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Philip J Robinson

Publications and source records attributed to Philip J Robinson.

14 recordsLinked to original sources
PubMed2006

Is significant cystic fibrosis-related liver disease a risk factor in the development of bone mineralization abnormalities?

In order to assess the effects of significant cystic fibrosis-related liver disease (CFLD) on bone health, we compared the bone mineral status of older children and adolescents with CFLD to those with cystic fibrosis (CF) alone. Thirteen children (age range, 10-19 years) from our clinical CF services were identified with significant CFLD (9 of these 13 patients had clinical and radiological evidence of portal hypertension). This cohort was then matched by age, gender, and anthropometric measurements with equal numbers of patients with CF alone. All patients had a dual-energy X-ray absorptiometry (DEXA) scan to determine bone mineral content (BMC), bone area (BA), bone mineral density (BMD), and bone mineral apparent density (BMAD) in the region of the lumbar spine. Blood was drawn to determine serum vitamin A, D, E, and K status and liver function tests. The best forced expired volume in 1 sec (FEV1) for each patient in the 12 months around the time of the scan was also documented. Patients with CFLD had slightly worse FEV1 (82 +/- 20% vs. 91 +/- 16%, P = 0.05) and significantly higher alanine aminotransferase (65.5 +/- 35 IU/l vs. 30 +/- 20 IU/l, P = 0.01) than those with CF alone. The mean lumbar spine BA, BMC, BMD, and BMAD were not different between children with CFLD and CF. In conclusion, the presence of significant liver disease in children with CF does not appear to be an additional risk factor for the development of abnormal bone mineralization.

Absorptiometry, Photon↗
PubMed2006

Clinical scoring systems in cystic fibrosis.

The first cystic fibrosis (CF) scoring system was published in 1958. Since then, many other scoring systems were developed. Clinical parameters, details about statistical evaluations, and recent strategic uses of scores were identified. Several similar scores aiming to assess chronic illness severity (Shwachman-Kulczycki score and a modification, Cooperman, Berneze-score and the NIH score) have not been evaluated and are out of date, given the changing natural history of CF. Of the current scoring systems, the modified Shwachman score by Doershuk is perhaps most reliable for describing follow-up studies. Scores designed for acute changes and short-term evaluation were also developed. The modified Huang score may be useful in the prognostic evaluation of patients with end-stage disease. It could also be used for discrimination of adult patients with differing disease severity and for longitudinal evaluation. Scores assessing pulmonary exacerbations could help provide consensus among clinicians regarding the need for intervention. Most of these scores require further evaluation. Although scores could provide an objective measure of disease severity, progression, need for and response to interventions, including value in selecting patients for lung transplantation and as an outcome measure for research studies, no scoring system can fulfill all these objectives. Nevertheless, there is a need for the development of a modern day longitudinal score that is sensitive, valid and reproducible, to reflect the milder disease status of patients.

Child↗
PubMed2005

Liver metastases in candidates for hepatic resection: comparison of helical CT and gadolinium- and SPIO-enhanced MR imaging.

PURPOSE: To prospectively compare accuracy of dynamic contrast material-enhanced thin-section multi-detector row helical computed tomography (CT), high-spatial-resolution three-dimensional (3D) dynamic gadolinium-enhanced magnetic resonance (MR) imaging, and superparamagnetic iron oxide (SPIO)-enhanced MR imaging with optimized gradient-echo (GRE) sequence for depiction of hepatic lesions; surgery and histologic analysis were the reference standard. MATERIALS AND METHODS: Local ethics committee approval was granted, and written informed consent was obtained. Fifty-eight patients (45 men, 13 women; age range, 47-82 years) with hepatic metastases were imaged with multi-detector row CT (3.2-mm section thickness), 3D dynamic gadolinium-enhanced MR imaging (2.5-mm effective section thickness), and SPIO-enhanced MR by using an optimized T2-weighted GRE sequence. Images were reviewed independently by two blinded observers who identified and localized lesions with a four-point confidence scale. Accuracy of each technique was measured with alternative free-response receiver operating characteristic analysis. Results were correlated with findings at surgery with intraoperative ultrasonography or histopathologic examination. Statistical differences among techniques for each observer were measured. RESULTS: Accuracy values for each observer for all metastases (n = 215) and 1.0-cm or smaller metastases (n = 80), respectively, follow: For CT, those for reader 1 were 0.82 and 0.65; for reader 2, 0.81 and 0.68. For gadolinium-enhanced MR imaging, those for reader 1 were 0.92 and 0.79; for reader 2, 0.90 and 0.76. For SPIO-enhanced MR imaging, those for reader 1 were 0.92 and 0.83; for reader 2, 0.92 and 0.81. For all metastases for both observers, there was no significant difference between MR techniques, but both were significantly more accurate than CT (P < .01). For metastases 1.0 cm or smaller and one observer, there was no significant difference between MR techniques, but both were more accurate than CT (P < .01); for the other observer, SPIO-enhanced MR imaging was more accurate than gadolinium-enhanced MR imaging (P < .05) and CT (P < .02), but there was no significant difference between gadolinium-enhanced MR imaging and CT (P = .2). CONCLUSION: Accuracy for gadolinium-enhanced MR imaging and SPIO-enhanced MR imaging was similar. Both techniques were significantly more accurate than CT.

Aged↗
PubMed2005

Effects of segregation on an epidemic Pseudomonas aeruginosa strain in a cystic fibrosis clinic.

The detection of a clonal Pseudomonas aeruginosa strain in 21% of children attending a cystic fibrosis clinic during 1999, which may have led to a worse prognosis, prompted strict infection control measures, including cohort segregation. We determined whether these strategies interrupted cross-infection within the clinic. Patients from 1999 were observed and a cross-sectional study of the 2002 clinic was performed. By 2002, the epidemic strain prevalence had decreased from 21 to 14% (p = 0.03), whereas the proportion of patients with nonepidemic P. aeruginosa strains was unchanged. The age- and sex-adjusted relative risk for epidemic strains among sputum producers in 2002 compared with 1999 was 0.64 (95% confidence interval, 0.47, 0.87; p = 0.004). Increased mortality or transfer to another clinic did not explain this reduction. Although children with epidemic strains may have had increased mortality (adjusted odds ratio, 2.0; 95% confidence interval, 0.6-6.8), they did not demonstrate greater morbidity than those with other P. aeruginosa isolates. Successful infection control measures provided additional indirect evidence for person-to-person transmission of an epidemic strain within the clinic. Further studies are needed to resolve whether cohort segregation completely eliminates cross-infection and if acquisition of epidemic isolates is associated with worse outcomes.

Adolescent↗
PubMed2004

Bile duct strictures after hepatobiliary surgery: assessment with MR cholangiography.

PURPOSE: To establish the accuracy of magnetic resonance (MR) cholangiography for diagnosis of postsurgical bile duct strictures. MATERIALS AND METHODS: Sixty-seven patients suspected of having bile duct strictures after liver transplantation (n = 54), cholecystectomy (n = 8), hepatic resection (n = 4), or pancreaticoduodenectomy (n = 1) underwent MR cholangiography. Thick-slab single-shot fast spin-echo (repetition time msec/echo time msec, 4,500/940) imaging was performed in the coronal through sagittal planes with rotation in 10 degrees increments, and contiguous thin-section images were obtained in the transverse and the optimal coronal oblique planes by using half-Fourier rapid acquisition with relaxation enhancement (1,900/96). Three blinded observers independently reviewed the MR images and recorded diagnostic features including presence of biliary stricture by using a five-point confidence scale. Receiver operating characteristic analysis was used to measure the accuracy of MR cholangiography. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated. Final diagnosis was established at surgery (n = 29) and direct cholangiography (23 of 29) or at direct cholangiography, liver biopsy, and/or serial liver function tests (n = 38). RESULTS: Thirty-three of 67 patients had strictures confirmed with the reference standard. MR cholangiography enabled correct diagnosis and depicted the site of strictures in all cases. Findings of stricture at MR cholangiography were false-positive in five patients with moderate duct dilatation and caliber change at the level of the anastomosis. Mean accuracy, sensitivity, specificity, PPV, and NPV were 94%, 97%, 74%, 86%, and 96%, respectively. CONCLUSION: MR cholangiography is as sensitive as direct cholangiography for the assessment of bile duct strictures after hepatobiliary surgery but may lead to overestimation of the importance of duct dilatation and caliber change.

Adult↗
PubMed2004

Improved detection of focal liver lesions at MR imaging: multicenter comparison of gadoxetic acid-enhanced MR images with intraoperative findings.

PURPOSE: To evaluate the safety and efficacy of gadoxetic acid disodium-enhanced magnetic resonance (MR) imaging for the detection of focal liver lesions, with results of histopathologic examination and/or intraoperative ultrasonography used as a standard of reference. MATERIALS AND METHODS: One hundred sixty-nine patients who were known to have or suspected of having focal liver lesions and were scheduled for liver surgery were included in this study. Results in 131 patients could be included in the efficacy analysis. MR imaging was performed before and immediately and 20 minutes after bolus injection of 0.025 mmol/kg of the liver-specific hepatobiliary contrast agent gadoxetic acid. T1-weighted gradient-echo (with and without fat saturation and including dynamic data sets) and T2-weighted fast spin-echo/turbo spin-echo sequences were performed. All images were evaluated on site and by three independent and blinded off-site reviewers. Lesion matching based on the standard-of-reference results was performed. Differences in lesion detection with precontrast and with postcontrast MR images were assessed with the two-sided Wilcoxon signed rank test. RESULTS: Gadoxetic acid was well tolerated. In the on-site review, the number of patients in whom all lesions were correctly matched increased from 89 of 129 patients at precontrast MR imaging to 103 of 129 patients at postcontrast MR imaging. In the off-site evaluation, the number of patients in whom all lesions were correctly matched and the corresponding sensitivity values increased from 72 (55.8%), 68 (52.7%), and 66 (51.2%) with the precontrast images to 88 (68.2%), 69 (53.5%), and 76 (58.9%) with the postcontrast images for readers 1, 2, and 3, respectively. Two of the three blinded readers showed a statistically significant difference in lesion detection between precontrast and postcontrast MR imaging (P <.001 and P =.008). A large number of additionally correctly detected and localized lesions were smaller than 1 cm. CONCLUSION: MR imaging with gadoxetic acid is safe and improves lesion detection and localization.

Adult↗
PubMed2003

Colorectal hepatic metastases: detection with SPIO-enhanced breath-hold MR imaging--comparison of optimized sequences.

PURPOSE: To compare the accuracy of four breath-hold magnetic resonance (MR) imaging sequences to establish the most effective superparamagnetic iron oxide (SPIO)-enhanced sequence for detection of colorectal hepatic metastases. MATERIALS AND METHODS: Thirty-one patients with colorectal hepatic metastases underwent T1-weighted gradient-echo (GRE) and T2-weighted fast spin-echo (FSE) MR imaging before and after SPIO enhancement. Four sequences were optimized for lesion detection: T2-weighted FSE, multiecho data image combination (MEDIC), T2-weighted GRE with an 11-msec echo time (TE), and T2-weighted GRE with a 15-msec TE. Images were reviewed independently by three blinded observers. The accuracy of each sequence was measured by using alternative free-response receiver operating characteristic analysis. All results were correlated with findings at surgery, intraoperative ultrasonography, or histopathologic examination. Differences between the mean results of the three observers were measured by using the Student t test. RESULTS: Postcontrast T2-weighted GRE sequences were the most accurate and were significantly superior to postcontrast T2-weighted FSE and unenhanced sequences alone (P <.05). For all lesions that were malignant or smaller than 1 cm, respectively, mean accuracies of postcontrast sequences were 0.082 and 0.64 for T2-weighted FSE, 0.90 and 0.78 for MEDIC, 0.92 and 0.80 for GRE with an 11-msec TE, 0.93 and 0.82 for GRE with a 15-msec TE, and 0.81 and 0.62 for unenhanced sequences. CONCLUSION: Optimized SPIO-enhanced T2-weighted GRE combined with unenhanced T2-weighted FSE MR sequences were the most sensitive. Breath-hold FSE postcontrast sequences offer no improvement in sensitivity compared with unenhanced sequences alone.

Colorectal Neoplasms↗
PubMed2003

Airway alveolar attachment points and exposure to cigarette smoke in utero.

The harmful effects of in utero cigarette smoke exposure include increased asthma symptoms and reduced lung function during the neonatal period, increased airway responsiveness to inhaled stimuli, and an increased risk of sudden infant death syndrome. Altered lung function may result from altered airway/lung structure. Airway dimensions, alveolar attachment points, and parenchymal elastin content were measured in 32 infants who died from sudden infant death syndrome and were grouped according to their perinatal cigarette smoke exposure. Compared with those without any exposure to cigarette smoke, the distance between alveolar attachments on airways was greater (p < 0.001) in infants exposed to cigarette smoke only in utero or both in utero and during the postnatal period but not different in those with only postnatal exposure. The percentage of elastin within the alveolar walls was similar in all the exposure groups. These findings suggest that in utero cigarette smoke exposure may result in abnormal airway function due to a reduction of the forces opposing airway narrowing.

Bronchi↗
PubMed2003

Superparamagnetic iron oxide (SPIO) enhancement in the cirrhotic liver: a comparison of two doses of ferumoxides in patients with advanced disease.

The aim of this study was to establish whether enhancement of the liver by the MRI contrast agent ferumoxides could be effectively achieved at a reduced dose of 7.5 micromol/kg in patients with advanced liver cirrhosis. Forty-two liver transplant candidates with end-stage cirrhosis underwent SPIO-enhanced MRI at 1.5T, using either 15 micromol/kg or 7.5 micromol/kg ferumoxides. The lower dose of ferumoxides was also used in 21 non-cirrhotic patients with colorectal liver metastases who acted as a control group. The percentage signal intensity loss (PSIL) after SPIO was measured in all patients, and in those patients with tumors the post-SPIO contrast-to-noise ratio (CNR) was measured. The median PSIL after SPIO in the high dose cirrhotic (HDLC), low dose non-cirrhotic (LDNC) and low dose cirrhotic (LDLC) patients was 86.3%, 74.6%, and 64.2% respectively. These differences were significant using the Mann-Whitney U test. Tumors were found in 8 patients in the high dose cirrhotic group, 9 in the low dose cirrhotic group, and all 21 of the control group. No significant differences were found between the CNR values after SPIO in the 3 groups (median values HDLC 15.1, LDNC 23.7, LDLC 19.5). In patients with late-stage cirrhosis the PSIL after SPIO was significantly less at 7.5 micromol/kg than at 15 micromol/kg, but both doses produced a substantial loss of signal. Lesion to liver CNR was not adversely affected by using the lower dose, so when imaging at 1.5T the authors would recommend using 7.5 micromol/kg in patients with liver cirrhosis.

Adult↗
PubMed2003

Major haemoptysis in children with cystic fibrosis: a 20-year retrospective study.

BACKGROUND: Major haemoptysis occurs in approximately 1% of children with cystic fibrosis (CF). This report describes management and follow-up of these children at a tertiary centre in Australia. METHODS: Retrospective review of medical records from 1980-1999. RESULTS: Fifty-one children (45% female) had major haemoptysis (102 episodes). Mean age at first episode was 15 years (range 7-19) and mean FEV(1) was 56% predicted (range 14-98). Massive life-threatening haemoptysis was not confined to those with severe lung disease (FEV1 < 50% predicted). Bronchial artery embolisation (BAE) was more likely to be the initial treatment for those with massive haemoptysis and chronic recurrent bleeding tended to be treated conservatively (P = 0.01). Overall, 52 BAE were performed in 28 children with an immediate success rate of 98%; 13 children (46%) had repeated BAE. Four patients died as a direct result of severe haemoptysis. Mean follow-up was 54 months (range 0.5-183). Median survival time (Kaplan-Meier estimate) after first haemoptysis was 70 months, with a significantly longer survival for male patients independent of age (RR 3.8; 95% CI 1.7-8.8; P = 0.001). Median survival time following initial treatment with BAE was longer (103 months) compared to conservative treatment (52 months, P = 0.09). CONCLUSIONS: Massive haemoptysis was unrelated to the severity of lung disease and was more likely to be treated with embolisation. BAE was highly effective, however, 46% of the children required re-embolisation at some time, which is similar to the recurrence risk for major hemoptysis treated conservatively on longer term follow-up.

Adolescent↗
PubMed2003

Hepatocellular carcinoma in cirrhotic livers: double-contrast thin-section MR imaging with pathologic correlation of explanted tissue.

OBJECTIVE: The aim of our study was to determine the sensitivity of double-contrast MR imaging in the detection of hepatocellular carcinomas in patients with a cirrhotic liver. SUBJECTS AND METHODS: Thirty-one patients underwent double-contrast MR imaging and subsequent liver transplantation. Breath-hold T1- and T2-weighted MR images were obtained before and after administration of superparamagnetic iron oxide, and three-dimensional T1-weighted gradient-recalled echo MR images were obtained 10, 40, and 120 sec after a bolus injection of gadolinium. Hypervascular lesions that failed to take up superparamagnetic iron oxide were regarded as showing typical characteristics of hepatocellular carcinoma; lesions that had only one of these two characteristics (either hypervascularity or failure to take up superparamagnetic iron oxide) were regarded as highly suspicious for hepatocellular carcinoma. Radiology reports were correlated with pathology reports for the explanted livers. RESULTS: Thirty-two hepatocellular carcinomas were found in 14 of the 31 patients. Combining the number of MR imaging reports citing lesions that were "typical of hepatocellular carcinoma" with the number of those citing lesions that were "highly suspicious," we found that for 25 of 32 lesions, an accurate MR imaging diagnosis of hepatocellular carcinoma was made (overall sensitivity, 78%). These lesions included 10 of the 11 lesions that were larger than 20 mm (sensitivity, 91%), 12 of the 13 lesions that were 11-20 mm (sensitivity, 92%), and three of the eight lesions that were 10 mm or less (sensitivity, 38%). Nineteen (76%) of 25 lesions had characteristics considered typical of hepatocellular carcinoma; the remaining six lesions either failed to take up superparamagnetic iron oxide and were hypovascular or were hypervascular but showed some uptake of superparamagnetic iron oxide. CONCLUSION: In patients with a cirrhotic liver, double-contrast MR imaging is highly sensitive in the diagnosis of hepatocellular carcinomas of 10 mm or larger, but success in the identification of tumors smaller than 10 mm is still limited.

Adult↗
PubMed2002

How to detect hepatocellular carcinoma in cirrhosis.

Cirrhosis predisposes to hepatocellular carcinoma (HCC) which develops by sequential steps of de-differentiation of hepatocytes from regenerative nodules via borderline (dysplastic) nodules to frankly malignant HCC. Effective treatment depends on early recognition of HCC, so the key tasks for imaging are firstly recognising the presence of a suspicious lesion, and secondly differentiating between benign, borderline and malignant nodules. Screening of high-risk cirrhotic patients with sonography and measurement of alpha fetoprotein (AFP) is helpful but will not reliably differentiate small HCC from benign or dysplastic nodules. Large HCCs can usually be recognised by their characteristic morphology on imaging, but the appearances of smaller benign and malignant nodules show considerable overlap on unenhanced sonography, CT and MRI. Increasing degrees of histological malignancy are associated with increasing arterialisation and loss of portal blood supply, so the recognition of HCC requires the use of dynamic imaging with contrast-enhanced CT or T1-weighted MRI with gadolinium enhancement. Sonography with microbubble contrast media now offers another method for detecting arterialised nodules; however, some non-malignant nodules show arterial hypervascularity and a minority of HCCs are hypovascular, so the assessment of perfusion does not conclusively distinguish benign from malignant lesions. Kupffer cell function is another attribute of liver tissue which can be explored using MRI with superparamagnetic iron oxide particles (SPIO). Experience thus far suggests that uptake of SPIO is an effective discriminator between benign and malignant nodules. The combination of SPIO with gadolinium-enhanced MRI offers the opportunity for imaging characterisation of cirrhotic nodules by cellular function as well as by blood supply, and this approach is now proposed as the examination of choice for detecting HCC in cirrhosis.

Carcinoma, Hepatocellular↗
PubMed2002

Dornase alfa in early cystic fibrosis lung disease.

Leukocytes that infiltrate cystic fibrosis (CF) sputum as a result of infection have long been known to liberate large amounts of DNA, which increases sputum viscosity and promotes the cycle of chronic lung infection and inflammation that ultimately leads to respiratory failure and death. It was only recently recognized that this vicious cycle begins in infancy, and that architectural damage to CF lungs is detectable even in children with normal pulmonary function tests. Dornase alfa cleaves DNA and improves sputum viscosity in CF. Although its efficacy in reducing the risk of acute infectious exacerbations and improving pulmonary function has been recognized for a decade, there is growing interest in its potential for long-term benefit in young patients with mild lung function abnormalities. The Pulmozyme Early Intervention Trial (PEIT) study demonstrated that dornase alfa reduces the risk of pulmonary exacerbations requiring i.v. antibiotic treatment by 34% and improves forced expiratory flow at 25-75% of forced vital capacity (FEF(25-75)), mid-expiratory flow at 50% of forced vital capacity (MEF), and forced expired volume in 1 sec (FEV(1)) over a 2-year period in CF patients with almost normal lung function. A post hoc subgroup analysis suggests that the magnitude of pulmonary function test (PFT) changes may vary, depending on the initial degree of lung function impairment, but that the reduction in exacerbations appears to be a consistent benefit. These results support the current view that CF patients benefit from intervention early in the course of their lung disease.

Cystic Fibrosis↗