Tympanometric changes in an experimental myringosclerosis model after myringotomy.

HYPOTHESIS: The goal of this experimental study was to investigate the specific effect of myringosclerosis on tympanograms in the tympanic membranes of myringotomized rats by using otomicroscopy, tympanometry, and histopathology. BACKGROUND: Myringosclerosis is a common sequela of ventilation tube treatment of otitis media with effusion. The condition involves the hyalinization and calcification of the collagen layer in certain areas of the tympanic membrane. Previous animal experiments suggest an intimate relationship between the formation of myringosclerosis and an increased oxygen concentration in the environment of the wound after myringotomy. The result of a myringotomy therefore is an increased production of free oxygen radicals, initiating irreversible tissue damage involving fibrosis, hyalin degeneration, and finally apoptosis as observed in myringosclerosis. We propose an experimental model specific for creating sclerotic plaques solely on the tympanic membrane and for performing tympanometric measurements on this pure myringosclerosis model without creating any abnormality in the middle ear to test in what proportion myringosclerosis contributes to decrease of amplitude in tympanograms. METHODS: To assess the normal tympanometric values of Wistar albino rats, the pressure and peak admittance of the left middle ears were measured using a semiquantitative computerized clinical admittance meter using a sound frequency of 226 Hz. Twelve animals were randomly selected for the myringotomy group and perforations in the left ears were created. All tympanic membrane perforations in this group had healed and closed prior to the otomicroscopic examination and no pathologic reaction was observed in the external ear canals of rats. Otomicroscopic and tympanometric measurements were carried out on Day 15 and the degree of myringosclerosis was noted before the animals were killed. Twelve specimens in the myringotomy group were histopathologically examined for the presence of myringosclerotic plaques. RESULTS: Under light microscopy, extensive sclerotic lesions were found in the tympanic membranes of the myringotomy group, and these sclerotic deposits were located in the lamina propria. The myringosclerosis occurred predominantly adjacent to the handle of the malleus, but also near the annular region. In all ears with myringosclerosis, the magnitude of the maximum admittance reduced to approximately 50% of the Day-0 values, and this reduction was statistically significant (Z=-3.061, p=0.002). CONCLUSION: The present findings in this study are consistent with the fact that the movement of the tympanic membrane is hampered by lesions of sclerotic material, resulting in a decrease of amplitude in tympanograms (such as Type As) without any effusion or inflammation in the middle ear.     

Disorganization of the retinal inner layers as a prognostic factor in eyes with central retinal artery occlusion

AIM: To evaluate baseline foveal disorganisation of retinal inner layers (DRIL) as a prognostic factor in eyes with central retinal artery occlusion (CRAO). METHODS: Twenty-eight CRAO patients who were followed-up between 2010 and 2016 were retrospectively investigated. Demographic characteristics and detailed ophthalmological examination findings of all patients were recorded. Macular thicknesses (MTs) from 5 separate spots and DRIL were measured with spectral-domain optic coherence tomography (SD-OCT). Correlations between DRIL score and logMAR converted visual acuity (VA), change in VA, patient reference time (RT), number of hyperbaric oxygen therapy (HBOT) sessions, MT and MT change were investigated. RESULTS: There was a positive correlation between the DRIL score and the final VA (r=0.787) and a negative correlation with the change in VA (r=-0.763). The RT and MT were closely related to the DRIL score. A negative correlation was found between the number of HBOT sessions and the DRIL score (r=-0.341). CONCLUSION: The DRIL score is a parameter assessed by SD-OCT, which can provide us reliable information regarding the prognosis of visual functions and response to the treatment for CRAO patients at acute phase.     

Anatomie des Felsenbeins

The petrous portion of the temporal bone is an important location of traumatic injuries as well as inflammatory and neoplastic diseases in the clinical daily routine. In addition to the articles in this issue that focus on these diseases, this article provides a short overview of the clinically relevant anatomy of the petrous portion of the temporal bone.     

Neonatal Outcomes of Pregnancy with Immune Thrombocytopenia

Neonates born to mothers with immune thrombocytopenia (ITP) have an increased risk for neonatal thrombocytopenia and hemorrhagic complications. The aim of this study was to determine the maternal and neonatal outcomes of pregnancies with ITP and also to identify risk factors that predicts neonatal thrombocytopenia. We performed a retrospective analysis of 40 pregnancies with ITP and their 40 neonates. Among the 40 neonates, thrombocytopenia (platelet count of less than 150 × 10⁹/L) was detected in 15 neonates (37.5 %) whom 8 of them had severe thrombocytopenia (platelet count of less than 50 × 10⁹/L). Ten of the 15 neonates with thrombocytopenia required treatment to increase the platelet counts. There was statistically significant association between neonatal thrombocytopenia and maternal splenectomy history and maternal duration of thrombocytopenia. There was no statistically significant correlation between maternal platelet count and neonatal platelet count. Clinicians should pay special attention in these neonates because of risk for development of neonatal thrombocytopenia. Maternal and neonatal outcomes in patients with idiopathic thrombocytopenic purpura is generally good.     

Comparison of the Torsional Resistance of 4 Different Glide Path Instruments

IntroductionThe present study aimed to compare the torsional strength of the initial files of the Mtwo (VDW, Munich, Germany) and novel Rotate systems (VDW, Munich, Germany) with the ProGlider (Dentsply Sirona, Ballaigues, Switzerland) and R-Pilot (VDW) glide path instruments.MethodsThe Mtwo (10/.04), ProGlider (16/.02), R-Pilot (12.5/.04), and Rotate (15/.04) glide path files were compared regarding their torsional strength, which was tested using a specially designed test device (N = 20). The data obtained were statistically analyzed at 5% significance level using 1-way analysis of variance and the post hoc Tukey test. The fragment surfaces and separated instruments were examined with ×50, ×100, and ×1000 magnification under a scanning electron microscope.ResultsThe R-Pilot group showed the highest torsional strength value among all groups (P < .05), whereas there was no significant difference between the torsional strength values of the Mtwo and ProGlider groups (P > .05). The Rotate group had the lowest torsional strength among all groups (P < .05). The Mtwo group showed the lowest angle of rotation among all groups (P < .05).ConclusionsAlthough the R-Pilot glide path file exhibited the highest torsional strength in all groups, Rotate showed the highest angle of rotation. Differences in torsional resistance of the instruments may be associated with their manufacturing methods and design features.     

Lumbar spinal stenosis in a young individual as a result of ligamantum flavum ossification: A case report

INTRODUCTIONSymtomatic lumbar ligamantum flavum calcification is quite rare in the young age group.PRESENTATION OF CASEThe authors report a case of young adult with diagnosis of lumbar spinal stenosis, presenting with leg pain and neurological deficits. Computerized tomography (CT) scan and magnetic resonance (MR) imaging studies revealed ossification of the ligamantum flavum as the causative factor of the disease and the patient recovered completely after the decompressive operation.DISCUSSIONIt is emphasized that attention should be given to this rare etiological factor of lumbar spinal stenosis.CONCLUSIONComplete relief can be achieved with early and adequate surgery.