Risk factors for occurrence and progression of external auditory canal cholesteatoma.

OBJECTIVE: External auditory canal cholesteatoma (EACC) is characterized by retained squamous debris within the external canal and variable amounts of localized bone destruction. The etiology of primary EACC remains incompletely understood. This study was conducted to analyze the clinical features and backgrounds of patients with primary EACC and to clarify the risk factors for the occurrence and progression of EACC. METHODS: Sixty-nine ears of 62 patients diagnosed with primary EACC were included in this study (EACC group). Additionally, 74 ears of 60 patients with chronic otitis media (COM) with perforation who underwent tympanoplasty or myringoplasty were included as controls (COM group). We retrospectively investigated the clinical features, life history, and medical history of the patients in both groups. In addition, to investigate the risk factors for progression of EACC, we compared the clinical features and medical history of patients with stage IV (advanced) disease versus stage I + II (mild) disease. RESULTS: The inferior wall of the bony canal was the main structure affected in patients with primary EACC of all stages. The following factors were significantly more common in the EACC than COM group: older age, female sex, left-sided disease, osteoporosis, renal dysfunction, anemia, and treatment with bisphosphonates. Among these, the most significant factor associated with EACC was renal dysfunction (odds ratio, 11.4; 95 % confidence interval, 2.32-55.9). The significant factors observed in patients with stage IV disease were younger age, male sex, posterior wall involvement, and otorrhea. Surgical treatment was required for more than half of the patients with stage III and IV EACC. CONCLUSION: Patients with renal dysfunction are at risk of primary EACC. In particular, younger patients and relatively younger elderly patients with posterior wall involvement have a risk of progression to advanced-stage EACC. Canalplasty should be considered in patients with EACC who have these risk factors to prevent progression to advanced-stage disease.

Clinical characteristics of atelectatic eardrums and adhesive otitis media in children.

OBJECTIVES: Atelectatic eardrum and adhesive otitis media in children are related to persistent otitis media with effusion (OME) and eustachian tube dysfunction in infancy. However, the pathogenesis of these diseases is not fully understood, and some cases even progress to pars tensa cholesteatoma. This study analyzed the clinical characteristics of children with atelectatic eardrum and adhesive otitis media to clarify associated causes of and risk factors for progression of these middle ear pathologies in children. PATIENTS AND METHODS: This retroactive study included 38 ears of 31 children with atelectatic eardrums (atelectasis group), and 19 ears of 17 children with adhesive otitis media (adhesive OM group). Thirty-two contralateral non-cholesteatoma ears of 32 children with congenital cholesteatoma were also examined as a control group. Participants were aged 15 or younger. Life history (obtained via questionnaire), associated diseases, hearing acuity, aeration and development of the temporal bone were investigated. RESULTS: All children in the atelectasis and adhesive OM groups had a history of recurrent acute otitis media (rAOM) and/or OME. The prevalence of perennial allergic rhinitis was 18 cases (58%) in the atelectasis group and 16 cases (94%) in the adhesive OM group. The prevalence of perennial allergic rhinitis was significantly higher in the adhesive OM group compared to the control group (P < 0.01). The development of mastoid air cells, categorized by MC classification, showed MC0 + MC1 (poor pneumatization) in 19 ears (50.0%) with atelectatic eardrums and 12 ears (63.2%) with adhesive OM. Poor pneumatized mastoid was more frequently observed in the ears of the atelectasis and adhesive OM groups compared to the control group (P < 0.01). No significant difference was found in regards to aeration of the middle ear between the two groups; however, aeration was significantly poorer in both groups compared to the control group (P < 0.01). Three characteristics were analyzed using multivariate logistic regression: perennial allergic rhinitis (odds ratio [OR] 4.319, P = 0.013), poor mastoid pneumatization (OR 8.457, P = 0.012), and pars flaccida retraction pocket (OR 20.897, P = 0.006). These characteristics were shown to be significant risk factors for atelectatic eardrums and adhesive OM. In addition, the predisposition to perennial allergic rhinitis was shown to be the most important factor in the progression from atelectatic eardrum to adhesive otitis media (OR 16.615, P = 0.012). CONCLUSION: Children with perennial allergic rhinitis, poor development of mastoid air cells, poor aeration of the temporal bone, and with pars flaccida retraction pocket were at an increased risk of developing an atelectatic eardrum and adhesive OM. In particular, perennial allergic rhinitis was shown to be a significant risk factor in the progression from atelectatic eardrum to adhesive otitis media. Allergic inflammation may affect not only the nasal passages but also the eustachian tube, resulting in persistent middle ear dysfunction. Therefore, children with rAOM/OME who have these risk factors should be carefully monitored and treat over time in effort to prevent progression of pathology.

Comparative study on adhesive otitis media and pars tensa cholesteatoma in children.

OBJECTIVE: Recurrent otitis media and persistent otitis media with effusion in early childhood may cause an atelectatic eardrum and adhesive otitis media, which sometimes progress to pars tensa cholesteatoma. When and how children with adhesive otitis media should be operated on remain controversial. Therefore, this study aimed to analyze the clinical characteristics of children with adhesive otitis media and pars tensa cholesteatoma, and to determine the risk factors of progression to cholesteatoma. METHODS: Seventeen ears of 15 children with adhesive otitis media (adhesive group) and 14 ears of 13 children with pars tensa cholesteatoma (tensa cholesteatoma group) who underwent tympanoplasty were included in this study. We analyzed the following clinical characteristics of children in both groups: medical and life history, associated diseases, sites of the adhesion, and development and aeration of mastoid air cells as shown by temporal bone computed tomography. RESULTS: Most of the children in both groups had a history of recurrent otitis media and/or persistent otitis media with effusion. They showed a male predominance and a frequent association of allergic rhinitis. The number of ears showing undeveloped mastoid air cells in the tensa cholesteatoma group was significantly larger than that in the adhesive otitis media group (P=0.0068). A lack of aeration of the middle ear, including the eustachian tube, was more frequently found in ears with pars tensa cholesteatoma than in ears with adhesive otitis media (P=0.0012). Using multivariate logistic regression, the presence of otorrhea (odds ratio [OR], 14.847; 95% confidence interval [CI], 0.834-264.184), total adhesion (OR, 28.550; 95% CI, 0.962-847.508), and undeveloped mastoid air cells (OR, 19.357; 95% CI, 1.022-366.589) were related to pars tensa cholesteatoma. CONCLUSION: Children with adhesive otitis media should be carefully followed up in the outpatient setting. Ears with poor mastoid development may develop pars tensa cholesteatoma. Additionally, ears with middle ear effusion, total adhesion, and the presence of otorrhea tend to be at risk of pars tensa cholesteatoma. Tympanoplasty or tympanostomy tube insertion should be considered for children with adhesive otitis media who have these risk factors to prevent progression to pars tensa cholesteatoma.

Corneal Graft Rejection after Descemet's Membrane Endothelial Keratoplasty with Peripheral Anterior Synechiae.

Descemet's membrane endothelial keratoplasty (DMEK) for patients with corneal endothelial loss rarely results in graft rejection. Herein, we report a rare case of graft rejection following DMEK, in which peripheral anterior synechiae were observed postoperatively. A 66-year-old woman was referred to our hospital after complaints of decreased visual acuity of her right eye after laser iridotomy for primary angle closure 3 years earlier. Her right cornea had bullous keratopathy with mild cataract, and her best-corrected visual acuity (BCVA) was 20/40. After cataract surgery, DMEK was successfully performed, except for development of peripheral anterior synechiae at the temporal cornea. Her BCVA recovered to 20/20. However, when topical instillation was changed to 0.1% fluorometholone from 0.1% betamethasone once a day, corneal edema reappeared with hyperemia, mutton fat keratic precipitates (KPs), and cells in the anterior chamber. The BCVA worsened to 20/32. Graft rejection was diagnosed, and subconjunctival injection of dexamethasone was performed 3 times, once every few days, with 0.1% topical betamethasone instillation. Subsequently, the hyperemia, mutton fat KPs, and cells in the anterior chamber disappeared with a recovered BCVA of 20/20 after 2 weeks. Ten months after graft rejection, there was no recurrence of intraocular inflammation, and only topical betamethasone was administered twice daily. It is important to exercise caution in cases with peripheral anterior synechiae after DMEK. Long-term steroid administration is necessary to prevent graft rejection.

Efficient and convenient heterogeneous palladium-catalyzed regioselective deuteration at the benzylic position.

The Pd/C-catalyzed efficient and regioselective hydrogen-deuterium (H-D) exchange reaction on the benzylic site proceeded in D2O in the presence of a small amount of H2 gas. The use of the Pd/C-ethylenediamine complex [Pd/C(en)] as a catalyst instead of Pd/C led to the efficient deuterium incorporation into the benzylic site of O-benzyl protective groups without hydrogenolysis. These H-D exchange reactions provide a post synthetic and D(2)-gas-free deuterium-labeling method on a wide variety of benzylic sites using D2O as the deuterium source and heterogeneous Pd/C or Pd/C(en) as a reusable heterogeneous palladium catalyst under mild and neutral conditions.