is responsible for degradation of dermatan and heparan sulfates. Enzyme deficiency results in their accumulation in lysosomes of virtually all organs, resulting in severe somatic and neurological changes. Clinical findings of otitis media with mixed hearing loss are common. Cellular and molecular mechanisms of ear pathology and hearing loss are not understood. The purpose of this study is to describe the age-related audiologic and histopathologic changes of the ear in the mouse model of MPS I. METHODS: Auditory brainstem responses (ABR) were obtained to clicks and tone bursts at 1-32kHz, and pathological changes to middle and inner ears were studied with light and electron microscopy in 53 mice that included: (1) wild type (+/+)-five at 2 months, five at 4-6 months, and five at 13-19 months; (2) heterozygotes (+/-)-four at 2 months, five at 4-6 months, and eight at 13-19 months; and (3) homozygotes (-/-)-five at 2 months, six at 4-6 months, and five at 13-19 months. Histopathology was also done on five newborn -/- mice. RESULTS: In newborns, no lysosomal storage was observed and the ear appeared age appropriately normal. In all other -/- mice, cells with lysosomal storage vacuoles were observed in spiral ligament, spiral prominence, spiral limbus, basilar membrane, epithelial and mesothelial cells of Reissner's membrane, endothelial cells of vessels, and some ganglion cells; their number increased with aging. Hair cell loss was not observed at 2 or 6 months, but there was total loss of the organ of Corti in year-old mice. Hearing of -/- mice was significantly decreased at all ages compared to +/+ and +/-. Hearing loss progressed from mild to moderate loss at 2 months to profound at 6 months and total deafness by 1 year of age. CONCLUSIONS: Progressive age-related changes suggest early therapeutic intervention to prevent sensory cell damage and hearing loss.

Aging↗
PubMed2006

Association between cupular deposits and otosclerosis.

OBJECTIVE: To evaluate whether otosclerosis is an underlying mechanism for the production of cupular deposits and to study the association between cupular deposits and dysequilibrium in otosclerosis. DESIGN: Retrospective human temporal bone (TB) study. The incidence of cupular deposits in these 70 TBs was analyzed. Correlations between cupular deposits and vestibular symptoms, endosteal involvement of the otosclerotic focus, stapedial fixation, and clinical history of stapes surgery were evaluated. SETTING: Otolaryngology laboratory in a tertiary academic medical center. PATIENTS: The study material consisted of 35 human TBs with otosclerosis and 35 age-matched controls. MAIN OUTCOME MEASURES: Morphometric evaluations of the incidence of cupular deposits, endosteal involvement of the otosclerotic focus, and stapedial fixation were made by light microscopy. Clinical records were reviewed retrospectively for clinical history of stapes surgery and prevalence of vestibular symptoms. The incidence of cupular deposits was compared between the otosclerotic and control groups. Correlations between cupular deposits and vestibular symptoms, endosteal involvement of the otosclerotic focus, stapedial fixation, and clinical history of stapes surgery were evaluated in the subjects with otosclerosis. RESULTS: The incidence of cupular deposits in TBs with otosclerosis was significantly higher than in those without whereas there was no correlation between the incidence of the deposits and dysequilibrium in cases of otosclerosis. An increase in deposits did not correlate with stapedial fixation, stapes surgery, or endosteal involvement. CONCLUSIONS: Our results suggest otosclerosis as an underlying mechanism for the production of cupular deposits; however, we did not find an association between these deposits and vestibular symptoms.

Adult↗
PubMed2006

Effects of type 2 diabetes mellitus on cochlear structure in humans.

OBJECTIVE: To evaluate the effects of type 2 diabetes mellitus on cochlear elements in humans. DESIGN: Comparative study of the histopathologic characteristics of human temporal bones. SETTING: Otopathology laboratory in a tertiary academic medical center. PATIENTS: Temporal bones from 18 patients with type 2 diabetes mellitus were divided into 2 groups according to the method of management of diabetes: insulin in 11 patients (mean age, 51.9 years; age range, 44-65 years) and oral hypoglycemic agents in 7 patients (mean age, 54.4 years; age range, 45-64 years). The diabetic groups and 26 age-matched controls (mean age, 52.9 years) were examined using light microscopy, and the cochlear changes were compared between groups. MAIN OUTCOME MEASURES: Morphometric measurements of vessel wall thickness in the basilar membrane and stria vascularis were made in all turns of the cochlea at the midmodiolar level. Area measurements of the stria vascularis were made in all turns of the cochlea at the midmodiolar level. Cochlear reconstructions and standard cytocochleograms were prepared using an oil immersion objective. The number of spiral ganglion cells was determined for each segment of the cochlea. Comparisons were made in each segment between diabetic and control groups. RESULTS: In the insulin group, walls of the vessels of the basilar membrane and stria vascularis in all turns were significantly thicker than those of controls. Walls of the vessels of the stria vascularis in the basal turn were also significantly thicker in the oral hypoglycemic group than in controls. Atrophy of the stria vascularis in most turns of the insulin group and the lower middle turn of the oral hypoglycemic group was significantly greater than in the controls. Loss of cochlear outer hair cells was significantly greater in the lower and upper basal turns in both diabetic groups. No significant difference was found in the number of spiral ganglion cells or inner hair cells between groups. CONCLUSION: This study demonstrates that cochlear microangiopathy and degeneration of the stria vascularis and cochlear outer hair cells are found in patients with type 2 diabetes mellitus.

Administration, Oral↗
PubMed2006

Histologic changes in the anterior mallear ligament and the head of the malleus in otosclerosis.

OBJECTIVE: To determine ossicular and anterior mallear ligament (AML) changes in otosclerosis. STUDY DESIGN AND SETTING: Hyalinization of AML was graded as follows: none, patchy, or diffuse in 95 temporal bones (TBs) with otosclerosis: 52 with stapedial fixation (SF); 43 without fixation (NSF); and 52 age-matched controls. Fixation of the head of the malleus was noted. RESULTS: Hyalinization with SF was 17 none, 23 patchy, and 12 diffuse; with NSF it was 16 none, 20 patchy, and 7 diffuse; and in controls, 23 none, 24 patchy, and 5 diffuse. There was no significant difference in hyalinization among groups and no correlation between degree of hyalinization and age. The malleus head was fixed in 4 TBs with SF. CONCLUSION: Based on our findings, we do not believe that there is a relationship between hyalinization of the AML and otosclerosis; however, otosclerosis with SF seems to be a predisposing factor for fixation of the head of the malleus.

Adolescent↗
PubMed2006

TH1/TH2 and regulatory cytokines in adults with otitis media with effusion.

OBJECTIVE: Otitis media with effusion is one of the most common and intractable ear diseases. However, the role of Th1, Th2, and immunoregulatory cytokines on the pathogenesis of the disease in adult patients remains to be determined. The aim of this study is to disclose the cytokine expression in middle ear effusions (MEEs) in adults and to compare the profile on the basis of the presence of allergic rhinitis and the type of effusions. STUDY DESIGN: A prospective controlled clinical study. PATIENTS: MEEs were collected from 80 adult subjects. The concentration of interleukin (IL)-2, IL-4, IL-5, IL-10, IL-12, and interferon (IFN)-gamma in MEEs were determined by using enzyme-linked immunosorbent assay. RESULTS: IL-2, IL-4, IL-5, IL-10, IL-12, and IFN-gamma in MEEs were detected in 60 (75.0%), 33 (41.3%), 42 (52.5%), 14 (17.5%), 80 (100%), and 66 (82.5%) samples, respectively. Among these cytokines, only the concentration of IL-4 in the allergic rhinitis-positive group was significantly higher than that in the allergic rhinitis-negative group. On the other hand, IL-2, IL-12, and IFN-gamma were detected, regardless of the presence of allergic rhinitis, and the concentration of these cytokines correlated with each other. The correlation between the concentration of IL-4 and IL-5 was also detected. In addition, both the incidence rate and the concentration of IL-10 in MEEs were significantly higher in the mucoid type compared with those in the serous type effusions. CONCLUSION: Regardless of allergic status, IL-12 may play a critical role in the pathogenesis of otitis media with effusion by affecting the production of IL-2 and IFN-gamma. In addition, IL-4 may have some impact on the immunologic condition in adults with allergic rhinitis. IL-10 potentially affects the viscosity of MEEs.

Adult↗
PubMed2006

Large vestibular aqueduct syndrome: a human temporal bone study.

OBJECTIVES/HYPOTHESIS: Large vestibular aqueduct syndrome (LVAS) is one of the common causes of hearing loss (HL). All prior studies have reported some anomalies associated with LVAS by imaging techniques. This study was undertaken to determine prevalence of LVAS in our temporal bone (TB) collection and its relationship to other systemic or otologic anomalies. STUDY DESIGN: Retrospective, TB histopathologic study. METHODS: Anteroposterior diameters of internal (IA) and external (EA) apertures were measured in 40 normal TBs (40 cases). TBs were considered as large vestibular aqueduct (LVA) if width of apertures was 95% greater than "normals." Systemic and otologic anomalies and histopathology of ears with LVAS were noted. RESULT: Of 1,608 non-"normal" TBs, 63 had LVA. There was negative correlation between IA and EA in 48 TBs with only enlarged IA. Fifteen TBs with enlarged EA always had enlarged IA and were therefore considered as LVAS. The most common pathologic condition was congenital heart anomaly. The most common syndrome or dysplasia was Mondini's. The most common anomalies of external and middle ears were dehiscent facial nerves, low set auricles, and ossicular deformities. Inner ear anomalies included modiolar deficiencies, hair cell loss, interscalar septum defects, and strial atrophy. There was no record of family history of HL, head injury, or craniofacial, branchial, or thyroidal abnormalities. CONCLUSION: Because HL associated with LVAS may be attributed to other ear anomalies, it is important to investigate other inner ear problems and system diagnoses that may indicate a syndrome in patients with radiologically diagnosed LVAS.

Adolescent↗
PubMed2005

Follow-up results in tuberculous cervical lymphadenitis.

OBJECTIVE: To investigate the efficacy of medical antituberculous treatment in patients with tuberculous cervical lymphadenitis (TCL). METHODS: In the period 1996-2002, 73 TCL patients were reviewed and the results of clinical and laboratory testing were documented. The efficacy of a four-drug chemotherapy regimen was investigated. RESULTS: Purified protein derivatives (PPD) skin test results were positive in 58 (79 per cent) patients. Chest X-rays revealed changes consistent with tuberculosis in nine (12.3 per cent) patients. The mean duration of medical treatment was 10.04 months. In follow-up evaluation, 14 (20 per cent) patients were considered suspicious for resistant TCL and total excision of all nodes was performed. Histopathology confirmed TB in only 10 of these cases. CONCLUSION: The high incidence of residual disease in our study indicates that medical treatment (at least nine months of four combined antituberculous drugs) did not seem to be effective. If lymphadenopathy persists, total surgical excision of lymph nodes should be the treatment of choice.

Adolescent↗
PubMed2005

Cochlear changes in patients with type 1 diabetes mellitus.

OBJECTIVE: To evaluate the effects of diabetes on cochlear elements in human beings. STUDY DESIGN AND SETTING: Twenty-six temporal bones (mean age, 37.5 years) with type 1 diabetes and 30 age-matched controls were examined by light microscopy. We compared the findings of cochlear vessels, hair cells, spiral ganglion cells, and cochlear lateral walls. RESULTS: In diabetics, the walls of vessels of the basilar membrane (P < 0.001) and vessels of the stria vascularis were (P < 0.01) significantly thicker in all turns and loss of outer hair cells (OHCs) was significantly greater in the lower basal turn (P < 0.01). Atrophy of the stria vascularis in all turns (P < 0.0001) and loss of spiral ligament cells in upper turns (P < 0.01) were significantly higher than controls. No significant difference was obtained in the number of spiral ganglion cells between groups. CONCLUSION: This study suggests that type 1 diabetes mellitus can cause cochlear microangiopathy and subsequently degeneration of cochlear lateral walls and OHCs.

Adolescent↗
PubMed2005

Round window membrane and labyrinthine pathological changes: an overview.

The round window membrane is considered the most likely pathway from the middle to the inner ear. Various substances placed in the middle ear have been seen to pass through the round window membrane. Once toxic substances or inflammatory mediators such as cytokines and nitric oxide enter the inner ear, various inner ear sequelae such as labyrinthitis, endolymphatic hydrops, sensorineural hearing loss or more insidious diseases can occur.

Bacterial Infections↗
PubMed2005

Malignant melanoma of the auricle.

Malignant melanomas are found in a variety of locations, ranging from sun-exposed skin to the nasal cavity and paranasal sinuses. Melanomas arising in the head and neck region comprise some 20% of all melanomas; of these, 7-15% occur in the vicinity of the external ear (most often on the helix). Auricular melanomas, like those arising elsewhere, are rare in childhood and are most often first diagnosed in men in their 50s. Melanomas of the external ear may present as flat pigmented lesions or as raised mass lesions; amelanotic (non-pigmented) variants exist as well. Auricular melanomas are frequently recognized pathologically as either superficial spreading melanomas or nodular melanomas. These tumors are aggressive, with a propensity for spreading to both regional lymph nodes and distant sites. Key pathologic prognostic features of auricular melanomas include the histological subtype, tumor thickness, level of invasion and presence of ulceration. Therapy includes both aggressive surgical attempts at excision in combination with sentinel node sampling in some instances and perhaps, adjuvant therapy as well. This is a tumor which is often overlooked until late in its course, with tragic consequences; vigilance and aggressive attempts at identifying these tumors at earlier stages are strongly advocated.

Biomarkers, Tumor↗
PubMed2005

Quantitative study of the vestibular sensory epithelium in cochleosaccular dysplasia.

BACKGROUND: Cochleosaccular dysplasia is the most common pathologic finding seen in children with profound congenital sensorineural hearing loss. There has been no quantitative study on the peripheral vestibular system in cochleosaccular dysplasia. OBJECTIVE: To investigate quantitatively the extent of pathologic changes of the vestibular sensory epithelium in cochleosaccular dysplasia. SUBJECTS AND METHODS: Thirteen temporal bones with congenital deafness from 10 individuals were selected for this study from the temporal bone collection of University of Minnesota that showed suitable pathologic findings for the histopathologic criteria of cochleosaccular dysplasia. Age-matched normal control temporal bones were also selected. The vestibular hair cells including types I and II hair cells were counted separately in the saccular macula, utricular macula, and three cristae of the semicircular canals using Nomarski microscopy. RESULTS: The hair cell densities of types I and II hair cells in the macula of the saccule in cochleosaccular dysplasia were significantly decreased compared with the data of normal subjects. Both types I and II hair cells in the utricular macula and the cristae of the three semicircular canals in cochleosaccular dysplasia were well preserved, and no significant difference was observed between findings of cochleosaccular dysplasia and normal controls in the utricle and the three semicircular canals. CONCLUSIONS: In cases with cochleosaccular dysplasia, the neurosensorial hair cells of the saccule were affected; however, the osseous labyrinth, the membranous utricle, and the semicircular canals were normal. Further studies should be performed to establish the pathogenesis of cochleosaccular dysplasia in humans.

Adolescent↗
PubMed2005

Cupular deposits and aminoglycoside administration in human temporal bones.

In this study, the deposits of basophilic material on the cupula of the semicircular canals in temporal bones from patients who had aminoglycoside administration within six months prior to death were compared with normal temporal bones. Subjects were divided into two groups. Group I included 24 normal control temporal bones age-matched to group II patients. Group II consisted of 23 temporal bones that had received aminoglycosides within six months prior to death. All temporal bones were examined under light microscopy. One (4.2 per cent) of 24 temporal bones in group I (normal) showed basophilic deposits. In group II, deposits were observed in 8 (34.8 per cent) of 23 temporal bones. The prevalence of basophilic deposits in group II was significantly higher than group I. This study demonstrates that within six months after aminoglycoside administration there is an increased prevalence of basophilic deposits on the surface of the cupula. Such changes may be related to the benign paroxysmal positional vertigo (BPPV) seen in some patients who have had aminoglycoside administration.

Adolescent↗
PubMed2004

Massive endolymphatic sac and vestibular aqueduct in Mondini dysplasia.

A postmortem study was performed on the bilateral temporal bones of a 90-year-old woman who had a lifelong profound hearing impairment. The histopathologic findings included severe Mondini dysplasia with unusual enlargement of the vestibular aqueducts and endolymphatic sacs. Dehiscent carotid arteries and dehiscent facial nerves were also present. The clinical and surgical aspects of the case are discussed based on the histopathologic findings. The physician should be prepared to diagnose congenital hearing impairment promptly to avoid complications during the clinical and surgical treatment of patients with Mondini dysplasia.

Aged↗
PubMed2004

Effects of aminoglycoside administration on cochlear elements in human temporal bones.

OBJECTIVE: Although there have been numerous reports on the relationship between the period of aminoglycoside administration and cochlear damage in animals, to date there have been no such studies in humans. The purpose of this study is to observe the early and late cochlear effects of aminoglycoside administration on hair cells, spiral ganglion cells, stria vascularis, and spiral ligament. METHODS: Specimens were divided into three groups. Group I included "normal" temporal bones with no histopathologic findings of otitis media and no history of otologic or ototoxic drug administration. Group II consisted of temporal bones that received aminoglycosides within 2 weeks before death and group III of temporal bones that had aminoglycosides from 2 weeks to 6 months prior to death. Patients in groups II and III received gentamycin, kanamycin or tobramycin. Temporal bones were excluded from groups II and III if patients had a history of otologic disease or other ototoxic drugs. All temporal bones were examined under light microscopy. Standard cytocochleograms and spiral ganglion cell reconstructions were done on all temporal bones. Morphometric measurements of areas of stria vascularis were made in all turns of the cochlea on mid-modiolar sections. Spiral ligament was divided into four segments according to the locations of different types of fibrocytes. The mean loss of fibrocytes in each segment was estimated. RESULTS: The percentages of intact outer hair cells in the basal turn were significantly greater in group I compared to groups II and III. The mean area of the stria vascularis in the apical turn was significantly less in groups II and III compared to group I. CONCLUSION: This study demonstrates that in a short period (within 2 weeks) after aminoglycoside administration, a decrease in hair cells and in the area of the stria vascularis occurred.

Administration, Topical↗
PubMed2004

Cellular changes of Reissner's membrane in Meniere's disease: human temporal bone study.

OBJECTIVE: To study the cellular characteristics of Reissner's membrane (RM) in temporal bones (TBs) from patients with endolymphatic hydrops with symptoms of Meniere's disease (EH/+MD) and TBs with endolymphatic hydrops without symptoms of Meniere's disease (EH/-MD) in an effort to understand the role of endolymphatic hydrops in MD symptoms. STUDY DESIGN: Comparative study of human TB histopathology. METHODS AND MATERIALS: Epithelial and mesothelial cellularity of RM from control TBs, TBs from patients with EH/+MD, and TBs from patients with EH/-MD were compared. The cellularity of epithelial and mesothelial cell nuclei (defined as number of cells/100 microm width of RM) were counted along the width of RM. The width of RM was measured from the vestibular crest of the spiral ligament to the limbus spiralis. RESULTS: The cellular densities of epithelial cells in the basal and middle turns of RM were significantly higher in the EH/+MD and EH/-MD groups compared with "controls." There was no difference in epithelial cellularity between EH/+MD and EH/-MD. There was a decrease in the number of mesothelial cells of RM in the basal turn in EH/+MD and EH/-MD groups (statistically significant only in EH/+MD group) when compared with controls. The number of mesothelial cells of RM in the middle turn in EH/+MD and EH/-MD groups were significantly decreased compared with normals. DISCUSSION: Similar findings in cellularity of RM in temporal bones with EH/+MD and EH/-MD suggest that pathophysiologic mechanisms other than hydrops may be responsible for symptoms in Meniere's disease.

Adolescent↗