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At least 937 records · Page 52Linked to original sources
PubMed2004

A prospective comparison of 3 diagnostic methods to evaluate ejaculatory duct obstruction.

PURPOSE: Various diagnostic tests are available to evaluate patients with ejaculatory duct obstruction (EDO). However, the most accurate diagnostic technique, defined as the one that best predicts a successful outcome after ejaculatory duct resection, is unclear. We prospectively performed transrectal ultrasound (TRUS) and 3 other tests in men with EDO and determined their relative value in this diagnosis. MATERIALS AND METHODS: Patients with suspected EDO on clinical evaluation that included TRUS proceeded to further intraoperative evaluation with duct chromotubation, seminal vesicle aspiration and seminal vesiculography. A comparative analysis of findings from each technique was performed and the success of subsequent transurethral resection procedures was assessed. RESULTS: All 25 patients had evidence of EDO on diagnostic TRUS, a finding that merited further evaluation with other modalities. However, TRUS findings correlated poorly with those of the other diagnostic tests. Obstruction on TRUS was confirmed in only 52%, 48% and 36% of vesiculography, seminal vesicle aspiration and duct chromotubation studies, respectively. A better correlation was observed between the dynamic tests of duct chromotubation and seminal vesiculography. Based on all diagnostic tests only 12 patients (48%) proceeded to duct resection, of whom 10 (83%) showed significant improvement in semen analysis parameters or clinical symptoms after the procedure. CONCLUSIONS: A comparative analysis of 4 diagnostic techniques suggests that TRUS alone has poor specificity for EDO evaluation. Incorporating dynamic tests into the algorithm of EDO diagnosis may decrease unnecessary duct resection procedures and improve the success of the resection procedures that are indicated.

Adolescent↗
PubMed2003

Diagnostic laparoscopy in abdominal stab wounds: a prospective, randomized study.

BACKGROUND: The optimal strategy for identifying patients with abdominal stab wounds requiring surgical repair has not been defined. The potential benefits of diagnostic laparoscopy by incorporating it into the routine diagnostic workup of patients with anterior abdominal stab wounds was evaluated in a two-layer, randomized study. METHODS: From May 1997 through January 2002, stable patients without peritonitis but with demonstrated peritoneal violation were randomized (A) to exploratory laparotomy (AEL) (n = 23) or diagnostic laparoscopy (ADL) (n = 20). Simultaneously, patients with equivocal peritoneal violation on local wound exploration were randomized (B) to diagnostic laparoscopy (BDL) (n = 28) or expectant nonoperative management (BNOM) (n = 31). Hospital morbidity, length of stay, and costs were primary endpoints, with postdischarge disability being a secondary endpoint. RESULTS: In patients with peritoneal penetration (AEL vs. ADL), there were minimal differences in the therapeutic operation rate (8 of 23 [AEL] vs. 8 of 20 [ADL], p = 0.761), mortality (none), morbidity (3 of 23 vs. 2 of 20, p = 0.999), hospital stay (mean +/- SD) (5.7 +/- 2.5 vs. 5.1 +/- 4.0 days, p = 0.049), hospital costs (4.6 +/- 1.3 vs. 4.8 +/- 1.9 x 1,000 EUR, p = 0.576), and length of sick leave (34 +/- 12 vs. 29 +/- 11 days, p = 0.305). In patients with equivocal peritoneal penetration (BDL vs. BNOM), laparoscopy found more mostly minor organ injuries (7 of 28 [BDL] vs. 1 of 31 [BNOM], p = 0.022) with no significant difference in therapeutic operations (3 of 28 vs. 1 of 31, p = 0.337) or morbidity (3 of 28 vs. 0 of 31, p = 0.101), but was associated with increased length of stay (2.6 +/- 2.1 vs. 1.9 +/- 1.8 days, p = 0.022), hospital costs (4.2 +/- 1.3 vs. 1.5 +/- 1.1 x 1,000 EUR, p = 0.000), and sick leave requirements (18 of 23 vs. 8 of 28 of eligible patients, p = 0.001). CONCLUSION: In patients with demonstrated peritoneal violation, laparoscopy offers little benefit over exploratory laparotomy. In patients with equivocal peritoneal penetration on local wound exploration, laparoscopy detects more mostly minor organ injuries than expectant nonoperative management but is associated with increased hospital stay, costs, and sick leave requirements. Overall, diagnostic laparoscopy cannot be recommended as a routine diagnostic tool in anterolateral abdominal and thoracoabdominal stab wounds.

Abdominal Injuries↗
PubMed2025

Redefining ALS: Large-scale proteomic profiling reveals a prolonged pre-diagnostic phase with immune, muscular, metabolic, and brain involvement.

BACKGROUND: Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder with a largely unknown duration and pathophysiology of the pre-diagnostic phase, especially for the common non-monogenic form. METHODS: We leveraged the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort with up to 30 years of follow-up to identify incident ALS cases across five European countries. Pre-diagnostic plasma samples from initially healthy participants underwent high-throughput proteomic profiling (7,285 protein markers, SomaScan). Cox proportional hazards models based on 4,567 participants (including 172 incident ALS cases) were used to identify protein biomarkers associated with future ALS diagnosis. Top results were indirectly validated in two independent case-control studies of prevalent ALS (n=417 ALS, 852 controls). Functional annotation included cross-disease comparisons, gene set and tissue enrichment testing, organ-specific proteomic clocks, and the application of large-language models (LLM). FINDINGS: Five proteins (SECTM1, CA3, THAP4, KLHL41, SLC26A7) were identified as significant pre-diagnostic ALS biomarkers (FDR=0.05), detectable approximately two decades before diagnosis. Of these, all except SECTM1 were indirectly validated in independent cohorts of prevalent ALS cases, supporting their clinical significance. Additionally, 22 nominally significant (p<0.05) pre-diagnostic biomarkers were FDR-significant in prevalent ALS with consistent effect directions. Cross-disease comparisons with pre-diagnostic Parkinson's and Alzheimer's disease suggested a largely specific pre-diagnostic ALS biomarker signature. Gene ontology and tissue enrichment highlighted early involvement of immune, muscle, metabolic, and digestive processes. Furthermore, analyses of proteomic clocks revealed accelerated aging in brain-cognition, immune, and muscle tissues before clinical diagnosis. Druggability and LLM analyses revealed possible therapeutic targets and novel strategies, emphasizing translational relevance. INTERPRETATION: Our study provides first evidence of ultra-early molecular changes in common ALS up to two decades prior to clinical onset, mainly affecting immune, muscle, metabolic, digestive, and cognitive systems. Our study nominates several compelling candidates for risk stratification studies and novel therapeutic targets for early intervention. FUNDING: Clinical Research in ALS and Related Disorders for Therapeutic Development (CreATe) Consortium, Cure Alzheimer's Fund, Michael J Fox Foundation, Interdisciplinary Centre for Clinical Research, University M&#xfc;nster.

Journal Article↗
PubMed1997

Determination of independent risk factors and comparative analysis of diagnostic methods for immediate type latex allergy in spina bifida patients.

BACKGROUND: Development of allergy to natural rubber latex in spina bifida patients is determined by several risk factors, such as age, number of interventions and atopic disease that are, however, interdependent. Furthermore, several diagnostic procedures have been analysed, but a comprehensive analysis of their diagnostic significance is lacking. OBJECTIVE: To determine the independent major risk factor(s) for development of natural rubber latex allergy and the most valuable diagnostic procedure. METHODS: In aselectively collected spina bifida patients, we correlated existing natural rubber latex allergy with age, sex, atopy and the number of hospitalizations and of surgical interventions in appropriately matched subgroups. Allergy to natural rubber latex was established by application of a latex glove fragment on the skin. Skin-prick tests with glove eluate, a natural latex extract and a commercial latex extract were carried out as were specific IgE measurements by radioimmuno assay (RAST-CAP). The results of the latex application test are compared with the other diagnostic methods. RESULTS: Out of 74 fully evaluated patients, 17 had a positive application test. The number of surgical interventions correlates strongly with the presence of natural rubber latex allergy (P<0.0002), independent of age, sex and presence of atopy. Skin-prick tests with unstandardized allergens made from known high allergenic latex gloves represent the most sensitive diagnostic method, with the highest negative predictive value and a specificity of 0.95. RAST-CAP was the next best method with a specificity of 0.93, a sensitivity of 0.89 and a negative predictive value of 0.97. CONCLUSION: The number of surgical interventions is the major independent determining factor for allergy to natural rubber latex in spina bifida patients. Unstandardized skin-prick tests are the most sensitive and specific diagnostic tool, but RAST-CAP is almost equally performant and therefore a valid alternative.

Adolescent↗
PubMed2006

Age changes the diagnostic accuracy of mean profile and nadir growth hormone levels after oral glucose in postoperative patients with acromegaly.

BACKGROUND: This analytical, retrospective study was designed to select cut-off thresholds of mean GH levels during a diurnal profile and nadir GH levels after oral glucose tolerance test (OGTT) according to age to diagnose surgical remission of acromegaly. METHODS: One hundred forty-one patients (76 women, aged 44 +/- 15 years and 65 men, aged 43 +/- 13 years) were included in this study. For the purpose of this study, remission was based on insulin-like growth factor-I (IGF-I) levels in the normal range for age. Diagnostic accuracy was analysed by receiving-operator characteristics (ROC) curves in the entire series, and in young (20-40 years), middle-aged (41-60 years) and older patients (> 60 years), separately. RESULTS: Sixty patients (42.6%) had normal IGF-I levels after surgery. In the entire series, in young and in middle-aged patients, the ROC analysis showed that optimum cut-off for mean GH levels was 2.3 microg/l (diagnostic accuracy range, 94-97%) whereas that for nadir GH after OGTT were, respectively, 0.85, 0.9 and 0.8 microg/l (diagnostic accuracy range, 90-95%). In the older patients, the optimum cut-off selected for mean GH levels was 1.4 microg/l and that for nadir GH after OGTT was 0.5 microg/l (diagnostic accuracy, 100% for both). The comparative analysis of the ROC curves did not show any significant difference between mean GH and nadir GH after OGTT (P = 0.21). CONCLUSIONS: The criteria currently accepted for diagnosing post-surgical remission of acromegaly have high diagnostic accuracy only in the patients aged below 60 years. In older patients, lower cut-offs (i.e. = 1.4 microg/l for fasting GH and = 0.5 microg/l for nadir GH after OGTT) predict normal IGF-I levels. Mean GH levels during a diurnal profile have similar diagnostic accuracy of nadir GH levels after OGTT. This suggests that OGTT is not necessary to establish surgical cure.

Acromegaly↗
PubMed2007

A randomized controlled trial of the diagnostic accuracy of internet-based telepathology compared with conventional microscopy.

AIMS: To compare the diagnostic accuracy of internet-based virtual microscopy with conventional light microscopy, in the context of renal biopsies assessed by participants in the UK National Renal Pathology External Quality Assessment (EQA) Scheme. METHODS AND RESULTS: 'Virtual slides' of current EQA cases were made available over the internet to participants in the scheme. The approach permitted what may reasonably be described as a randomized controlled trial of the diagnostic accuracy of this mode of telepathology, in the context of renal pathology. No significant difference in diagnostic accuracy could be detected between the diagnoses proffered on the basis of virtual slides and conventional slides; but using virtual slides took pathologists considerably longer. CONCLUSIONS: This result provides some encouragement for the implementation of such virtual slide-based telepathology systems. However, in failing to detect a difference, equivalence of diagnostic accuracy has not been proved; nor has the relevance of this result to other fields of histopathology been demonstrated. A decision to implement a diagnostic telepathology system requires consideration of numerous factors beyond diagnostic accuracy, including financial, legal, professional and ethical issues.

Diagnosis↗
PubMed1992

Evaluation of diagnostic tests using relative operating characteristic (ROC) curves and the differential positive rate. An example using the total serum bile acid concentration and the alanine aminotransferase activity in the diagnosis of canine hepatobiliary diseases.

The value of a diagnostic test depends on most cases on its ability to discriminate between patients with and without a certain disease. One way of evaluating a diagnostic test is to use the relative operating characteristic curve (ROC curve) and the differential positive rate (DPR). The ROC curve displays the relationship between the true positive ratio and the false positive ratio for a range of cutoff values and it can be used to compare various diagnostic tests under equivalent conditions (equal true positive ratios or false positive ratios) and over the entire range of cutoff values. The DPR is the difference between the true positive ratio and the false positive ratio at various cutoff values and it can be used to obtain the cutoff value associated with the highest sensitivity and specificity. The purpose of this study was to describe the evaluation and comparison of diagnostic tests using ROC curves and DPR. Eventually, the positive and negative predictive values were used to assess the differences between the sensitivity and specificity obtained when the upper limit of the reference interval, or the optimal cutoff value indicated by the DPR, was used as cutoff value. To illustrate the methods, the 2 h post-prandial total serum bile acid concentration (PSBA) and the alanine aminotransferase activity (ALAT) in the diagnosis of primary or secondary hepatobiliary diseases in dogs were used. The ROC curves showed, as expected from previous studies, that PSBA was superior to ALAT in diagnosing dogs with hepatobiliary diseases. Using DPR, the optimal cutoff value for PSBA was suggested to be 15.48 mumol/l. Compared to the traditionally used cutoff value of 22.24 mumol/l, no decisive difference in the positive predictive values were observed. However, the cutoff value of 15.48 mumol/l appeared to produce higher negative predictive values compared to a cutoff value of 22.24 mumol/l. Seemingly, ROC curves and DPR are simple methods useful to the evaluation of diagnostic tests and due to the simplicity, there seems to be a great potential for these methods in the evaluation of diagnostic tests in veterinary medicine.

Alanine Transaminase↗
PubMed2006

Evaluation of the diagnostic value of serum tumor markers, and fecal k-ras and p53 gene mutations for pancreatic cancer.

OBJECTIVE: To evaluate the diagnostic value for pancreatic cancer of four serum tumor markers, carbohydrate antigen (CA) 199, CA242, CA50 and carcino-embryonic antigen (CEA), and fecal k-ras and p53 gene mutations. METHODS: From February 2002 to March 2004, 136 patients were consecutively diagnosed with pancreatic cancer in the three participating medical centers. The diagnosis was confirmed by pathology in 53 patients, of whom five were excluded because they did not have measurement of serum tumor marker. The remaining 48 patients comprised the case group in the study. Ninety-six patients with benign digestive diseases diagnosed during the same period were recruited as control subjects. They were matched by sex and age. In both groups, serum CA199, CA242, CA50 and CEA were measured by ELISA, and fecal k-ras and p53 gene mutations were measured by PCR-restriction fragment length polymorphism and PCR-single strand conformational polymorphism, respectively. The receiver operating characteristic (ROC) curve and area under the curve (AUC) were used to compare their diagnostic value, as well as the sensitivity, specificity and likelihood ratio. Moreover, independent and sensitive tests from these non-invasive approaches were selected to form a parallel test that may have further improved sensitivity for diagnosis of pancreatic cancer. RESULTS: The AUC of serum CA199 and CA242 were 0.821 (95%CI 0.725-0.917) and 0.821 (95%CI 0.723-0.919), respectively. The optimal diagnostic value of serum CA199 for pancreatic cancer was 93 U/mL, with a sensitivity of 73.7% and specificity of 91.4%. The positive likelihood ratio of CA199 was 8.57, and the negative likelihood ratio was 0.29. The optimal diagnostic value of serum CA242 was 25 U/mL, with a sensitivity of 71.1% and specificity of 93.5%. The positive likelihood ratio of CA242 was 10.94, and the negative likelihood ratio was 0.31. The sensitivity of fecal k-ras gene mutation for diagnosis of pancreatic cancer was 77.4%, and the specificity was 81.2%. The positive and negative likelihood ratios of fecal k-ras gene mutation were 4.12 and 0.28, respectively. The sensitivity and specificity of fecal p53 gene mutation were 25.8% and 95.3%, respectively, and its positive and negative likelihood ratios were 5.49 and 0.78. The rate of fecal k-ras mutation was higher in patients with benign pancreatic diseases (57.14%) than that of controls with non-pancreatic disorders. The values of serum tumor markers and fecal k-ras and p53 gene mutation rates were not significantly different in subgroups according to site or stage of pancreatic cancer. The sensitivity and specificity of the parallel test of serum CA199 and fecal k-ras gene mutation were 94.06% and 74.22%, respectively, while the sensitivity and specificity of the parallel test of serum CA242 and fecal k-ras were 93.47% and 75.92%, respectively. CONCLUSIONS: Serum CA199 and CA242 are valuable diagnostic tools for pancreatic cancer. The diagnostic value is further improved when they are combined with fecal k-ras gene mutation measurement.

Aged↗
PubMed1983

Experience with diagnostic peritoneal lavage in blunt abdominal trauma.

Fifty-one patients who had suffered blunt abdominal trauma were assessed clinically and with diagnostic peritoneal lavage. The latter has been shown to be a safe, accurate means of determining the presence or absence of haemoperitoneum. Furthermore, in patients with disturbed conscious states, the initial clinical assessment has been found to be inaccurate and the performance of diagnostic peritoneal lavage has resulted in a statistically significant increase in diagnostic accuracy (P = 0.006). However, in patients with a normal conscious state, the improvement in diagnostic accuracy achieved by the performance of diagnostic peritoneal lavage was not statistically significant. The technique of diagnostic peritoneal lavage is discussed in detail.

Abdominal Injuries↗
PubMed1999

Cerebrovascular disease as a general medicine discharge diagnosis: assessment of diagnostic agreement on case note review.

BACKGROUND: Accurate clerical coding of discharge diagnoses is important partly because results may be used to derive a recommended costing for hospital length of stays (LOS). Some authors think that discharge coding undertaken by clinicians will result in less diagnostic misclassification than clerical coding. This presupposes a high degree of between-observer diagnostic agreement between clinicians. AIMS: To compare discharge coding undertaken by two general physicians, for patients receiving a clerical discharge code of cerebrovascular disease. The recommended LOS was then calculated from each observer's discharge codes using the Physicians Diagnosis Related Group Working Guidebook. RESULTS: Eighty-two cases were coded as stroke by the clerical coder. Both medical coders agreed with this diagnosis in 68 (83%) of these cases. The corresponding figure for cases coded by the clerical coder as transient cerebral ischaemia was 47% (32/68) agreement between all three observers. Correcting for chance agreement between medical observers using the kappa statistic, a value of 0.64 was obtained for the combined stroke and transient cerebral ischaemia discharges, suggesting moderate diagnostic agreement. Using the clerical coder's results, the mean recommended LOS for all cases of cerebrovascular disease over the study period was calculated at 6.68 days. The corresponding values for the two medical coders were 6.68 days and 6.75 days. CONCLUSIONS: Diagnostic agreement between clinicians was moderate. Consideration of alternative diagnostic possibilities and the difficulty in determining the duration of neurological deficit were the main reasons for diagnostic disagreement. The mean recommended LOS was similar, however, when comparing results from all three observers.

Adult↗
PubMed2004

Diagnostic radiography in pregnancy: risks and reality.

BACKGROUND: The use of X-rays, computed tomography scanning and nuclear medicine imaging in the pregnant woman is a source of great anxiety for the patient, her family and the treating doctor. METHODS: A literature review of appropriate databases, articles and relevant institutional protocols was performed. Data was sought regarding any adverse effects of diagnostic radiation in pregnancy, fetal absorbed dose of diagnostic radiation and how the timing of exposure and form of administration might influence these effects. RESULTS: The estimated radiation dose for a fetus from background sources as well as medical imaging was identified. Most diagnostic radiation procedures will lead to a fetal absorbed dose of less than 1 mGy for imaging beyond the abdomen/pelvis and less than 10 mGy for direct or nuclear medicine imaging. Potential adverse outcomes related to radiation exposure during pregnancy include teratogenicity, genetic damage, intrauterine death and increased risk of malignancy. The only adverse effect statistically proven at the dose levels associated with diagnostic radiation procedures is a very small increase in childhood malignancy, with an estimated increase of one additional cancer death per 1700 10 mGy exposures. The important exception was the risk to the fetal thyroid from radioiodine exposure after 12 weeks' gestation. CONCLUSION: In practice, diagnostic radiography during pregnancy not involving direct abdominal/pelvic high dosage, is not associated with any significant adverse events. Counselling of pregnant women who require diagnostic radiographic procedures as well as those inadvertently exposed should be based on the available human data with an emphasis on the minimal impact of such procedures.

Female↗
PubMed1998

When should induction protocols be used in the diagnostic evaluation of patients with paroxysmal events?

PURPOSE: To determine the timing of spontaneous psychogenic nonepileptic events (PNEE) during video-EEG telemetry (VEEG), and the need to use induction protocols (IP). METHODS: We studied 100 consecutive patients (75 females, 25 males) admitted to our inpatient VEEG unit from July 1994 to June 1996 for differential diagnosis of paroxysmal events. We recorded the time to the first diagnostic spontaneous event, identified by the patient or a family member as typical. Episodes were classified as PNEE, physiologic nonepileptic events (PhysNEE), and epileptic seizures (ES). RESULTS: The mean duration of VEEG was 74+/-SD 54.1 h. In 82 patients, a diagnostic event occurred spontaneously. The first event was an ES in 22 patients, a PNEE in 53, and a PhysNEE in 7. The time to first diagnostic event was significantly shorter for PNEE than for ES [15.0+/-SD 16.3 h (range 5 min to 58 h) vs. 28.6+/-SD 34.0 h (range 1-110 h) F=15.621, p < 0.0001]. In the first 24 h, 77.4% of the patients with PNEE had an event. By 48 h, all but 2 (96.2%) had had diagnostic events. After the first 58 h of monitoring, all patients with PNEE experienced a spontaneous diagnostic event. CONCLUSION: Spontaneous events can be expected to occur within 48 h in most patients with PNEE. Therefore, if IP are to be used as a diagnostic tool, we suggest that they be withheld during the initial 48 h of VEEG monitoring.

Adolescent↗
PubMed1988

Computerized history and self-assessment questionnaire for diagnostic screening among patients with dementia.

In order to standardize and quantify diagnostic information derived from medical histories and case reports given by demented patients, their families or care-providers, a questionnaire has been developed containing 94 questions. The output is categorized by computer into graphic clinical scales which correlate and weigh information relating to seven of the most common causes of dementia. The present investigation assesses the validity of predictive diagnostic classifications derived from the clinical scales tested on admission by correlating them later with final diagnoses determined independently by thorough clinical evaluation including standard diagnostic tests, computed tomography and nuclear magnetic resonance scans. Results of 101 healthy, neurologically normal, age-matched volunteers and 140 patients representative of the more common forms of dementia indicate that correct diagnostic identification was: 75% for dementia secondary to Parkinson's disease, 100% for Huntington's disease, 90.2% for Alzheimer's disease, 82.4% for multi-infarct dementia, 90.0% for posttraumatic dementia, 77.8% for normal-pressure hydrocephalus and 85.7% for Wernicke-Korsakoff dementia. Correct diagnostic assignment was highly significant (P less than .0005). The screening questionnaire may prove to be a useful and standard diagnostic tool for clinicians and investigators concerned with epidemiology, prevention and treatment of dementia.

Adult↗
PubMed1986

Advances in single-chamber pacemaker diagnostic data.

Diagnostic data, which is Holter-type information documenting the pulse generators' interaction with the patient over time, are now available in single chamber pulse generators from at least six manufacturers. Diagnostic data are available in bradycardia, tachycardia, and rate-responsive pulse generators. Six hypothetical examples discuss the clinical utility of advanced diagnostic data. Three examples examine the use of diagnostic data with bradycardia pulse generators. These use rate histograms or high-rate counters to solve programming and patient problems. Two examples involve antitachycardia pulse generators and the uses for diagnostic data in both chronic and acute cases. One example deals with the use of maximum and minimum temperature diagnostics in proper programming of a temperature rate-responsive device.

Arrhythmias, Cardiac↗
PubMed1990

Statistical methods for comparing dental diagnostic procedures.

In dental diagnosis, there are typically two or more clinical diagnostic procedures which may be used either independently or jointly to reach a conclusion regarding the presence of a particular disease in a patient. To determine which of these diagnostic procedures are more accurate, statistical methods may be applied to research data in which the true health status as well as the diagnosis provided by each clinical procedure are available on each observation. Results arising from this type of analysis can be of great interest to clinicians when the diagnostic procedures themselves are costly, painful, or even potentially harmful to the patient. Considered here is the special situation encountered in dental research in which each patient can have multiple concurrent cases of a certain disease such as caries, for then the statistical evaluation of diagnostic procedures is even further complicated. This report describes several statistical approaches for comparing the efficacy of diagnostic tests and illustrates their application on data from a study of diagnostic radiographs for dental caries.

Adult↗
PubMed1993

Assessment of diagnostic accuracy in caries detection: an analysis of two methods.

The quality of a diagnostic tool for caries detection is usually evaluated by quantification of observer performance using sensitivity and specificity values calculated from data obtained from ordinal caries depth rating scales. The application of Receiver Operating Characteristic (ROC) analysis has been restricted to the use of confidence rating scales. The aim of this investigation was to study the appropriateness of ROC analysis using caries depth ratings by comparing sensitivity and specificity values to parameters of diagnostic performance obtained by ROC analysis. In two recent reports, sensitivity and specificity values were utilized to express diagnostic accuracy of observer performance from specified caries diagnostic systems. The raw data from these investigations were subjected to ROC analysis in the current study. The results illustrated that ROC analysis, producing estimates of sensitivities for all specificities, yielded more comprehensive measures of diagnostic performance than single values for sensitivity and specificity. In particular, the area under the ROC curve constituted a clearly interpretable parameter representing the quality of diagnostic performance.

Analysis of Variance↗
PubMed1997

Diagnostic tools and measurements--impact on appropriate care.

The diagnosis of primary coronal caries should be seen as a complex process, comprising both detection and measurement phases, which enables clinicians, researchers and epidemiologists to make informed decisions about the management and prognosis of the disease process. The different diagnostic thresholds employed for measurements of caries experience can be viewed as an iceberg, a metaphor which demonstrates the ambiguity of the term "caries free" and which can also represent the differing management options appropriate for the care of different types of active and inactive lesions: NAC (No Active Care). PCA (Preventive Care Advised) and OCA (Operative Care Advised). There are considerable methodological difficulties in drawing valid comparisons between studies using incompatible criteria and simulations. However, it is apparent that no caries diagnostic tool in current clinical use fulfils all of the ideal criteria for measurements needed to plan and monitor appropriate care. Systems providing reliable serial measurements with which to assess future caries risk and present caries activity are urgently required as diagnostic tasks are becoming both more difficult and more important from the standpoint of long-term oral health. Existing diagnostic tools frequently rely on subjective judgements and provide only semi-quantitative measures insensitive to smaller lesions. In the future tools are needed which are objective, quantitative and which can provide acceptable compromises between sensitivity and specificity for a wide range of applications for individual patient care as well as for research and survey use. Key problem areas with existing tools include confusion in terminology and between caries assessments made by clinicians and epidemiologists as well as the lack of valid measurements relating to the activity of primary root caries and secondary caries. Deficiencies with current tools impact on the care of individuals by allowing false negative diagnoses of hidden occlusal dentine lesions and approximal cavities on the one hand, whilst generating some false positive diagnoses on sound surfaces leading to inappropriate decisions to restore on the other. At the population level, current conventional tools significantly underestimate overall caries experience. In future the adoption of more accurate and reliable methods would facilitate more effective preventive care and promote more appropriate restorative treatment decisions. Research in this area should focus for the next five years on diagnostic technologies which: 1) inform valid prospective caries risk assessments for different age groups, 2) can help to determine present caries activity and monitor lesion behaviour over time and 3) help identify methods which can implement existing and new research knowledge about diagnostic tools into clinical and research practice.

Age Factors↗
PubMed1999

Diagnostic benefit of echocontrast enhancement for the insufficient transtemporal bone window.

Echocontrast agents (ECA) are known to improve transcranial color-coded duplex (TCCD) imaging, but its diagnostic benefit in the routine clinical setting has not clearly been defined. The authors investigated the diagnostic benefit of ECA application in 54 patients with insufficient transtemporal bone window, consecutively referred to their ultrasound laboratory. According to the precontrast imaging quality, patients were assigned to three categories: A, no intracranial structures or vessel segments visible on B-mode imaging and TCCD (n = 5); and intracranial structures visible on B-mode imaging and vessel segments less than 5 mm in length (B, n = 21), or larger than 5 mm in length (C, n = 28) visible on TCCD. The effect of the echocontrast enhancement was assessed with respect to signal enhancement, imaging quality, and diagnostic confidence. In 49 out of 54 patients (91%), a significant improvement of the imaging quality was noted, enabling 43 (80%) neurovascular diagnoses of sufficient diagnostic confidence. The diagnostic ECA effect was strongly dependent on the precontrast imaging quality: upon echoenhancement, a satisfactory image quality was obtained in none of the patients of category A, as opposed to 16 (76%) and 27 (96%) patients of categories B and C, respectively. In summary, in 80% of our consecutive patient series with insufficient transtemporal bone window, application of ECA allowed for a conclusive TCCD study. Properties of the transtemporal precontrast scans are strongly predictive of the diagnostic benefit and should be taken into the decisive consideration.

Adult↗