Can radiological assessment of abdominal computerized scans diagnose encapsulating peritoneal sclerosis in long-term peritoneal dialysis patients?

AIM: Encapsulating peritoneal sclerosis (EPS) is a rare but potentially devastating complication of long-term peritoneal dialysis (PD). Changes to the peritoneal membrane occur with duration of PD therapy. To determine the potential effect of prospective computerized tomography (CT) scanning, we reviewed the scans of patients who had developed EPS compared with those without EPS. METHODS: We retrospectively compared CT scans that had been prospectively performed in a screening program for PD patients after 4 years of PD and compared scans from 18 patients with confirmed EPS and 26 vintage matched controls without EPS. Anonymized scans were reported independently by two blinded experienced radiologists. RESULTS: Peritoneal thickening, calcification, bowel tethering, thickening and dilatation were significantly more commonly reported in the EPS group. Total combined radiological scores, also including septation within peritoneal fluid, were significantly higher in the EPS group and the greatest for those who died as a consequence of EPS. Simplified scoring based on presence or absence, then for a score of ≥3.0, gave a receiver operating characteristic value of 0.87 for EPS, with a sensitivity of 78% and specificity of 85%, respectively. Inter-observer agreement varied from poor to good, being the greatest for calcification and bowel dilatation and the lowest for peritoneal thickening. CONCLUSION: CT scan reporting can differentiate EPS from peritoneal changes associated with duration of PD therapy. Severity of abnormalities was associated with clinical outcomes. However, inter-observer agreement varies with different radiological appearances, and future studies are required to determine weighting of radiological changes to provide prognostic information for clinicians and patients.

Incidence of facial clefts in Cambridge, United Kingdom.

The aim of this study was to determine the incidence of facial clefting in Cambridge, UK, using multiple resources of ascertainment and to relate the findings to antenatal ultrasound screening (AUS) detection rates. AUS records from an obstetric ultrasound department, post-natal records from the regional craniofacial unit, and autopsy reports of foetuses over 16 weeks' gestational age from a regional pathology department from 1993 to 1997 were retrospectively reviewed. Cross-referencing between the three data sets identified all cases of facial clefts. Of 23,577 live and stillbirths, 30 had facial clefts. AUS detected 17 of these. Sixteen of the 30 had isolated facial clefts. Others had associated anomalies, chromosomal defects, or syndromes. Percentages and confidence intervals were calculated from the above data. Twenty-one resulted in live births, seven terminations, and two foetal deaths. Overall, detection rate by AUS was 65 percent [67 percent isolated cleft lip, 93 per cent cleft lip and palate (CLP), and 22 percent isolated cleft palate], with no false positives. The incidence of facial clefts was 0.127 percent (95 percent confidence interval 0.089-0.182 percent); the incidence for isolated CLP was lower than previously reported: 0.067 percent (0.042-0.110 percent). With one exception, all terminations were in foetuses with multiple anomalies. The figures presented will enable joint CLP clinics to give parents information of termination rates. The study allows pre-pregnancy counselling of families previously affected by clefting about the reliability of AUS detection rates.

The Blood Neutrophil Count After 1 Month of Treatment Predicts the Radiologic Severity of Lung Disease at Treatment End.

BACKGROUND: Lung disease after tuberculous confers significant morbidity. However, the determinants of persistent lung damage in TB are not well established. We investigated associations between TB-associated radiologic changes and sociodemographic factors, surrogates of bacillary burden, and blood inflammatory markers at initiation of therapy and after 1 month. RESEARCH QUESTION: What are the predictors of radiologic severity at the end of TB treatment for TB? STUDY DESIGN AND METHODS: We collected data from patients treated for drug-sensitive pulmonary TB at our center over a 5.5-year period. We recorded age, sex, ethnicity, smoking status, symptom duration, sputum smear grade, time to culture positivity, and blood results (C-reactive protein and neutrophil count) at baseline and after 1 month of treatment. Chest radiographs obtained at baseline, 2 months, and end of treatment were assessed independently by two radiologists and scored using a validated system. Relationships between predictor variables and radiologic outcomes were assessed using linear or binary logistic regression. RESULTS: We assessed 154 individuals with a mean age of 37 years, 63% of whom were men. In a multivariate analysis, baseline radiologic severity correlated with sputum smear grade (P = 0.003) and neutrophil count (P < 0.001). At end of treatment, only the 1-month neutrophil count was associated significantly with overall radiologic severity in the multivariate analysis (r = 0.34; P = 0.003) and remained significant after controlling for baseline radiologic scores. The 1-month neutrophil count also was the only independent correlate of volume loss and pleural thickening at the end of treatment and was significantly higher in patients with persistent cavitation or effusion vs those without. INTERPRETATION: Persistent neutrophilic inflammation after 1 month of TB therapy is associated with poor radiologic outcome, suggesting a target for interventions to minimize lung disease after tuberculous.

Complications of continuous ambulatory peritoneal dialysis.

Continuous ambulatory peritoneal dialysis (CAPD) is used to treat end-stage renal failure in an increasing number of patients. CAPD has an advantage over hemodialysis in that it allows patients greater freedom to perform daily activities; it also provides other clinical benefits. However, the long-term effectiveness of CAPD is limited by complications, which have various causes. Complications with an infectious cause include bacterial peritonitis, tuberculous peritonitis, and infections of the catheter exit site and tunnel. Noninfectious complications include catheter dysfunction, dialysate leakage, hernias, and sclerosing encapsulating peritonitis. Many imaging modalities-radiography, ultrasonography, peritoneal scintigraphy, computed tomography (CT), and magnetic resonance (MR) imaging-are useful for characterizing these complications. CT peritoneography and MR peritoneography are techniques specifically suited to this purpose. Imaging plays a critical role in ensuring that complications are detected early and managed appropriately.

High definition three-dimensional ultrasound to localise the tumour bed: a breast radiotherapy planning study.

BACKGROUND AND PURPOSE: Complex radiation techniques, such as conformal radiotherapy for partial breast irradiation, require accurate localisation of the tumour bed. This study investigated high definition 3D ultrasound for breast tumour bed localisation. Study aims were: firstly, to determine how easily a tumour cavity could be visualised with 3D ultrasound; secondly, to determine the accuracy of computed tomography (CT) and 3D ultrasound co-registration; thirdly, to compare 3D ultrasound with other methods of localisation. MATERIALS AND METHODS: 3D ultrasound examinations were carried out in 40 women attending for breast radiotherapy. 3D position data were co-registered with the radiotherapy planning CT. 2D ultrasound and CT, surgical clips and CT, and CT alone were also used to localise the tumour bed in 32/40, 14/40 and 5/40 patients, respectively. Tumour bed volume and centre of gravity measurements for all methods of localisation were compared. RESULTS: Mean surgery to imaging interval was 44 days (range 23-86 days). The post-operative cavity was seen in all cases using the 3D ultrasound, and was graded as highly visible, visible and subtle in 21/40 (53%), 12/40 (30%) and 7/40 (17%) cases, respectively. There was a statistically significant improvement in the ability of 3D ultrasound to localise the tumour bed compared with 2D ultrasound. CT-ultrasound registration was achieved in all cases. Two-dimensional and 3D ultrasound showed smaller tumour bed volumes than clips. CONCLUSIONS: Three-dimensional ultrasound localisation of the tumour bed appears superior to 2D ultrasound. It can also be co-registered with a planning CT, thus allowing additional information on the size and location of the tumour bed to be integrated into complex radiotherapy planning.

Rapid registration for wide field of view freehand three-dimensional ultrasound.

A freehand scanning protocol is the only way to acquire arbitrary large volumes of three-dimensional ultrasound (US) data. For some applications, multiple freehand sweeps are required to cover the area of interest. Aligning these multiple sweeps is difficult, typically requiring nonrigid image-based registration as well as the readings from the spatial locator attached to the US probe. Conventionally, nonrigid warps are achieved through general elastic spline deformations, which are expensive to compute and difficult to constrain. This paper presents an alternative registration technique, where the warp's degrees of freedom are carefully linked to the mechanics of the freehand scanning process. The technique is assessed through an extensive series of in vivo experiments, which reveal a registration precision of a few pixels with comparatively little computational load.

Sensorless freehand 3-D ultrasound using regression of the echo intensity.

In freehand 3-D ultrasound (US), a position sensor is attached to the probe of a 2-D US machine. The resulting 3-D data permit flexible visualisation and more accurate volume measurement than can be achieved using 2-D B-scans alone; however, the use of the position sensor can be inconvenient for the clinician. The objective is, thus, to replace the sensor with a technique for estimating the probe trajectory based on the B-scan images, themselves. One such technique exists, based on decorrelation algorithms. This paper presents an alternative approach based on linear regression of the echo-envelope intensity signal. A probabilistic analysis of the speckle characteristics of the US signal leads to a linear model, on which the regression algorithm is based. The gradient parameter of this model is shown to be directly related to probe motion. The viability of the new approach is demonstrated through simulations and in vitro and in vivo experiments.

High-definition freehand 3-D ultrasound.

This paper describes a high-definition freehand 3-D ultrasound (US) system, with accuracy surpassing that of previously documented systems. 3-D point location accuracy within a US data set can be achieved to within 0.5 mm. Such accuracy is possible through a series of novel system-design and calibration techniques. The accuracy is quantified using a purpose-built tissue-mimicking phantom, designed to create realistic clinical conditions without compromising the accuracy of the measurement procedure. The paper includes a thorough discussion of the various ways of measuring system accuracy and their relative merits; and compares, in this context, all recently documented freehand 3-D US systems.

Abdominal wall hernias: a cross-sectional pictorial review.

The classification of abdominal wall hernias is often made difficult by confusing eponymous and anatomic nomenclature. In this article, we review the anatomy that defines the various types of hernias. The specific cross-sectional radiologic features required to correctly identify each type are then emphasized. The appropriate clinical context and the merits of the various imaging techniques available for the investigation of abdominal wall hernias are also discussed.

Genital uptake in renal transplant scintigraphy: is it normal blood pooling?

Although visualization of the genitalia on Tc-99m DTPA transplant renography has been reported previously, its frequency and clinical significance have not been fully evaluated. The authors conducted a retrospective evaluation of 153 renal transplant scintigrams obtained in 129 patients during a 2-year period. The results showed that significant genital blood pooling occurred in nearly 50% of studies. Because the finding was commonly associated with little or no radioactive urine in the bladder, as in acute tubular necrosis or poor graft function, exaggeration of the normal blood pool was thought to be the possible cause for its occurrence. It is, however, important to distinguish genital blood-pool activity from the bladder with radioactive urine to avoid making an incorrect diagnosis.