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Biomedical subjects

A Leunig

Publications and source records attributed to A Leunig.

At least 37 records · Page 2Linked to original sources
PubMed2001

Fluorescence staining of oral cancer using a topical application of 5-aminolevulinic acid: fluorescence microscopic studies.

INTRODUCTION: Topical application of 5-aminolevulinic acid (5-ALA) by means of a rinsing solution has been shown to be a promising new procedure in the diagnosis of oral malignancies. However, for assessing the reliability of this method regarding fluorescence-guided tumor resections and photodynamic therapy, further information on the distribution and penetration depth of 5-ALA-induced protoporphyrin IX (PPIX) in the tissue is needed. METHODS: 24 patients suffering from oral cancer were included in this investigation. Biopsies were taken immediately after fluorescence examination and either used as native sections for immediate fluorescence microscopic examination (n = 3) or shock frozen in liquid nitrogen and prepared as frozen sections (n = 46). Fluorescence imaging and digital image processing were utilized in order to determine the presence of PPIX in regions of various histologies as well as the penetration depth of PPIX into solid tumor. RESULTS: PPIX fluorescence in the tissue was limited to the epithelium. Both normal and dysplastic epithelium showed PPIX fluorescence. In the stroma, no PPIX fluorescence was found. In some cases (n = 3/4) invasive carcinomas did not show PPIX fluorescence, while the adjacent or overlying normal epithelium was strongly fluorescent. The penetration depth of PPIX after topical application of 5-ALA was found to be limited to less than 1 mm. CONCLUSION: PPIX fluorescence induced by topical application of 5-ALA can be very useful in the determination of superficial tumor margins. However, due to the limited penetration depth there is a risk of not accurately recognizing the infiltration depth of solid tumors. The aim of further investigations will be to assess the tissue distribution and depth of penetration of PPIX following systemic application of 5-ALA.

Aminolevulinic Acid↗
PubMed2001

Nasopharyngeal epignathus causing nasal airway blocking in a 4-year old child.

Congenital oral teratoma or epignathus is a very rare lesion, especially in older children. We report on a 4-year old female infant presenting with nasal blocking, little watery discharge and recurrent otitis. First adenoids were suspected. An endoscopic examination of the nose and nasopharynx demonstrated an irregular mass in the nasopharynx, covered partly by mucosa. A MRI-scan (T1-weighted) showed fat-intensity. Histological examination revealed a teratomatous malformation. Although rare, teratoma should be included in the differential diagnosis of a nasopharyngeal mass in the paediatric age group.

Child, Preschool↗
PubMed2000

Diode laser treatment of hyperplastic inferior nasal turbinates.

UNLABELLED: Background and Objective Different laser types have been used for the treatment of hyperplastic inferior nasal turbinates. The clinical experiences of its treatment by means of a diode laser are presented. Study Design/Materials and Methods A total of 76 patients suffering from nasal obstruction due to hyperplastic inferior nasal turbinates were treated with a continuous diode laser (wavelength of lambda = 940 nm, laser parameter 10 W/energy/turbinate 5 kJ) in "noncontact" mode and under local anesthesia. All patients were refractory to conservative medical treatment. Fifty patients (26 of 50 [52%] with allergic rhinitis and 24 of 50 [48%] with vasomotor rhinitis) were included into this clinical trial with a follow-up of 1 year. The study was conducted by a questionnaire, photo documentation, allergy test, mucociliary clearance test, rhinomanometry, acoustic rhinometry, conventional radiology of the paranasal sinuses, and histology. RESULTS: The mean operation time took 6 min/turbinate, no nasal packing was necessary and no immediate complications (e.g., major bleeding) were observed. During the first 2-4 weeks, nasal obstruction was correlated to the extent of postoperative edema and nasal crusting. Statistical analysis revealed significant improvement of the nasal airflow (rhinomanometry) and nasal cavity volume (acoustic rhinometry) 6 months and 1 year after laser surgery, respectively. A total of 86% of the patients described a subjective improvement of nasal airflow 6 months and 76% of the patients 1 year after laser treatment. The mucociliary function test showed no significant variation in comparison to the preoperative measurements 1 year after laser treatment. CONCLUSION: Diode laser treatment of hyperplastic inferior nasal turbinates is a useful procedure, which can be performed as an outpatient surgery under local anesthesia, resulting in a controlled coagulation and ablation of the soft tissue. The short operation time and the good results provide an excellent patient acceptance.

Adolescent↗
PubMed2000

[Highly malignant T-cell non-Hodgkin lymphoma (nasal type) of the hard palate].

The monomorphic clinical aspect of destructive mid-face lesions is characterised by inflammation, induration and granulomatous transformation. This feature can be caused by various infections, toxical noxa, Wegener's Granulomatosis and different neoplasms. The case of a 19 year old patient with EBV associated nasal type T-cell lymphoma located at the hard palate is presented. The diagnostic approach and difficulties in diagnosing this entity assessing by using multiple biopsies, serological and molecularbiological detection of EBV association and immunohistochemistry for atypic T-cells are elucidated. In the presented case the treatment with chemotherapy and irradiation following a well-defined therapy concept leaded to a three year recurrence-free survival so far. The comparison of the key-histological findings and the major differential diagnoses is mandatory to establish the final diagnosis of lymphoma. This is the basement for treating this disease with combined chemotherapy and irradiation for optimizing survival.

Adult↗
PubMed2000

Initial experience in the treatment of oral leukoplakia with high-dose vitamin A and follow-up 5-aminolevulinic acid induced protoporphyrin IX fluorescence.

The aim of photodynamic diagnostics is complete visualization of all neoplastic lesions in a tumorous organ after the application of a tumor-selective photosensitizer. We explored the potential benefit of a combination of retinyl palmitate for the treatment of oral leukoplakias and follow-up diagnosis of malignant tissue by using 5-aminolevulinic acid (5-ALA) as a fluorescence marker. Semiquantitative measurements were performed following the topical application of 5-ALA in six patients. After biopsy and histological evaluation of tissue specimens the patients were treated with escalating doses of retinyl palmitate. After treatment periods ranging from 4 to 8 weeks 5-ALA was again applied for photodetection of persisting fluorescence. In all cases prior to retinyl palmitate treatment a prominent red fluorescence indicated tissue dysplasia. Eight weeks after treatment with retinyl palmitate decreased red fluorescence intensities were found, and repeated histological evaluations showed no persistent signs of dysplastic lesions. Our initial experience shows that high doses of retinyl palmitate can be useful for treating dysplastic lesions in the upper aerodigestive tract and can be monitored with 5-ALA induced protoporphyrin IX fluorescence.

Adult↗
PubMed2000

Detection of squamous cell carcinoma of the oral cavity by imaging 5-aminolevulinic acid-induced protoporphyrin IX fluorescence.

OBJECTIVES: Early cancer detection is the best way to improve the prognosis of patients with oral cancer. Therefore this study presents quantitative fluorescence measurements and results in the visualization of cancerous oral mucosa with 5-aminolevulinic acid (5-ALA)-induced protoporphyrin IX (PPIX). METHODS: Time progression and type of porphyrin accumulation were analyzed in neoplastic and surrounding healthy tissue of 58 patients with a suspected cancer of the oral cavity by measuring emission spectra of 5-ALA-induced PPIX fluorescence. Fluorescence images in the red and green spectral range from the tumor tissue were recorded with a charge-coupled device camera. RESULTS: After topical application of 0.4% 5-ALA and incubation for 1 to 2.5 hours, all patients revealed higher intensities of red fluorescence in neoplastic tissue compared with the surrounding normal tissue. Maximum contrast was reached after 1.5 hours of incubation. In 13.8% (n = 8) of the patients, additional findings like dysplasia, carcinoma in situ, primary tumor, secondary carcinomas, and tumor branches were found by means of fluorescence marking in contrast to white light examination. An evaluation of the biopsy specimens resulted in a specificity of 60% and a sensitivity of 99%. CONCLUSIONS: As a fluorescent marker, PPIX could represent a possible new diagnostic tool to detect early malignant and secondary lesions in the oral cavity. In addition, 5-ALA-induced PPIX fluorescence is promising as a useful intraoperative tool for determining adequate surgical margins of resection. Further investigations aim to assess this diagnostic procedure as a sensitive and clinically reliable method for patients with oral cancer.

Adult↗
PubMed1999

[Polyposis nasi--effective treatment without operation? Broad etiological spectrum, individual therapy].

Various factors are thought to be involved in the etiology and pathogenesis of nasal polyps. The clinical symptoms include nasal obstruction, hyposmia or anosmia and recurrent sinusitis. At the cellular level eosinophilic granulocytes appear to have an important role to play, the growth, differentiation and degranulation of which is apparently controlled by interleukin 5. In the present study, practically relevant aspects of the pathophysiology, diagnosis, treatment and diagnostic differentiation of the various types of polyps are discussed, with the latter point also being examined for its importance with regard to therapeutic consequences.

Diagnosis, Differential↗
PubMed1999

Autofluorescence imaging and spectroscopy of normal and malignant mucosa in patients with head and neck cancer.

BACKGROUND AND OBJECTIVE: An early detection of oral cancer might improve the patient's prognosis. We present preliminary results of autofluorescence photodetection of cancerous oral mucosa. MATERIALS AND METHODS: 49 patients were investigated altogether. In 30 patients, malignant and healthy oral mucosa were excited with violet light (lambda = 375 to 440 nm). Images were recorded by a sensitive CCD camera. Spectrophotometric analysis in the green spectral range was performed on tumorous and innocuous mucosa in 36 patients. RESULTS: In 13 patients (43.3%), tumors were subjectively better distinguishable from their surroundings through a reduction of green autofluorescence than by ordinary inspection. Tumor detection abilities varied for different locations and tumor morphologies. Spectral analysis showed contrasts in autofluorescence intensities between tumor and normal tissues in 34 patients (94.4%). Autofluorescence spectra of normal mucosa varied both inter- and intraindividually. CONCLUSIONS: Using violet excitation light, camera-based autofluorescence photodetection in the green spectral range presented a highly promising tool for the diagnosis of oral malignomas in almost half of the cases examined. The possible ways on how the obtained results could serve to find a more advanced method for a precise tumor detection in the oral cavity are being discussed.

Adult↗
PubMed1999

Fluorescence staining of laryngeal neoplasms after topical application of 5-aminolevulinic acid: preliminary results.

BACKGROUND AND OBJECTIVE: The prognosis of patients suffering from laryngeal carcinomas can be improved by early diagnosis. Exact demarcation of tumor margins could contribute to an optimum preservation of the larynx. Therefore, the aim of the present study was the evaluation of 5-aminolevulinic acid (5-ALA)-induced protoporphyrin IX (PPIX) fluorescence as a new diagnostic procedure for the detection of laryngeal cancer. STUDY DESIGN/MATERIALS AND METHODS: Sixteen patients with suspected malignancies of the larynx received 0.6 wt% 5-ALA-NaCl solution by means of a medical nebulizer. After a period of 1-2 hours, the patients underwent microlaryngoscopy under white light and fluorescence illumination (lambda(ex) = 375-440 nm). A quantitative analysis of the fluorescence contrast between neoplastic and surrounding tissue was performed using an optical multichannel analyzer. RESULTS: Carcinoma, carcinoma in situ, and dysplasia showed red fluorescence that could be attributed to the 5-ALA-induced formation of PPIX. The surrounding normal tissue exhibited autofluorescence in the green spectral range, which was greatly reduced within the tumor. The results of macroscopic red fluorescence staining were correlated with the histologic diagnosis. CONCLUSION: According to these preliminary results, the presented method seems to be a promising adjunct diagnostic procedure for the early identification of malignant neoplasms in the larynx. The aim of further investigations is the assessment of sensitivity and specificity and an evaluation of fluorescence-guided laser resections of laryngeal cancer. Lasers Med. Surg. 25:414-420, 1999.

Administration, Topical↗
PubMed1999

[Navigation surgery in diseases of the paranasal sinuses].

BACKGROUND: Since the mid-80s, endonasal sinus surgery has gained significant importance in the treatment of chronic inflammatory sinus disease. Many surgeons have recognized the necessity of developing new methods to increase the safety of this type of surgery. One of the advancements in increasing the safety of endonasal sinus surgery was the development of computer-aided surgical navigation (CAS) systems. METHODS: Since 1996, we have tried several different CAS systems for difficult surgical procedures in sinus and anterior skull base surgery, mainly revision surgery for chronic inflammatory sinusitis and endonasal tumors. During this time, we tried one electromagnetic ("Insta Trak") and two optoelectric systems ("Surgigate" and "Vector Vision"). RESULTS: In our experience, all systems can be used in endonasal sinus surgery; accuracy was satisfactory and varied between 0.1 and 0.5 mm. There were differences with respect to the time of preparation of the system for surgery as well as to the possibility to use different instruments. CONCLUSIONS: Computer-assisted surgical navigation systems today have gained a degree of accuracy which makes them not only suitable but almost necessary, at least for difficult surgical procedures at the anterior skull base, i.e. revision surgery in chronic inflammatory sinus disease. On the long run, these systems will become mandatory for these kinds of procedures. On the other hand, CAS systems cannot substitute thorough anatomical and surgical training.

Computer Systems↗
PubMed1999

[Role of diagnostic imaging in chronic recurrent parotitis in childhood].

BACKGROUND: Chronic recurrent parotitis represents a disease of still uncertain etiology that can be divided into a childhood and an adult form. Sialography is still the imaging procedure of choice. METHOD: We report about a nine-year-old girl who had had six episodes of parotitis in the past two years. MR sialography is presented as an alternative to conventional sialography. MR was performed with a 1.5 T wholebody tomograph using a high resolution 3D-CISS sequence. RESULTS AND CONCLUSION: MR sialography does not require any contrast medium. It primarily images liquid structures, and the flow of saliva can be adequately demonstrated after stimulation with ascorbic acid. These special features of MR sialography allow its use also during acute episodes of sialadenitis, thus providing a significant improvement over conventional sialography. Furthermore, no overlapping occurs as in conventional summation images, due to the multiplanar reconstruction features.

Adult↗
PubMed1999

Ho:YAG laser treatment of hyperplastic inferior nasal turbinates.

OBJECTIVES: Although preliminary studies about the successful use of the Ho:YAG laser in nasal turbinate surgery have been reported, no clinical study has been performed on this procedure. The aim of this prospective clinical study was to assess the long-term effect of Ho:YAG laser in the treatment of hyperplastic inferior nasal turbinates. METHODS: Eighty-five patients with nasal obstruction who did not respond to conservative medical treatment were treated with a pulsed Ho:YAG laser (wavelength of =2080 nm). Fifty-two of these patients were included in this clinical study and were followed for 1 year. RESULTS: Within the first 2 weeks, nasal obstruction was correlated to the extent of nasal crusting. Six months after laser treatment, the mucociliary function test showed no variation compared with the preoperative measurements. One year after laser treatment 77% of the patients demonstrated improved nasal airflow on rhinomanometry and questionnaire. CONCLUSIONS: Ho:YAG-laser treatment of hyperplastic turbinates can be performed as outpatient surgery under local anesthesia and offers controllable ablation of soft tissue in a short operation time with satisfactory results and excellent patient acceptance.

Feasibility Studies↗
PubMed1998

Embryonal rhabdomyosarcoma of the nose in an elderly patient, case report and review of the literature.

Embryonal rhabdomyosarcoma of the head and neck is very rare in adults. We report on an embryonal rhabdomyosarcoma of the nose, occuring in a 74-year-old female patient presenting with nasal congestion as the only clinical symptom. Suspected to be an amelanotic melanoma, further biopsies and histological examinations provided the correct diagnosis. She first underwent a course of chemotherapy which led to a partial shrinkage of the tumor mass which was followed by a complete resection of the residual tumor mass. Biologic behaviour of this tumor must be fully appreciated as treatment is interdisciplinary. Rhabdomyosarcoma should be considered in the differential diagnosis of tumors of the nose and paranasal sinuses not only in children, but also in adults.

Age Distribution↗
PubMed1997

[Fibroblast growth factor (b-FGF) in serum and urine of patients with head-neck malignancies].

BACKGROUND: The angiogenic peptide basic fibroblast growth factor (b-FGF) has been suggested to significantly promote angiogenesis; a central event for the growth and metastasis of solid tumors. Elevated levels of b-FGF in the serum and urine of patients with various types of cancer have been reported. No information exists about b-FGF levels in patients with primary head and neck cancer. The present study was performed to determine serum and urine levels of b-FGF in these patients. METHODS: b-FGF was quantified in the urine of 50 (62.5%) patients with head and neck cancer as well as 30 (37.5%) patients with diseases unrelated to cancer using an immunoassay with a detection limit of 1.0 pg/ml (FGF basic "Quantikine", DFB00. Biermann GmbH, Bad Nauheim, Germany). Urine was collected from patients before breakfast and centrifuged for 10 min at 1000 g. The supernatants were stored at -80 degrees C until the assay was performed. RESULTS: In the serum and urine of all patients, b-FGF was detectable by immunoassay. Cancer patients revealed significant increased serum b-FGF concentrations, in addition, advanced tumor size (T3/4) showed significant increased b-FGF levels in both serum and urine. There seems to be a correlation between serum b-FGF concentrations with degree of histologic differentiation. CONCLUSION: The results of this study demonstrate that b-FGF levels are elevated in serum and urine of patients with primary head and neck cancer. These findings suggest an involvement of b-FGF in the formation of solid tumors. The value of b-FGF as a non-invasive monitoring of treatment response in cancer therapy, the correlation with angiogenesis in histologic sections as well immunohistochemical detection are the aim of further investigations.

Adult↗
PubMed1996

Fluorescence imaging and spectroscopy of 5-aminolevulinic acid induced protoporphyrin IX for the detection of neoplastic lesions in the oral cavity.

BACKGROUND: Semiquantitative fluorescence measurements following topical application of 5-aminolevulinic acid (5-ALA) in 16 patients with neoplastic lesions of the oral cavity were performed. METHODS: Time course and type of porphyrin accumulation were analyzed in neoplastic and surrounding healthy tissue by measuring emission spectra of 5-ALA-induced protoporphyrin IX fluorescence. Fluorescence images in the red and green spectral range from the tumor tissue were recorded with a charge-coupled device camera. RESULTS: Protoporphyrin IX fluorescence was detected in the oral mucosa of all patients after local application of 5-ALA. Protoporphyrin IX in neoplastic tissue accumulated earlier in comparison with the surrounding normal tissue. The maximum fluorescence contrast of 10:1 between tumor and host tissue was generally seen 1-2 hours after application, allowing a demarcation of tumor tissue even with the naked eye. CONCLUSION: Labeling of mucosal lesions of the oral cavity with Protoporphyrin IX fluorescence induced by the local application of 5-ALA seems to be a promising diagnostic procedure for neoplastic lesions that are difficult to visualize under white light examination. It is the aim of further investigations to evaluate the relevance of this new diagnostic procedure as a noninvasive and sensitive method for patients with oral cancer.

Administration, Topical↗