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PubMed1998

Potential acuity meter versus scanning laser ophthalmoscope to predict visual acuity in cataract patients.

PURPOSE: To compare the relative abilities of the Potential Acuity Meter (PAM) and the Scanning Laser Ophthalmoscope (SLO) to predict the postoperative visual acuity in patients with mild to dense cataract. SETTING: Gimbel Eye Centre, Calgary, Alberta, Canada. METHODS: In this single-masked prospective study of 31 consecutive eyes with mild to dense cataract and a best corrected visual acuity (BCVA) of 20/40 or less, patients had predictive visual acuity (PVA) testing using the PAM and SLO. Preoperative and postoperative BCVA was recorded using Snellen charts. Differences between PVA and postoperative BCVA results were assessed by a two-tailed t-test and correlation analysis. RESULTS: The SLO was correct within two lines of outcome in 30 of 31 eyes and the PAM, in 19 of 31 eyes. A two-tailed dependent t-test showed a significant difference between predicted and final visual acuity for the PAM (P = .0001) and a nonsignificant difference for the predicted and final visual acuity for the SLO. A correlation analysis showed a mild correlation for the PAM (r = .49) and a good correlation for the SLO (r = .81). For a prediction of better or worse than 20/40, the SLO showed a sensitivity of 0.964 and specificity of 1.0 and the PAM, of 0.67 and 1.0, respectively. CONCLUSION: The SLO was more accurate than the PAM in predicting visual acuity after cataract surgery. The relative cost of the SLO is potentially restrictive to its widespread clinical application. However, the cost/benefit in terms of patient satisfaction with predictable surgical results should be considered.

Aged↗
PubMed1998

Quality of life in elderly patients with COPD: measurement and predictive factors.

Chronic obstructive pulmonary disease (COPD) is a major cause of morbidity in old age. It leads to reduced quality of life (QoL), but the factors that contribute to this are less understood. There is no consensus on measurement of QoL in elderly COPD patients. We assessed (a) factors predicting QoL in elderly COPD out-patients and (b) specificity (SP), sensitivity (SEN), positive and negative predictive values (PPV and NPV) and repeatability of two disease-specific QoL instruments, the Chronic Respiratory Disease Questionnaire (CRQ) and the Breathing Problems Questionnaire (BPQ) in elderly people. All subjects also completed an ADL measure [Nottingham Extended ADL (NEADL)] and a measure of psychological well-being [Brief Assessment of Depression Cards (BASDEC)] as well as a 6-min walk test. Subjects comprised 96 (56 men) elderly out-patients with irreversible COPD aged 70-93 years (mean 78) who were clinically stable for > or = 6 weeks. Controls were 55 (23 men) aged 71-90 years (mean 78) with normal lung function. All were cognitively intact. Mean FEV1/FVC in COPD subjects was 45.5 (SE = 1.4)% and for controls was 71.4 (SE = 1.3)%. Repeatability was good for both BPQ and CRQ with no significant difference. There were no significant differences in specificity and positive predictive values between the two questionnaires but BPQ performed better than CRQ with regard to sensitivity (P = 0.02) and NPV (P < 0.001). A multiple regression analysis was used to identify variables that best predicted BPQ and CRQ in COPD subjects. For BPQ predictive values were NEADL (P < 0.0001); BASDEC (P < 0.0001); age (P < 0.0001); 6-min walk distance (P = 0.001); body mass index (P < 0.05); resting oxygen saturation (P < 0.05); and household composition (living alone or with relatives, P = 0.05). In contrast only the following predicted CRQ: NEADL, BASDEC and resting oxygen saturation. Sixteen per cent of the variance in BPQ was accounted for by NEADL score, 9% by BASDEC, 4% by age and 3% by 6-min walk distance (total r2 = 0.70). It was concluded that: (1) BPQ provides more valid assessment than CRQ of QoL in elderly COPD subjects; (2) severity of disease in terms of its impact on QoL is not predicted by lung function tests; (3) the most important determinants of QoL are ADL score and emotional status.

Activities of Daily Living↗
PubMed1997

Is the Parsonnet's score a good predictive score of mortality in adult cardiac surgery: assessment by a French multicentre study.

OBJECTIVE: Parsonnet proposed a preoperative score ("initial Parsonnet's score", which predicts the hospital mortality of adult cardiac surgery. This score was then modified by including several risk factors used in the 'SUMMIT' system ("modified Parsonnet's score", 44 variables). We wanted to assess the predictive value of these two scores in a French surgical population. METHODS: From December 1992 to April 1993, in France, we organised a prospective multicentre study on adult cardiac surgery mortality and morbidity. Data on 6649 patients were included. We analysed statistically the predictive value of each risk factor and of the two scores on mortality and morbidity at one month. RESULTS: Only 6 of the 15 variables of the initial Parsonnet's score and 19 of the 44 variables of the modified Parsonnet's score significantly influence hospital mortality. Both scores are able to predict hospital mortality and severe morbidity, but the modified Parsonnet's score has the best predictive value (initial Parsonnet's score: odds ratio by point of score = 1.01, area under the roc curve = 0.64; modified Parsonnet's score: odds ratio by point of score = 1.05, area under the roc curve = 0.70). CONCLUSIONS: This study shows that the Parsonnet's scores are predictive, but that these scores remain imperfect: many risk factors are non significant, the initial Parsonnet's score has a moderate predictive value, and the modified Parsonnet's score is too complex (44 variables). Thus, we have built a new score for cardiac surgery in French adults.

Adult↗
PubMed2002

Predictive value of intraosseous venography before percutaneous vertebroplasty.

PURPOSE: Percutaneous vertebroplasty is a novel approach for treating patients with painful vertebral body compression fractures. The use of intraosseous venography before the percutaneous injection of polymethylmethacrylate (PMMA) is not universally accepted. The purpose of this study was to determine if intraosseous venography predicts PMMA flow characteristics when injected into a vertebral body. MATERIALS AND METHODS: One hundred thirty-five intraosseous venograms were obtained during 96 vertebroplasty procedures (39 thoracic, 57 lumbar) in 61 patients (49 women, 12 men; age, 36-94 y) over a 32-month period. All venograms were obtained by injecting water-soluble contrast material through the vertebroplasty needle that had been placed percutaneously via a transpedicular approach. The venograms were retrospectively reviewed by the authors and compared in a blinded fashion with the subsequent final vertebroplasty result. RESULTS: Several venographic patterns were observed: bilateral or unilateral marrow blush with or without venous filling, direct venous filling, leakage of contrast material through an endplate or cortical defect, and stasis within the marrow space. Venograms that demonstrated a bilateral marrow blush predicted flow of PMMA across the midline to adequately fill the contralateral hemivertebrae 95% of the time (40 of 42 cases). A unilateral marrow blush predicted the necessity of a second puncture 97% of the time (32 of 33 cases). Intraosseous venography predicted PMMA entering endplate/cortical defects in all cases (22 of 22) and venous structures in 29% (22 of 75) of cases. Direct venous filling was observed during two vertebroplasty procedures and gelatin foam embolization was performed before PMMA instillation. Stasis of contrast material in the marrow space was observed in 15 cases. Overall, in 83% (80 of 96) of the vertebroplasty procedures, intraosseous venography was believed to predict the flow characteristics of PMMA. CONCLUSION: Intraosseous venography provides useful information in predicting PMMA flow characteristics within the vertebral body and in predicting potential undesirable sites of cement deposition, such as through cortical defects and within venous structures.

Adult↗
PubMed2003

Assessment of basic human performance resources predicts operative performance of laparoscopic surgery.

BACKGROUND: Interest in laparoscopic surgery has prompted development of educational programs designed to teach and assess laparoscopic skills. Although these programs are beneficial, because of the inherent demands imposed by laparoscopy some aspects of operative performance might not improve with practice. This suggests that innate ability could predict level of operative skill. Assessment of operative and technical potential to date has relied largely on subjective rather than objective criteria. In this study, the relationships between objective measures of human basic performance resources (BPRs) and laparoscopic performance were evaluated using Nonlinear Causal Resource Analysis (NCRA), a novel predictive and explanatory modeling approach based on General Systems Performance Theory. STUDY DESIGN: Twenty urology residents were voluntary enrolled. Thirteen validated BPRs were measured and analyzed relative to operative laparoscopic performance (assessed by two experts) of two porcine laparoscopic nephrectomies (LN). The laparoscopic procedure, representing a High Level Task (HLT), was evaluated using a modified Global Rating of Operative Performance Scale. NCRA models were devised to predict performance of the HLT laparoscopic nephrectomies based on BPRs and to determine the limiting performance resource. RESULTS: NCRA models predicted excellent agreement with actual operative performance, suggesting that measures of innate ability (or BPRs) predicted performance of laparoscopic nephrectomy. In 65%, the prediction by NCRA was near identical to the expert rating on the HLT. In 25% of cases, NCRA overpredicted performance; in 10%, NCRA underpredicted performance of the HLT compared to the subjective ratings. Neuromotor channel capacity was the most common performance-limiting resource. CONCLUSIONS: Preliminary findings suggest objective prediction of laparoscopic performance with limiting resource diagnostics for an individual surgeon is possible and practical using appropriate new measurement and modeling methods. Selection of surgical candidates, training, and educational curriculum could be positively affected.

Adult↗
PubMed2004

Measures of anxiety: is there a difference in their ability to predict functioning at three-month follow-up among pain patients?

Independent investigators have found that pain is related to health anxiety, trait anxiety, pain-related anxiety, and anxiety sensitivity. To date, the relationship among these anxiety-related constructs has not been studied directly and little is known about their relative ability to predict adjustment to pain over time. This paper presents longitudinal data from measures given to 227 musculoskeletal pain patients. Patients were asked at the time of their first visit (T1) to a physiotherapy clinic to complete a questionnaire package including measures of these different forms of anxiety as well as pain severity, disability, negative affect, and perceived control. Approximately 3 months later (T2), 50% of patients responded to these same questionnaires. Results showed that correlations among the anxiety measures at T1 ranged from 0.35 to 0.56. Using multiple regression analyses, measures of T1 anxiety were each examined for their ability to predict unique variance in disability, negative affect, and perceptions of control measured at T1 and T2. At T1, after controlling for pain severity and other measures of anxiety, pain-related anxiety uniquely predicted both disability and negative affect, trait anxiety uniquely predicted negative affect and perceptions of control, and anxiety sensitivity uniquely predicted negative affect. At T2, after controlling for pain severity, other measures of anxiety and each respective measure of functioning at T1, health anxiety uniquely predicted disability and negative affect, although anxiety sensitivity also uniquely contributed to the prediction of negative affect. It is concluded that the importance of various forms of anxiety is dependent on the timeframe and outcome examined. Clinical implications of the findings as well as directions for future research are discussed.

Adult↗
PubMedDate not supplied

Predicting recovery using continuous low back pain outcome measures.

BACKGROUND CONTEXT: There is a lack of research evaluating multiple follow-up visits, specifically when using continuous outcome measures. Continuous outcome measures with several follow-up assessments would allow us to evaluate rate of recovery. PURPOSE: To predict low back pain outcomes based on the quantification of initial conditions. STUDY DESIGN/SETTING: This was a prospective study where patients were enrolled within the first month of low back pain symptoms and evaluated for 3 months. Patients were recruited from several primary care facilities. PATIENT SAMPLE: Thirty-two patients with local low back pain symptoms were recruited for the study. OUTCOME MEASURES: There were four major outcome measures, including functional performance probability, symptom intensity, impairment of activities of daily living, and a summary outcome measure. METHODS: Regression models were constructed using the initial conditions, including psychological, psychosocial, physical workplace, and personal factors, to predict the rate of recovery for each outcome measure. RESULTS: Twenty-eight patients completed the study. The r2 value for the rate of recovery regression models were 0.77 symptom intensity prediction, 0.85 activities of daily living prediction, 0.87 functional performance probability prediction, and 0.96 summary outcome measure prediction. Two functional performance patterns of recovery were found, including a steady improvement and a large jump in improvement. A discriminant function model identified the pattern of recovery in 91% of cases given initial conditions. CONCLUSIONS: Continuous outcome measures can be accurately predicted given the initial conditions.

Activities of Daily Living↗
PubMedDate not supplied

Conventional imaging and 2-deoxy-2-[(18)F]fluoro-D-glucose positron emission tomography for predicting the clinical outcome of patients with previously treated Hodgkin's disease.

PURPOSE: The aim of this study was to determine the ability of 2-deoxy-2-[(18)F]fluoro-d-glucose positron emission tomography (FDG-PET) to predict the clinical outcome of previously treated patients with Hodgkin's Disease (HD). PATIENTS AND METHODS: Thirty-two patients were studied with PET within a median interval of 5.2 months after treatment. Conventional imaging (CI) performed within two months before PET included 2.9+/-1.2 imaging tests/patient. To determine the independent ability of FDG-PET to predict the clinical outcome, PET images were reread without knowledge of CI and clinical history. Study end points were disease-free survival, or clinical evidence of disease or death. PET and CI stages were also compared for each patient. RESULTS: Using the clinical outcome as gold standard after a median follow-up of 14 months, 21 of 32 patients (65%) were considered disease-free while 11 of 32 patients (35%) had evidence for disease or had died. The predictive accuracy of PET was 91% vs. 66% for conventional imaging (P<0.05). The positive predictive value (PPV) was also significantly higher for PET (79% vs. 50%, P<0.05), while its negative predictive value (NPV) tended to be higher than that of CI (100% vs. 86%, P=0.08). Kaplan-Meier analysis for disease-free survival showed a significant difference between PET-negative and -positive results. No such difference was observed between CI-positive and -negative results (P=0.35). CONCLUSION: Whole-body FDG-PET imaging modified the clinical stage in 28% of patients. Moreover, FDG-PET predicted patient outcome with a higher predictive accuracy than CI. This superior prognostic accuracy was achieved with a single FDG-PET study vs. 2.9+/-1.2 CI procedures/patient.

Adolescent↗
PubMed1999

Biochemical markers can predict the response in bone mass during alendronate treatment in early postmenopausal women. Alendronate Osteoporosis Prevention Study Group.

Data from the Danish cohort (n = 67) of a multicenter trial of oral alendronate in the prevention of postmenopausal osteoporosis were used to evaluate the capacity of the biochemical markers to predict changes in bone mineral density (BMD). A panel of markers were measured: serum N-terminal midfragment osteocalcin (N-MID OC); serum total osteocalcin (total OC); bone-specific alkaline phosphatase (BSAP); serum and urine C-telopeptides of type I collagen (sCL and uCL); urine N-telopeptide crosslinks of type I collagen (NTX); and deoxypyridinoline (dPyr). The correlation between change from baseline at months 3-12 in total OC, N-MID OC, sCL, uCL, and NTX and 2 year response in spine BMD ranged from r = -0.45 to r = -0.78 (p < 0.001), and from r = -0.38 to r = 0.10 (n.s. to p < 0.002) for BSAP and dPyr. Sensitivity and specificity were used to assess the accuracy of change from baseline at month 6 in the biochemical markers for predicting prevention of bone loss in the spine over 2 years. The cutpoints used were a 30% (N-MID OC) or 50% (all other markers) decrease from baseline. Sensitivity levels were 82% (N-MID OC), 98% (total OC), 78% (sCL and NTX), and 89% (uCL). Specificities were 91% (N-MID OC), 59% (total OC), 100% (sCL), 71% (uCL), and 84% (NTX). Positive predictive values were 95% (N-MID OC), 82% (total OC), 100% (sCL), 87% (uCL), and 90% (NTX). In comparison, the predictive capacities of change from baseline at year 2 in hip BMD in predicting prevention of bone loss at the spine were similar: sensitivity, 82%; specificity, 55%; and positive predictive value, 79%. In conclusion, short-term changes in biochemical markers were valid predictors of long-term changes in BMD. Short-term changes in the sensitive biochemical markers revealed a predictive capacity similar to bone densitometry at the hip measured over 2 years. The sensitive biochemical markers offered a fast and valid alternative to bone densitometry for monitoring of alendronate treatment.

Absorptiometry, Photon↗
PubMed2004

Predicting final disposition after stroke using the Orpington Prognostic Score.

BACKGROUND: Prediction of outcome after stroke is important for triage decisions, prognostic estimates for family and for appropriate resource utilization. Prognostication must be timely and simply applied. Several scales have shown good prognostic value. In Calgary, the Orpington Prognostic Score (OPS) has been used to predict outcome as an aid to rehabilitation triage. However, the OPS has not been assessed at one week for predictive capability. METHODS: Among patients admitted to a sub-acute stroke unit, OPS from the first week were examined to determine if any correlation existed between final disposition after rehabilitation and first week score. The predictive validity of the OPS at one week was compared to National Institute of Health Stroke Scale (NIHSS) score at 24 hours using logistic regression and receiver operator characteristics analysis. The primary outcome was final disposition after discharge from the stroke unit if the patient went directly home, or died, or from the inpatient rehabilitation unit. RESULTS: The first week OPS was highly predictive of final disposition. However, no major advantage in using the first week OPS was observed when compared to 24h NIHSS score. Both scales were equally predictive of final disposition of stroke patients, post rehabilitation. CONCLUSIONS: The first week OPS can be used to predict final outcome. The NIHSS at 24h provides the same prognostic information.

Activities of Daily Living↗
PubMed1998

Predicting hematological toxicity (myelosuppression) of cytotoxic drug therapy from in vitro tests.

Several clinical oncology units are studying the roles of in vitro hematotoxicology in phase I evaluations. At the same time, the European Center for the Validation of Alternative Methods (ECVAM) is supporting a validation study of the CFU-GM assay. It is important that these activities be coordinated so that high performance, optimized technical protocols are used for prospective and retrospective clinical evaluations. The EROTC, the NCI and ECVAM could provide support for these coordinated efforts. There is an opportunity for medical oncologists involved in early clinical trials to participate in the evaluation of in vitro tests and their clinical application . Fundamental to acceptance of these assays by oncologists and regulatory scientists, they must predict clinical outcome for myelosuppressive agents and then improve phase I design and performance. These achievements would justify more aggressive dose escalation schemes using guidance from in vitro studies without compromising patient safety. Success in predicting neutropenia might also stimulate the research required to understand how to predict other hematologic toxicities, such as a thrombocytopenia. The complexity of a validation study in hematotoxicology is that it seeks to predict the level of exposure that causes neutropenia, in contrast to other validation studies that have sought to classify a xenobiotic as toxic or not. It may be that the clinical relevance of a new assay is not just a yes-no answer. This important distinction came from the realization that the xenobiotic tolerance in other organ systems of the body must be the same or greater than marrow in order for myelosuppression to be a clinical consequence of exposure. Pharmacological principles of system exposure and toxicity that are integrated into the prediction model provide the links to clinical oncology. It is also important to anticipate future applications of in vitro hematotoxicology. If the maximum tolerated level of drug exposure for human hematopoietic cells can be predicted, then in vitro hematotoxicology could play an important role in new drug discovery. One concept involves screening for compounds that show efficacy at the IC level that predicts maximum tolerated exposure levels in the human. 'Therapeutic index based' drug discovery has been applied to the tallimustine family with some success.

Animals↗
PubMed2004

Maximum P-wave duration and P-wave dispersion predict recurrence of paroxysmal atrial fibrillation in patients with Wolff-Parkinson-White syndrome after successful radiofrequency catheter ablation.

BACKGROUND: Identification of patients at risk for PAF recurrence after AP ablation is important because of the necessity for additional therapies. OBJECTIVES: To determine whether Maximum P-wave duration (Pmax) and P-wave dispersion (Pd ) detected on surface ECG after successful accessory pathway (AP) ablation can predict the recurrence of paroxysmal atrial fibrillation (PAF). METHODS: Seventy-eight patients with Wolff-Parkinson-White (WPW) syndrome who had at least one documented PAF episode and underwent catheter ablation were enrolled. Pmax, minimum P-wave duration (Pmin) and Pd were determined on a surface ECG recorded on a high resolution computer screen on day 2 after ablation of the AP. RESULTS: There was no significant difference in terms of basic clinical data and electrophysiological findings between patients with (Group-1, n = 19) and without (Group-2, n = 59) recurrence of PAF during follow-up of 21 +/- 10 months. Pmax and Pd were significantly higher in Group-1 than Group-2 (120 +/- 15 vs. 96 +/- 10 ms and 47 +/- 12 vs. 25 +/- 7 ms, respectively; p < 0.001 for both). Pmin didn't differ significantly. A Pmax value of > or = 103 ms separated Group-1 from Group-2 with a sensitivity of 84.2%, specificity of 72.9%, positive predictive value of 50%, and negative predictive value of 93.5%. A Pd value of > or = 32.5 ms separated Group-1 from Group-2 with a sensitivity of 89.5%, specificity of 84.7%, positive predictive value of 65.4%, and negative predictive value of 96.2%. Pmax (p < 0.010) and Pd (p < 0.001) were found to be significant univariate predictors of PAF, whereas only Pd remained significant in multivariate analysis (p = 0.037). CONCLUSION: Pd > or = 32.5 ms and Pmax > or = 103.0 ms predict the recurrence of PAF after ablation with acceptable positive and negative predictive values. Pd > or = 32.5 ms is an independent predictor of recurrence of PAF after catheter ablation in patients with WPW syndrome.

Adolescent↗
PubMed2004

Comparison of the use of liver models for predicting drug clearance using in vitro kinetic data from hepatic microsomes and isolated hepatocytes.

PURPOSE: To compare three liver models (well-stirred, parallel tube, and dispersion) for the prediction of in vivo intrinsic clearance (CL(int)), hepatic clearance (CLh). and hepatic availability (Fh) of a wide range of drugs in the rat using in vitro data from two in vitro sources. METHODS: In vitro CL(int) was obtained from studies using isolated rat hepatocytes (35 drugs) or rat liver microsomes (52 drugs) and used to predict in vivo CL(int) using reported scaling factors, and subsequently CLh and Fh were predicted based on the three liver models. In addition, in vivo CL(int) values were calculated from the reported values of CLh based on each of the three models. RESULTS: For all of the parameters, predictions from hepatocyte data were consistently more accurate than those from microsomal data. Comparison of in vitro and in vivo CL(int) values demonstrated that the dispersion model and the parallel tube model were comparable and more accurate (less bias, more precise) than the well-stirred model. For CLh and Fh prediction, the three models performed similarly. CONCLUSIONS: Considering the statistics of the predictions for three liver models, the use of parallel tube model is recommended for the evaluation of in vitro CL(int) values both from microsomes and hepatocytes. However, for the prediction of the in vivo drug (hepatic) clearance from in vitro data, as there are minimal differences between the models, the use of the well-stirred liver model is recommended.

Algorithms↗
PubMed2003

Predictive value of pretransplantation cyclosporine pharmacokinetic studies on initial post-transplantation dosing in pediatric kidney allograft recipients.

Despite the introduction of a variety of new immunosuppressive agents, cyclosporine A (CsA) has maintained a strong position in pediatric transplantation (Tx). Post-Tx dosing with CsA is a challenging task because of the narrow therapeutic window of the drug, the great individual variability of metabolism and the lack of consensus about the optimal dosage and targeted blood concentration. Sufficient administration of CsA may be protective against acute rejections and other early complications after Tx, which is crucial for the long-term survival of the graft. Individual doses based on pre-Tx pharmacokinetic studies might be helpful in achieving optimal early concentrations of CsA. To asses the usefulness of pharmacokinetic studies, we retrospectively compared the post-Tx doses administered with the individually predicted doses between 1988 and 1998. Multiple regression of data on 65 de novo renal transplant recipients, 1.1-15.5 yr old, was used to analyze the significance of the predicted dose, trough blood concentration of CsA (B-CsA), serum creatinine and age at the time of Tx in explaining the doses used during the first three post-Tx weeks. Patients were grouped according to age (<2, 2-8 and >8 yr), according to the predicted dose (within or outside +/-25% of age-group average), and according to the oral formulation of CsA. Standard dosing scheme was simulated by using age-specific average doses in the place of the individual predicted doses. Administered doses of CsA were high [averaging 22.6 (504), 20.7 (484), and 12.4 mg/kg/d (329 mg/m2/d) for patients <2, 2-8, and >8 yr old] but the average B-CsA remained in the target range of 250-450 microg/L. The predicted dose and age were significant parameters in explaining the administered doses during the first 3 wk after Tx. B-CsA and S-creatinine were non-significant. The predicted doses were used to initiate the dosing of CsA after Tx (R2 = 0.70) and adjustments to dosing were made during the next weeks (R2 = 0.59, 0.52). Multiple regression model showed better fit for 60% of our patients, who had atypical predicted doses (R2 = 0.74, 0.60, 0.64 for first, second and third post-Tx weeks, respectively), most remarkably in patients <2 yr of age, than for the study population as a whole. A simulated standard dose was not able to explain the administered doses of CsA. In conclusion, pre-Tx pharmacokinetic studies are valuable for determining individual post-Tx starting doses, especially for those patients who need high or low doses of CsA. Individual dosing led to relatively high initial CsA doses, which could be significant for the long-term survival of the graft.

Adolescent↗
PubMed1994

The predictive value of post-operative intraocular pressures following trabeculectomy.

The value of post-operative intraocular pressure (IOP) in predicting the outcome of trabeculectomy was investigated in a retrospective study of single eyes of 203 Caucasian patients with uncomplicated chronic open angle glaucoma from the Birmingham and Midland Eye Hospital. Post-operative IOPs were recorded on day 1, at 2 weeks, and at 3, 6, 12 and 24 months. Surgical failure, defined as an IOP of 21 mmHg or above throughout the study period, occurred in 66 eyes by 24 months (32.5% failure). Discriminant analysis for the first day post-operative IOP showed a reliability of prediction of success (RPS) and failure (RPF) of 76.4% and 74.4% respectively, with an accuracy of prediction of success (APS) and failure (APF) of 92.6% and 42.6%. At 2 weeks, APS remained high (90.3%) and APF increased with time (63.2%). Certainty of success prediction at any stage is high and certainty of failure prediction becomes greater with time. In terms of IOP on the first post-operative day, 92.6% of successes may be correctly predicted if the IOP < 17 mmHg and 42.6% of failures may be predicted if the IOP > or = 17 mmHg. This study suggests that identification of patients at risk of failure on the basis of IOP in the early post-operative period is possible and that closer follow-up and early medical or surgical intervention may be indicated.

Adult↗
PubMed2002

Early prediction of treatment response to high-dose salvage chemotherapy in patients with relapsed germ cell cancer using [(18)F]FDG PET.

To assess the ability of [(18)F]fluorodeoxyglucose positron emission tomography for the early prediction of response in patients with relapsed metastatic germ cell tumours undergoing salvage high-dose chemotherapy. The role of positron emission tomography was compared with established means of tumour response assessment such as CT scans/MRI and serum tumour marker changes. In addition, positron emission tomography was compared with a current prognostic score which differentiates three prognostic groups with failure-free survival rates ranging from 5-50%. [(18)F]fluorodeoxyglucose uptake of metastases from germ cell tumours as well as CT scans and serum tumour marker were acquired after 2-3 cycles of induction chemotherapy but before the start of high-dose chemotherapy and CT scans/serum tumour marker were compared with the baseline examinations in 23 patients with relapsed germ cell tumours. To evaluate the validity of early response prediction by positron emission tomography, radiological monitoring and serum tumour marker decline, histopathologic response after resection of residual masses and/or the clinical course over 6 months after the end of treatment (relapse vs freedom of progression) were used. Overall, 10 patients (43%) achieved a marker-negative partial remission, three (13%) a marker-positive partial remission, five (22%) a disease stabilization and five (22%) progressed during treatment. Nine patients (39%) remained progression-free over 6 months following treatment, whereas 14 (61%) progressed. The outcome of high-dose chemotherapy was correctly predicted by positron emission tomography/CT scan/serum tumour marker in 91/59/48%. Eight patients with a favourably predicted outcome by CT scans plus serum tumour marker but a positive positron emission tomography prior to high-dose chemotherapy, failed treatment. This results in the following sensitivities/specificities for the prediction of failure of high-dose chemotherapy: positron emission tomography 100/78%; radiological monitoring 43/78%; serum tumour marker 15/100%. The positive and negative predictive values of positron emission tomography were 88 and 100%, respectively. As compared with the prognostic score, positron emission tomography was correctly positive in all patients of the three risk groups who failed treatment. In addition, a negative positron emission tomography correctly predicted a favourable outcome in the good and intermediate group. [(18)F]fluorodeoxyglucose positron emission tomography imaging can be used to assess response to chemotherapy in patients with relapsed germ cell tumours early in the course of treatment and may help to identify patients most likely to achieve a favourable response to subsequent high-dose chemotherapy. In patients with response to induction chemotherapy according to CT scans or serum tumour marker evaluation, positron emission tomography seems to add information to detect patients with an overall unfavourable outcome. It may also be a valuable addition to the prognostic model particularly in the good and intermediate group for further selection of patients who will profit from high-dose chemotherapy.

Adult↗
PubMed2003

External validity of a prediction rule for residual mass histology in testicular cancer: an evaluation for good prognosis patients.

We assessed the external validity of a prediction rule for nonseminomatous testicular cancer patients. The rule was developed to predict the probability of retroperitoneal metastases being benign (only necrosis/fibrosis) after chemotherapy treatment. Patients with a high probability of benign residual masses might be offered surveillance as opposed to patients with a low probability, who should undergo retroperitoneal lymph node dissection (RPLND). We compared the observed histology with the predicted probability in 105 patients with good prognosis germ cell cancer who underwent RPLND between 1995 and 1998. We found that predicted probabilities higher than 5% were in good agreement with the observed frequencies of benign masses. The area under the receiver operating characteristic curve was 0.76, suggesting that the rule could reasonably discriminate between benign masses and tumour. However, nearly all predicted probabilities (n=101) were lower than 70%, which might be considered as the lowest value at which surveillance offers a reasonable alternative to RPLND. Further, 35% of patients currently under surveillance (84 out of 241) had predicted probabilities lower than 70%. In conclusion, the clinical relevance of the prediction rule was limited for the patients who underwent RPLND; use of the rule would change the policy from RPLND to surveillance in only a few. On the other hand, the rule might support selection of patients for RPLND, who currently are under surveillance.

Fibrosis↗
PubMed2001

The validity of predicted body fat percentage from body mass index and from impedance in samples of five European populations.

OBJECTIVES: To test and compare the validity of a body mass index (BMI)-based prediction equation and an impedance-based prediction equation for body fat percentage among various European population groups. DESIGN: Cross-sectional observational study. SETTINGS: The study was performed in five different European centres: Maastricht and Wageningen (The Netherlands), Milan and Rome (Italy) and Tampere (Finland), where body composition studies are routinely performed. SUBJECTS: A total of 234 females and 182 males, aged 18-70 y, BMI 17.0-41.9 kg/m(2). METHODS: The reference method for body fat percentage (BF%(REF)) was either dual-energy X-ray absorptiometry (DXA) or densitometry (underwater weighing). Body fat percentage (BF%) was also predicted from BMI, age and sex (BF%(BMI)) or with a hand-held impedance analyser that uses in addition to arm impedance weight, height, age and sex as predictors (BF%(IMP)). RESULTS: The overall mean (+/-s.e.) bias (measured minus predicted) for BF%(BMI) was 0.2+/-0.3 (NS) and-0.7+/-0.3 (NS) in females and males, respectively. The bias of BF%(IMP) was 0.2+/-0.2 (NS) and 1.0+/-0.4 (P<0.01) for females and males, respectively. There were significant differences in biases among the centres. The biases were correlated with level of BF% and with age. After correction for differences in age and BF% between the centres the bias of BF%(BMI) was not significantly different from zero in each centre and was not different among the centres anymore. The bias of BF%(IMP) decreased after correction and was significant from zero and significant from the other centres only in males from Tampere. Generally, individual biases can be high, leading to a considerable misclassification of obesity. The individual misclassification was generally higher with the BMI-based prediction. CONCLUSIONS: The prediction formulas give generally good estimates of BF% on a group level in the five population samples, except for the males from Tampere. More comparative studies should be conducted to get better insight in the generalisation of prediction methods and formulas. Individual results and classifications have to be interpreted with caution.

Absorptiometry, Photon↗