Systematic Implementation of Effective Quality Assurance Processes for the Assessment of Radiation Target Volumes in Head and Neck Cancer.

PURPOSE: Significant heterogeneity exists in clinical quality assurance (QA) practices within radiation oncology departments, with most chart rounds lacking prospective peer-reviewed contour evaluation. This has the potential to significantly affect patient outcomes, particularly for head and neck cancers (HNC) given the large variance in target volume delineation. With this understanding, we incorporated a prospective systematic peer contour-review process into our workflow for all patients with HNC. This study aims to assess the effectiveness of implementing prospective peer review into practice for our National Cancer Institute Designated Cancer Center and to report factors associated with contour modifications. METHODS AND MATERIALS: Starting in November 2020, our department adopted a systematic QA process with real-time metrics, in which contours for all patients with HNC treated with radiation therapy were prospectively peer reviewed and graded. Contours were graded with green (unnecessary), yellow (minor), or red (major) colors based on the degree of peer-recommended modifications. Contours from November 2020 through September 2021 were included for analysis. RESULTS: Three hundred sixty contours were included. Contour grades were made up of 89.7% green, 8.9% yellow, and 1.4% red grades. Physicians with >12 months of clinical experience were less likely to have contour changes requested than those with <12 months (8.3% vs 40.9%; P < .001). Contour grades were significantly associated with physician case load, with physicians presenting more than the median number of 50 cases having significantly less modifications requested than those presenting <50 (6.7% vs 13.3%; P = .013). Physicians working with a resident or fellow were less likely to have contour changes requested than those without a trainee (5.2% vs 12.6%; P = .039). Frequency of major modification requests significantly decreased over time after adoption of prospective peer contour review, with no red grades occurring >6 months after adoption. CONCLUSIONS: This study highlights the importance of prospective peer contour-review implementation into systematic clinical QA processes for HNC. Physician experience proved to be the highest predictor of approved contours. A growth curve was demonstrated, with major modifications declining after prospective contour review implementation. Even within a high-volume academic practice with subspecialist attendings, >10% of patients had contour changes made as a direct result of prospective peer review.

Randomized clinical trial of accelerated enhanced recovery after minimally invasive colorectal cancer surgery (RecoverMI trial).

BACKGROUND: Minimally invasive surgery (MIS) and enhanced recovery protocols (ERPs) have improved postoperative recovery and shortened length of hospital stay (LOS). Telemedicine technology has potential to improve outcomes and patient experience further. This study was designed to determine whether the combination of MIS, ERP and a structured telemedicine programme (TeleRecovery) could shorten total 30-day LOS by 50 per cent. METHODS: This was a phase II prospective RCT at a large academic medical centre. Eligible patients aged 18-80 years undergoing minimally invasive colorectal resection using an ERP were randomized after surgery. The experimental arm (RecoverMI) included accelerated discharge on postoperative day (POD) 1 with or without evidence of bowel function and a televideoconference on POD 2. The control arm was standard postoperative care. The primary endpoint was total 30-day LOS (postoperative stay plus readmission/emergency department/observation days). Secondary endpoints included patient-reported outcomes measured by EQ-5D-5L™, Brief Pain Inventory (BPI) and a satisfaction questionnaire. RESULTS: Thirty patients were randomized after robotic (21 patients) or laparoscopic (9) colectomy, including 14 patients in the RecoverMI arm. Median 30-day total LOS was 28·3 (i.q.r. 23·7-43·6) h in the RecoverMI arm and 51·5 (43·8-67·0) h in the control arm (P = 0·041). There were no differences in severe adverse events or EQ-5D-5L™ score between the study arms. The BPI revealed low pain scores regardless of treatment arm. Satisfaction was high in both arms. CONCLUSION: In patients having surgery for colorectal neoplasms, the trimodal combination of MIS, ERP and TeleRecovery can reduce 30-day LOS while preserving patients' quality of life and satisfaction. Registration number: NCT02613728 ( https://clinicaltrials.gov).

ANTECEDENTES: La cirugía mínimamente invasiva (minimally invasive surgery, MIS) y los protocolos de recuperación intensificada (enhanced recovery protocols, ERP) han mejorado la recuperación postoperatoria y acortan la duración de la estancia (length of stay, LOS). La tecnología de la telemedicina tiene potencial para mejorar aún más los resultados y la experiencia del paciente. Este estudio se diseñó para determinar si la combinación de MIS, ERP y un programa estructurado de telemedicina (TeleRecovery) podría acortar la LOS total a los 30 días en un 50%. MÉTODOS: Se efectuó un ensayo controlado aleatorizado, prospectivo, de fase II en un gran centro médico académico. Los pacientes elegibles de 18-80 años de edad que se sometieron a resección colorrectal MIS mediante ERP se asignaron al azar después de la resección quirúrgica. El brazo experimental (RecoverMI) incluyó el alta acelerada en el día 1 del postoperatorio (postoperative day, POD) con o sin evidencia de recuperación del tránsito intestinal y una televideoconferencia en el día 2 POD. Los pacientes en el grupo control recibieron los cuidados postoperatorios habituales. El criterio de valoración principal fue la LOS total (estancia postoperatoria más reingreso/estancia en urgencias/días de observación) a los 30 días. Los criterios de valoración secundarios incluyeron los resultados referidos por los pacientes medidos por los cuestionarios EQ-5D-5L, el Cuestionario Breve del Dolor (Brief Pain Inventory, BPI) y un cuestionario de satisfacción. RESULTADOS: Treinta pacientes fueron aleatorizados después de una colectomía robótica (21) o laparoscópica (9), incluidos 14 pacientes en el grupo de RecoverMI. La mediana de la LOS total a los 30 días fue de 28,3 horas (rango intercuartílico, RIQ 23,7-43,6) en el grupo de RecoverMI y de 51,5 horas (RIQ 43,8-67,0) en el grupo control (P = 0,04). No hubo diferencias entre los grupos de estudio en los eventos adversos graves o en las puntuaciones del EQ-5D-5L. El BPI mostró puntuaciones bajas de dolor independientemente del grupo de tratamiento. La satisfacción fue alta en ambos grupos. CONCLUSIÓN: Entre los pacientes que se someten a cirugía por cáncer colorrectal, la combinación trimodal de MIS, ERP y TeleRecovery puede reducir la LOS a los 30 días, preservando la calidad de vida y la satisfacción del paciente.

SU-E-T-581: Planning Evaluation of Step-And-Shoot IMRT, RapidArc and Helical TomoTherapy for Hippocampal-Avoidance Whole Brain Radiotherapy (HA-WBRT).

PURPOSE: Several planning strategies are available for hippocampal- avoidance whole-brain radiotherapy (HA-WBRT) following RTOG protocol 0933, but have yet to be compared on a common set of patient data. In this inter-institutional investigation, we evaluate three modalities likely to be employed by protocol participants; step-and-shoot IMRT, volumetric modulated arc therapy, and helical tomotherapy. A common set of patients is used for comparison, including credentialing and successfully accrued patients. METHODS: Eight patient datasets were selected and de-identified prior to planning. Structures were contoured by physicians per protocol using fused MRI datasets. Three plans were generated for each dataset: Philips Pinnacle 9-field non-coplanar IMRT using protocol recommended beam parameters, Varian's RapidArc using two coplanar arcs, and Accuray's TomoTherapy using a 1cm jaw width. With the goal of meeting the compliance criteria outlined in RTOG 0933 (target coverage and dose limits to the hippocampus and optic structures), three planners independently planned each modality without prior knowledge of the patient's other plans to reduce bias. The three plans for each patient were compared according to the protocol's dosimetric compliance criteria. A homogeneity index was also computed to compare target dose uniformity. RESULTS: All plans achieved the protocol dose criteria, except for one RapidArc plan with slightly inferior dose to the optic chiasm. TomoTherapy offered superior dose homogeneity for all patients. For the two linac based methods, RapidArc was found to provide dose homogeneity at least as good as, and in most cases superior to, 9-field step-and-shoot IMRT. CONCLUSIONS: Helical TomoTherapy offers superior dose homogeneity for HA-WBRT following RTOG 0933. Compared to step-and-shoot IMRT, volumetric modulated arc techniques, such as RapidArc, can offer improved homogeneity for HA- WBRT and are generally more efficient/expeditious to deliver than the noncoplanar 9-field arrangement recommended by the protocol, which uses 7 separate couch angles.

SU-E-T-436: Feasibility of Using the 'Irregular Surface Compensator' Planning Feature of the Eclipse TPS for Total Body Irradiation (TBI) Treatment Planning.

PURPOSE: To investigate the feasibility of using the Irregular Surface Compensator (ISC) planning feature of the Eclipse treatment planning system (TPS) for Total Body Irradiation (TBI). METHODS: TBI treatments require that the whole body receives within +-10% of the prescribed dose. Different body parts with different thicknesses compared to the umbilicus separation may receive higher or lower doses compared to the prescribed dose. Another challenge is to keep the lung dose below 10Gy to avoid complications. To mitigate this problem, physical compensators and blocks are used during the treatment for different body parts and lungs. This method presents a challenge during the treatment delivery and prolongs the treatment time due to patient setup, in-vivo on-line dosimetric monitoring and the adjustment of the compensators frequently during the treatment. We investigated the use of ISC planning feature of Eclipse TPS which is an electronic compensation method that calculates a fluence map based on the body contour from the CT image. The fluence map is delivered with dynamic MLCs . This TBI treatment technique was tested using a Rando phantom in Head First Supine position with lateral beams at SSD=250cm.The calculated fluence were edited so that the lung received <∼10Gy for 12Gy prescription. A single fraction of 2Gy was delivered and the in-vivo measurements were performed in the neck, lung and the umbilicus by using OSLDs. RESULTS: OSLD measurements and the Eclipse TPS predictionswere 200.4/195.0, 162.2/168.9, and 196.1/208.9 cGy for the neck, lung and the umbilicus respectively. CONCLUSIONS: The feasibility of using the 'Irregular Surface Compensator' feature of Eclipse TPS for TBI treatment planning was demonstrated. Good agreement (<6%) between the predicted and measured doses was obtained. The proposed planning and delivery simplifies the compensation and blocking to achieve uniform dose distributions and reduces the treatment time.

Radiation damage, repopulation and cell recovery analysis of in vitro tumour cell megacolony culture data using a non-Poissonian cell repopulation TCP model.

The effects of radiation damage, tumour repopulation and cell sublethal damage repair and the possibility of extracting information about the model parameters describing them are investigated in this work. Previously published data on two different cultured cell lines were analysed with the help of a tumour control probability (TCP) model that describes tumour cell dynamics properly. Different versions of a TCP model representing the cases of full or partial cell recovery between fractions of radiation, accompanied by repopulation or no repopulation were used to fit the data and were ranked according to statistical criteria. The data analysis shows the importance of the linear-quadratic mechanism of cell damage for the description of the in vitro cell dynamics. In a previous work where in vivo data were analysed, the employment of the single hit model of cell kill and cell repopulation produced the best fit, while ignoring the quadratic term of cell damage in the current analysis leads to poor fits. It is also concluded that more experiments using different fractionation regimes producing diverse data are needed to help model analysis and better ranking of the models.

Prevalence of antibody to hepatitis A virus in drinking water workers and wastewater workers in Texas from 1996 to 1997.

To determine if wastewater workers had a higher prevalence of antibody to hepatitis A virus (anti-HAV) than drinking water workers, a convenience sample of Texas wastewater and drinking water workers was evaluated for risk factors by questionnaire and tested for anti-HAV. A total of 359 wastewater and 89 drinking water workers participated. Anti-HAV positivity was 28.4% for wastewater and 23.6% for drinking water workers. After adjustment for age, educational attainment, and Hispanic ethnicity, the odds ratio for the association between anti-HAV positivity and wastewater industry employment was 2.0 (95% confidence interval, 1.0 to 3.8). Among wastewater workers, never eating in a lunchroom, > or = 8 years in the wastewater industry, never wearing face protection, and skin contact with sewage at least once per day were all significantly associated with anti-HAV positivity in a model that adjusted for age and educational attainment. Wastewater workers in this study had a higher prevalence of anti-HAV than drinking water workers, which suggested that wastewater workers may have been at increased risk of occupationally acquired hepatitis A. Work practices that expose workers to wastewater may increase their risk.

Mercury poisoning associated with a Mexican beauty cream.

OBJECTIVES: To describe demographic characteristics, patterns of use, and symptoms associated with mercury poisoning among persons who used a Mexican beauty cream containing mercurous chloride and to estimate the prevalence of cream use in Texas near the Mexico border. DESIGN: Case series and cross-sectional survey. SETTING: Border communities of Arizona, California, New Mexico, and Texas. PARTICIPANTS: Persons who used the cream and contacted a health department in response to announcements about the cream and households that participated in the Survey of Health and Environmental Conditions in Texas Border Counties and Colonias, 1997. MAIN OUTCOME MEASURES: Urine mercury concentrations, self-reported symptoms, and prevalence of cream use among households. RESULTS: Of 330 cream users who contacted their health department, 96% were women, and 95% were Hispanic. The mean urine mercury concentration was 146.7 microg/L (reference range : 0-20 microg/L). In 5% of 2,194 randomly selected Texas households near the Mexico border, at least 1 person had used "Crema de Belleza-Manning" (Laboratorios Vida Natural, S.A., Tampico, Tamaulipas, Mexico) in the previous year. CONCLUSIONS: Most cream users had increased urine mercury concentrations. Cream use was common in Texas near the Mexico border. Physicians should consider toxicity in patients with neurologic symptoms of unclear cause and use public health departments when investigating unusual illnesses.

Group remembering: does social loafing underlie collaborative inhibition?

When people collaborate to recall information, they experience collaborative inhibition, a deficit in recall relative to nominal groups (the pooled, nonredundant recall of individuals working alone). That is, people recalling in groups do not perform up to their potential. Collaborative inhibition may be due to retrieval interference (e.g., B. H. Basden, D. R. Basden, S. Bryner, & R. L. Thomas, 1997) or to motivational factors such as social loafing in the group situation. Five experiments examined the role of motivational factors by varying monetary incentives, recall criterion, personal accountability, group cohesion, and group gender. Increasing motivation sometimes increased the overall level of recall but failed to eliminate the collaborative inhibition effect. The results suggest that collaboration interferes with an individual's ability to reconstruct his or her knowledge.

Identification of a promoter sequence from the BETL1 gene cluster able to confer transfer-cell-specific expression in transgenic maize

The maize (Zea mays L.) betl1 locus, encoding a basal endosperm transfer layer-specific protein, has been mapped and molecularly cloned in its entirety. The locus is shown to consist of three gene copies in the maize inbred line A69Y. To distinguish the three transcription units from the locus name, we have termed them BETL1a, BETL1b, and BETL1c. Two of the copies are expressed, whereas one is inactive and contains retrotransposon-like insertions in both promoter and intron regions. Based on this information, and a restriction site map covering 17 kb around the BETL1 locus, a DNA fragment putatively containing an active promoter sequence was identified. This fragment was tested for its ability to confer transfer-cell-specific expression in transient and stably transformed maize tissues. The transgenic maize plants obtained showed the predicted cell-type specificity of expression restricted to the basal endosperm transfer cells, although there were minor deviations in promoter strength and timing and accumulation of the transgene product from the corresponding BETL-1 endogene expression pattern.

An epidemic of congenital syphilis in Jefferson County, Texas, 1994-1995: inadequate prenatal syphilis testing after an outbreak in adults.

OBJECTIVES: After a syphilis epidemic in Jefferson County, Texas, in 1993 and 1994, congenital syphilis prevalence and risk factors were determined and local prenatal syphilis screening practices were assessed. METHODS: Medical records were reviewed, pregnant women with syphilis were interviewed, and prenatal care providers were surveyed. RESULTS: Of 91 women, 59 (65%) had infants with congenital syphilis. Among African Americans, the prevalence per 1000 live births was 24.1 in 1994 and 17.9 in 1995. Of the 50 women with at least 2 prenatal care visits who had infants with congenital syphilis, 15 (30%) had received inadequate testing. Only 16% of 31 providers obtained an early third-trimester syphilis test on all patients. CONCLUSIONS: Inadequate prenatal testing contributed to this outbreak of congenital syphilis.

Surface enhanced Raman spectroscopic monitor of P. acnes lipid hydrolysis in vitro.

Surface enhanced Raman spectroscopy (SERS) at a silver microelectrode was used to monitor bacterial hydrolysis of triglycerides in lipid mixtures that model sebaceous gland secretions. Mixtures of wax esters, squalene, triolein, and triisostearin were used as model skin secretions. The transformation was followed in vitro as changes in the SERS caused by hydrolysis of triglyceride to fatty acid. The fatty acid was adsorbed as its carboxylate, which is readily identified by the characteristic band at ca. 1395 cm(-1). Co-adsorption of propionate was also observed. The technique can also confirm the presence of bacteria by detection of short chain carboxylic acids released as products of fermentation during the growth of these cells.

A detailed lectin analysis of IgG glycosylation, demonstrating disease specific changes in terminal galactose and N-acetylglucosamine.

Serum IgG from rheumatoid arthritis patients contains a decreased number of oligosaccharide structures ending in galactose and thus there is an increase in N-acetylglucosamine as the terminal sugar, compared with healthy individuals. The relationship between these two sugars varies depending on the disease examined: IgG from patients with rheumatoid arthritis, juvenile onset chronic arthritis and Crohn's disease are at one extreme, and exhibit a reciprocal galactose:N-acetylglucosamine relationship, while Sjögren's syndrome and osteoarthritis IgG are at the other extreme, exhibiting a parallel increase in the expression of both galactose and N-acetylglucosamine. These results may occur as a consequence of more than one glycosylation site which is differentially glycosylated, but more likely by changes in the level of bisecting N-acetylglucosamine.

The influence of diabetes, hypertension, and stroke on ethnic differences in physical and cognitive functioning in an ethnically diverse older population.

Prevention of decline in cognitive and physical functioning in the elderly has become an important focus in geriatric medicine. Hispanics are among the fastest-growing group of elderly in the United States, yet few data are available on functional impairments in this group. We examined the association between ethnicity (non-Hispanic whites [NHW], English-speaking Hispanics [EH], and Spanish-speaking Hispanics [SH]) and cognitive status, self-assessed functional status, and physical performance in a community-dwelling sample of 589 people aged > or = 60 years. The purpose of this study was to examine the association between ethnicity and these measures of functional status and to evaluate the influence of comorbid stroke, diabetes, and hypertension on this association. We found that EH and SH had significantly lower scores on the MiniMental State Exam than NHW, but that this difference was almost entirely due to educational level. When SH whose educational attainment was grade 8 or higher were compared to NHWs, there were no differences in cognitive functioning. Those with diabetes and stroke had poorer cognitive functioning. Among those with stroke, EH and SH women had more self-assessed functional limitations (IADLs and ADLs) than NHW. Male SH and EH with diabetes also had more self-assessed functional limitations than NHW. SH with two or three of these conditions had more IADL limitations. Our results suggest that elderly community-dwelling Hispanics experience greater levels of disability and that this is due, in part, to lower socioeconomic status and higher prevalence of disabling conditions.

Remembering the earthquake: direct experience vs. hearing the news.

Three groups of informants--two in California, one in Atlanta--recalled their experiences of the 1989 Loma Prieta earthquake shortly after the event and again 11/2 years later. The Californians' recalls of their own earthquake experiences were virtually perfect. Even their recalls of hearing the news of an earthquake-related event were very good: much higher than Atlantan recalls of hearing about the quake itself. Atlantans who had relatives in the affected area remembered significantly more than those who did not. These data show that personal involvement in the quake led to greatly improved recall, but do not show why. Many Californian informants reported low levels of stress/arousal during the event; arousal ratings were not significantly correlated with recall. The authors suggest that repeated narrative rehearsals may have played an important role.

A seven-day Helicobacter pylori treatment regimen using clarithromycin, omeprazole and tripotassium dicitrato bismuthate.

AIM: To evaluate clarithromycin 500 mg t.d.s., tripotassium dicitrato bismuthate 240 mg b.d. and omeprazole 20 mg b.d. for 7 days as a Helicobacter pylori treatment regimen. METHODS: The H. pylori status of dyspeptic patients undergoing endoscopy was assessed by histology, culture and rapid urease testing of biopsies and by 13C-urea breath test. Fifty patients who were H. pylori-positive were treated with the above treatment regimen for 7 days. Those patients with active duodenal ulcers present at endoscopy were given omeprazole 20 mg nocte for a further 21 days. Not less than 28 days after completing treatment, all tests were repeated to reassess H. pylori status. Bacterial sensitivity of H. pylori cultures was determined and patients recorded any side-effects. RESULTS: On an intention-to-treat basis, H. pylori infection was cured in 90% (95% CI: 78-96%) of patients. Taste disturbance was experienced by 35% patients. Compliance was excellent, with 96% patients taking more than 95% of tablets. Metronidazole resistance was 41% but all cultures were sensitive to clarithromycin. CONCLUSIONS: This 7-day treatment achieved a high level of cure of H. pylori infection with relatively minor side-effects. It may have a role to play, particularly where there is a high level of metronidazole resistance.

Review article: quantitative leucocyte scanning in the assessment of inflammatory bowel disease activity and its response to therapy.

Inflammatory bowel disease (IBD) symptoms may be due not only to the effects of bowel inflammation, but also can result from many non-inflammatory consequences of the disease. Clinical scores and health questionnaire ratings produce a global assessment which is useful in the overall evaluation of the impact of the illness on the patient, and the effect of treatment. However many studies have failed to recognize the need to separately assess changes in the degree of bowel inflammation, in addition to a global clinical response. Radiolabelled white cell scanning using 111-indium has been shown to provide an accurate, quantitative and non-invasive method for assessing the degree of bowel inflammation in IBD and its response to therapy, using faecal collection or total body counts of radioactivity. More recently 99mTc hexamethyl propylene amine oxime (HMPAO) labelled white cell scanning has been introduced, which has advantages over the 111-indium method, including reduced radiation dosimetry and enhanced image quality. 99mTc-HMPAO scanning using three-dimensional white cell scanning (single photon emission computerized tomography; SPECT) allows visualization of the entire bowel separate from overlying structures. 99mTc-HMPAO white cell scanning with SPECT has now been computerized and automated to permit measurement of segmental and total bowel radiolabelled white cell infiltrate. This method could potentially provide the gold standard for objective assessment of the response of disease activity in Crohn's disease and ulcerative colitis, and merits application in clinical trials of novel therapies for IBD.

Age and education correction of Mini-Mental State Examination for English and Spanish-speaking elderly.

Previous research has shown that the Mini-Mental State Examination (MMS) is biased as a measure of cognitive impairment in minority and low-education patients. The purpose of this study was to (1) develop a statistical correction for effects of age and education and (2) test the efficacy of the statistically adjusted MMS (MMSAdj) as a screening test for dementia using different ethnic groups and education levels. We used a population-base community survey sample (n=590) composed of 46.6% Hispanics and 53.4% non-Hispanics to derive the statistical correction, defined as:MMSAdj = Raw MMS - (0.471 X [Education-12]) + (0.131 X [Age-70]). Ethnicity and language of test administration were not significantly related to MMSAdj in the community survey sample, but the raw MMS was strongly influenced by these factors. We used an independent sample (n=2,983) of patients evaluated through the California Alzheimer's Disease Diagnostic and Treatment Centers to test the diagnostic accuracy of the MMS and the MMSAdj across low- and high-education groups and across whites, Hispanics, and blacks. Results showed greater stability of sensitivity and specificity across education levels and ethnic groups for the MMSAdj than for the raw MMS and suggest that the MMSAdj is a preferable measure of cognitive impairment for low- education and minority individuals.

Integration of orthographic, conceptual, and episodic information on implicit and explicit tests.

An experiment was conducted to determine how orthographic and conceptual information are integrated during incidental and intentional retrieval. Subjects studied word lists with either a shallow (counting vowels) or deep (rating pleasantness) processing task, then received either an implicit or explicit word fragment completion (WFC) test. At test, word fragments contained 0, 1, 2, or 4 letters, and were accompanied by 0, 1, 2, or 3 semantically related words. On both the implicit and explicit tests, performance improved with increases in the numbers of letters and words. When semantic cues were presented with the word fragments, the implicit test became more conceptually drive. Still, conceptual processing had a larger effect in intentional than in incidental retrieval. The Fuzzy Logical Model of Perception (FLMP) provided a good description of how orthographic, semantic, and episodic information were combined during retrieval.

Comparison of 99m technetium hexamethylpropylene-amine oxime labelled leucocyte with 111-indium tropolonate labelled granulocyte scanning and ultrasound in the diagnosis of intra-abdominal abscess.

Fifty patients with suspected intra-abdominal abscess were investigated prospectively with ultrasound and with 99mTc-hexamethylpropylene-amine oxime (HMPAO) isotope labelled mixed leucocytes, using 111-In tropolonate granulocyte scanning as the reference standard. Twenty five patients had inflammatory bowel disease (three were postoperative): 21 of these had Crohn's disease and four had ulcerative colitis. The remainder comprised nine with postoperative fever and 16 with fever and abdominal pain. An abscess was diagnosed when focal activity on serial 111-In tropolonate and 99m-Tc-HMPOA images at one, three, and 24 hours resulted in activity at least equal to liver activity at 24 hours. Thirteen abscesses were diagnosed using each type of white cell scanning, resulting in 100% sensitivity for 99m-Tc-HMPAO compared with 111-In tropolonate. Bowel inflammation was easily distinguished from abscess on serial images. Eight of these 13 abscesses were detected by ultrasound. Altogether 17 abscesses were found. Ultrasound detected 12, including four liver abscesses which were not purulent and had not been detected by white cell scanning. Ultrasound had a sensitivity of 71% (12 of 17) and a specificity of 87% (33 of 38) using all confirmed abscesses as the reference standard. White cell scanning showed a sensitivity of 76% (13 of 17: as a result of the four non-purulent liver abscesses) and a specificity of 100%. 99m-Tc-HMPAO scanning is as accurate as 111-In tropolonate scanning, and has several advantages including simplicity, availability, superior image quality, and reduced radiation dose. Both methods are more sensitive and specific than ultrasound for intra-abdominal abscess detection but ultrasound is advisable if a neutrophil infiltrate is not suspected.