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PubMed2001

Improving diagnostic yield in brain biopsy: coupling spectroscopic targeting with real-time needle placement.

The purpose of this study was to determine the utility of intraoperative magnetic resonance spectroscopy (MRS) for targeting during brain biopsy using a skull-mounted trajectory guide. From January 1999 to January 2001, 17 patients had intraoperative MRS-guided brain biopsy using a trajectory guide. Ten had turbo spectroscopic imaging (TSI), and seven had both SVS (single-voxel spectroscopy) and TSI. Prospective stereotaxy was used to align the device in a short-bore 1.5-T MR scanner. Areas of elevated choline relative to creatine on SVS and TSI were targeted during the biopsy. Intraoperative imaging confirmed appropriate positioning of the biopsy needle at the time of tissue sampling in all cases. All 17 biopsies (100%) yielded diagnostic tissue. Six patients (34%) had glioblastomas multiforme, three (18%) had anaplastic astrocytomas, three (18%) had anaplastic oligodendrogliomas, two (12%) had radiation necrosis, and one each (6%) had germinoma, ganglioglioma, and astrocytoma. Postoperative imaging confirmed the absence of clinically and radiographically relevant hemorrhage. The findings on SVS correlated with the pathology in all seven cases (100%). In 13 of 17 patients (76%) who had TSI, the spectra correlated well with the permanent pathologic examination. The SVS and TSI spectra were similar in six of seven (86%) cases. Intraoperative MRS-guided brain biopsy using a trajectory guide is a simple, safe, and accurate technique for accessing areas of the brain of diagnostic interest. J. Magn. Reson. Imaging 2001;13:12-15.

Biopsy, Needle↗

PubMedDate not supplied

Diagnostic yield of gastroscopy in a general surgical unit.

Gastroscopy is the gold standard for investigating upper gastrointestinal complaints. Open access gastroscopy has advantages, but may not always be feasible in a small unit. Our 2-consultant general surgical unit provides gastroscopy on demand for medical and surgical patients. We audited the 499 gastroscopies carried out in our unit in 1997 to assess yield and diagnostic trends. The overall diagnostic yield of 69 per cent was comparable with published data from centres in Ireland and overseas. Diagnostic yield in our series was significantly lower for medical patients (59 per cent) than for surgical patients (72 per cent) (p < 0.05). Yield also varied considerably according to indication for referral. Patients referred with anaemia had a low yield (41 per cent). The indications associated with high yields were haematemesis (95 per cent), dysphagia (91 per cent), and persistent vomiting (85 per cent).

Adolescent↗

PubMed2000

Diagnostic yield of bronchoscopic sampling methods in bronchial carcinoma.

OBJECTIVES: The aim was to study the yield of malignant or suspicious cells from bronchoalveolar lavage (BAL), endobronchial biopsy (BX) and endobronchial brushing (BR) specimens obtained at bronchoscopy. METHODOLOGY: We prospectively followed up all patients who had undergone bronchoscopy and studied those with subsequent diagnosis of bronchial carcinoma at a tertiary referral centre. Bronchoalveolar lavage, BX and BR were performed, sequentially whenever possible, by one pulmonologist. The parameters assessed were age, gender, macroscopic bronchoscopic findings, TNM staging, radiological findings, histological typing, and diagnostic yield from BAL, BX, and BR. RESULTS: One hundred patients (31 females, 69 males; mean age +/- SD, 61.8+/-12.7 years; range 32-81 years) were studied between 1995 and 1997. Of these, BAL, BX and BR were performed on 100, 64 and 37 cases which yielded diagnostic specimens for bronchial carcinoma in 69, 78.1, and 62.2% of cases, respectively (P > 0.05). Diagnostic specimens were therefore obtained in 69,50, and 23% of the entire patient cohort from BAL, BX, and BR, respectively (P < 0.001). The diagnostic yield of BAL was independent of patient age, gender, site of lesion, TNM staging, histological typing and macroscopic bronchoscopic findings. Addition of BX, BR and postbronchoscopic sputum sampling to BAL only increased the yield of diagnostic specimens for bronchial carcinoma by 7, 0, and 4%, respectively. CONCLUSION: Bronchoalveolar lavage is a highly effective sampling method to obtain cytological evidence for bronchial carcinoma. The diagnostic yield for BAL is independent of tumour or other clinical characteristics. Further studies should be performed to confirm these important and clinically relevant findings.

Adult↗

PubMed1992

Cytology of transitional-cell carcinoma of the urinary bladder: diagnostic yield and histologic basis.

The diagnostic yield of cytology in histologically proven transitional-cell carcinoma (TCC) of the urinary bladder has been studied in 100 cases. Cytohistologic correlation rates were 20 percent, 61.7 percent, and 92.8 percent, respectively, for grade 1, 2, and 3 tumors. When further evaluated, G2 cases were segregated into 2 subcategories, G2a and G2b, based on histologic preservation of nuclear polarity, pleomorphism, and other cellular irregularities. Correlation rates were rather low for G2a cases (6/18, 33%) and high for G2b cases, (23/29; 79%). The prevalence of atypical cells was 2 (11.1%) cases in G2a and 16 (55.2%) cases in G2b. The results of this study confirm that cytology has an extremely varying diagnostic yield in urinary bladder TCC. Greater cell exfoliation, increased atypia, and a tendency to infiltration of G2b and G3 cases probably account for the higher diagnostic yield detected in these groups.

Carcinoma, Transitional Cell↗

PubMed2026

Whole-Exome Sequencing in a Consanguinity-Enriched South Indian Retinitis Pigmentosa Cohort: Diagnostic Yield and Molecular Spectrum.

PURPOSE: To determine the molecular diagnostic yield, variant spectrum, inheritance architecture, and influence of consanguinity on whole-exome sequencing outcomes in a South Indian retinitis pigmentosa (RP) cohort. DESIGN: Prospective, registry-based cohort study. SUBJECTS: A total of 113 affected participants were enrolled through the Aravind Registry for Inherited Diseases of the Eye, including 109 unrelated probands and 4 affected relatives from already represented families. Primary analyses were restricted to the 109 unrelated probands. METHODS: Whole-exome sequencing was performed using a clinical exome workflow. Variants were interpreted using American College of Medical Genetics and Genomics/Association for Molecular Pathology criteria and cases were categorized as solved, possibly solved, inconclusive, or unsolved using prespecified inheritance-aware rules. MAIN OUTCOME MEASURES: Molecular diagnostic yield, distribution of implicated genes and variant classes, inheritance architecture, and diagnostic yield stratified by consanguinity status. RESULTS: Among the 109 unrelated probands, mean age at testing was 39.3 ± 14.1 years and 58.7% were male. Whole-exome sequencing identified 186 distinct rare variants across 92 inherited retinal disease genes, including 26 pathogenic and 33 likely pathogenic variants. A molecular diagnosis was established in 50 of 109 probands (45.9%), including 42 solved and 8 possibly solved cases; 45 (41.3%) were inconclusive and 14 (12.8%) remained unsolved, including 4 (3.7%) in whom no candidate variant was identified. EYS, USH2A, and ADGRV1 were the most frequently implicated genes. Autosomal recessive (AR) disease predominated (44/50, 88.0%). Consanguineous AR cases were exclusively homozygous (17/17); notably, 68.0% of nonconsanguineous AR cases were also homozygous (P = 0.013). Diagnostic yield was higher in consanguineous probands (51.4% vs. 41.7%), without reaching significance. Recurrent alleles included an established South Asian founder variant (MFSD8 c.1361T>C) and candidate founder alleles in EYS (c.4321C>T) and ADGRV1 (c.14329C>T). CONCLUSIONS: Whole-exome sequencing established a molecular diagnosis in nearly half of this South Indian RP cohort and revealed a predominantly recessive, homozygosity-enriched architecture shaped by consanguinity. These findings define a region-specific variant landscape to support clinical interpretation, genetic counseling, and future trial enrollment in this underrepresented population. FINANCIAL DISCLOSURES: The authors have no proprietary or commercial interest in any materials discussed in this article.

Consanguinity↗

PubMed2002

Screening panoramic radiography of new adult patients: diagnostic yield when combined with bitewing radiography and identification of selection criteria.

OBJECTIVES: To measure the radiological diagnostic yield on screening panoramic radiographs taken of new adult patients and to identify selection criteria for panoramic radiography of new adult patients. DESIGN: Survey of 1,817 consecutive panoramic radiographs taken as 'routine' on new patients with statistical analysis of clinical and radiological findings. SETTING: All radiographs were obtained from 41 general dental practitioners (GDPs). The GDPs provided the clinical information about the patient obtained by history and examination. Collection of material occurred in 1998/1999. MATERIALS AND METHODS: Two dental radiologists recorded the radiological findings on each of 1,817 panoramic radiographs by consensus. Those findings that would have been identified from bilateral posterior bitewing radiographs of each patient were then excluded to give modified figures for radiological findings. MAIN OUTCOME MEASURES: Indices of diagnostic yield were devised and calculated for each radiograph from the data on radiological findings. Total diagnostic yield (DY) and modified diagnostic yield (MDY), after exclusion of findings identifiable on bitewing radiographs, were both calculated. Clinical indicators of a high MDY were identified using stepwise multiple regression analysis. RESULTS: MDY was 0 for 17% of the radiographs (all patients) and 23% of the radiographs when the asymptomatic group were considered. The clinical variables for which the significance was high (p < 0.001) were: increasing number of teeth with clinical suspicion of periapical pathology, presence of partially erupted teeth, increasing number of clinically evident carious lesions, partially dentate status and presence of crowns. CONCLUSION: Taking posterior bitewing radiographs of new adult patients would reduce the diagnostic yield identified solely by panoramic radiography. Using clinical factors derived from the history and examination as radiographic selection criteria modestly improves the odds of achieving a high diagnostic yield from panoramic radiography.

Adult↗

PubMed1998

[Factors related to diagnostic yield and complications of transbronchial biopsy].

To study the diagnostic yield of transbronchial biopsy (TBB) in lung diseases of different ethiology, as well as to examine several factors implicated in diagnostic yield and complications of TBB. Retrospective study of a series of 172 patients (98 women and 74 men) undergoing TBB. Clinical variables, x-ray and CT patterns and technical factors related to TBB were analyzed in relation to diagnostic yield and definitive diagnosis. We recorded the main complications and studied the possible mechanisms implicated in their appearance. The results of TBB were classified as follows: 1) diagnostic TBB (42.8%); 2) nonspecific TBB (21.1%); absence of parenchyma (NP) (9.7%); 4) normal parenchyma (23.4%); 5) incorrect diagnosis (2.9%). Overall yield was 43.6% but rose to 52% when NP and no infiltrative pneumopathies were excluded. The main findings were infections (23.4%), neoplasms (19.4%), sarcoidosis (14.2%), idiopathic pulmonary fibrosis (IPF) (17.7%); and other (23.4%). Significant differences in diagnosis were found for age, sex, time of evolution prior to TBB, and x-ray and CT patterns. Complications and pneumothorax appeared more frequently in IPF, neoplasms and infections, although the differences were non significant. Diagnostic value depended mainly on type of disease and ranged from 60% for sarcoidosis to 24% for IPF (p < 0.05), with no differences related to age, sex, presence of immunosuppression, number of TBB or tolerance to exploration. Yield was higher, however, for patients with no loss of radiographic pulmonary volume (56.3% versus 37.5%) and with absence of a CT reticular pattern (44.7% versus 27.3%). Type of opacites also influenced yield (53.4% for ground glass versus 26.7% for reticular patterns), as did distribution of lesions (8.4% for peripheral patterns versus 48.3% for diffuse patterns and 50% for peribronchio-vascular patterns). The site of TBB was the only factor showing clearly significant differences in yield (100% in mild lobe versus 29.5% in upper lobes). Tolerance was poorer in older patients (63.5 +/- 10 versus 52.2 +/- 17 years) and with greater function abnormalities (%FEV1: 48.2 +/- 16.8 versus 70.2 +/- 17.1). Poor tolerance of exploration was associated with the appearance of complications (16.6% vs 6.3) and pneumothorax (25% versus 6.8%). The diagnostic yield of TBB was mainly influenced by the type of disease studied. The various imaging techniques were fundamental for establishing preliminary diagnoses and degree of evolution of a specific cases. In our series, tolerance of the technique was a reliable predictor of complications and the presence of post-biops pneumothorax.

Adult↗

PubMed2002

Routine panoramic radiography of new adult patients in general dental practice: relevance of diagnostic yield to treatment and identification of radiographic selection criteria.

OBJECTIVES: We sought to measure the diagnostic yield of relevance to treatment on routine panoramic radiographs taken of new adult (ie, 18 years and over) patients in general dental practice. STUDY DESIGN: Routine panoramic radiographs (n = 1817) obtained from general dental practice were assessed and radiologic yield recorded using consensus viewing by 2 dental radiologists. A modified diagnostic yield of relevance to treatment for each radiograph was calculated by omission of findings that would have been identified on bilateral posterior bitewing radiographs and of radiologic findings of no relevance to treatment. Stepwise logistic regression analysis was used in attempt to identify clinical indicators of a high diagnostic yield of relevance to treatment. RESULTS: The diagnostic yield of relevance to treatment was zero for the majority (56%) of patients. This figure rose to 71% when the symptom-free patients were considered. Five clinical indicators for panoramic radiography were identified, as follows: clinical suspicion of teeth with periapical pathologic conditions, presence of partially erupted teeth, clinically evident caries lesions, swelling, and clinically suspected unerupted teeth. CONCLUSION: Routine panoramic radiography of adult dental patients is not supported by the results of this study. The use of clinical indicators to select patients may help to improve diagnostic yield.

Adult↗

PubMed1986

Bethanechol increases the diagnostic yield in patients with esophageal chest pain.

The diagnostic yield of routine esophageal manometrics in evaluating noncardiac chest pain is low. To determine if bethanechol stimulation would increase the diagnostic yield, we examined 87 patients with chest pain but no gastroesophageal reflux, 47 patients with gastroesophageal reflux but no chest pain, and 20 normal subjects. All subjects underwent standard esophageal manometrics before and after two doses of 50 micrograms/kg body wt bethanechol administered subcutaneously 15 min apart. Mean amplitude and duration of contractions and percentage of abnormal contractions were measured in the distal 7 cm of the esophageal body. Pathologic manometric parameters were defined as mean +/- 2 SD of values obtained in normal patients. Patients with chest pain had pathological responses for amplitude of contraction, duration of contraction, and percentage of abnormal contractions of 31%, 14%, and 22%, respectively, in the basal period. This increased to 43%, 66%, and 40%, respectively, after the first dose of bethanechol and to 53%, 85%, and 82% after the second dose of bethanechol. Chest pain was reproduced with new manometric abnormalities in 46% of patients after the first dose of bethanechol and in 77% after the second dose. Our conclusions are that: sequential bethanechol administration significantly increases the diagnostic yield of standard esophageal manometrics in the evaluation of noncardiac chest pain and duration of contraction after pharmacologic provocation with bethanechol is the best parameter to segregate patients with chest pain from normal subjects and gastroesophageal reflux patients.

Adult↗

PubMed2002

Diagnostic yield of vitrectomy in eyes with suspected posterior segment infection or malignancy.

PURPOSE: To determine the yield of diagnostic pars plana vitrectomy in eyes with suspected posterior segment inflammation or malignancy when clinical examination and systemic laboratory testing did not yield a specific diagnosis. DESIGN: Non-comparative interventional case series PARTICIPANTS: Eighty-seven consecutive patients (90 eyes) who underwent diagnostic pars plana vitrectomy from 1989 through 1999. INTERVENTIONS: Vitreous samples were analyzed in a directed manner based on the preoperative clinical examination and systemic laboratory testing. MAIN OUTCOME MEASURES: Diagnosis from each test performed on the vitreous samples. RESULTS: Diagnostic vitrectomy was performed alone in 6 eyes (7%) and as part of a therapeutic procedure in the remaining 84 eyes. The diagnostic tests performed most frequently included cytopathology (83%), microbiologic culture and sensitivity (43%), polymerase chain reaction (PCR) (36%), and intraocular antibody levels for T. canis (14%). Of these, intraocular antibody testing and PCR had the highest positive yield, 46% and 39%, respectively. Overall, directed vitreous analysis identified a specific cause in 35 eyes (39%). Of the 65 cases in which an underlying infection was suspected preoperatively, the procedure yielded a specific diagnosis in 27 (42%). When intraocular malignancy was considered preoperatively (71 eyes), a diagnosis of intraocular lymphoma was obtained in seven (10%). This difference between these diagnostic yields was significant (P = 0.02, Fisher's exact test). CONCLUSIONS: Diagnostic vitrectomy with directed vitreous fluid analysis yields a specific cause and guides subsequent therapy in a high percentage of cases. This procedure is a valuable adjunct in cases that cannot be diagnosed by less invasive methods.

Adolescent↗

PubMed2002

Open lung biopsy in bone marrow transplant recipients has a poor diagnostic yield for a specific diagnosis.

The diagnostic yield of open lung biopsy (OLB) in bone marrow transplantation (BMT) recipients having pulmonary infiltrates has not been evaluated recently. Therefore, we reviewed our 2-year experience (1998-99) with such patients at The University of Texas M. D. Anderson Cancer Center. We found 12 BMT recipients who underwent OLB analysis for the evaluation of pulmonary infiltrates. A treatable infectious etiology leading to the initiation or modification of antimicrobial agent administration was found in only two patients having bilateral nodular disease and one having bilateral parenchymal infiltrates. We conclude that OLB in BMT patients having diffuse pulmonary infiltrates has a low diagnostic yield for treatable infectious etiologies.

Adolescent↗

PubMed1998

Cytology of bronchial biopsy rinse fluid to improve the diagnostic yield for lung cancer.

Sampling techniques are combined during bronchoscopy to increase the diagnostic yield for endobronchial malignant tumours. Bronchial biopsy provides the definitive histological diagnosis in most cases, but accompanying cytological procedures such as washing, brushing, needle aspiration or imprint cytology can increase diagnostic yield. In this prospective study, a different cytological technique, that could enhance the diagnostic yield of bronchoscopy without increasing its time or cost, was tested. Flexible bronchoscopy was performed in 93 patients suspected of having pulmonary neoplasms. Bronchial biopsies were initially placed in a balanced salt solution. When bronchoscopy was finished, all visible tissue fragments were removed and placed in formalin to undergo histopathological examination and the rinse fluid was sent for cytological examination. Washing was performed routinely but no cytological brushing was employed. Eighty-two patients had final diagnoses of malignant neoplasm. In four (4.8%) of these patients, the only positive result came from the cytological examination of the bronchial biopsy rinse fluid. No false-positive results were found. The agreement with the histological results was 81.8%. The addition of bronchial biopsy rinse-fluid examination increased the sensitivity of bronchoscopy from 65.8% to 70.7% (McNemar's p=0.009). The cytological study of bronchial biopsy rinse fluid offers reliable positive results in an additional 4.8% of cases, thus enhancing bronchoscopic diagnostic yield for malignant endobronchial tumours while neither prolonging the procedure nor increasing costs.

Biopsy, Needle↗

PubMed1997

Diagnostic yield of brain biopsy in neurodegenerative disorders.

OBJECTIVE: The diagnostic yield and therapeutic implications of brain biopsy were determined in a series of 50 consecutive brain biopsies that were performed in 48 patients between 1990 and 1995 at The Johns Hopkins Hospital to assess progressive neurodegenerative disorders of unclear origin. METHODS: Severely immunocompromised patients and patients undergoing biopsies for suspected neoplastic lesions were excluded from this analysis. Before surgery, the patients had undergone extensive laboratory and radiographic tests, including lumbar puncture (all 48 patients), electroencephalography (26 of 48 patients), magnetic resonance imaging (all 48 patients), and angiography (17 of 48 patients). Despite the results of these studies, diagnoses could not be established, and thus, brain biopsies were undertaken. RESULTS: Only 10 of the 50 biopsies (44 open procedures and 6 stereotactic procedures) led to diagnoses, resulting in a diagnostic yield of 20%. An additional three biopsies (6%) were only suggestive of diagnoses. The results of 33 biopsies (66%) were abnormal but nonspecific, and the results of 4 (8%) were normal. Minor complications associated with biopsy occurred in five cases (10%), and there were no deaths. Of the 10 patients whose biopsies were diagnostic, only 4 underwent meaningful therapeutic intervention as a result of the procedure, resulting in an overall therapeutic benefit in only 8% of all the cases. An analysis of patient subgroups to elucidate a correlation with diagnostic biopsy revealed that patients with focal magnetic resonance imaging findings had the highest likelihood of a diagnostic biopsy (odds ratio, 4.00). Electroencephalography and laboratory abnormalities were not predictive of a diagnostic biopsy. CONCLUSION: We conclude that the current diagnostic yield (20%) of brain biopsy for progressive neurodegenerative disorders is lower than that of earlier reports and that the therapeutic benefits of the procedure are limited.

Adolescent↗

PubMed2025

A meta-analysis of diagnostic yield and clinical utility of genome and exome sequencing in pediatric rare and undiagnosed genetic diseases.

PURPOSE: To systematically evaluate the diagnostic yield and clinical utility of genome sequencing (GS) and exome sequencing (ES; genome-wide sequencing [GWS]) in pediatric patients with rare and undiagnosed genetic diseases. METHODS: We conducted a meta-analysis of studies published between 2011 and 2023. To address study heterogeneity, comparative analyses included within-cohort studies using random-effects models. RESULTS: We identified 108 studies including 24,631 probands with diverse clinical indications. The pooled diagnostic yield among within-cohort studies (N = 13) for GWS was 34.2% (95% CI: 27.6-41.5; I2: 86%) vs 18.1% (95% CI: 13.1-24.6; I2: 89%) for non-GWS, with 2.4-times odds of diagnosis (95% CI: 1.40-4.04; P < .05). The pooled diagnostic yield among within-cohort studies (N = 3) for GS was 30.6% (95% CI: 18.6-45.9; I2: 79%) vs 23.2% (95% CI: 18.5-28.7; I2: 58%) for ES, with 1.7-times the odds of diagnosis (95% CI: 0.94-2.92; P = .13). In first-line testing, the diagnostic yield tended to be higher for GS than for ES across clinical subgroups. The pooled clinical utility among patients with a positive diagnosis was 58.7% (95% CI: 47.3-69.2; I2: 81%) for GS and 54.5% (95% CI: 40.7-67.6; I2: 87%) for ES. CONCLUSION: GS appears to have a higher diagnostic yield than ES, with similar clinical utility per positive diagnosis.

Child↗

PubMed1997

Empiric treatments impair the diagnostic yield of BAL in HIV-positive patients.

OBJECTIVE: To investigate the influence of empiric treatments prior to fiberoptic bronchoscopy (FOB) on the diagnostic yield of BAL in HIV-positive patients with respiratory symptoms. METHOD: We studied 123 consecutive FOBs with BAL in HIV-positive patients; 101 of these patients (82%) had received previous antimicrobial treatment from 1 to 60 days. Diagnostic yield of BAL for Pneumocystis carinii, Mycobacterium tuberculosis, and bacterial pneumonia was compared between patients with and without previous empiric treatments. RESULTS: A diagnosis was obtained in 85 patients (69%), of whom 17 (20%) had multiple infections. Diagnostic yield was higher in patients without previous treatment, 91% (20/22) compared with 64% (65/101), p < 0.03. Diagnostic yield was also higher for bacterial pneumonia: seven isolations from 22 patients not receiving previous empiric treatment (32%), compared with 11 of those who had (11%; p < 0.02). The duration of empiric treatment against P carinii in patients in whom it was isolated was significantly shorter than in those in whom P carinii was not detected (3.5 +/- 1.8 days compared with 5.2 +/- 2.4 days; p = 0.003). FOB permitted a change in treatment in 62% of patients with a final diagnosis. CONCLUSION: This study demonstrates that empiric treatments prior to FOB significantly impair the diagnostic yield of BAL in detecting common pathogens in HIV-infected patients with respiratory symptoms.

AIDS-Related Opportunistic Infections↗

PubMed1994

The diagnostic yield of intravenous urography: a demographic study.

OBJECTIVE: To examine the impact of intravenous urography (IVU) on patient management in unselected patients in an effort to identify groups in which the use of urography could be reduced. PATIENTS AND METHODS: The results of IVU in 235 consecutive unselected patients were assessed prospectively to establish the value of IVU in patient management. Patients were divided into subgroups on the basis of age, sex, presenting symptoms and source of referral. The percentage of examinations with findings affecting patient management was taken as the 'positive diagnostic yield.' Differences between the positive diagnostic yields of IVU in the various groups were examined using the chi 2 test. RESULTS: For all patients the diagnostic yield was 37.4%. In patients over 50 years of age the yield was 46% while below that age the yield fell to 20%. This difference was significant (chi 2 = 13.88, P < 0.001). There were no significant differences between the other defined groups. Specifically, patients referred by general practitioners were as likely to have an IVU abnormality as were patients referred by a hospital practitioner. Patients with painless microscopic haematuria had a lower diagnostic yield (20%) than the other groups examined but this was not significant. CONCLUSION: IVU has a high diagnostic yield in an unselected population. Although the yield is lower in younger patients IVU offers advantages over other techniques in the investigation of urolithiasis--the commonest positive diagnosis in this study. We argue that it should retain its position as the primary investigation for the majority of patients with urological disease, particularly those suffering loin pain or haematuria.

Adolescent↗

PubMedDate not supplied

Diagnostic yield of MR-guided liver biopsies compared with CT- and US-guided liver biopsies.

PURPOSE: To compare diagnostic yield and complication rates of magnetic resonance (MR)-guided versus computed tomography (CT)- and ultrasound (US)-guided liver biopsies. MATERIALS AND METHODS: MR-, CT-, and US-guided liver biopsies performed between 9/96 and 9/98 were compared. Sixty patients (21 men and 39 women, mean age 60 years) underwent MR-guided biopsy of liver lesions. Thirty patients (16 men and 14 women, mean age 59 years) underwent CT-guided biopsy. Eighteen patients (seven men and 11 women, mean age 50 years) underwent US-guided biopsy. MR procedures were performed in an open-configuration 0.5-T Signa SP MR unit. Lesion localization used standard T1 and T2 sequences, whereas biopsies were performed with multiplanar spoiled gradient recalled echo and fast gradient recalled echo sequences. A coaxial system with an MR-compatible 18-gauge stabilizing needle and a 21-gauge aspiration needle was used to obtain all samples. In CT and US procedures, a 19-gauge stabilizing needle and a 21-gauge aspiration or a 20-gauge core biopsy needle were used. A cytotechnologist was present to determine the adequacy of samples. RESULTS: MR had a diagnostic yield of 61%. CT and US had diagnostic yields of 67% and 61%, respectively. No serious complications were reported for MR and US procedures. Two CT biopsies resulted in postprocedural hemorrhage. One patient required surgical exploration and died. CONCLUSIONS: MR-guided biopsy of liver lesions with use of a 0.5-T open-configuration magnet is safe and accurate when compared with CT and US. No statistical difference was observed between the diagnostic yield of biopsies performed with MR, CT, and US guidance. MR enabled biopsy of a number of lesions in the hepatic dome and lesions with low contrast, which would normally be difficult to sample safely with use of CT or US.

Biopsy, Needle↗

PubMed1998

Stereotactic biopsy of intracranial brain lesions. High diagnostic yield without increased complications: 65 consecutive biopsies with early postoperative CT scans.

Diagnostic yield and complication rate were analyzed for a series of 65 consecutive stereotactic biopsies of intra-axial brain lesions. The diagnostic yield was 98.5 +/- 1.5% and the complication rate was 1.5%. A median number of 14 biopsies (range 1-48) were taken per lesion. The biopsy sites followed a clockwise pattern, going from the superficial margin to the center and the deep margin of the lesion with respect to the inner table of the skull. A side window cannula biopsy needle was used. All patients underwent immediate postoperative CT scans within 4 h of biopsy to rule out intracranial complications. All patients were discharged within 24 h after biopsy, unless medical reasons unrelated to the biopsy required further hospitalization. We attribute the high diagnostic yield in our series to the high number of systematically taken biopsies per lesion. The higher number of biopsies did not lead to an increase in complications. From our experience, it appears safe to discharge patients the same day or within 24 h after a stereotactic biopsy if the postoperative CT shows no complication. Stereotactic biopsy could often safely be performed on an outpatient basis.

Adolescent↗