Biomedical subjects
Publications and source records attributed to W Lehmann.
Sialolithiasis is a relatively frequent occurrence; however, cases of sialolithiasis originating around a "foreign body" nidus are rare. We describe a patient with submandibular sialolithiasis organized around a vegetal nidus and discuss the etiology of the case.
We report on the development and characterization of a new composite material consisting of amorphous carbonated apatite, Ca(5)(PO(4), CO(3))(3)(OH), and microstructured poly(hydroxyacetic acid), polyglycolide (PGA). This material is able to keep the pH of a surrounding solution within the physiological range (7.2-7.6). This was achieved by chemical fine-tuning of the counterplay between the acidic degradation of the polyester and the basic dissolution of calcium phosphate. Microporous samples with pore sizes of <1 microm and compact samples were prepared. The biological behavior was assayed in vitro by long-term osteoblast culture. Morphological and biochemical analyses of cell differentiation revealed excellent biocompatibility, leading to cell attachment, collagen and osteocalcin expression, and mineral deposition. This material could be of use as a biodegradable bone substitution material and as a scaffold for tissue engineering.
OBJECTIVE: To present our initial experience with sialendoscopy of the parotid duct. STUDY DESIGN METHODS: Diagnostic and interventional sialendoscopy procedures were performed in 79 and 55 cases, respectively. Diagnostic sialendoscopy was used to classify ductal lesions into sialolithiasis, stenosis, sialodochitis, and polyps. Interventional sialendoscopy was used to treat these disorders. The type of endoscope used, the type of sialolithiasis fragmentation and/or extraction device used, the total number of procedures, the type of anesthesia, and the number and size of the sialoliths removed were the dependent variables. The outcome variable was the endoscopic clearing of the ductal tree and resolution of symptoms. RESULTS: Diagnostic sialendoscopy was possible in all cases, with an average duration of 26+/-14 minutes and no complications. Interventional sialendoscopy was successful in 85% of cases, with an average duration of 73+/-43 minutes (+/- standard deviation). Multiple procedures were performed in 45% of cases, general anesthesia was used in 24%, and parotidectomy in 2%. Multiple sialoliths were found in 58% of ducts and associated with more procedures under general anesthesia and longer operations. The average size of sialoliths was 3.2+/-1.3 mm; larger stones were associated with more procedures under general anesthesia, longer and multiple procedures, use of fragmentation, and sialendoscopy failures. Sialolithiasis fragmentation was required in 10% of cases, with a success rate of 70%. Semirigid sialendoscopes performed better than flexible ones. Complications were mostly minor but were encountered in 12% of cases. CONCLUSIONS: Diagnostic sialendoscopy is a new technique for evaluating salivary duct disease, a technique which is associated with low morbidity. Interventional sialendoscopy allows the extraction of sialoliths in most patients, preventing open gland excision.
OBJECTIVE: To evaluate the possibility, complications, and efficacy of endoscopic neck dissection (END) in a porcine model. DESIGN: Experimental self-controlled study. SUBJECTS: Minipigs. INTERVENTION: Endoscopic neck dissection was performed using general anesthesia with techniques adapted from laparoscopic surgery. The tissue specimens removed were divided according to porcine equivalents of human neck groups. After the completion of END, open-neck dissection was performed using standard surgical techniques, and the remaining tissue within each neck group was retrieved. A pathologist evaluated each specimen without knowing its exact origin in terms of neck group or side and the type of surgical technique used. For each specimen, the number of retrieved lymph nodes and their anatomical integrity were analyzed. RESULTS: Ten neck dissections were performed in 8 minipigs without any major complications. The number of retrieved lymph nodes by END was 18.4 +/- 7.4 (mean +/- SD). Completed open-neck dissection retrieved an additional 3.3 +/- 1.8 lymph nodes. The efficacy rate of END was 88% +/- 10% (+/ -SD). The majority of retrieved lymph nodes were intact, with less than 5% of nodes exhibiting crushing artifacts. CONCLUSIONS: Endoscopic neck dissection in a porcine model seems to be free of major complications and able to retrieve the majority of neck lymph nodes. A larger number of animals and their survival need to be studied before human studies can begin.
BACKGROUND: This study was conducted to evaluate quality of life (QOL) and functional outcome in patients with carcinomas of the larynx and hypopharynx treated with accelerated radiotherapy (RT). METHODS: Between January 1991 and September 1996, 21 patients treated with accelerated concomitant boost RT schedule (69.9 Gy in 5. 5 weeks) for laryngeal (n = 10) or hypopharyngeal (n = 11) carcinomas and who remained free of disease at 1-year minimum follow-up were evaluated. The functional outcome was assessed by the subjective Performance Status Scale for Head and Neck cancer (PSSHN) and general QOL by the European Organization for Research and Treatment of Cancer Core QOL questionnaire (EORTC QLQ-C30). The median length of follow-up was 37 months (range, 13 to 75). RESULTS: The PSSHN scores were 89, 84, and 86, respectively, for eating in public, understandability of speech and normalcy of diet (100 = normal function). Significantly lower scores for understandability of speech were observed in patients with advanced and laryngeal carcinomas. Normalcy of diet was affected negatively by the severity of xerostomia. All mean functional scale scores of the EORTC QLQ-C30 module were 20% to 25% below the higher score. Most of these scale scores were significantly affected by the severity of xerostomia. CONCLUSIONS: Patients treated with concomitant boost RT for laryngeal and hypopharyngeal carcinomas appear to have similar QOL and functional outcome to those reported for patients treated with conventional or hyperfractionated RT. As expected, many QOL scales were affected by the severity of xero- stomia.
The goal of this work is to present our results of the intradermic infiltration with botulinum toxin in patients with Frey syndrome. Sixteen hemifaces in 15 patients were studied. Gustatory stimulation was evoked by sucking on a slice of lemon while measurements were done on both hemifaces, with the normal side being used as a control. Skin temperature and color (erythema) were measured with a digital surface thermometer and a skin chromameter, respectively. Sweat quantity and surface were measured by using the previously described blotting paper and iodine-sublimated paper histogram methods, respectively. Testing was repeated 2 weeks after skin infiltration with botulinum toxin (dilution of 50 U/mL). The interinjection distances were 1 cm, and 0.1 mL (5 U) was infiltrated at each injection site. Frey syndrome complaints disappeared in all patients. Small residual amounts of sweat were measurable. The difference in sweat quantity before and after botulinum toxin infiltration was significant in every patient (P < 0.001). Skin temperature and color measurement gave inconclusive results. In conclusion, Frey syndrome treatment with botulinum toxin is an efficient and well-tolerated technique. Further work should address the optimal injection parameters.
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PURPOSE: To evaluate the accuracy of magnetic resonance (MR) sialography in detecting salivary glandular calculi and ductal stenoses. MATERIALS AND METHODS: In a prospective study, 64 salivary glands in 61 consecutive patients with acute or recurrent parotid or submandibular glandular swelling were examined by using three-dimensional (3D) extended-phase conjugate-symmetry rapid spin-echo (EXPRESS) MR imaging. Transverse and sagittal-oblique source images and maximum intensity projection images were obtained. All MR images were analyzed independently by two radiologists, without knowledge of the final diagnosis. The reference standard was conventional sialography, ultrasonography (US), and sialendoscopy with or without surgery in 31 glands and was conventional sialography and US in 33 glands. RESULTS: Final diagnoses included sialolithiasis (n = 23), sialolithiasis and stenosis (n = 9), stenosis without lithiasis (n = 11), early Sjögren syndrome without ductal stenosis (n = 2), ductal displacement (n = 3), and normal salivary glands (n = 16). The sensitivity, specificity, and positive and negative predictive values of MR sialography to detect calculi were 91%, 94%-97%, 93%-97%, and 91%, respectively. False-negative readings occurred due to calculi with a diameter of 2-3 mm in nondilated salivary ducts. Ductal stenosis was assessed, with a sensitivity of 100%, specificity of 93%-98%, positive predictive value of 87%-95%, and negative predictive value of 100%. Interobserver agreement was very good (kappa = 0.85-0.97). CONCLUSION: MR sialography with 3D EXPRESS imaging enables reliable prediction of salivary gland calculi and stenoses.
OBJECTIVE: To evaluate and compare the performances of FDG-PET imaging, MRI and clinical examination in the detection of residual tumour 3 months after treatment of patients with head and neck squamous cell carcinoma. PATIENTS: A consecutive sample of 50 patients with squamous cell carcinoma of the oral cavity, oropharynx, hypopharynx or larynx, or a cervical lymph node metastasis from an unknown primary site excluding T1 lip and T1 vocal cord tumours. METHODS: Treatment outcome was assessed after 3 months by clinical examination, MRI, and FDG-PET scan. Sensitivity, specificity and accuracy were calculated relative to proven biopsy of residual tumour or a clinical follow-up of 4 months. RESULTS: Residual cancer was confirmed in 8 patients (16%), while the clinical follow-up was unsuspicious in the remaining 42 patients. PET-FDG had a sensitivity of 100% as compared to MRI (88%) and clinical examination (63%). Specificity was higher for clinical examination (90%), intermediate for MRI (83%) and lowest for PET-FDG (74%). CONCLUSIONS: This study finds very high sensitivity for PET-FDG in the detection of residual tumour. However, its lower specificity, lack of anatomical resolution, and high cost, require further studies to determine its role in routine screening.
INTRODUCTION: Objective evaluation methods for facial nerve function are yet to be standardised. Unresolved issues include what should be measured for different facial movements and how these measurements should be performed. METHODS: 5 facial mimics were analysed in normal subjects and in patients with facial paralysis. For each mimic the best measurement was determined and two global indexes derived. RESULTS: The best measurements were of surfaces close to the moving facial zone. These measurements and the global indexes correlated well with gradings by the House-Brackmann scale.
AIM: The objective of this study was to compare screening ultrasound (US) obtained in patients with squamous cell carcinoma of the head and neck with F-18-FDG PET and to evaluate if US obtained before F-18-FDG PET has the potential to enhance patient management by the detection of additional lesions. METHOD: 28 patients were prospectively included in the study (7 females and 21 males; range: 28-82 years). All had one follow-up examination after surgical treatment and/or radiotherapy using a combination of US and F-18-FDG PET on the same day (6-35 months after the end of treatment). Outcome was determined by either biopsyproven cancer recurrence or negative clinical follow-up for additional 6 months after this examination. RESULTS: Regarding only the regions of the neck evaluated with both methods, US detected 25 suspect lesions vs. 9 lesions detected by F-18-FDG PET. Descriptive statistical analysis showed better sensitivity, specificity and accuracy of F-18-FDG PET. Only in 3 patients a lesion was detected in the same anatomical region using both methods. One patient was false positive with both methods. In another patient US detected a calcified right carotid artery plaque that lead to surgical therapy. CONCLUSION: F-18-FDG PET is better for the detection of clinically relevant lesions in the follow-up of patients with squamous cell carcinoma of the head and neck. In this study, the additional value of morphological information obtained by screening US performed before the PET scan is limited. US may not be a suitable test to improve interpretation of PET examinations.
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OBJECTIVE: To evaluate the incidence of Frey syndrome (auriculotemporal nerve syndrome) after parotidectomy with and without placement of a subcutaneous implant and to examine the relationship between different implants and postoperative wound complications (hematoma, seroma, salivary fistula). DESIGN: A prospective nonrandomized controlled trial. SETTING: A primary care and referral university hospital center. PATIENTS: All patients scheduled for parotidectomy from April 1994 through August 1998 were eligible. Seventy patients were enrolled (2 refused). All 70 patients were evaluated for wound complications. Sixty patients with a follow-up of more than 1 year were evaluated for Frey syndrome. INTERVENTION: The choice of implant was left to the individual surgeon: 24 patients had no implant; 7, lyophilized dura implant; 7, polyglactin 910-polydioxanone (Ethisorb) implant; and 32, expanded polytetrafluoroethylene (e-PTFE) implant. OUTCOME MEASURES: The incidence of Frey syndrome was evaluated (1) subjectively by history (clinical Frey syndrome) and (2) objectively by using 2 newly developed tests. Both hemifaces were tested, with the normal side being used as a control. RESULTS: Clinical Frey syndrome was present in 12 patients: 11 without implants (11/24 [53%]) and 1 with an implant (1/46 [2%]) (P<.001). Objective tests were positive in 24 patients: 16 (76%) of 21 without implants and 8 (20%) of 39 with implants (P<.001). In the implanted patients, the objective tests were positive in 71% (5/7) of those with lyophilized dura, 14% (1/7) of those with Ethisorb, and 8% (2/29) of those with e-PTFE implants (P<.001). Wound complications included hematoma in 5 patients (7%), seroma in 4 patients (6%), and salivary fistula in 15 (21%). Salivary fistula occurred more frequently with Ethisorb (57%) and e-PTFE (25%) implants (P = .04). CONCLUSIONS: In patients without an implant, the incidence of Frey syndrome is 50% for subjective and 80% for objective evaluation. In patients with an implant, these incidences are 3% and 10%, respectively. Some implants are associated with a higher incidence of salivary fistula.
BACKGROUND: Surgical management of advanced neck disease remains controversial when a conservative approach based on radiotherapy is retained for primary tumors. The objective of this study was to evaluate retrospectively treatment results in pharyngeal cancers presenting with N2-N3 neck disease, using neck dissection followed by radical locoregional radiotherapy (RT) and to compare these results with those obtained in patients treated by radical RT alone. METHODS: From August 1991 to November 1996, 41 patients with carcinomas of the oro- or hypopharynx were staged as T1-T3 N2-N3 M0 (American Joint Committee on Cancer [AJCC] stage IV). Twenty-four patients were treated with neck dissection followed by RT (group 1) and 17 patients with radical RT (group 2) using a progressively accelerated concomitant boost schedule. Chemotherapy was delivered to 6 patients in group 1 and 8 in group 2 partially concomitantly with RT. RESULTS: Three-year actuarial locoregional control was 73% and 55% for groups 1 and 2, respectively (p = .52). The corresponding 3-year actuarial overall survival rates were 37% and 50% (p = .42). Severe postoperative complications were observed after neck dissection in four patients (16%). Acute toxicity during RT was similar in the two groups. Late toxicities were also similar, except for two patients in group 1 who developed severe laryngeal edema. CONCLUSIONS: Neck dissection followed by radical RT to the primary tumor and neck represents a valid treatment option in this subset of patients, allowing good control of advanced neck disease, while at the same time conserving pharyngolaryngeal function. However, for patients who are at high risk of severe postoperative complications, radical RT can be considered a worthy alternative, particularly for oropharyngeal carcinomas.
Two newly developed tests for gustatory sweating, providing both quantitative and topographic information, are presented. In both tests a paper stencil shaped to fit the complex anatomy of the parotid region is used. The blotting paper technique uses the difference in weight before and after gustatory stimulation to measure the amount of sweating. The iodine-sublimated paper histogram (ISPH) uses iodine sublimated office paper that changes colour when wet. The paper stencil is than digitized and a histogram algorithm applied to measure the area of sweating. A calibration of these tests with known and appropriate quantities of saline is presented.
OBJECTIVE: Analyze the incidence and factors responsible for postparotidectomy facial nerve paralysis when the surgery is performed with the routine use of facial nerve monitoring. STUDY DESIGN: A prospective, nonrandomized study. METHODS: Seventy consecutive patients underwent parotidectomy with intraoperative facial nerve monitoring. Two devices were used: a custom mechanical transducer and a commercial electromyograph-based apparatus. All patients were analyzed, including those with cancer and those with deliberate or accidental sectioning of facial nerve branches. The outcome variables were the motor facial nerve function according to the House-Brackmann grading scale (HB) at 1 week (temporary paralysis) and 6 to 12 months (definitive paralysis). Facial nerve grading was performed blindly from reviewing videotapes. RESULTS: The overall incidence of facial paralysis (HB>1) was 27% for temporary and 4% for permanent deficits. Most of the deficits were partial, most often concerning the marginal mandibular branch. Temporary deficits with HB scores of greater than 2 were only present in patients with parotid cancer or infection. Permanent deficits were present in three patients, including one patient with facial nerve sacrifice. Factors significantly associated with an increased incidence of temporary facial paralysis include the extent of parotidectomy, the intraoperative sectioning of facial nerve branches, the histopathology and the size of the lesion, and the duration of the operation. CONCLUSIONS: Despite a stringent accounting of postoperative facial nerve deficits, these data compare favorably to the literature with or without the use of monitoring. An overall incidence of 27% for temporary facial paralysis and 4% for permanent facial paralysis was found. Although the lack of a control group precludes definitive conclusions on the role of electromyograph-based facial nerve monitoring in routine parotidectomy, the authors found its use very helpful.
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OBJECTIVE: To report on three cases of severe facial skin burns resulting from intraoperative facial nerve monitoring in patients undergoing parotidectomies. STUDY DESIGN: This study is a retrospective case review. SETTING: A tertiary referral center. PATIENTS: This study includes three patients who underwent parotidectomies with concurrent facial nerve monitoring. RESULTS: Facial skin burns were proven to result from a technical defect of the intraoperative facial nerve monitoring device. Burns were sustained at electrode insertion sites and their extent was related to the duration of monitoring. The most probable explanation of these burns is electrolysis. CONCLUSIONS: Successful retracing of technical defaults with biomedical engineers at the device manufacturer have led to the upgrade of the facial nerve monitor apparatus. The benefits of facial nerve monitoring largely outweigh the fortuitous occurrence of skin burns reported in this study. Therefore, this complication should not represent a drawback to the use of facial nerve monitoring.