bluuebunny/crossref_metadata_2025_split huggingface dataset:
The treatment of early laryngeal cancers (T1–T2 N0): surgery or irradiation?
Authors: Jones Andrew Simpson , Fish Brian , Fenton John Eugene , Husband David John 
Published: January 2004

AbstractBackground.Carcinoma of the larynx is the most common cancer affecting the head and neck region. In Northern Europe, early laryngeal cancer is almost universally treated by irradiation, but elsewhere it is treated by surgery. The main aim of this study was to determine whether there was any difference in survival between the two main therapeutic options. The secondary aim was to assess speech and voice quality in a small, randomized sample of patients from each treatment group.Methods.The subjects investigated were 488 patients with T1–2, N0 squamous cell carcinoma of the larynx. The patients form an unselected sequential group of our institution's experience with treating this disease over three decades. Four hundred nineteen patients were treated by irradiation, and 69 were treated with surgery. Most surgical patients were treated earlier in the series, whereas radiotherapy later became the treatment of choice. The primary outcome measures were recurrence at the primary site, recurrence in the neck, and tumor‐specific survival. The secondary outcome measure was speech and voice quality. Statistical analysis was by univariate and multivariate analysis of association and survival. Surgery included horizontal or vertical partial laryngectomy and various minor procedures on the glottis, including cordectomy. Over a 30‐year period, radiotherapy was administered to a dose of 60–66 Gy given over 30–33 daily fractions.Results.Surgery tended to be performed early on in the series and radiotherapy thereafter. Surgery was more likely to be carried out for supraglottic disease. These differences apart, the radiotherapy and surgery groups of patients were well matched. The 5‐year tumor‐specific survival for those treated by irradiation was 87% and for surgery it was 77% (p= .1022). Glottic cancer and T1 disease were associated with high 5‐year survivals: 90% and 91%, respectively. Supraglottic site and T2 disease both had a poorer prognoses: 79% and 69%, respectively. The differences for both sets of data were significant. There was no significant difference in primary site recurrence rates for the two treatment modalities, but regional recurrence was higher in the surgery group. Further analysis demonstrated that this was not a function of surgery per se but rather of the unit's policy toward the N0 neck at the time surgery was carried out. Regarding speech and voice quality, radiotherapy was far superior to surgery. All patients in the radiotherapy group but only 3 of 10 in the surgery group were judged to have a good or normal voice (p= .0017).Conclusions.Both surgery and irradiation are equally effective at treating early laryngeal carcinoma. Speech and voice were highly significantly better in patients treated by irradiation than in those treated by surgery. © 2004 Wiley Periodicals, Inc.Head Neck26:127–135, 2004
Predictive values for aspiration after endoscopic laser resections of malignant tumors of the hypopharynx and larynx
Authors: Bernal‐Sprekelsen Manuel , Vilaseca‐González Isabel , Blanch‐Alejandro Jose‐Luis 
Published: January 2004

AbstractBackground.CO2‐laser surgery is a relatively new treatment for selected carcinomas of the upper aerodigestive tract. The purpose of our study was to evaluate prospectively the functional results for swallowing after C02‐laser resections.Methods.The sample was composed of 210 consecutive patients with malignancies of the larynx and hypopharynx treated with CO2 laser between February 1998 and January 2002. Endoscopic resections included all T1 and T2 tumors and selected T3 and T4 tumors. T1 glottic tumors were not included in the analysis. We assessed the need for a feeding tube and the period the tube remained in place, aspiration pneumonia, tracheotomy secondary to aspiration, the need for a permanent or temporary gastrostomy, and total laryngectomy secondary to aspiration.Results.The nasogastric feeding tube was used in 23.2% of small tumors (2.5 ± 8.04 days) and in 63% of locally advanced tumors (13.95 ± 22.55 days). Frequency and period of storage of the feeding tube were higher in locally advanced tumors (p = .0001). Twelve patients (5.7%) had postoperative pneumonia and 59 (28.1%) had temporary postoperative cough during oral intake. Aspiration symptoms correlated with location (p = .001) and locally advanced tumors (p = .016). Eight patients (3.8%) needed a postoperative tracheotomy for severe swallowing difficulties; six (2.9%) of them were definitive and two (0.95%) temporary. Thirteen gastrostomies (6.2%) were performed to avoid severe aspirations; five of them were definitive. The need for gastrostomy correlated significantly with location (p = .002), pT3 and pT4 tumors (p = .002), age (p = .02), and postoperative radiotherapy (p = .04). No correlation was found with the period of feeding tube (p = .38), or aspiration pneumonia (p = .24).Conclusions.Endoscopic resection of laryngeal and hypopharyngeal tumors is associated with good recovery of deglutition. Many tracheotomies are avoided, the need for a feeding tube is usually reduced, and organ preservation is often feasible even in locally advanced tumors. © 2003 Wiley Periodicals, Inc. Head Neck 26: 103–110, 2004
Single‐stage surgical repair of benign laryngotracheal stenosis in adults
Authors: van den Boogert Jolanda , Hans Hoeve L. J. , Struijs Ard , Hagenouw René R. P. M. , Bogers Ad J. J. C. 
Published: January 2004

AbstractBackground. Benign laryngotracheal stenosis causes considerable morbidity. In a retrospective study, we describe the results of our surgical treatment.Methods. Between June 1999 and June 2002, 14 adults with laryngotracheal stenosis were referred to our hospital. Stenosis resulted from mechanical ventilation in 11 patients, from Wegener's granulomatosis in 2 patients, and from strangulation in 1 patient. Eleven patients had a tracheotomy. One patient was found unfit for surgery. Nine patients underwent cricotracheal resection (CTR) with end‐to‐end anastomosis, and four patients underwent single‐stage laryngotracheoplasty (SS‐LTP) without stenting.Results. There were no perioperative deaths. Patients were extubated after mean of 3 days (range, 0–10 days; CTR 2.3 days vs SS‐LTP 3.5 days, p = .45). There were in‐hospital complications in five patients. Mean hospital stay was 19 days (range, 8–53 days; after CTR 24 days vs SS‐LTP 9 days, p = .015). With regard to airway patency and voice recovery, 10 patients (77%) had good results, including 1 patient with two readmissions, and 3 (23%) had satisfactory results, including 1 patient with 11 additional nonsurgical interventions.Conclusions. Benign laryngotracheal stenosis in the adult patient can be repaired successfully using a strategy of two single‐stage surgical procedures. All patients had good or satisfactory functional results. A multidisciplinary approach was essential to achieve these good results. © 2004 Wiley Periodicals, Inc. Head Neck 26: 111–117, 2004
Technique of endoscopic retrograde puncture and dilatation of total esophageal stenosis in patients with radiation‐induced strictures
Authors: Lew Ronald J. , Shah Janak N. , Chalian Ara , Weber Randal S. , Williams Noel N. , Kochman Michael L. 
Published: January 2004

AbstractBackground.Complete esophageal stenosis can occur after external beam radiation therapy for malignancies. Treatment for this complication has traditionally involved surgery.Methods.A new technique to reestablish luminal patency is described. This minimally invasive technique involves retrograde endoscopy by means of gastrostomy tube tract and puncture of the stenotic occlusion followed by stricture dilatation. The procedure is performed under combined endoscopic and laryngoscopic guidance.Results.Five consecutive patients who had complete esophageal stenoses develop after radiation therapy for malignant disease underwent retrograde endoscopy by way of gastrostomy tube tracts. Stenoses were punctured under endoscopic and laryngoscopic guidance with guide wires. Strictures were dilated with wire‐guided balloons or polyvinyl dilators. Luminal patency was established in all patients using this technique without procedural complications.Conclusions.Endoscopic retrograde puncture and dilatation of total esophageal stenoses is safe, effective, and useful to reestablish luminal patency for radiation‐induced strictures. This technique should be attempted before more invasive treatments. © 2004 Wiley Periodicals, Inc. Head Neck 26: 179–183, 2004
Radiotherapy alone or combined with surgery for adenoid cystic carcinoma of the head and neck
Authors: Mendenhall William M. , Morris Christopher G. , Amdur Robert J. , Werning John W. , Hinerman Russell W. , Villaret Douglas B. 
Published: January 2004

AbstractPurpose.The purpose of this study was to analyze the results of radiotherapy (RT) alone or combined with surgery for adenoid cystic carcinoma.Methods.Between September 1966 and November 2001, 101 previously untreated patients were treated with curative intent with RT alone or combined with surgery. Follow‐up ranged from 0.4–30.6 years (median, 6.6 years). All living patients had follow‐up for at least 1 year.Results.The 5‐ and 10‐year rates of local control were as follows: RT alone, 56% and 43%; surgery and RT, 94% and 91%; and overall, 77% and 69%. Multivariate analysis of local control revealed that T stage (p= .0101) and treatment group (p= .0008) significantly influenced this endpoint. The 5‐ and 10‐year rates of distant metastases‐free survival were 80% and 73%. The 5‐ and 10‐year absolute survival rates were as follows: RT alone, 57% and 42%; surgery and RT, 77% and 55%; and overall, 68% and 49%. Multivariate analysis of absolute survival revealed that T stage (p= .0043) and clinical nerve invasion (p= .0011) significantly influenced this endpoint. The 5‐ and 10‐year cause‐specific survival rates were as follows: RT alone, 65% and 48%; surgery and RT, 81% and 71%; and overall, 74% and 61%. Multivariate analysis revealed that T stage (p= .0008) and clinical nerve invasion (p= .0005) significantly influenced cause‐specific survival.Conclusions.The optimal treatment for patients with adenoid cystic carcinoma is surgery and adjuvant RT. A significant proportion of patients with incompletely resectable disease are cured after RT alone. Improvements in locoregional control are offset, in part, by the relatively high incidence of distant metastases. © 2004 Wiley Periodicals, Inc.Head Neck26:154–162, 2004
Seasonal transpiration pattern of Phragmites australis in a wetland of semi‐arid Spain
Authors: Moro María José , Domingo Francisco , López Germán 
Published: January 2004

AbstractTranspiration rates were measured in a flooded population of Phragmites australis ssp. altissima in a wetland located in ‘El Hondo’ Natural Park (southeastern Spain) during the growing season of 2000. The heat balance method for measuring sap flow was used to calculate the rate of water transpiration on a whole‐stem basis. Four series of measurements were carried out in selected weeks in May, June, August and October. Structure, biomass and leaf area index of the reed population were simultaneously quantified in order to scale transpiration on a plot‐area basis.Overall, transpiration flux was high during the sampling period and showed a typical diurnal pattern with a maximum at about midday. Mean transpiration was highest at the end of June coinciding with the peak of reed growth and with the maximum leaf area both at individual and plot scales. Rates decreased abruptly in October, in parallel with the advanced foliar senescence. The variation of both midday and integrated daily transpiration is significantly related to that of the air temperature on clear days. Cloudy and rainy days exert a pronounced effect on water loss by decreasing transpiration. Our results highlight the potential use of the sap‐flow method to measure transpiration in reed ecosystems and the relevance of this flux for the water balance in wetlands in semi‐arid environments. Thus, it is suggested that water management in these areas could be favoured by acquiring high‐quality experimental data. Copyright © 2004 John Wiley & Sons, Ltd.
Hydraulic conductivity of peat at Ellergower Moss, Scotland
Authors: Clymo R. S. 
Published: January 2004

AbstractFalling head (and a few rising head) measurements were made of hydraulic conductivity k in a profile of a 7 m deep, small raised bog in southwest Scotland. The seven piezometer pipes were 39 mm diameter, and most of the measurements were made with attached tubes of 2·5 mm diameter, so that only 2–3 mm of water crossed the peat interface during a run. There were no consistent effects of pre‐flushing, direction of flow (falling, rising), or measuring‐tube size. Variability of 10–20% in k did not obscure an exponential decrease with depth from 5 × 10−6 cm s−1 at 100 cm to 0·7 × 10−6 cm s−1 at 500 cm. This decrease was uncorrelated with dry bulk density or peat stiffness, and only loosely so with a measure of humification. Calculated mean bulk velocity of pore water may be as low as 1 mm year−1. Pressure in the silty sand below the peat was 180 mbar less than expected, suggesting a thin highly impermeable layer (‘pan’?) at the peat base. The substratum may have hydrological connection with an adjacent lake. The hydraulic properties of this raised bog contrast strongly with those of a raised bog in Minnesota, and do not fit the assumptions made for Ingram's simple groundwater mound model of raised bog shape. Copyright © 2004 John Wiley & Sons, Ltd.
An assessment of the piezometer method for measuring the hydraulic conductivity of a Cladium mariscus—Phragmites australis root mat in a Norfolk (UK) fen
Authors: Baird Andrew J. , Surridge Ben W. J. , Money Russ P. 
Published: January 2004

AbstractDespite their common global occurrence, little work has been done on characterizing the hydraulic properties of root mats, particularly their hydraulic conductivity K. A common method for estimating K in the field is the piezometer slug test. In some root mat systems, the piezometer slug test may be the only technique, field or laboratory, that is able to provide reliable estimates of K. We installed 17 piezometers in a Cladium mariscus L. (Pohl) and Phragmites australis Cav. (Streud.) root mat in a UK fen. Tests were initiated by both slug insertion and slug withdrawal. Repeat tests were conducted on some piezometers to check for test consistency. Rapid recoveries after both slug insertion and withdrawal were found, with 90% recovery reached for all tests within 1500 s and for many within 300 s. We found significant and highly reproducible differences between recovery after insertion and recovery after withdrawal, with the latter being more rapid than the former. We invoke a reversible pore blocking mechanism to explain this behaviour. Many of the piezometers showed recoveries after withdrawal that were broadly consistent with the assumption of a rigid porous medium in which Darcy's law holds. Tests on four further piezometers were used to examine the impact of piezometer ‘development’, different slug sizes and the use of ‘clean’ water on test behaviour. The results from these test piezometers were difficult to interpret. Nevertheless, it appears that replacing ‘dirty’ water in the piezometer standpipe with clean water leads to more rapid recoveries and reduces the difference between recovery after insertion and recovery after withdrawal. The K of the root mat, as estimated from withdrawal tests on 14 piezometers and standardized to 20°C, ranged between 0·00144 and 0·03022 cm s−1. This appears to be at the very top end of K values reported for fen peats and suggests that water can flow readily through this medium given sufficiently large hydraulic gradients. Copyright © 2004 John Wiley & Sons, Ltd.
Numerical modelling of groundwater flow and contaminant transport to Point Pelee marsh, Ontario, Canada
Authors: Crowe Allan S. , Shikaze Steven G. , Ptacek Carol J. 
Published: January 2004

AbstractA numerical model was developed for simulating groundwater–wetland interactions and contaminant transport. The model calculates transient hydraulic head and a transient free surface in a two‐dimensional, heterogeneous domain, with variable and transient boundary conditions (infiltration, evapotranspiration, surface water), and water and contaminant fluxes across the aquifer–wetland interface. Contaminant transport is also simulated, with contaminant sources located at the free surface, wetland, or within the saturated domain. The model was applied to assess groundwater–wetland interactions and the transport of septic‐system‐derived contaminants at Point Pelee, Ontario, Canada. The model successfully simulated the field observations of groundwater flow and contaminant plumes. Where the barrier bar is narrow, the seasonal reversal in the direction of groundwater flow is caused by differences in the elevation of the water surface of Lake Erie and that of the marsh. This, in turn, induces the contaminants to oscillate between movement towards the lake during the winter and towards the marsh during the summer. Hence, contaminant plumes are bimodal in shape. Where the barrier bar becomes wider, the lake and the marsh have less effect, and hence contaminants move in one direction, along the principal direction of groundwater flow towards the marsh. Copyright © 2004 John Wiley & Sons, Ltd.
The influence of past and present hydrological conditions onSphagnumrecolonization and succession in a block‐cut bog, Québec
Authors: Price Jonathan S. , Whitehead Grant S. 
Published: January 2004

AbstractThis study of an abandoned cutover bog aims to understand the processes controlling moisture conditions that have led to distinct spatial patterns ofSphagnumrecolonization, and also how substrate conditions may have changed since abandonment and the implications for plant establishment. Two (unreplicated) symmetrical 12 × 3·5 m2quadrats either side of the centre‐line of a block‐cut trench were treated by removing all recolonized vegetation, includingSphagnum, from one quadrat (REMOV), examiningSphagnum‐covered (SPHAG) peat in the other, and bare peat (BARE) in both. Average volumetric soil moisture contents θ in the peat (2 cm below the surface) of the SPHAG and REMOV substrates were similar (∼86%), but greater than in BARE peat (∼78%). In a location not manipulated for this experiment, whereSphagnumcushions have re‐established on bare cutover peat, θ beneath the cushions was 5–14% greater than in bare cutover peat directly adjacent to it, indicating that cushions can regulate local substrate water storage, and benefit from it during periods of increased water demand. This may have assisted in the lateral expansion ofSphagnum. A loosely structured 0·5 to 1·0 cm thick organic litter layer (chiefly Ericaceae) overlying the BARE peat substrate slowed the rate of drying of bare peat in a laboratory sample. The laboratory tests found the capillary fringe to be up to 26 cm above the water table. The dry conditions and the larger pore structure of this litter layer hindered upward capillary flow and, therefore, plant water availability. In (occluded) ditches and low areas, the capillary fringe remained within 5 cm of the surface, and these locations supported the most completeSphagnumcover. In slightly higher areas, where the capillary fringe was about 20 cm below the surface, and because of the leaf litter, capillary water supply to the surface is sufficiently restricted to limitSphagnumrecolonization. These locations may have to await lateral expansion ofSphagnumcushions to achieve a full cover. Copyright © 2004 John Wiley & Sons, Ltd.
Soil aeration status in a lowland wet grassland
Authors: Barber K. R. , Leeds‐Harrison P. B. , Lawson C. S. , Gowing D. J. G. 
Published: January 2004

AbstractThe maintenance or development of plant community diversity in species‐rich wet grasslands has been a focus of water management considerations in the UK for the past 20 years. Much attention has been given to the control of water levels in the ditch systems within these wet grassland systems. In this paper we report measurements of aeration status and water‐table fluctuation made on a peat soil site at Tadham Moor in Somerset, UK, where water management has focused on the maintenance of wet conditions that often result in flooding in winter and wet soil conditions in the spring and summer. Measurement and modelling of the water‐table fluctuation indicates the possibility of variability in the aeration of the root environment and anoxic conditions for much of the winter period and for part of the spring and summer. We have used water content and redox potential measurements to characterize the aeration status of the peat soil. We find that air‐filled porosity is related to water‐table depth in these situations. Redox potentials in the spring were generally found to be low, implying a reducing condition for nitrate and iron. A significant relationship (p < 0·01) between redox potential and water‐table depth exists for data measured at 0·1 m depth, but no relationship could be found for data from 0·4 m depth. Copyright © 2004 John Wiley & Sons, Ltd.
Influence of hydrologic regime and vegetation on phosphorus retention in Everglades stormwater treatment area wetlands
Authors: White John R. , Ramesh Reddy K. , Moustafa M. Z. 
Published: January 2004

AbstractThe Florida (USA) Everglades ecosystem has been impacted due to increased loading of nutrients, in particular phosphorus (P), primarily from adjacent agricultural areas. Consequently, restoration measures involve the establishment of stormwater treatment areas (STAs) comprising a series of constructed wetlands. A series of mesocosms were established at the inflow of the Everglades Nutrient Removal Project wetland, the first such STA constructed. These mesocosms were designed to mimic STAs, as they operated as flow‐through systems and were packed with native soil. The objective of the study was to determine the effects of vegetation and hydrologic fluctuations on P retention/release by the wetland soil and on effluent water quality. Four treatment combinations consisted of continuously flooded with emergents (Typha), intermittently flooded with emergents, continuously flooded with no emergents, and intermittently flooded with no emergents. Intermittently flooded treatments underwent two 1 month drawdown events during the year. Soils were collected to determine the various pools of P and surface water samples were collected twice weekly to determine mass P flux in and out of the mesocosms. Results showed that the majority of the P was stored in the calcium‐ and magnesium‐bound fraction, as well as the refractory pool in the soil. Approximately 91% of the inflow soluble reactive P (SRP) mass was retained within the mesocosms for the continuously flooded treatment, and 80% was retained in the treatments subjected to periodic drawdown events, regardless of vegetation type. There was a net annual flux of dissolved organic P (DOP) out of the mesocosms for the drawdown treatments, whereas the net reduction in the DOP concentrations for the continuously flooded treatments was just 17%. These results demonstrate that, although these wetland systems perform well in reducing surface water SRP, additional research may need to focus on improving the reduction of DOP in order to reduce further the P loads to the nutrient‐sensitive Everglades system. Copyright © 2004 John Wiley & Sons, Ltd.