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Biomedical subjects

L Klimek

Publications and source records attributed to L Klimek.

At least 73 records · Page 4Linked to original sources

Three-dimensional ultrasound evaluation in the head and neck.

We evaluated the use of a novel three-dimensional ultrasound imaging device in patients with various head and neck lesions. The investigated system was found to be a valuable adjunct to conventional ultrasound in head and neck evaluations. A disadvantage of the three-dimensional system was the need for expensive technical equipment.

Head and Neck Neoplasms↗

[Computer-assisted surgery in the ENT specialty. Developments and experiences from the first decade].

BACKGROUND: Computer-Assisted-Surgery (CAS) names a method that allows intraoperative navigation in the surgical field based on digital image data like CT, MRT, MRA, DSA and others. A computer processes the image data in real time and is intraoperatively connected to a measuring system for coordinate determination. CAS is used in ENT surgery since 1986. The authors developed several generations of CAS systems. METHODS: In a first approach, a passive robot arm was applied. Self-developed electromechanical and infrared optical coordinate measuring devices followed. RESULTS: CAS was applied to several fields of otorhinolaryngologic surgery including the paranasal sinuses, the orbit, the rhinobasis and otobasis and other. CAS was found to be useful for surgery of acoustic neuromas, the paranasal sinuses in cases of massive disease or revision surgery, decompression of orbit or optiv nerve, extraction of deep seated foreign bodies, stereotaxy-like biopsies, for educational purposes and others. CONCLUSIONS: CAS in its current state of development is a useful tool that can be routinely applied. However, further technical development is necessary.

Computer Systems↗

Lateralized and bilateral olfactory function in patients with chronic sinusitis compared with healthy control subjects.

Results of this study demonstrated that a new olfactory test, the "Sniffin' Sticks," can be used to distinguish hyposmic patients with chronic sinusitis (n = 63) from control subjects. Dirhinic testing yielded improved olfactory sensitivity compared with monorhinic testing. However, dirhinic results were not significantly different from results obtained for the best nostril.

Adolescent↗

Comparison of olfactory function in patients with seasonal and perennial allergic rhinitis.

Hyposmia is a common symptom in allergic rhinitis. However, little is known about differences in the olfactory function of patients with seasonal or perennial allergy. A prospective controlled study was performed on 28 patients with allergic rhinitis to grass pollen and on 47 patients with allergic rhinitis to mites. Sixty-six healthy volunteers served as a control. Olfactory function was evaluated by a modified Connecticut Chemosensory Clinical Research Center testing procedure for threshold, identification, and discrimination. The grass pollen-allergic patients were tested preseasonally and after 3 weeks of intraseasonal grass pollen exposure; the mite-allergic patients and the volunteers were tested once. In the mite allergics, olfactory threshold, identification, and discrimination tests were significantly worse than in the volunteers (all P < 0.0001). In the grass pollen allergics, the results in olfactory identification and discrimination tests were not different from the controls if tested out of the season (both P > 0.05). However, in threshold testing (P = 0.0139), the results were worse. Intraseasonally, the grass pollen allergics showed a significant decrease in threshold, identification (both P < 0.0001), and discrimination testing (P = 0.0029). If the intraseasonal pollen allergics were compared to the mite allergics, they showed better results in identification (P = 0.0087) and threshold (P < 0.0001) tests, but worse results in discrimination testing (P = 0.0002). Therefore, the different kind of allergen exposure seems to result in a different pattern of allergic olfactory dysfunction.

Adolescent↗

Tree-pollen allergy is efficiently treated by short-term immunotherapy (STI) with seven preseasonal injections of molecular standardized allergens.

The efficacy and tolerance of short-term immunotherapy (STI) by seven preseasonal injections of tree-pollen allergens (ALK7 Frühblühermischung) was investigated in a double-blind, placebo-controlled, multicenter study with 111 rhinoconjunctivitis patients. Nasal and bronchial symptoms simultaneously analyzed, and nasal symptoms as a single end point, but not the overall score of nasal, bronchial, and conjunctival symptoms, showed a significantly lower increase with STI during birch-pollen exposure (both P=0.033, n=105, Mann-Whitney U-test). However, a selective analysis with patients from centers with high recruitment figures (n> or =10 patients, n=29 STI, n=32 placebo) showed a significantly lower increase of nasal, bronchial, and overall symptom score (STI 11.0 vs placebo 18.0, P=0.001, U-test). STI had equidirected effects on conjunctival, nasal, and bronchial symptoms analyzed as multiple end points, although conjunctival symptoms were not significantly different as a single end point. The seasonal increase in drug use was reduced by 62% in the STI group compared with placebo (P=0.032, t-test). Specific IgG4 increased only after STI (P<0.001); IgE was not significantly different. Eosinophil cationic protein remained unchanged with STI, but significantly increased with placebo in the pollen season (P=0.003). STI was well tolerated. In conclusion, STI was shown to be efficacious and safe for the treatment of patients with tree-pollen rhinoconjunctivitis.

Adolescent↗

[Sense of smell in allergic rhinitis].

BACKGROUND: Olfactory dysfunction is one of the major complaints in patients suffering from allergic rhinitis. Little is known about the onset of hyposmia in seasonal allergy. METHODS: We performed two prospective studies to examine olfactory function in allergic rhinitis using an established (modified CCCRC) test for olfactory threshold, identification and discrimination. RESULTS: In a pilot study the time-course of olfactory function in 14 patients with allergic rhinitis to grass pollen was examined at the beginning of the season. Olfactory function was evaluated birhinal on day 3, 7, 14, and 21 of the season. Preseasonally, all patients were normosmic. There was a significant decrease in threshold and identification between the third and fourteenth day of the season, resulting in a moderate hyposmia in the mean. Hyposmia was not correlated to subjective symptom of nasal blockage. Therefore, a follow-up study was performed on 17 patients and a control group with a similar study design including measurements of nasal volume flow (rhinomanometry) and an inflammatory cell activation marker (ECP) in nasal secretions. The time-course of the olfactory changes was much better correlated to the inflammatory measure than to nasal volume flow. CONCLUSIONS: Patients with allergic rhinitis develop a significant olfactory dysfunction under allergen exposition. Inflammatory dysfunction of the olfactory epithelium seems to be more important than respiratory dysfunction in the pathomechanism of allergic hyposmia.

Adult↗

[Endoscope-microscope combination (ENDO-OPMI) for endonasal paranasal sinus surgery].

The development of modern endonasal sinus surgery is fundamentally based on the introduction of optical instrumentation. Endoscopes and microscopes are commonly used in such surgery. We tested a new combination of a stereoscopic single-channel endoscope with an operating microscope (ENDO-OPMI) for endonasal sinus surgery. This combination of the endoscope and microscope are connected in a way that results in a self-carried stereo-endoscope. To date, the ENDO-OPMI has been evaluated in cadaver studies and 7 cases of endonasal sinus surgery for chronic sinusitis. The trial was used to evaluate the clinical use of the current system and its possibilities for future developments. The ENDO-OPMI was demonstrated to be principally well-suited for endonasal sinus surgery. However, the current technical shortcomings make further developments necessary. Once these are implemented, the system should be superior to the use of an endoscope or microscope alone in endonasal surgery.

Chronic Disease↗

Olfactory dysfunction in allergic rhinitis is related to nasal eosinophilic inflammation.

BACKGROUND: Olfactory dysfunction is a common finding in patients suffering from allergic rhinitis. However, little is known about the pathophysiology underlying this phenomenon and about the time course of hyposmia in seasonal allergy. METHODS: A prospective controlled study was performed on 17 patients with allergic rhinitis to grass pollen in order to evaluate olfactory function in correlation to the duration of allergen exposition, symptoms, eosinophil cationic protein (ECP) in nasal secretions, and nasal volume flow (NVF). Olfactory function was evaluated preseasonally and on days 3, 7, 14, and 21 of the season using a modified Connecticut Chemosensory Clinical Research Center testing procedure for threshold, identification, and discrimination. Twelve volunteers without allergy served as controls. RESULTS: Preseasonally, patients and controls performed equally in discrimination and identification testing, but not in threshold testing. No changes were found in the controls, but a significant decrease in threshold and identification from the 7th day of the season in patients with allergy was noted that was better correlated to ECP than to NVF. NVF was already maximally decreased from the 3rd intraseasonal day with no further changes. ECP increase became significant at day 14. CONCLUSION: Patients with grass pollen allergy develop olfactory dysfunction during natural allergen exposure that might be related to allergic inflammatory mechanisms.

Adult↗

[Reproducibility and seasonal dependence of specific intranasal provocation tests in birch pollen allergy patients].

BACKGROUND: The intranasal allergen Provocation test (INT) is the standard procedure to verify the effect of an allergen when a nasal allergy is suspected. It may be especially useful if results from skin tests or in vitro tests conflict with those from the history. In the clinical and research setting, INT may be used to study the efficacy of different treatment modalities such as pharmacotherapy or immunotherapy. The technique of INT has not been well standardized in the past. Variations exist in planning the optimum time for testing, especially in seasonal allergies. METHODS: We examined influences of different test dates with regard to the pollen season on the result of INT. A total of 19 patients (eight females, 11 males, aged 26.1 +/- 4.8 years) with a history of at least two years of allergic rhinitis to birch pollen, positive skin prick test, and RAST (> or = CAP class II) to birch pollen. INT was performed during the winter-period after approximately six months without natural pollen exposition (V1), during the birch pollen season (V2) and six weeks after the birch pollen season (V3). Allergens were applied using a pump spray (0.1 ml) in concentrations of 10, 50, 100, 500, 1000, 5000, 10,000, 50,000, and 100,000 SQ units per ml (SQ/ml). RESULTS: The threshold concentrations were significantly lower at V2 (100 SQ/ml) and V3 (500 SQ/ml) if compared to V1 (1000 SQ/ ml). CONCLUSIONS: Seasonal influences should be taken into account when performing INT in birch pollen allergy.

Adolescent↗

Heterogeneity in the polyclonal T cell response to birch pollen allergens.

BACKGROUND: Immunodominant epitopes of Bet v 1a had been identified before, using recombinant (r) Bet v 1a-reactive T cell clones generated from peripheral blood mononuclear cells of patients allergic to birch pollen. This study aimed at evaluating the T cell-stimulating capacity of immunodominant Bet v 1a-derived peptides in a polyclonal system corresponding more closely to the situation in patients. METHODS: Short-term T cell lines (TCL) were established in presence of a protein extract of birch pollen (BP extract). TCL proliferation induced by the BP extract, by natural Bet v 1, rBet v 1a, rBet v 2 or 5 selected immunodominant Bet v 1a-derived peptides was determined. RESULTS: Consistent with the knowledge that Bet v 1 is the major IgE-binding allergen of birch pollen, we found comparable T cell reactivity to natural Bet v 1 and the BP extract within the majority of the TCL. Accordingly, the response to rBet v 2 was low compared with the reactivity to the BP extract. The response of the TCL to rBet v 1a proved to be highly heterogeneous. Furthermore, the TCL response to the 5 immunodominant Bet v 1a-derived peptides showed considerable diversity. The proliferative responses of most TCL (with one exception) following stimulation by these peptides were low, in relation to the expansion induced by the BP extract. CONCLUSION: These findings argue against the use of selected peptides derived from Bet v 1a in specific immunotherapy of patients with birch allergy.

Allergens↗

Endoscopic surgery of the rhinobasis with a computer-assisted localizer.

The endoscope is useful for the diagnosis and surgical therapy of diseases of the nose, the paranasal sinuses and its neighboring regions, and allows for microinvasive, functional approaches. The reduced invasiveness of therapeutic procedures is sometimes accompanied by insufficient clearness of the surgical field, however. This significant problem is solved by the computer-assisted-surgery (CAS) system, an intraoperative localizer. It allows continuous orientation based on three-dimensional reconstructed preoperative CT scans with superimposed positioning of the endoscope. We have now adapted CAS for endoscopic sinus surgery, which meant that a variety of visualization methods were tested. A conventional straightforward endoscope was used in combination with, or as, the localizing probe. A dual-display technique was adjusted to video-endoscopic procedures: the information of the localizer is displayed on one monitor while the video-endoscopic picture is viewed on a second screen. In addition, a single-display technique with both images on one monitor was developed. It proved to be the most promising way of combining endoscopy and intraoperative CT-image-guided localization.

Endoscopes↗

[Cell activation markers in rhinitis and rhinosinusitis. 1: Eosinophilic cationic protein (ECP)].

BACKGROUND: The quantitative analysis of the migration and activation of inflammatory cells is standard in current diagnosis of inflammatory diseases of the nasal mucosa. Histological and cytological examinations are mostly used for this purpose. Development and validation of assays for specific marker proteins of the different cell populations make similar analyses possible from nasal secretion samples. Myeloperoxidase (MPO) or Elastase are important markers for neutrophil granulocytes as is Tryptase for mast cells, Lysozyme for macrophages/monocytes and Eosinophil Cationic Protein (ECP). Eosinophil Neurotoxin/Eosinophil Protein X (EDN/EPX) or Major Basic Protein (MBP) for eosinophil granulocytes. METHODS: We performed a prospective study on healthy volunteers and patients with different inflammatory nasal and paranasal sinus diseases and analysed such cell activation markers in nasal secretions. In the healthy volunteers, 183 nasal secretion samples were obtained. A total of 515 samples were obtained in patients with the diagnosis: chronic sinusitis (n = 49), allergic rhinitis to perennial allergens (n = 94), chronic sinusitis with additional allergic rhinitis to perennial allergens (n = 36), nasal polyps (n = 28), allergic rhinitis to seasonal allergens extraseasonally (n = 131), and allergic rhinitis to seasonal allergens during the pollen season (n = 177). RESULTS: In part I of this paper we describe the results for the Eosinophil Cationic Protein (ECP). In all patients with active inflammatory reactions significantly higher ECP levels than in the controls were found. Moreover, ECP levels differed between the diseases investigated. CONCLUSIONS: ECP nasal secretion level seem to be a valuable marker for the assessment of nasal eosinophilic inflammation and might become an adjunct to current diagnostic measures.

Adult↗

Sedation in allergic rhinitis is caused by the condition and not by antihistamine treatment.

Sedation is regarded as a common side-effect of most H1-antihistamines. This view must be accepted, yet can hardly be assessed under treatment of allergic disorders. Since central sedative potency is hard to evaluate, different methods of measurement have been introduced in the four phases of clinical investigation. While tests of high complexity in early trials can detect true central effects, they seem to have the disadvantage of not taking into consideration the important interactions of drugs with the disorder. Therefore, we used a visual analog scale (VAS) as an instrument to demonstrate sedative effects in five clinical studies carried out between 1989 and 1994 with a total number of 1070 patients. Thereby, we could assess the result of the different components of the central interaction. In 1989, in a double-blind, placebo-controlled trial, we could show that the vigilance of patients suffering from seasonal allergic rhinitis increased significantly more under treatment with an antihistamine (mizolastine) than under placebo. From 1992 until 1994, we compared azelastine nasal spray either by the double-dummy technique with oral antihistamines (cetirizine, loratadine, and astemizole) or by the double-dummy or placebo-controlled design with monotherapy or combined therapy with azelastine tablets. A marked or statistically significant improvement of vigilance was found for all compounds (loratadine: P < 0.0001; cetirizine: P < 0.0254; and azelastine nasal spray: P < 0.1409 to P < 0.0001). Even when taking azelastine as oral application, patients, in spite of the warning, reported a similar increase in vigilance (P < 0.2628 to P < 0.0001). Finally, we assessed the range of physiologic vigilance using the same VAS in healthy volunteers. In conclusion, we could prove that in all trials the baseline values of vigilance of untreated symptomatic patients were far below physiologic condition and improved under treatment to the upper range of healthy persons. Therefore, any sedative properties of modern H1-antihistamines should not limit their therapeutic use, since the truly threatening sedation results from the disorder itself.

Arousal↗

Increased in vitro cysteinyl leukotriene release from blood leukocytes in patients with asthma, nasal polyps, and aspirin intolerance.

In vitro cysteinyl leukotriene (cLT) release from blood leukocytes was measured in eight normal individuals (NI), nine patients with nasal polyps (NP) without aspirin intolerance, and eight patients with NP, asthma, and aspirin intolerance (AI). Blood leukocytes were prestimulated with interleukin-3 (IL-3) and incubated with acetylsalicylic acid (ASA) (10 and 100 micrograms/ml) together with C5a (10(-8) mol/l) for 18 h. cLT release (LTC4, LTD4 and LTE4) from blood leukocytes was measured with a competitive enzyme-linked immunoassay. Background cLT release was 259 +/- 66 pg/ml (mean +/- SEM) in the NI group, 185 +/- 33 pg/ml in the NP group, and 578 +/- 136 pg/ml in the AI group (P = 0.1). After incubation with 10 micrograms/ml ASA, cLT concentration was lower in normal subjects (346 +/- 72 pg/ml) and in patients with NP (209 +/- 53) than in patients with AI (686 +/- 75 pg/ml, P = 0.002). After incubation with 100 micrograms/ml ASA, cLT concentrations were 285 +/- 72 pg/ml in the NI group, 313 +/- 77 pg/ml in the NP group, and 654 +/- 121 pg/ml in the AI group (P = 0.04), respectively. Simultaneous incubation with ASA 10 micrograms/ml and C5a (10(-8)mol/l) resulted in a cLT concentration of 751 +/- 171 pg/ml in the NI group, 343 +/- 102 pg/ml in the NP group, and 2196 +/- 480 pg/ml in patients with AI (P = 0.0006), whereas simultaneous incubation with ASA 100 g/ml and C5a (10(-8)mol/l) resulted in 268 +/- 51 pg/ml in the NI group, 412 +/- 97 pg/ml in the NP group, and 1701 +/- 368 pg/ml in the AI group (P = 0.005). In patients with AI, cLT release from blood leukocytes is altered when compared with normals and patients with NP. The presented cLT-release assay could be of potential use in the in vitro diagnosis of AI.

Adult↗

Computer-assisted image-guided surgery in pediatric skull-base procedures.

Skull-base surgery is characterized by the variety of important neural and vascular structures within a narrow operating field. Although preoperative imaging by computed tomography (CT) and magnetic resonance imaging (MRI) and the use of microsurgical techniques have improved intraoperative orientation, a large number of complications still are caused by localization problems. Especially in pediatric skull-base surgery, maximum localization accuracy during surgery is required. The authors developed a localizing system based on tomographic imaging (such as CT or MRI) to achieve safer surgery by providing highly accurate location information. The preliminary successful experience in the use of the Aachen computer-assisted surgery device for pediatric skull-base surgery (14 cases) is presented. Indication include juvenile angiofibroma of the nasopharynx, infectious and tumorous diseases of the paranasal sinuses, orbital tumors, foreign bodies, and intracranial abscess formation.

Adolescent↗