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D Simmen

Publications and source records attributed to D Simmen.

At least 19 recordsLinked to original sources
PubMed2006

The surgeon's view of the anterior ethmoid artery.

OBJECTIVES: To define the relationship of the anterior ethmoid artery to the frontal recess and secondly whether the degree of pneumatisation of the suprabullar recess/supraorbital cell correlates with the distance between the anterior ethmoid artery and the skull base thus making it more vulnerable to damage during surgery. METHOD: Thirty-four cadaver head sides were perfused with pink latex. All specimens had high-resolution computed tomography (CT) scans using bone windows in the axial, coronal and sagittal planes. The specimen's nasal septum was removed and the ethmoid sinuses dissected to locate the anterior ethmoid artery. Calipers were used to measure distance between the artery and the frontal recess and from the skull base. RESULTS: The anterior ethmoid artery was found in all the specimens and scans. The distance between the anterior ethmoid artery and the posterior wall of the frontal recess was 11 mm (range 6-15 mm). In all specimens, the artery was seen between the second and third lamella. The commonest location of the artery was in the suprabullar recess (85.3%). Supraorbital cells were seen in 16 specimens. The ethmoid sinuses were well pneumatised with a large supraorbital cell in 10 of these specimens and in these the artery was lying 3.7 mm (range 1-8 mm) away from the skull base. Six specimens had poor pneumatisation and a small supraorbital cell and in these the artery was found close to or with in the skull base. In specimens without a supraorbital cell, the artery lay at the skull base in all but one. CONCLUSIONS: The position of the anterior ethmoidal artery is very variable. The artery is found between the second and third lamella. When the ethmoid sinuses are more pneumatised and in particular when there is a supraorbital cell, the artery lies below the skull base. A good strategy is to identify the degree of pneumatisation of the ethmoid sinuses from CT scans preoperatively to see if the artery is at an increased risk of being damaged.

Arteries↗
PubMed2003

Impaired sense of smell in patients with nasal surgery.

The aim of the study was to determine the incidence of olfactory disorders before and following nasal and paranasal sinus surgery. It was a prospective observational study. Over a 6-month period, all patients who had been listed for nasal and paranasal sinus surgery underwent preoperative and postoperative evaluation of their sense of smell. A questionnaire and the 'Smell Diskettes Test' were used to assess olfaction. One hundred and eighty-four patients were studied. Preoperatively, 19 patients (10.3%) had an impaired sense of smell (8.1% before septoplasty, 6.1% before rhinoplasty and 17.1% before endoscopic sinus surgery). Only 16 (84%) of these patients were aware of their impaired sense of smell. Following surgery, four patients (2.5%) who were normal preoperatively developed impaired olfaction on questioning, and this was supported by testing it. In the subgroup that had a septoplasty, no patient developed hyposmia compared to one patient (2.6%) after rhinoplasty and one patient (3%) after endoscopic sinus surgery. No patient developed anosmia. Preoperatively, 10.3% of patients had an altered sense of smell, making it desirable that this is documented in order to avoid postoperative claims that this was caused by surgery. It also helps to audit the results of surgery.

Female↗
PubMed2002

[State of the Art. Diagnostic imaging of paranasal sinus diseases].

The following article describes a diagnostic concept of paranasal sinus imaging, based on more than 10 years close collaboration of the authors. CT and MR are the primary imaging modalities for investigating paranasal sinus lesions. Conventional X-ray images add little information due to insufficient sensitivity. Angiography is restricted to those patients who require preoperative tumor embolization or emergency treatment of intractable epistaxis. After thorough medical treatment of inflammatory paranasal sinus disease, CT becomes the method of choice to clearly depict preoperative osseous anatomy and to distinguish between benign and malignant intraosseous lesions. In cases where trauma is involved, CT easily identifies anterior skull base fractures. Moreover, CT will be the first step to localize early or late CSF rhinorrhea. MR, with its ability to distinguish between different soft tissues, compliments CT. This holds particularly true for inflammatory or neoplastic disease close to the skull base, orbital apex and cavernous sinus. The signal intensity in T(1) and T(2) weighted images provides additional information with respect to cellularity and vascularization of lesions, which has important diagnostic and therapeutic implications.

Angiography, Digital Subtraction↗
PubMed2002

Histological, immunological and molecular features of a nasal mucosa primary melanoma associated with nasal melanosis.

Nasal mucosa melanoma is a rare entity that may occur together with nasal melanosis. The histological and immunological features and loss of heterozygosity analysis of such lesions have not been reported to date. In the study presented here short-term cell cultures were established from the patient's melanoma and subsequent relapses. Histology, immunohistochemistry, reverse transcription-polymerase chain reaction enzyme-linked immunosorbent assay, human leukocyte antigen analysis, microdissection with subsequent polymerase chain reaction for analysis of loss of heterozygosity were used to characterize the tumour and other cells. Melanoma of the nasal cavity was found, with a surrounding proliferation of atypical melanocytes corresponding to nasal melanosis. Immunoreactivity was found for S-100, gp100, tyrosinase and MelanA protein. Loss of heterozygosity for a p16-flanking marker was found in the tumour and the melanotic cells. Short-term cell cultures expressed tyrosinase and MUC18 at the mRNA level and intercellular adhesion molecule-1 (ICAM-1) and interleukin-12 receptor at the protein level. This is the first time short-term cell cultures have been established and analysed from such a tumour. Melanoma-associated antigens were identified within the tumour. The melanoma and the melanotic cells showed loss of heterozygosity for the p16 gene, which is implicated in melanoma development. This points to a common origin in tumorigenesis. Pathways of tumour escape, such as expression of CD54 and interleukin-10, were observed. The clinical, immunological and molecular features suggest that nasal melanosis should be followed closely.

Adult↗
PubMed2001

Significance of human papillomavirus in sinonasal papillomas.

Recent investigations have suggested human papillomavirus (HPV) to be involved in the development of sinonasal papillomas (SNP). Forty-three patients operated for SNP were studied to determine the prevalence of HPV-DNA sequences in these tumours and to evaluate their value as a prognostic parameter. The original sections of all cases were reviewed and reclassified according to the WHO. Paraffin blocks available from 37 patients were subjected to in situ hybridization (ISH) and polymerase chain reaction (PCR). Histology revealed 34 cases of inverted papilloma (IP) (79 per cent), five cases of exophytic papilloma (EP) (12 per cent) and four cases of columnar cell papilloma (CCP) (nine per cent). Recurrences developed in seven of 41 patients (17 per cent), and malignancy occurred in four of 43 patients (nine per cent). HPV was detected in four of 37 specimens (11 per cent) both by ISH and PCR. In particular, HPV-11 was found in three lesions (two EP, one IP) (eight per cent), and HPV-6b was detected in one lesion (one EP) (three per cent). Our findings suggest a possible role for HPV in the pathogenesis of exophytic papillomas. As no correlation was found to malignancy and recurrence of disease, screening for HPV seems not to be useful as a prognostic parameter.

Humans↗
PubMed2000

Validation of excised bovine nasal mucosa as in vitro model to study drug transport and metabolic pathways in nasal epithelium.

The present work aims at the validation of excised bovine nasal mucosa as an in vitro model to address transport and metabolism pathways relative to the nasal mucosal uptake of therapeutic peptides. Preservation of the viability of the excised tissue in the course of in vitro studies of up to 3 h was demonstrated by (i) positive viability staining, (ii) constant transepithelial electrical resistance (42 +/- 12 Omega cm(2)), (iii) constant rates of metabolic turnover, and (iv) linear permeation profiles of therapeutic peptides and (3)H-mannitol. Using 1-leucine-4-methoxy-2-naphthylamide as a model substrate, we observed no difference between bovine and human nasal aminopeptidase activity. By a series of therapeutic peptides, no direct correlation was found between their effective permeability coefficients (from 0. 1 x 10(-5) to 5 x 10(-5) cm s(-1)) and their respective molecular masses (from 417 to 3,432 Da), indicating that other factors dominate nasal permeability. For instance, the permeabilities of metabolically labile peptides were concentration dependent and saturable, as demonstrated for two short thymopoietin fragments, Arg-Lys-Asp (TP3) and Arg-Lys-Asp-Val (TP4). By permeation studies using gonadorelin and two gonadorelin derivatives, buserelin and Hoe 013, without and in the presence of the chemical enhancer bacitracin, we also verified the ability of the model to assess chemical enhancer effects and their reversibility. In conclusion, our work demonstrates the potential of the investigated in vitro model, excised bovine nasal mucosa, to explore mechanistic aspects of nasal transport and metabolism of therapeutic peptides.

Absorption↗
PubMed2000

[Significance of human papillomaviruses (HPV) in sinonasal papillomas].

The present study comprises 43 patients with sinonasal papillomas operated on between 1990 and 1997 at the ENT Department, University Hospital of Zurich. Histology showed 5 cases of exophytic papilloma (EP) (12%), 34 cases of inverted papilloma (IP) (79%) including 4 cases of associated carcinoma (9%), and 4 cases of columnar cell papilloma (CCP) (9%). Recurrence developed in 6 of 41 patients (2 EP, 4 IP) (15%). HPV was detected in 4 of 37 specimens (11%) both by in situ hybridization (ISH) and polymerase chain reaction (PCR). HPV-11 was found in 3 lesions (2 EP, 1 IP), whereas HPV-6b was detected only in one lesion (1 EP). Altogether 3 of 5 EP (60%), one of 29 IP (3%) and one of 6 recurrent papillomas (1 EP) (17%) tested positive for HPV. Our findings suggest a possible role for HPV in the pathogenesis of exophytic papilloma. As no correlation was found with associated malignancy and recurrence of disease, screening for HPV seems not to be useful as a prognostic parameter.

Cell Transformation, Neoplastic↗
PubMed1999

A dynamic and direct visualization model for the study of nasal airflow.

OBJECTIVE: To evaluate nasal airflow characteristics during physiologic breathing in normal and pathologic conditions. DESIGN: The choana of an anatomical human model was connected to a pump that simulated physiological pressure changes in the upper airway system. Normal ambient air was used as medium. The airstream was marked with aerosolized water particles, and was observed through an exact but translucent replica of the original nasal septum. RESULTS: In physiologic conditions the airflow is mixed. Turbulence is clearly visible even with low flow velocities. There is less turbulence with lower flow rates. The nasal airflow follows a triphasic pattern of acceleration, near-steady state, and deceleration. Turbulence is prominent in the first and third phases. The main flow stream passes through the middle meatus at all rates. Hypertrophic mucosal membranes and turbinates increase the proportion of air passing the middle meatus. With decongested turbinates, flow distribution is more even. After turbinectomy there is a significant amount of airflow passing along the floor of the nose. The olfactory region is aerated only toward the end of inspiration and during the entire expiration phase. CONCLUSIONS: This model allows the investigation of airflow distribution and turbulence under physiologic conditions and the examination of the influence of pathologic conditions on these parameters. Overzealous trimming of turbinates results in an unphysiologic distribution of airflow.

Airway Resistance↗
PubMed1999

[Screening of olfaction with smell diskettes].

BACKGROUND: Aim of the study was the development of a new screening test of olfaction with reusable diskettes as odorant applicators. METHODS: A screening test of olfaction was designed using 8 diskettes containing different odorants. The diskettes can be opened to release the odor and are closed after testing. The test was designed as a triple forced multiple choice test using a questionnaire, resulting in a score from 0 to 8 correct answers. Ninety-one volunteers with a normal sense of smell and 13 patients with subjective hyposmia or anosmia were tested to validate the developed test. The same volunteers were also tested with the sniffin' sticks test, another screening test of olfaction that is already validated. After testing, the volunteers were asked to compare the two tests. RESULTS: Among the 91 volunteers with normal sense of smell, 10 achieved a score of 7, and 81 a score of 8 in the smell disk test. The 13 patients with hyposmia or anosmia achieved a score between 0 and 5. Based on the test design, there is a probability of 99.74% that a person who achieves a score of 7 or 8 will have normal olfaction. In the sniffin' sticks test, 85 volunteers with normal sense of smell achieved a score in the normal range for this test (6-8) whereas 6 volunteers were below with a score of 4 or 5. The 13 patients with hyposmia or anosmia scored between 0 and 6. The smell disk test was preferred by 86 persons, the sniffin' sticks test by 5, and 12 assessed both tests as equal. CONCLUSIONS: The developed screening test is reliable for identifying patients with a normal sense of smell, and it can distinguish them from patients with hyposmia and anosmia. The diskettes proved to be reliable and comfortable applicators for odorants in clinical practice.

Adolescent↗
PubMed1999

Smell diskettes as screening test of olfaction.

A screening test of olfaction was developed with reusable diskettes as applicators of 8 different odorants. Using a questionnaire with illustrations, the test was designed as a triple forced multiple choice test resulting in a score of 0 to 8 correct answers. To validate the test, 102 volunteers with normal olfaction, as well as 22 patients with subjective hyposmia or anosmia, were tested. To compare the developed test with an already validated method, the same persons also performed the sniffin' sticks screening test. The results indicate that the screening test with smell diskettes recognizes patients with normal olfaction and consistently distinguishes them from patients with hyposmia or anosmia.

Adolescent↗
PubMed1998

[Epistaxis strategy--experiences with the last 360 hospitalizations].

BACKGROUND: The purpose of this study was to analyze the therapy concept used in the management of severe epistaxis in order to optimize the quality of our treatment and to arrive at an optimal therapeutic concept. MATERIAL AND METHODS: The study was performed as a retrospective analysis of the charts of all 335 patients treated as inpatients for epistaxis over a period of 6 years. RESULTS: An increased rate of complications was found in the following three situations: 1. Age > 65 years, 2. chronic obstructive pulmonary disease, 3. several systemic illnesses. Recurrence was increased with septal perforations and Osler's disease. CONCLUSIONS: Localization of the site of bleeding is the first priority and allows treatment of bleeding with bipolar electrocautery. If the bleeding vessel is not found, insertion of a Merocel pack is recommended. Patients with persistent or recurrent bleeding are treated in the operating theater under general anesthesia if they are at an elevated risk for complications or have a septal deviation which is clinically significant. The nose is systematically visualized with the endoscope, bleeding vessels are coagulated under endoscopic control, and, where appropriate, a septoplasty is performed. In the remaining cases an epipharynx balloon is inserted, combined with an anterior pack. Angiography with superselective embolization, external ligation of the ethmoidal arteries, and endonasal obliteration of the sphenopalatine artery is reserved for cases where the measures discussed above have failed.

Adult↗
PubMed1998

[Rhinosurgical concept in management of fronto-basal defects with cerebrospinal rhinorrhea].

BACKGROUND: Cerebrospinal fluid (CSF) leak, with its potential infectious complications remains today a challenge in diagnosis and surgical treatment. With the introduction of endonasal microsurgery, new minimally invasive techniques for the repair of these defects have been pioneered. Nasal approaches to the anterior skull base include external-transfacial as well as endonasal approaches for reconstruction. It is important to have multiple possible approaches for the correction so that the optimal method for the individual pathology may be selected. The purpose of this paper is to clarify the decision process for selecting the safest procedure with the least possible morbidity and functional compromise. METHOD: In a retrospective study we assessed a group of 69 patients treated from 1988 to 1996. Patient records, CT scans, postoperative clinical follow-up and a questionnaire, sent to the patients, were evaluated. The various external and endonasal approaches are presented and the closure techniques are discussed in detail. RESULTS: Of the 69 operations, 40 (58%) were external and 29 (42%) were endonasal. There were three failures in the external approach group (4.4%) and no failures in the endonasal group. No major complications in the intraoperative or postoperative course occurred. Of importance, olfaction was retained in 94% of patients in at least one side. The average duration of hospitalization was 6 days. CONCLUSIONS: Nasal approaches to the anterior skull base for treatment of CSF leaks are highly effective, safe, and cause minimal morbidity. The optimal surgical approach is chosen according to the precise location and extent of the defect. We are now increasing using endonasal microsurgical approaches. The open, transfacial approaches are still indicated for fractures of the posterior wall of the frontal sinus as well as larger multi-fragmented fractures of the anterior skull base.

Adolescent↗
PubMed1998

[Nasal fractures--indications for open reposition].

BACKGROUND: Many septoplasties and septorhinoplasties are indicated due to previous traumatic etiologies, and the typical treatment of these septal and/or bone fractures has been closed reduction. Review of the literature reveals a success rate of only between 30-82%. One of the reasons for these poor outcomes is the influence of tension and pressure stress vectors due to hidden cartilage fractures behind intact septal mucosa. This is the main indication for open reduction of nasal trauma. The present study analyses the results of our experience with the open reduction of nasal fractures. METHODS: In a six-year period between 1991 and 1996, a total of 34 open reductions were performed out of 155 nasal fractures. This series was analysed clinically and with the aid of computer tomograms. Postoperative follow-up involved a combination of clinical evaluation, nasal endoscopy, and photography. The indication for open reposition was based on analysis of force of impact and suspicion of cartilage damage. The goal of the procedures was to incise partial-thickness fractures to make them full-thickness, thereby relieving the inherent tension in the cartilage, and to mobilize impacted bone fragments with microosteotomies so they could be properly reduced. At the same time, any previously existing anatomical abnormalities with functional impact were also corrected. RESULTS: The rate of patient satisfaction based on postoperative cosmesis and function was 88%. The group in which open reduction was most commonly indicated was the frontal impact cohort (n = 18.53% of open reductions). This was followed by the frontolateral impact cohort (n = 8.23%). In only one (1/155) open reduction was it not possible to find a cartilage fracture on exploration. Revision surgery was required in 2 cases due to nasal obstruction from synechiae between the septum and the anterior aspect of the inferior turbinate. Reoperation was necessary in a third patient due to airway obstruction from septal deviation. In a final case the patient was dissatisfied with the postoperative nasal appearance but declined revision surgery. Analysis of computer tomograms gave no additional information, though three-dimensional CT can aid in preoperative assessment of fragment position in those cases with severe edema and hematoma. CONCLUSION: Due to the high rate of subjective and objective success in postoperative nasal function and appearance, we suggest that consideration be given to widening the current indications for open reduction of nasal fractures. It is important to maintain a high degree of suspicion and explore the septum for subclinical fractures and be aware of the pattern of damage that can be anticipated based on classification of impact as described herein. The importance of precise clinical evaluation by inspection, palpation, and endoscopy cannot be overemphasized, and may not be replaced by radiographic imaging.

Adolescent↗
PubMed1998

[Chronic mycoses of the paranasal sinuses--value of endonasal paranasal sinus surgery].

BACKGROUND: Many host factors even in immunocompetent patients may have an influence on development of a fungal diseases within the paranasal sinuses. Fungal sinusitis can occur in an acute form or more often to a chronic type of the disease. These mainly relatively asymptomatic chronic forms and further divided into a chronic noninvasive, chronic allergic, and chronic invasive disease. Endonasal microsurgery has significantly changed the management of chronic fungal sinusitis and allows adequate removal of pathologic tissue even in advanced situations. The aim of this study was to analyze the efficacy of endonasal surgery in chronic fungal sinusitis. MATERIAL AND METHODS: In a retrospective study we assessed a group of 40 patients who had endonasal surgery for chronic fungal sinusitis. Patient records, CT and MRI scans, microbiology and histology as well as the postoperative clinical follow-up including endoscopic photo documentation were evaluated over a period of 5 years. All patients underwent endonasal surgery using endoscopic techniques. The microscopic was of additional help in a few cases with extended disease and multiple dehiscences of the skull base. RESULTS: Twenty-four patients had a chronic noninvasive of fungal sinusitis and 16 patients had a chronic invasive form. All these patients underwent endonasal surgery without external incision. The fungal disease was erradicated in 39 cases, and revision surgery was required in only one case in which involvement of the contralateral side was not initially detected. in two cases scar tissue in the middle meatus was later excised but without evidence of residual fungal disease. Only in 6 cases was antifungal chemotherapy required, where the disease had spread into surrounding tissue or the patient had severe symptoms. CONCLUSIONS: Endonasal microsurgical techniques are today the appropriate approach for managing chronic fungal sinus disease even in severe cases with radiologic evidence of expansion or invasion of surrounding tissue. Additional antifungal chemotherapy is only rarely indicated, specifically when the fungal disease invades surrounding tissue.

Adult↗
PubMed1998

Tributary venosinus occlusion and septic cavernous sinus thrombosis: CT and MR findings.

PURPOSE: In autopsy reports of patients who died of septic cavernous sinus thrombosis, tributary venosinus occlusion has been a common finding related to intracranial inflammatory complications. The purpose of this article is to illustrate the MR and CT appearance of septic cavernous sinus thrombosis and tributary venous occlusion. METHODS: Over a period of 7 years, eight patients with septic cavernous sinus thrombosis were examined by contrast-enhanced thin-section CT. The CT scans of these eight patients and those of 30 healthy control subjects were assessed independently and subjectively by two blinded readers to ascertain the presence, size, and density of areas of nonopacification within the cavernous sinus and the presence of filling defects and dilation of tributary veins and venous sinuses. In six subjects, MR images supplemented by a contrast-enhanced spoiled gradient-recalled acquisition in the steady state (SPGR) sequence were assessed with respect to the presence of filling defects, expansion, and signal abnormalities within the cavernous sinus and tributary veins and sinuses. The MR and CT findings were compared. RESULTS: The CT studies of the eight patients were consistently differentiated from those of the control subjects by the two readers. Contrast-enhanced CT findings in patients included areas of nonopacification that were present within the cavernous sinus bilaterally in six cases and unilaterally in two. The size of the filling defects exceeded 7 mm in 76% of thrombosed cavernous sinuses compared with 9% of control subjects. The mean density of filling defects in patients differed significantly from those in control subjects. Comparison of the MR and CT findings in six cases showed the contrast-enhanced SPGR sequence to be equivalent to CT with respect to delineation of filling defects. CONCLUSION: Contrast-enhanced high-resolution CT findings indicate that venosinus thrombosis associated with septic cavernous sinus thrombosis is not restricted to the superior ophthalmic vein and is more common than previously assumed. A contrast-enhanced SPGR MR sequence may be used as a reliable alternative to establish the diagnosis of cavernous sinus and tributary venosinus thrombosis.

Adolescent↗
PubMed1997

Revolutionary inventions in the 20th century. The history of endoscopy.

Today, the wide variety of modern endoscopes allows routine diagnostic examinations. Precise observation is possible because of excellent optical and light transmission. Surgery can be performed while viewing a television screen, and video documentation and intraoperative photography are possible with outstanding quality. The invention of a rod-lens optical system by Harold H. Hopkins, PhD, in 1959 and the addition of fiberoptic light transmission by Karl Storz in 1960 marked a breakthrough in modern endoscopy. This article summarizes an interview with the instrument maker, Karl Storz.

Endoscopes↗
PubMed1997

[Computerized tomography of paranasal sinuses--a preoperative check list].

BACKGROUND: Computed tomography (CT) is being used increasingly both to evaluate location and extent of sinus disease and to detect anatomic abnormalities prior to surgery. Analysis of the CT scan should be undertaken in a routine, standardized fashion to ensure that important details are not missed. To aid in this evaluation, a checklist has been developed which focuses on the most salient and potentially dangerous areas of the paranasal sinuses. Regular preoperative analysis using this system may prevent unforeseen technical difficulties and excess morbidity. MATERIALS AND METHODS: Before obtaining a CT scan, the patient is placed on optimal medical therapy including antibiotics, and topical and occasionally systemic steroids. Coronal scans are then performed with 3 mm sections through the frontal and sphenoid sinuses and 2 mm sections through the ethmoid region. Intravenous contrast is used. The study is then analyzed focusing on specific critical anatomic landmarks. When additional information is required due to severe pathology or atypical anatomy, axial sections are added. RESULTS: Out of 300 CT examinations that where analyzed, a preoperative checklist was developed with eight items that must be evaluated preoperatively. Methods for the identification and analysis of this anatomy as well as the types of anatomic variation are discussed. We have found this evaluation to be extremely useful and efficacious in preventing morbidity in endoscopic sinus surgery. CONCLUSIONS: Evaluation of the preoperative CT examination with a strictly applied checklist of important details and landmarks allows the recognition of hazardous anatomy and pathology which should increase the safety and efficacy of paranasal sinus surgery.

Chronic Disease↗