[Teaching otorhinolaryngology in times of COVID-19: to what extent can digital formats replace face-to-face teaching?] / Unterricht in der Hals-Nasen-Ohren-Heilkunde in Zeiten der COVID-19-Pandemie. Wie gut können digitale Formate die Präsenzlehre ersetzen?

OBJECTIVE: Due to the coronavirus disease 19 (COVID-19) pandemic, postgraduate training in otorhinolaryngology in 2020 was transferred completely from face-to-face to digital teaching. This paper assesses whether this change was possible without a reduction in the quality of teaching and learning. METHODS: Results of final written examinations were compared for the years 2016-2020, and the results of the teaching evaluation by the students for 2017-2020. The evaluation by students in 2020 included additional questions related to the switch from face-to-face to digital teaching. Additionally, the lecturers and teachers were asked for their assessments. RESULTS: Results of the final written examination did not show any significant differences between 2016-2019 and 2020. Students were highly satisfied with the digital format, but values did not reach the level of former years with face-to-face-teaching. Especially the interaction with patients and the teaching of manual skills were rated lower in the digital format. Lecturers emphasized the additional workload for preparation of digital teaching. CONCLUSION: The results of written examinations showed no difference between digital and face-to-face teaching. Online communication and interaction were reduced and regarded as cumbersome by students and faculty. Digital solutions providing more interaction and active participation are required. The digital format is more appropriate for teaching basic knowledge than for teaching practical skills.

Photodynamic effects of anthracyclin derivatives on squamous cell carcinoma cell lines of the head and neck.

BACKGROUND AND OBJECTIVE: In the last years, photodynamic therapy, performed with hematoporphyrin derivatives, gained in importance for the treatment of superficially situated malignomas. The use of hematoporphyrin as photosensitizer is limited especially by the low depth of penetration and its side effects. The aim of the present study was to evaluate the effectiveness of photodynamic therapy with anthracyclin derivates in squamous cell carcinoma cell lines. STUDY DESIGN/MATERIALS AND METHODS: The photodynamic effects of the anthracyclin derivates adriamycin and epirubicin as well as the effects of the hematoporphyrin derivatives photofrin-II and photosan-3 were examined and compared in 10 squamous cell carcinoma cell lines derived from head and neck tumors. RESULTS: Beside their cytostatic effect, the applied cytostatics revealed a marked photodynamic effect. A statistically significant difference for photodynamic effects of both cytostatic agents and the hematoporphyrin derivates could not be shown. CONCLUSIONS: These results revealed that the above mentioned cytostatics could be considered as possible alternative photosensitizer for photodynamic therapy.

[Sonographic features of a submandibular epidermoid cyst]. / Sonographische Aspekte einer submandibulär lokalisierten Epidermoidzyste.

We present the case of a 23-year-old man with a few weeks history of a gradually enlarging mass of the right submandibular region. On palpation, the well-defined swelling had an engorged and elastic consistency. Sonography revealed a sharply defined mass with spherical and solid echorich lesions surrounded by areas of liquid. Histological examination of the resected tumour revealed an epidermoid cyst. The wall of the cyst was composed of stratified squamous epithelium with the cystic space containing keratin arranged in layers. Characteristic sonographic findings of epidermoid cysts regularly permit accurate preoperative diagnosis without the need for additional imaging procedures.

Excretion measurement of porphyrins and their precursors after topical administration of 5-aminolaevulinic acid for fluorescence endoscopy in head and neck cancer.

5-Aminolevulinic acid (5-ALA) is a useful agent to enhance the detection of early epithelial lesions in head and neck cancers. It is applied either topically or systemically and converted intracellular into photosensitive protoporphyrin IX (PpIX). By ultraviolet light illumination malignant and fast proliferating lesions are detected by a characteristic red fluorescence and delineated by the bluish fluorescence of healthy tissue. To assess the elimination patterns 5-ALA, porphobilinogen (PBG) and porphyrin were measured 12h and 36h after administration in urine, 12h and 24h after examination in blood and in feces 12h after endoscopy. 5-ALA was applied either by inhalation (250 mg) or mouth rinse (200 mg). After both administration routes, excretion levels in urine returned to background levels within 12 hours after administration and only in feces values are slightly increased for PpIX and total porphyrin. Concentrations in erythrocytes were elevated, but not in plasma. No side effects were observed. According to our results the topical administration of 5-ALA is a useful method with satisfying fluorescence imaging results. Levels of metabolites in urine and plasma return to normal within 12 hours so that skin photosensitization can be neglected.

Number and location of radiolabeled, intraoperatively identified sentinel nodes in 48 head and neck cancer patients with clinically staged N0 and N1 neck.

The value of sentinel node (SN) biopsy for squamous cell carcinoma of the head and neck (HNSCC) has not been determined yet. A critical evaluation of this concept seems to be mandatory with regard to the increasing acceptance of SN biopsy in other tumor entities. Against the background of the results of 48 previously untreated patients, a reproducible technique for SN biopsy in the head and neck level, which has been adjusted to the special topographic conditions of this anatomic region, is presented. Methods included intraoperative SN biopsy, which was performed in 48 previously untreated patients suffering from squamous cell carcinoma (2x lower lip, 8x oral cavity, 20x oropharynx, 15x larynx, 3x hypopharynx). Using ultrasound imaging, 43 patients were staged as N0 necks, and 5 patients were staged as N1 necks. Fine-needle aspiration cytology (FNAC) was performed in cases of doubt. Surgery on the neck was carried out according to the suspected stage of lymphogenic spread once the SN1 as well as one or two further hot nodes (SN2, SN3) had been identified. Numbers and distribution of the intraoperatively excised nodes SN1-3 were documented according to their relation to the tumor location. Post-operatively, the histologic results of the intraoperatively excised nodes SN1-3 were compared to the histologies of the neck dissection specimen. Results showed that in all 48 patients, a SN1 could be identified intraoperatively. In 20 cases an additional SN2 and in 6 cases a SN3 was diagnosed. In carcinomas of the lower lip and oral cavity, the SN1 was found in 4 cases in level I (2x lower lip, 2x floor of the mouth) and in 6 cases in level II (6x lateral tongue). In carcinomas of the oropharynx, the respective nodes were found in 17 of 20 cases in level II (carcinomas of the tonsil) and in 3 cases in level III (carcinomas of the base of the tongue). In supraglottic carcinomas the SN1 was identified in 8 of 10 cases in level II and in 2/5 patients with glottic carcinomas, while in 3/5 glottic carcinomas as well as in all hypopharyngeal carcinomas, the SN1 was found in level III. In relation to the predictiveness of the detected SN, it has to be remarked that in 38 patients a SN1 free of tumor was representative for the regional lymph node status (pN0). An isolated metastasis (pN1) was diagnosed in the SN (9x SN1, 1x SN2) in 10 patients. In conclusion, the results of a SN biopsy modified to a strictly intraoperative method of detection are encouraging. Critical indications showed that a thorough and standardized technical performance of the injection as well as a mandatory, so far unchanged, neck dissection form the basis for the development of a SN concept for SCCs of the upper aerodigestive tract. The value of the SN concept, however, currently remains unclear for patients suffering from HNSCC.

[The sentinel node concept in head and neck squamous cell carcinoma--a critical analysis in 100 patients]. / Das Sentinel Node Konzept bei Plattenepithelkarzinomen der oberen Luft- und Speisewege - eine kritische Analyse an 100 Patienten.

BACKGROUND: The value of Sentinel Node (SN) concept is a current issue in clinical oncology. Few investigations deal with SN biopsy in head and neck squamous cell carcinomas (HNSCC). For this reason the SN concept was investigated based on the results of the so far largest group of 100 patients. METHOD: Three groups of patients were investigated. Group 1: In 30 patients (6 x oral cavity, 24 x oropharynx) a dynamic lymphoscintigraphy was performed. Group 2: 60 previously untreated patients (12 x oral cavity, 23 x oropharynx, 16 x larynx, 9 x hypopharynx); neck lymph node status on ultrasound imaging: 39 x N0, 5 x N1, 16 x N2, intraoperative identification of the SN during neck dissection (ND) accomplished according to the extent of assumed lymphogenic metastatic spread; postoperative comparison of the histological result of the SN with the neck dissection specimen. Group 3: 10 previously treated patients (1 x oral cavity, 5 x oropharynx, 1 x larynx, 3 x hypopharynx) in whom an intraoperative SN biopsy was performed. RESULTS: Group 1: In 20/30 patients a cervical lymph drainage could be visualized on dynamic lymphscintigraphy and an activity enrichment above the mean metastatic region could be identified transcutaneously. Group 2: In 34 patients the tumorfree SN1 reflected the regional lymph node status. In 9 patients an isolated tumor metastasis (pN1) was found in the intraoperatively identified SN1 and in a further patient in the SN2 (pN1). CONCLUSION: The results of SN biopsy are encouraging in cases of clinical N0-necks. Nevertheless the data demonstrates that extensive investigations followed by a critical analysis of the results are required. The presented results suggest that the value of the SN concept seems to be of minor importance in cases of advanced lymphogenic metastatic spread.

Value of sentinel lymphonodectomy in head and neck cancer patients without evidence of lymphogenic metastatic disease.

OBJECTIVE: Only few communications deal with the value of sentinel node (SN) biopsy for head and neck squamous cell carcinoma (HNSCC). Based on the results of 38 investigated patients with clinically N0-neck the feasibility of SN biopsy in HNSCC is critically discussed. PATIENTS AND METHODS: Thirty-eight previously untreated patients with clinically N0-neck were staged by intraoperative SN biopsy. After intraoperative identification of the hottest node (SN(1)) and further less tracer accumulating lymph nodes (SN(2), SN(3)), patients were treated by different types of neck dissection (ND), adjusted to the location and extent of the primary tumour. Postoperatively the histologic results of the SN(1-3) and the entire ND specimen were compared. RESULTS: The stage of cervical metastatic disease was demonstrated by a disease-free SN(1) in 32 patients. In five patients an isolated metastasis could be proven in the intraoperatively identified SN(1), while in the remaining patient an isolated metastasis was found in the SN(2). CONCLUSION: Intraoperative SN biopsy seems to be valuable for the detection of occult lymph node metastases in HNSCC. This method might help to limit the extent of ipsilateral ND, if used as an intraoperative staging procedure to investigate the first draining tracer accumulating lymph nodes (SN(1-3)).

Ultrasound-guided piezoelectric extracorporeal shock wave lithotripsy of parotid gland calculi.

PURPOSE: The introduction of piezoelectric extracorporeal shock wave lithotripsy (ESWL) has changed therapy for salivary calculi. This method seems especially suitable for treating calculi in the parotid gland. The purpose of this study was to evaluate ESWL in patients with such calculi. METHODS: From November 1990 to November 1999, all patients with sialolithiasis of the parotid gland were treated with piezoelectric ESWL. Three different lithotriptors were used over the 9-year study period. Results were analyzed according to both the patients' clinical status and follow-up sonograms. RESULTS: In total, 42 patients (21 women, 21 men; mean age, 59 years) were treated with ESWL. The mean follow-up period for all patients was 63 months (range, 7-96 months). After ESWL had been performed, 71% of the patients were completely free of symptoms, and 21% had marked improvement of their symptoms. Sixty-seven percent were completely free of calculi, and 27% had a marked reduction in the size of their calculi. Adverse effects of ESWL included temporary glandular swelling (4 patients), blood-tinged salivary secretions (9 patients), petechiae on the skin surface (3 patients), and parotid abscess (1 patient). CONCLUSIONS: ESWL is an outpatient procedure that can be performed without anesthesia and with scarcely any discomfort for patients. Conventional surgical procedures such as subtotal parotidectomy may be almost entirely replaced by ESWL because of the excellent treatment results and a very low rate of complications associated with ESWL. ESWL should be considered the treatment of choice for parotid calculi.

Experimental and clinical results of Er:YAG laser stapedotomy.

BACKGROUND AND OBJECTIVE: At the beginning of the 1980s, different laser types were used for stapes surgery to reduce potential harm to inner ear structures through manipulation with conventional instruments during stapedotomy. Most clinical studies were carried out with the CO2 or the argon laser. The Er:YAG laser has been used rarely in patients with otosclerosis. STUDY DESIGN/MATERIALS AND METHODS: In an experimental study on 54 human petrous bones, the optimal laser energy parameter for dissection of the posterior stapes crus and the footplate perforation were determined. With these parameters, stapedotomy was carried out with the Er:YAG laser in 29 patients with otosclerosis with a conventional dissection of the incudostapedial joint and the stapedius muscle tendon. The Er:YAG laser was used (60 or 100 mJ, 3-6 pulses) for dissection of the posterior stapes crus and footplate perforation. RESULTS: No intra- or postoperative complications were observed in all 29 patients. Vertigo and hearing loss were not observed intra- or postoperatively. The postoperative hearing results (improvement of the air-bone gap) was in all cases satisfactory (median remaining air bone gap, 8.1 dB). The median operation time was 29 minutes (15-42 minutes) and did not show a significant prolongation in comparison to the conventional technique. In 1 of the 29 patients, the footplate perforation needed to be carried out conventionally. CONCLUSION: For the first time, Er:YAG laser parameters have been optimized and refined in a human petrous bone model and were then used in a clinical setting. According to the presented results, the Er:YAG laser seemed to be a very suitable instrument for stapedotomy.

[Studies on significance of sentinel lymphadenectomy in pharyngeal and laryngeal carcinoma]. / Untersuchungen zum Stellenwert der Sentinel Lymphonodektomie bei Karzinomen des Pharynx und Larynx.

BACKGROUND: Management of the suspected N0-neck (sonography and CT) in squamous cell carcinoma (SCC) of the head and neck is discussed controversially. The question arises whether the sentinel node (SN) concept as it is performed in different areas of clinical oncology is applicable to ear, nose, and throat medicine. METHODS: Nine male patients with SCC were studied (4 oropharynx, 2 hypopharynx, and 3 larynx) in whom different lymph node status was diagnosed clinically (5 x N0, 2 x N1, 2 x N2c). After intraoperative scintillation probe detection, the histological examination of the SN with neck dissection (ND) specimen followed. RESULTS: In 7 of 9 cases SN detection was successful. In 4 of 5 cases of clinical N0 status, SN, and ND specimens were free of tumor histologically, while in one patient radiolabel-identified SN showed tumor cells in histological examination. In 2 patients with clinical N1 neck, SN, and ND were histologically tumor-free in one patient and contained one single tumor metastasis located in the SN in the other patient. In 2 patients with clinically and histologically proven N2c neck, lymph nodes located in regions II and III showed metastasis including capsular rupture. In both cases no lymph node radioactivity was detectable during the operation. CONCLUSIONS: The results suggest that sentinel lymphonodectomy may be suited for ear, nose, and throat medicine. Before it is applied to clinical practice, further problems must be resolved. These include the short distance between the primary injection side and lymph nodes and the influence of intranodal tumor metastasis on the uptake of the radiolabeled tracer.

Morphological correlates of urinary enzyme loss after extracorporeal lithotripsy.

Urinary loss of the tubular marker enzyme N-acetyl-beta-D-glucosaminidase (NAG) immediately following extracorporeal lithotripsy suggests corresponding morphological changes in the kidney. To date, the morphological correlate of the enzymuria remains unclear. In this animal study with Wistar rats acute morphological changes in the tubulus cells beneath isolated tubulus necrosis were demonstrated. The mechanically induced lesions of the cell organelles included fragmentation of the lysosomes and severe alterations of the cell membrane. The tubulus damage was quantified. With the help of histochemical NAG staining and electron microscopic observations, a significant correlation between number and intensity of shock waves and tubular damage was found. The intracellular lesions described here are at least part of the morphological basis of shock-wave-induced enzymuria. The results show that enzymatic changes in urine reflect visible renal damage.