Adaptive resource allocation for efficient patient scheduling

Objective Efficient scheduling of patient appointments on expensive resources is a complex and dynamic task. A resource is typically used by several patient groups. To service these groups, resource capacity is often allocated per group, explicitly or implicitly. Importantly, due to fluctuations in demand, for the most efficient use of resources this allocation must be flexible. Methods We present an adaptive approach to automatic optimization of resource calendars. In our approach, the allocation of capacity to different patient groups is flexible and adaptive to the current and expected future situation. We additionally present an approach to determine optimal resource openings hours on a larger time frame. Our model and its parameter values are based on extensive case analysis at the Academic Medical Hospital Amsterdam. Results and conclusion We have implemented a comprehensive computer simulation of the application case. Simulation experiments show that our approach of adaptive capacity allocation improves the performance of scheduling patients groups with different attributes and makes efficient use of resource capacity

Sonography for hip joint effusion in adults with hip pain

OBJECTIVE: To study the prevalence of ultrasonic hip joint effusion and its relation with clinical, radiological and laboratory (ESR) findings in adults with hip pain. METHODS: Patients (n = 224) aged 50 years or older with hip pain, referred by the general practitioner for radiological investigation, underwent a standardised examination. The distance between the ventral capsule and the femoral neck, an increase in which represents joint effusion, was measured sonographically. Joint effusion was defined in three different ways: "effusion" according to Koski's definition, "major effusion", and "asymmetrical effusion" based on only individual side differences. RESULTS: "Effusion" was present in 80 (38%), "major effusion" in 20 (9%), and "asymmetrical effusion" in 47 (22%) patients. Pain in the groin or medial thigh, pain aggravated by lying on the side, decreased extension/internal rotation/abduction/flexion, painful external rotation, and pain on palpation in the groin showed a significant relation (adjusted for age and radiological osteoarthritis of the hip) with ultrasonic hip joint effusion. "Major effusion" showed a significant relation with an increased ESR. When patients with bilateral pain and increased ESR were excluded, a side difference in the range of motion of extension of the hip was shown to be a good predictor for "asymmetrical effusion" (positive predictive value: 71%, negative predictive value: 80%). CONCLUSION: This study showed a relatively high prevalence of ultrasonic joint effusion in adults with hip pain in general practice. Furthermore the results indicate a relation between joint effusion and clinical signs

Pulmonary hypertension after transjugular intrahepatic portosystemic shunt (TIPS)

We reported the case of a patient in whom severe, and ultimately fatal, pulmonary hypertension developed 1.5 yrs after transjugular intrahepatic portosystemic shunt (TIPS). Pulmonary artery pressures were not affected by 100% oxygen, prostacyclin or nifedipine. Postmortem examinations showed pulmonary and vascular abnormalities typical of pulmonary hypertension. Pulmonary artery pressures should be measured in each patient with otherwise not readily explained dyspnoea following transjugular intrahepatic portosystemic shunt

Endoanal MRI of the anal sphincter complex: correlation with cross-sectional anatomy and histology

The purpose of this study was to correlate the in vivo endoanal MRI findings of the anal sphincter with the cross-sectional anatomy and histology. Fourteen patients with rectal tumours were examined with a rigid endoanal MR coil before undergoing abdominoperineal resection. In addition, 12 cadavers were used to obtain cross-sectional anatomical sections. The images were correlated with the histology and anatomy of the resected rectal specimens as well as with the cross-sectional anatomical sections of the 12 cadavers. The findings in 8 patients, 11 rectal preparations, and 10 cadavers, could be compared. In these cases, there was an excellent correlation between endoanal MRI and the cross-sectional cadaver anatomy and histology. With endoanal MRI, all muscle layers of the anal canal wall, comprising the internal anal sphincter, longitudinal muscle, the external anal sphincter and the puborectalis muscle wer

Prospective comparative study of spiral computer tomography and magnetic resonance imaging for detection of hepatocellular carcinoma

BACKGROUND: Hepatocellular carcinoma (HCC) is often detected at a relatively late stage when tumour size prohibits curative surgery. Screening to detect HCC at an early stage is performed for patients at risk. AIM: The aim of this study was to compare prospectively the diagnostic accuracy and classification for management of the two state of the art secondline imaging techniques: triphasic spiral computer tomography (CT) and super paramagnetic iron oxide (SPIO) enhanced magnetic resonance imaging (MRI). PATIENTS: Sixty one patients were evaluated between January 1996 and January 1998. Patients underwent CT and MRI within a mean interval of 6.75 days. METHODS: CT and MRI were evaluated blindly for the presence and number of lesions, characterisation of these lesions, and classification for management. For comparison of the data on characterisation, the CT and MRI findings were compared with histopathological studies of the surgical specimens and/or follow up imaging. Data of patients not lost to follow up were available to January 2001. RESULTS: SPIO enhanced MRI detected more lesions and overall smaller lesions than triphasic spiral CT (number of lesions 189 v 124; median diameter 1.0 v 1.8 cm; Spearman rank's correlation coefficient 0.63, p<0.001). There was no significant difference in accuracy between CT and MRI for lesion characterisation. The agreement in classification for management was very good (weighted kappa 0.91, 95% CI 0.83-0.99). CONCLUSION: SPIO enhanced MRI detects more and smaller lesions, but both techniques are comparable in terms of classification for management. SPIO enhanced MRI may be preferred as there is no exposure to ionising radiation

Fecal incontinence: endoanal US versus endoanal MR imaging

textabstractPURPOSE: To assess endoanal ultrasonography (US) and endoanal magnetic resonance (MR) imaging for mapping of anal sphincter defects that have been validated at surgery in patients with fecal incontinence. MATERIALS AND METHODS: US, MR imaging, and surgical findings in 22 women with fecal incontinence who underwent sphincter repair were retrospectively reviewed. US and MR imaging had been performed before surgery. The findings were evaluated separately and validated with surgical results. RESULTS: Endoanal MR imaging findings showed better agreement with surgical results than did endoanal US findings for diagnosis of lesions of the external sphincter (kappa value, 0.85 vs 0.53) and of the internal sphincter (kappa value, 0.64 vs 0.49). Endoanal US could not accurately demonstrate thinning of the external sphincter. MR imaging results correlated moderately with US results (kappa = 0.39). If endoanal MR images alone had been considered, the correct surgical decision would have been made in 21 (95%) patients; if endoanal US images alone had been considered, the correct decision would have been made in 17 (77%) patients. CONCLUSION: MR imaging is more accurate than US for demonstration of sphincter lesions. MR imaging provides higher spatial resolution and better inherent image contrast for lesion characterization. Endoanal MR imaging allows more precise description of the extent and structure of complex lesions and is superior for help in decisions about optimal therapy