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One of the major sources of uncertainty in predictions of wind farm noise (WFN) reflect parametric and model structure uncertainty. The model structure uncertainty is a systematic uncertainty, which relates to uncertainty about the appropriate mathematical structure of the models. Here we quantified the model structure uncertainty in predicting WFN arising from multi-input models, including nine ground impedance and four wind speed profile models. We used a numerical ray tracing sound propagation model for predicting the noise level at different receivers. We found that variations between different ground impedance models and wind speed profile models were significant sources of uncertainty, and that these sources contributed to predicted noise level differences in excess of 10 dBA at distances greater than 3.5 km. We also found that differences between atmospheric vertical wind speed profile models were the main source of uncertainty in predicting WFN at long-range distances. When predicting WFN, it is important to acknowledge variability associated with different models as this contributes to the uncertainty of the predicted values.

This paper presents results from a one-year study of indoor annoyance and self-reported sleep times for two participants located near different wind farms. Continuous measurements of outdoor and indoor noise and meteorological conditions were taken at each location for the duration of the study. In at least 50% of the annoyance recordings, participants described noise as “swish” or “swoosh.” Furthermore, the majority of the annoyance recordings occurred at nighttime and in the early morning. The third quartile of A-weighted indoor sound pressure level [SPL(A)], between 27 and 31 dBA, was associated with an 88% increased probability of annoyance compared to the lowest reference quartile, which was between 12 and 22 dBA [odds ratio and 95% confidence intervals, 7.72 (2.61,22.8), p < 0.001]. The outdoor SPL(A) was also predictive of annoyance but only between 40 and 45 dBA. The outdoor prevalence of amplitude modulation (AM), defined as the percentage of time that AM was detectable by an algorithm for each annoyance period, was also associated with annoyance. Self-reported sleep efficiency (time spent asleep relative to time in bed available for sleep) was significantly associated with nighttime annoyance (β = −0.66, p = 0.02) but only explained a small fraction of the variance (R2 = 5%).

The presence of amplitude modulation (AM) in wind farm noise has been shown to result in increased annoyance. Therefore, it is important to determine how often this characteristic is present at residential locations near a wind farm. This study investigates the prevalence and characteristics of wind farm AM at 9 different residences located near a South Australian wind farm that has been the subject of complaints from local residents. It is shown that an audible indoor low-frequency tone was amplitude modulated at the blade-pass frequency for 20% of the time up to a distance of 2.4 km. The audible AM occurred for a similar percentage of time between wind farm percentage power capacities of 40 and 85%, indicating that it is important that AM analysis is not restricted to high power output conditions only. Although the number of AM events is shown to reduce with distance, audible indoor AM still occurred for 16% of the time at a distance of 3.5 km. At distances of 7.6 and 8.8 km, audible AM was only detected on one occasion. At night-time, audible AM occurred indoors at residences located as far as 3.5 km from the wind farm for up to 22% of the time.

Amplitude modulation (AM) is a characteristic feature of wind farm noise and has the potential to contribute to annoyance and sleep disturbance. Detection, quantification and characterisation of AM is relevant for regulatory bodies that seek to reduce adverse impacts of wind farm noise and for researchers and wind farm developers that aim to understand and account for this phenomenon. We here present an approach to detect and characterise AM in a comprehensive and long-term wind farm noise data set using human scoring. We established benchmark AM characteristics, which are important for validation and calibration of results obtained using automated methods. We further proposed an advanced AM detection method, which has a predictive power close to the practical limit set by human scoring. Human-based approaches should be considered as benchmark methods for characterising and detecting unique noise features.

Insomnia and obstructive sleep apnea (OSA) commonly co-occur. Approximately 30-50% of patients with OSA report clinically significant insomnia symptoms, and 30-40% of patients with chronic insomnia fulfil diagnostic criteria for OSA. Compared to either insomnia or OSA alone, co-morbid insomnia and sleep apnea (COMISA) is associated with greater morbidity for patients, complex diagnostic decisions for clinicians, and reduced response to otherwise effective treatment approaches. Potential bi-directional causal relationships between the mechanisms and manifestations of insomnia and OSA could play an integral role in the development and management of COMISA. A greater understanding of these relationships is required to guide personalized diagnostic and treatment approaches for COMISA. This review summarizes the available evidence of bi-directional relationships between COMISA, including epidemiological research, case studies, single-arm treatment studies, randomized controlled treatment trials, and objective sleep study data. This evidence is integrated into a conceptual model of COMISA to help refine the understanding of potential bi-directional causal relationships between the two disorders. This theoretical framework is essential to help guide future research, improve diagnostic tools, determine novel therapeutic targets, and guide tailored sequenced and multi-faceted treatment approaches for this common, complex, and debilitating condition.

The large-scale expansion of wind farms has prompted community debate regarding adverse impacts of wind farm noise (WFN). One of the most annoying and potentially sleep disturbing components of WFN is amplitude modulation (AM). Here we quantified and characterised AM over one year using acoustical and meteorological data measured at three locations near three wind farms. We found that the diurnal variation of outdoor AM prevalence was substantial, whereby the nighttime prevalence was approximately 2 to 5 times higher than the daytime prevalence. On average, indoor AM occurred during the nighttime from 1.1 to 1.7 times less often than outdoor AM, but the indoor AM depth was higher than that measured outdoors. We observed an association between AM prevalence and sunset and sunrise. AM occurred more often during downwind and crosswind conditions. These findings provide important insights into long term WFN characteristics that will help to inform future WFN assessment guidelines.

Amorphous molybdenum sulfide is an attractive electrode material for Li/Mg batteries and an efficient Pt-free catalyst for the hydrogen evolution reaction in water. By using the electrochemical quartz crystal microbalance (EQCM) analysis, new insights were gained into the electrochemical polymerization of the [Mo

Objectives We assessed the severity of dysphagia before and after oral cavity cancer surgery.

The effectiveness of the cough reflex in patients who aspirated following radiation for head and neck cancer was evaluated in 89 patients (49 chemoradiation, 33 postoperative radiation, and 7 radiation alone). All patients had modified barium swallow because of dysphagia. The cough reflex was graded as present and effective, ineffective, intermittently effective, or absent. All patients were cancer-free at the time of the swallowing study. The cough reflex was present and effective in 46 patients (52%), ineffective in 17 patients (19%), and absent in 26 patients (29%) on initial investigation. Among the 43 patients who had ineffective or absent cough reflex, their treatment was chemoradiation (26), postoperative radiation (13), and radiation alone (4). In 30 patients who had sequential modified barium swallow, the cough reflex was constantly effective, ineffective, or intermittently effective in 12 (40%), 13 (43%), and 5 (17%) patients, respectively. The cough reflex was frequently ineffective or absent in patients who aspirated following radiation for head and neck cancer. Cough may also be intermittently ineffective to protect the airways following radiation.

Purpose The aim of this study was to assess the survival, pattern of failure, morbidity, and prognostic factors of concurrent chemoradiation for locally advanced oropharyngeal cancer. Materials and methods A retrospective survey of patients who underwent chemotherapy and radiation for locally advanced oropharyngeal carcinoma at the Veteran Affairs North Texas Health Care System, Dallas, Tex. Results Between December 1999 and September 2004, 48 patients with locally advanced oropharyngeal cancer underwent concurrent chemotherapy and radiation. At a median follow-up of 23 months, the 3- and 5-year survival for the whole group were, respectively, 52% and 41%. Seventeen patients (35%) developed recurrences. There were 12 (25%) locoregional failures (6 local failures alone and 6 local and regional failures). Distant metastases developed in 8 patients (5 alone, 3 associated with locoregional failures). Four patients (8%) developed second primaries. No difference was observed in survival between base of tongue and tonsillar carcinoma (P = .32). The 5-year survival for T1-T2 and T3-T4 tumors was, respectively, 84% and 27% (P = .01). No patient with T1-T2 tumors developed distant metastases (P = .04). Forty-five patients (94%) developed toxicity grade 3 to 4 (40 mucositis and 26 hematological). The median weight loss was 18 lb (range, 0–47 lb). Eight patients (16%) developed aspiration pneumonia during and after treatment. Five patients (10%) died of aspiration (2 during and 3 post treatment). Four patients (8%) developed esophageal strictures requiring repeated dilatations post treatment. Two patients had radionecrosis (1 soft tissue and 1 bone) requiring hyperbaric oxygen. Eighteen patients (37%) had prolonged tube feedings (>3 months) after treatments because of severe dysphagia or aspiration. Conclusion Concurrent chemoradiation provided good locoregional control for locally advanced oropharyngeal carcinoma. Patients with small tumors (T1-T2) had excellent survival. The poor prognosis associated with large tumors may be due to the risk of developing distant metastases. Acute and late toxicities remained significant. Aspiration pneumonia and severe dysphagia were the most prevalent complications of the combined modality approach.

Background: To evaluate the impact of chemoradiation and postoperative radiation on patients’ quality of life (QOL) in a single institution. Methods: A retrospective analysis of 101 patients who had treatment for locally advanced head and neck cancer in a single institution. Forty-seven patients had chemotherapy and radiation, 54 patients underwent postoperative radiation. QOL was assessed with the University of Washington (UW), and the Hospital Anxiety (HA) and Depression (HD) questionnaires. All patients were free of disease at the survey time. Results: Mean and median UW scores were not different between the 2 groups: chemoradiation (65/67), postoperative radiation (62/63). Mean and median HA scores were 7.6/7 (chemoradiation), and 8.3/8 (postoperative radiation). Mean and median HD scores were 6.7/7 (chemoradiation), and 7.1/7 (postoperative radiation). Forty-four patients developed complications, with mean/median UW, HA, and HD scores of 55/55, 9.9/8, and 8.9/9, respectively. These scores were significantly different compared to the 57 patients without complications: 70/70 (p = 0.0001), 6.5/6 (p = 0.001), and 8.9/9 (p = 0.0001). Conclusion: There was no significant difference in QOL between chemoradiation and postoperative radiation in this retrospective study with a relatively short follow-up in the chemoradiation group. In addition, there were more patients with resectable disease in the postoperative group which may explain the lack of difference in QOL between the two groups. Patients who developed complications following treatment experienced lower QOL, more anxiety and depression. Our study raised the need to conduct a prospective randomized study to assess the real impact of chemoradiation and postoperative radiation on patients’ QOL.

Background and purpose We would like to assess the prevalence of aspiration before and following chemoradiation for head and neck cancer. Patients and methods We reviewed retrospectively the Modified Barium Swallow (MBS) in 63 patients who underwent concurrent chemotherapy and radiation for head and neck cancer. MBS was performed prior to treatment to determine the need for immediate gastrostomy tube placement. MBS was repeated following treatment to assess the safety of oral feeding prior to removal of tube feeding. All patients were cancer free at the time of the swallowing study. No patient had surgery. Dysphagia severity was graded on a scale of 1–7. Tube feedings were continued if patients were diagnosed to have severe aspiration (grade 6–7) or continued weight loss. Patients with abnormal swallow (grade 3–7) received swallowing therapy following MBS. Results Before treatment, there were 18 grade 1, 18 grade 2, 9 grade 3, 8 grade 4, 3 grade 5, 3 grade 6, and 4 grade 7. Following chemoradiation, at a median follow-up of 2 months (1–10 months), one patient had grade 1, eight patients had grade 2, nine patients had grade 3, eight patients had grade 4, 13 patients had grade 5, seven patients had grade 6, and 11 patients had grade 7. Six patients died from aspiration pneumonia (one before, three during, and two post-treatment), and did not have the second MBS. Overall, 37/63 (59%) patients developed aspiration, six of them (9%) fatal. If we excluded the 10 patients who had severe aspiration at diagnosis and the six patients who died from pneumonia, the prevalence of severe aspiration was 33% (21/63). Conclusions Aspiration remained a significant morbidity following chemoradiation for head and neck cancer. Its prevalence is underreported in the literature because of its often silent nature. Diagnostic studies such as MBS should be part of future head and neck cancer prospective studies to assess the prevalence of aspiration, and for rehabilitation.

6024Background: Therapeutic de-intensification for OPC underscores the need for accurate patient-specific assessment of risk. Current risk stratification is based on HPV tumor status, tobacco use, ...

The aim was to assess the influence of treatment, tumor stages and sites on the severity of dysphagia following treatment. Sequential modified barium swallow (MBS) examinations were performed in patients who complained of chronic dysphagia following treatment of their head and neck cancer. Patients were selected if they were cancer free at their last MBS and had 2 or more MBS studies. Dysphagia severity was graded on a scale of 1 to 7. Dysphagia grade was compared between the first and last MBS to assess its evolution. Between 1996 and 2005, 63 patients with chronic dysphagia underwent MBS to assess dysphagia severity for nutritional support. Twenty-one patients (33%) had improvement of their dysphagia. Two of these patients (3%) achieved normalization of the swallowing. Twenty-five patients (40%) had no change of the dysphagia severity. Dysphagia grade increased in 17 patients (27%). Analysis of patient characteristics did not show any significant difference between these three groups of patients. MBS is a useful tool to monitor dysphagia severity and to identify aspiration risk. Stages of disease and treatment modality do not seem to impact on the course of dysphagia.

To assess the feasibility and effectiveness of combined therapy on locally advanced cervical cancer, we entered 38 patients into a study. The patients were treated with mitomycin-C (10 mg/m2) on Days 1 and 30 and 5-FU (1000 mg/m2) on Days 1 to 4 and Days 30 to 33. In 5 weeks 4500-5000 cGy was given concurrently, followed by radioactive implants. Twenty-six patients had an early-stage disease (IB-IIB) and twelve had a late-stage disease (IIIB-IVA). Eighty-seven percent (33/38) of the patients had a tumor measuring 5 cm or more. The other 5 patients with a tumor size under 5 cm had biopsy-proven positive pelvic nodes; 2 of these 5 patients had a pretherapy hysterectomy. Tumor response, complete (CR) vs partial (PR), was assessed in 36 patients 3 months after completion of therapy. A CR was noted in 80% (29/36) of the patients. The PR status conferred a detrimental effect on the pelvic disease control (PDC), disease-free survival (DFS), and survival (S) while late stage correlated with the development of distant metastases (DM) and a poor DFS. PDC was obtained in 93% (27/29) of the patients who had a CR, as compared to only 43% (3/7) of those with a PR (P = 0.0228). The DFS and S rates were 59 and 77% for patients with a CR and 21 and 19% for those with a PR; respective P values were 0.0340 and 0.0002. Eleven percent (3/26) of the patients with an early stage developed DM, as compared to 50% (6/12) of those with late stage, (P = 0.0016). The DFS rates were 80 and 37% for patients with an early and late stage, respectively (P = 0.0141). Four patients developed transient neutropenia and one had transient thrombocytopenia. The second dose of mitomycin-C was omitted in 4 patients due to persistent neutropenia in 3 and to transfusion-related hepatitis in 1. Two percent (5/21) of the patients who had a staging laparotomy developed wound dehiscence. Three patients developed non-cancer-related small bowel obstruction requiring surgery. We concluded that this combined regimen was well tolerated. Although it was effective in controlling the cancer in the pelvis, this regimen failed to control DM in late-stage patients.

To assess the risk of developing aspiration during chemoradiation for head and neck cancer.A retrospective review of 114 patients who underwent concurrent chemoradiation for locally advanced head and neck cancer was undertaken. Patients were determined as having aspiration if they had pneumonia on chest-X-ray (CXR) and/or had documented aspiration on the modified barium swallow (MBS) during their treatment.Fifteen patients (13%) developed aspiration during chemoradiation. Twelve patients (10%) had aspiration demonstrated on CXR alone (9 patients) or combined with MBS (3 patients). Three patients (3%) had aspiration on MBS alone. Three of the six patients with aspiration observed on MBS had normal swallowing on their pretreatment MBS. All 15 patients had severe mucositis and neutropenia at the time of the aspiration. Despite broad-spectrum antibiotics and supportive care, six patients (5%) died.Aspiration may develop during chemoradiation for head and neck cancer because of radiation-induced altered swallow.

The aim of this study was to evaluate the aspiration rate following nonsurgical therapy, i.e. chemoradiation or radiation alone for laryngeal cancer. Modified barium swallow was performed in 43 patients who complained of dysphagia following chemoradiation (n = 22) or radiation alone (n = 21) for laryngeal cancer. Patients were selected if they were cancer free at the time of the swallowing study. Dysphagia severity was graded on a scale of 1–7. Patients were grouped according to the dysphagia severity: no aspiration (grade 1–4), and severe (grade 5–7). Mean and median dysphagia grades were 4.4/5 and 3.5/3 for chemoradiation and radiation, respectively. Aspiration occurred in 12 patients (54%) of the chemoradiation group and 7 (33%) of the radiation alone group (p = 0.13). There was a higher proportion of patients with large tumor (T3–T4) in the chemoradiation group (64%) compared to the radiation group (5%) (p = 0.0001). Aspiration is a significant source of morbidity in patients treated for laryngeal cancer with chemoradiation or radiation alone. Aspiration occurred in both groups. Although the observed difference in aspiration rates did not achieve statistical significance, the higher aspiration rate in the chemoradiation group may be due to a higher proportion of large tumors, to the additional toxic effect of chemotherapy, or to the small number of patients in both groups. Diagnostic studies such as modified barium swallow should be part of future laryngeal cancer prospective studies to assess the prevalence of aspiration as it may be silent.

This study examines the efficacy of swallowing therapy in cancer-free patients who developed aspiration following treatment for locally advanced head and neck cancer. The records of 41 patients who underwent swallowing therapy for aspiration were reviewed. All patients were cancer free at a median follow-up of 25 months (6-150 months). Their treatment were respectively chemoradiation (24), and postoperative radiation (17). All patients had two or more modified barium swallow (MBS). Dysphagia severity was graded from 1 to 7. Dysphagia grade was compared before and following swallowing therapy. Before swallowing therapy, there were 16 grade 5 (trace aspiration), and 25 grade 6-7 (severe aspiration). In the chemoradiation group, there were nine grade 5, five grade 6, and 10 grade 7. Corresponding numbers for the postoperative group were: seven grade 5, seven grade 6, and three grade 7. Following swallowing therapy, there were six grade 3, seven grade 4, 10 grade 5, six grade 6, and 12 grade 7. In the chemoradiation group, there were four grade 3, three grade 4, four grade 5, five grade 6, and eight grade 7. In the postoperative group, there were two grade 3, four grade 4, six grade 5, one grade 6, and four grade 7. Overall, 13 patients (32%) had improvement of their dysphagia severity. Seven of them were in the chemoradiation group (29%), and six (35%) were in the postoperative group. Among 25 patients who presented with grade 6-7 aspiration, only nine (36%) improved to grade 5 or less. Four of them (27%) were in the chemoradiation group, and five (29%) were in the postoperative group. Swallowing therapy is effective to improve dysphagia severity and reduce the need for tube feedings. However, a significant number of patients still suffered from chronic severe aspiration. New strategies must be devised to improve their outcome.

Objective The purpose of the study is to evaluate dysphagia severity following chemoradiation and postoperative radiation for head and neck cancer, and particularly the aspiration risk because of its potential life-threatening consequence. Materials and methods We reviewed retrospectively the modified barium swallow (MBS) results in 110 patients who complained of dysphagia following chemoradiation (57) and postoperative radiation (53) of their head and neck cancer. Patients were selected if they were cancer free at the time of the swallowing study. Dysphagia severity was graded on a scale of 1–7. Patients were grouped according to the dysphagia severity: mild (grades 2–3), moderate (grades 4–5), and severe (grades 6–7). Results Mean and median dysphagia grades were 4.84/5 and 4.12/4 for chemoradiation and postoperative radiation respectively. The mean difference between the two groups is statistically significant ( p = 0.02). Mild dysphagia occurred in 13 patients (22%) of the chemoradiation group and 17 (32%) of the postoperative group. Corresponding number for the moderate group was 25 (43%) and 25 (48%), respectively. Severe dysphagia was significant in the chemoradiation group (34%) compared to the postoperative group (19%). However, the difference was not statistically significant ( p = 0.29). There was a higher proportion of patients with large tumor (T3–T4) in the chemoradiation group who developed severe dysphagia. Conclusion Dysphagia remained a significant morbidity of chemoradiation and postoperative radiation for head and neck cancer. Dysphagia may be more severe in the chemoradiation group because of the higher proportion of patients with large tumor, the high radiation dose, and a high number of oropharyngeal tumors. Aspiration occurred in both groups. Diagnostic studies such as MBS should be part of future head and neck cancer prospective studies to assess the prevalence of aspiration, as it may be silent.

The purpose of this investigation was to evaluate chronic dysphagia (lasting 3 or more months) following treatment for head and neck cancer. Since dysphagia is a common sequela post therapy in cancer survivors, it may be helpful for the clinician to be aware of the persistence of dysphagia as well as its usual severity. Modified Barium Swallow (MBS) examinations were performed in cancer-free patients who complained of dysphagia following treatment for head and neck cancer. The severity of the dysphagia was graded on a scale of 1 to 7. Each patient had sequential MBS and underwent swallowing therapy in between. The severity of dysphagia was compared between the first and last MBS study to determine whether the swallowing function had returned to normal.Between 1996 and 2004, 12 patients with dysphagia underwent repeated MBS following treatment. Swallowing function did not return to normal in all patients. At a median time of 29 months following treatment (range 8 to 94 months), the severity of dysphagia decreased in 8 patients (67%), remained unchanged in 3 patients (25%) and worsened in 1 patient (8%). Chronic dysphagia following treatment is unlikely to resolve with time despite rehabilitation therapy. Excessive scarring following treatment may be responsible for the persistence and severity of dysphagia. Physicians should be aware of the long-term effects of dysphagia on patient nutrition and psychological well-being.

Objectives Standard primary treatment for locally advanced cervix cancer is radiation (RT) with concomitant platinum-based chemotherapy (CT). Incomplete local control and the appearance of distant disease herald poor survival and warrant evaluation of new primary strategies. Paclitaxel and carboplatin are active agents in recurrent cervical carcinoma, have potent, synergistic in vitro radiosensitization, and are cytotoxic in weekly schedules. This study was done to determine the maximum tolerated dose (MTD) and dose-limiting toxicity (DLT) of weekly paclitaxel/carboplatin chemoradiotherapy in locally advanced cervix cancer. Methods Women with primary, previously untreated, squamous cell or adenocarcinoma of the cervix, FIGO stage IB 2 to IVA, negative para-aortic lymph nodes, adequate organ function and performance status were eligible. Pelvic RT (45 Gy over 5 weeks—180 cGy/day, four-field) was followed by two brachytherapy applications (Point A low dose rate (LDR): 90 Gy, high dose rate (HDR): 75 Gy). Concurrent weekly CT was paclitaxel 50 mg/m 2 and carboplatin, starting at AUC 1.5 and escalating in three-patient cohorts by AUC 0.5 (Max AUC 3.5). Dose escalation followed a 4-week observation period for toxicity. A grade III–IV toxicity prompted up to three additional patients per dose level. A second event defined DLT. CT was administered concurrently throughout brachytherapy. Results Fifteen patients were enrolled and treated over four dose levels until DLT was reached. Median age was 44 years (range, 23–70); stages: IB2: 1, IIB: 9, IIIA: 1, IIIB: 4. Median RT treatment time was 61 days (range, 55–79). Fourteen patients received brachytherapy (LDR: 8, HDR: 6), and one received external RT only due to cervical stenosis. The median number of weekly CT cycles was seven (range, 6–7). One CT dose was dropped in one patient for a grade II thrombocytopenia. One grade III ANC was observed at dose level II (AUC 2.0) but not seen in three additional patients. At dose level IV (AUC 3.0), two grade III–IV ANC toxicities were observed in two patients (DLT). Nine patients had grade II anemia. One patient had grade III anemia. Grade III/IV nonhematologic toxicity was rare (1/15 GI-nausea/vomiting, 1/15 pneumonia, 1/15 hypokalemia). The MTD of carboplatin is AUC 2.5 with paclitaxel 50 mg/m 2 . Median follow-up is 17 months; three patients have recurred and two have died. The estimated 2-year PFS and OS are 80% and 86%. Conclusions Weekly paclitaxel and carboplatin chemoradiation is feasible and active. The MTD for a phase II trial is 50 mg/m 2 and AUC 2.5, respectively.

Intraoperative radiation therapy (IORT) and interstitial radiotherapy (brachytherapy) are highly effective adjunctive treatments for head and neck cancer. The radiotolerance of the carotid artery, pharynx, and mandible to therapeutic doses of these modalities, however, has not been clearly established. To investigate the effects of IORT and interstitial iridium 192 (192Ir) on these structures in the canine, both sides of the neck of 12 mongrel dogs were operated on to expose 4-cm segments of the common carotid artery, pharynx, and mandible. One side of the neck was irradiated in each animal with the opposite side serving as the unirradiated control. The animals were divided into 3 groups of 4 dogs each. The first group received 40-Gy IORT and the second, 60-Gy IORT. In the third group of animals, afterloading catheters were implanted followed by placement of 60-Gy 192Ir. At 2 and 4 months after irradiation, 2 dogs in each treatment group were killed and histopathologic examination of the carotid artery, pharynx, and mandible was performed using hematoxylin-eosin staining. No statistically significant difference between treatment groups was found for carotid artery injury, but a trend for the proportion of fibrosis of the carotid on the irradiated side to increase with dose (P = .125) and time (P = .250) was noted. No apparent or statistically significant difference was found between treatment groups for pharyngeal injury. The greatest histologic changes noted following IORT and 192Ir brachytherapy were found in mandible specimens. The incidence of bone marrow suppression in irradiated mandible specimens versus controls approached statistical significance (P = .062). Osteoradionecrosis (ORN) was noted in the irradiated mandible specimens of two dogs, one of which received 60-Gy IORT and the other 60-Gy interstitial 192Ir. This manuscript reviews animal and clinical investigations relevant to the use of IORT and interstitial radiotherapy to the head and neck. Recommendations are made regarding further animal and clinical research as well as methods of treatment.

The Syed-Neblett perineal template has been in use at our institution since 1984. We have occasionally encountered problems in inserting the needles through the peripheral rows of the template and have seen significant convergence of the needles cephalad to the template. To solve these problems we have modified the Syed-Neblett template. In the new design, the entrance holes are closer together than in the original template, but they are angled so as to achieve a more compact design while maintaining a dose distribution close to that of the Syed-Neblett design. We have seen significantly fewer clinical problems with this design. In addition, a smaller number of needles achieve the same dose distribution; this simplifies their visualization on radiographs.