Integrating optical fiber force sensors into microforceps for ORL microsurgery

The delicate anatomy of the ear require surgeons to use great care when operating on its internal structures. One example for such an intervention is the stapedectomy, where a small crook shaped piston is placed in the oval window of the cochlea and connected to the incus through crimping thus bypassing the diseased stapes. Performing the crimp process with the correct force is necessary since loose crimps poorly transmit sound whereas tight crimps will eventually result in necrosis of the incus. Clinically, demand is high to reproducibly conduct the crimp process through a precise force measurement. For this reason, we have developed a fiber Bragg grating (FBG) integrated microforceps for use in such interventions. This device was calibrated, and tested in cadaver preparations. With this instrument we were able to measure for the first time forces involved in crimping a stapes prosthesis to the incus. We also discuss a method of attaching and actuating such forceps in conjunction with a robot currently under development in our group. Each component of this system can be used separately or combined to improve surgical accuracy, confidence and outcome.

Invasive sphenoidal aspergillosis: successful treatment with sphenoidotomy and voriconazole

Treatment of invasive sphenoidal aspergillosis is surgical, followed by antifungal therapy, mostly amphotericin B. To optimize the adjuvant antifungal treatment, which is often limited by severe side effects, the new triazole antifungal agent voriconazole with broad coverage of fungal pathogens including Aspergillus was investigated in a study of 4 patients with clinical, radiological and histological signs of invasive sphenoidal aspergillosis. They first underwent endoscopic sphenoidotomy with drainage and extraction of the fungal mass. Postoperatively, 2 patients were immediately treated with voriconazole. Two patients initially received amphotericin B; but this treatment had to be stopped because of acute renal toxicity. Finally, all patients were treated orally with 200 mg voriconazole twice a day for 12-14 weeks. After this combined treatment all patients were asymptomatic and there were no endoscopic or radiological signs of residual fungal disease. The only side effects were nausea in one and transient visual disturbances in 2 other patients. In the 4 patients presented and treated, voriconazole was shown to be effective and less toxic than amphotericin B in adjuvant treatment of invasive sphenoidal aspergillosis. Copyright (c) 2007 S. Karger AG, Basel.

Insertion of double bicanalicular silicone tubes after endonasal dacryocystorhinostomy in lacrimal canalicular stenosis: a 10-year experience

To assess the long-term results of double bicanalicular silicone tubes in canalicular (presaccal) stenosis of the nasolacrimal duct system, a retrospective follow-up was performed on patients operated between 1992 and 2002. Forty-five patients were included in the study, 44 of whom had eyes with canalicular stenosis (primary dacryocystorhinostomy), 4 with congenital agenesis of the lacrimal duct system, and 3 cases after primary external dacryocystorhinostomy. Double bicanalicular silicone tubes were inserted, fixed in the vestibulum nasi, and left in place as long-term space holders. Of the 51 endonasal primary dacryocystorhinostomies with canalicular stenosis, 32 (63%) became symptom-free after one procedure. Nineteen (37%) patients had a relapse. Double silicone bicanalicular tube insertion as long-term spacers in canalicular stenoses has a number of advantages, but canalicular stenoses still remain a challenging area.

Mastoiditis in children: a prospective, observational study comparing clinical presentation, microbiology, computed tomography, surgical findings and histology

The aim of this study was to obtain comprehensive data on clinical presentation, microbiology, computed tomography, surgical findings and histology in acute, sub-acute and chronic mastoiditis. We performed a prospective, observational study in children under 16 years of age presenting to our institution during the 2-year period beginning in April 2000. The children were examined and their condition treated in accordance with a standardized protocol elaborated by the paediatric, otolaryngology (ORL) and radiology departments. Thirty-eight patients were hospitalized (22 with acute mastoiditis, seven with sub-acute mastoiditis, nine with chronic mastoiditis). There were 30 complications present in 21 patients (55%). Streptococcus pyogenes was the most common pathogen (7/24 cases), followed by Streptococcus pneumoniae (4/24 cases). Mastoid surgery was performed in 29 patients. Histology of mastoid tissue revealed predominantly acute inflammation in two cases, mixed acute/chronic inflammation in 19 cases and predominantly chronic inflammation in seven cases. Radiologic data were evaluated retrospectively. Spiral, volume-based high-resolution (HR) computed tomography (CT) of the temporal bone had a sensitivity of 100%, specificity of 38%, positive predictive value (PPV) of 50% and negative predictive value (NPV) of 100% in detecting coalescence of mastoid trabeculae. Cranial CT with contrast had a sensitivity of 80%, specificity of 94%, PPV of 80% and NPV of 94% in identifying intra-cranial extension. Conclusion: histological evidence suggests that sub-acute/chronic infection underlies not only sub-acute and chronic mastoiditis, but most cases of acute mastoiditis as well. HR-CT of the temporal bone is effective in ruling out coalescence. Cranial CT is valuable in identifying intra-cranial extension. Cranial and HR-CT are recommended in the examination of children with mastoiditis.

Otologic manifestations in Samter's syndrome

OBJECTIVE: It was the aim of this study to investigate the prevalence of otologic manifestations in a cohort of Samter's syndrome patients (nasal polyps with chronic rhinosinusitis, aspirin intolerance and asthma). METHODS: We analyzed a retrospective and prospective case review from 1995 to 2005, performed in the otorhinolaryngology outpatient clinic of a tertiary referral center. Ear history, clinical examinations, treatment and outcome were evaluated using office and hospital records in 23 cases. All subjects completed a questionnaire. RESULTS: In 6 cases (26%), otological manifestations with ear pressure and conductive hearing loss occurred during an advanced stage of Samter's syndrome (>5 years after onset of the first nasal symptoms) partially responsive to systemic steroids. CONCLUSION: Recognition of the association between Samter's syndrome and otological disease is important (26% of the cases) because it could also be responsive to systemic steroids which prevent progression to irreversible hearing loss or infectious otomastoiditis.

Effect of hay dust extract and cyathostomin antigen stimulation on cytokine expression by PBMC in horses with recurrent airway obstruction

Equine recurrent airway obstruction (RAO) is an inflammatory, obstructive airway disease induced by exposure of susceptible horses to inhaled organic dust particles. The immunological process underlying RAO is still unclear. Previous studies have shown that RAO is linked to the Interleukin-4 receptor (IL-4R) gene in one Warmblood family (F1), but not in another (F2). It has also been shown that in F1, but not in F2, RAO is associated with resistance against parasites, suggesting that this association may have an immuno-genetic basis. Therefore, we hypothesized that the T helper (h)1/Th2/regulatory (Treg) cytokine profiles of RAO-associated antigen- and parasite-antigen-stimulated peripheral blood mononuclear cells (PBMC) differ between RAO-affected and healthy horses depending on their genetic background. In our study, PBMC from 17 RAO-affected and 14 healthy control horses of F1 and F2 were stimulated for 24h with antigens relevant to RAO [hay dust extract (HDE), Aspergillus fumigatus extract (AFE) and lipopolysaccharids (LPS)]; cyathostomin extract (CE) and recombinant cyathostomin antigen (RCA) or with concanavalin A (ConA). Total mRNA levels of IL-4, IL-4R, IL-13, interferon (INF)-γ and IL-10 were examined by qRT-PCR. Stimulation with either HDE or RCA resulted in significant differences in IL-4R mRNA levels between RAO-affected and control horses in F1, but not in F2. For IL-10 mRNA expression, a significant difference between RAO-affected and control horses in F1 but not in F2 was observed only following stimulation with HDE. In contrast to HDE, stimulation with CE resulted in a significant difference of IL-10 mRNA expression level between RAO-affected horses of F2 and healthy horses of F1. No significant differences were detected upon stimulation with any of the other challenge agents. These findings indicate that the immunological response, specifically IL-4R expression, in response to hay dust and cyathostomin antigens, differs between RAO-affected and healthy horses depending on their genetic background. This study shows that analysis of PBMC reveals systemic changes associated with RAO and helps to elucidate immunological pathways involved in this disease.