Klaus Jahnke

Post-tonsillectomy haemorrhage : A retrospective comparison of abscess- and elective tonsillectomy

Conclusion. There is no increased risk of postoperative haemorrhage for abscess tonsillectomies in comparison to elective tonsillectomies. Objective. There is still controversy as regards the optimal management of peritonsillar abscess. Opponents of tonsillectomy à chaud cite an increased postoperative bleeding risk. Most authors who compared the risks of postoperative haemorrhage after tonsillectomy à chaud and tonsillectomy à froid did not take into consideration criteria such as the age and gender of the patients or the experience of the surgeon. We aimed to eliminate this bias by performing a retrospective study in which a large series of abscess tonsillectomies were compared with an age- and gender-matched group of elective tonsillectomies. Material and methods. All patients had been operated on at the Department of Otorhinolaryngology, University of Duisburg-Essen between March 1994 and August 2000. There were 350 patients in the abscess tonsillectomy group (61% male, 39% female; mean age 31.8 years; range 3–88 years) and 311 in the elective tonsillectomy comparison group (61% male, 39% female; mean age 30.0 years; range 2–83 years). Results. In the abscess tonsillectomy group, 9 patients (2.6%; confidence level 1.1–4.8%) had postoperative haemorrhages which required treatment under general anaesthesia, compared to 17 (5.5%; confidence level 3.2–8.6%) in the age- and gender-matched group of “selected” elective tonsillectomies. The difference between these two rates was not significant (p=0.056). The fairly high rate of haemorrhages in the elective tonsillectomy group was mainly due to the effect of the age-matching procedure, which excluded a considerable number of usually unproblematic tonsillectomies for tonsillar hyperplasia in young children. Moreover, our results show that there is a learning curve for surgeons performing tonsillectomies with regard to postoperative haemorrhages.

Infections with Human Rhinovirus Induce the Formation of Distinct Functional Membrane Domains

The plasma membrane contains distinct domains that are characterized by a high concentration of sphingolipids and cholesterol. These membrane microdomains also referred to as rafts, seem to be intimately involved in transmembranous signaling and often initiate interactions of pathogens and the host cell membranes. Here, we investigated the further reorganization of membrane rafts in cultured epithelial cells and ex vivo isolated nasal cells after infection with rhinoviruses. We demonstrate the formation of ceramide-enriched membrane platforms and large glycosphingolipid-enriched membrane domains and the co-localization of fluorochrome-labeled rhinoviruses with these membrane domains during attachment and uptake of human rhinovirus. Destruction of glycosphingolipid-enriched membrane domains blocked infection of human cells with rhinovirus. Furthermore, our studies indicate that the activation of the acid sphingomyelinase (ASM) is intrigued in the formation of ceramide- or GM1- enriched membrane platforms. Inhibition of the ASM reduces the number of ceramide-enriched platforms and glycosphingolipid-enriched membrane domains. These data reveal a critical role of the ASM for the formation of membrane platforms and infection of human cells with rhinoviruses.

Type III tympanoplasty applying the palisade cartilage technique: a study of 61 cases.

Objective To determine the morphologic and hearing results of the combined application of the palisade cartilage technique and titanium ossicular replacement prostheses in Type III tympanoplasty. Study Design Retrospective review of 61 tympanoplasties. Setting Tertiary referral center. Patients 59 patients (39 women and 20 men, mean age 36 years, range 7–81 years) consecutively operated on because of cholesteatoma, adhesive otitis, chronic otitis media, subtotal tympanic membrane defects, and tympanofibrosis requiring tympanoplasty with ossiculoplasty. Interventions Tympanoplasty Type III, with application of the palisade cartilage technique and total or partial titanium ossicular replacement prosthesis. Main Outcome Measures Otoscopic findings and hearing results using a four-frequency pure tone average air-bone gap. Results A recurrent defect was seen in 1 ear (1.6%). The graft take rate was 100%. There were no extrusions of prostheses. Preoperatively, a pure tone average air-bone gap of 0 to 10 dB was seen in 1 ear, 11 to 30 dB in 30, and 31 to 50 dB in another 30 ears. Postoperatively, the corresponding numbers were 11, 41, and 9 ears, respectively. Hearing results were better in the total ossicular replacement prosthesis group. Conclusions The palisade cartilage technique is suitable to manage difficult pathologic conditions in middle ear surgery. It was demonstrated that the palisade cartilage technique can be combined safely with titanium ossicular replacement prostheses. Regarding postoperative hearing results, the negative preselection of pathologic conditions must be considered.

Prototype of a silicon nitride ceramic-based miniplate osteofixation system for the midface

OBJECTIVE: The favorable properties of silicon nitride (Si3N4) ceramics, such as high mean strength level and fracture toughness, suggest biomedical use as an implant material. Minor reservations about the biocompatibility of Si3N4 ceramics were cleared up by previous in vitro and in vivo investigations. STUDY DESIGN AND SETTING: A Si3N4 prototype mini-fixation system was manufactured and implanted for osteosynthesis of artificial frontal bone defects in 3 minipigs. After 3 months, histological sections, computed tomography (CT) scans, and magnetic resonance imaging (MRI) scans were obtained. Finite element modeling (FEM) was used to simulate stresses and strains on Si3N4 miniplates and screws to calculate survival probabilities. RESULTS: Si3N4 miniplates and screws showed satisfying intraoperative workability. There was no implant loss, displacement, or fracture. Bone healing was complete in all animals. The formation of new bone was observed in direct contact to the implants. The implants showed no artifacts on CT and MRI scanning. FEM simulation confirmed the mechanical reliability of the screws, whereas simulated plate geometries regarding pullout forces at maximum load showed limited safety in a bending situation. CONCLUSIONS: Si3N4 ceramics show a good biocompatibility outcome both in vitro and in vivo. In ENT surgery, this ceramic may serve as a biomaterial for osteosynthesis (eg, of the midface including reconstruction the floor of the orbit and the skull base). To our knowledge, this is the first introduction of a ceramic-based miniplate-osteofixation system. Advantages compared with titanium are no risk of implantation to bone with mucosal attachment, no need for explantation, and no interference with radiologic imaging. Disadvantages include the impossibility of individual bending of the miniplates.

Overall and relapse-free survival in oropharyngeal and hypopharyngeal squamous cell carcinoma are associated with genotypes of T393C polymorphism of the GNAS1 gene.

Purpose: In previous studies, we have shown that the T allele of a specific single-nucleotide polymorphism (SNP) in the Gαs gene (T393C) correlates with increased Gαs expression and hence apoptosis. The T allele was associated with a favorable outcome in a variety of human cancers, e.g., carcinoma of the urinary bladder, kidney, and colorectum. Experimental Design: The prognostic value of the T393C SNP was evaluated in an unselected series of patients treated with curative intent for oropharyngeal and hypopharyngeal squamous cell carcinomas, including all tumor stages with different therapeutic regimens. Genotype analysis was done using DNA from paraffin-embedded tissue samples from 202 patients (162 men, 40 women) with a median follow-up of 38 months (1-133 months). The various genotypes were correlated with relapse-free and overall survival. Results:GNAS1 393C homozygous patients displayed a higher risk for disease progression than T393 homozygous patients (hazard ratio CC versus TT, 1.9; 95% confidence interval, 1.1-3.2; P = 0.019). The same genotype effect was observed for overall survival with CC genotypes at higher risk for death compared with TT genotypes (hazard ratio, 1.7; 95% confidence interval, 1.1-2.9; P = 0.015). Multivariate analysis showed that, besides American Joint Committee on Cancer stage, tumor localization, and gender, the T393C polymorphism was an independent prognostic factor for disease progression and death. Conclusion: The T393C SNP could be considered as a genetic marker to predict the clinical course of patients suffering from oropharyngeal and hypopharyngeal cancer.

The GNAS1 T393C polymorphism predicts survival in patients with advanced squamous cell carcinoma of the larynx.

Objectives/Hypothesis: In previous studies, we have demonstrated that the T‐allele of a specific single nucleotide polymorphism (SNP) in the Gαs gene (T393C) correlates with increased Gαs expression and hence apoptosis. The T‐allele was associated with a favorable outcome in a variety of human cancers, for example, carcinoma of the urinary bladder, kidney, colorectal, oro‐ and hypopharynx.

Immunohistochemical evidence of BMP-2, -4 and -7 activity in otospongiosis.

Conclusion. This study is the first to show that bone morphogenetic proteins (BMP)-2, -4 and -7 play a role in active phase otosclerotic bone remodelling (otospongiosis). Objectives. The role of BMPs in various tissue growth and repair mechanisms is an ongoing topic in the literature. BMP-2, -4 and -7 are known to be of major importance in bone formation and repair. Their role in otosclerotic bone transformation has not been analysed previously. The main goal of this study was to perform an immunohistological analysis of BMP-2, -4 and -7 in otoclerosis. Materials and methods. Parts of the stapedial footplates, collected during partial stapedectomies in 30 patients with clinical otosclerosis, were analysed for histological otosclerotic lesions after staining haematoxylin and eosin. Immunohistochemical analysis was performed using polyclonal IgG antibodies for BMP-2, -4 and -7, as well as biotinylated secondary antibodies, avidin-biotin-peroxidase complex reaction and alkaline phosphatase staining. Results. In all, 14 specimens contained otosclerosis; 3 of these were otospongiotic, 8 fibrotic, 2 sclerotic and 1 had both sclerotic and fibrotic lesions. Thus in total 14/30 specimens (47%) showed histological otosclerosis. Only the multiple osteoblasts and osteoclasts in those specimens exhibiting an otospongiotic phase showed distinct immunochemical staining for BMP-2, -4 and -7.

Association Study of the G-Protein β3 Subunit C825T Polymorphism with Disease Progression an Overall Survival in Patients with Head and Neck Squamous Cell Carcinoma

The T-allele of a common C825T single nucleotide polymorphism (SNP) in the gene GNB3, encoding the G3 subunit of heterotrimeric G-proteins, is associated with a truncated form of the G3 protein that imparts a greater signaling capacity than the alternative C-allele encoding a nontruncated protein. We analyzed the C825T-allele status with regard to disease progression in patients with head and neck squamous cell carcinoma (HNSCC). The prognostic value of the SNP was evaluated in an unselected series of 341 patients treated with curative intent for HNSCC including all tumor stages with different therapeutic regimens. Genotype analysis was done by Pyrosequencing using DNA from paraffin-embedded tissue samples. Genotypes were correlated with relapse-free and overall survival. Proportions of 5-year relapse-free intervals were 62% for CC, 60% for TC, and 42% for TT genotypes. Kaplan-Meier curves revealed a significant genotype-dependent relapse-free interval (P = 0.036). In multivariate analysis with stage, localization, grade, gender, and smoking habits as covariates, GNB3 825T homozygous patients displayed a higher risk for relapse than C825 homozygous patients (TT versus CC, hazard ratio; 95% confidence interval, 1.4-4.8; P = 0.002). The same genotype effect was found for overall survival, TT genotypes were at higher risk for death compared with CC genotypes (hazard ratio, 2.6; 95% confidence interval, 1.6-4.3; P < 0.001), and 5-year survival proportions were 60% for CC, 52% for TC, and 33% for TT. The GNB3 C825T SNP thus represents a host derived prognostic marker in HNSCC, which allows identifying high-risk patients, which could benefit from novel and/or more aggressive therapeutic regimes. (Cancer Epidemiol Biomarkers Prev 2008;17(11):3203–7)

Signaling by way of type IB and II bone morphogenetic protein receptors regulates bone formation in otospongiosis.

Hypothesis: The main goal of this study was to perform an immunohistologic analysis of bone morphogenetic protein receptors (BMPR) in otospongiosis.

Bilateral peritonsillar abscesses

In the discussion about the management of the peritonsillar abscess (PTA) in regard to the pros and cons of tonsillectomy à chaud versus à froid, the risk of obscure contralateral abscesses is often neglected. To the authors’ knowledge, there are only a few series of PTA being analyzed for the abscess rate of bilateral PTA. A group of 541 abscess tonsillectomies was retrospectively analyzed for the presence of a bilateral manifestation of peritonsillar abscess. Twenty-one patients (3.88%) had bilateral abscesses. None of these had been detected prior to the operation. Of the 541 patients, 2.22% had postoperative hemorrhages that had to be arrested under general anesthesia. Within the discussion about abscess tonsillectomy versus stab incision followed by interval tonsillectomy (à froid), the rate of almost 4% bilateral abscesses should be taken into consideration as dangerous complications such as mediastinitis could develop from the remaining abscess formation of the contralateral side.