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H Hricak

Publications and source records attributed to H Hricak.

At least 37 records · Page 2Linked to original sources
PubMed2000

The prostate: MR imaging and spectroscopy. Present and future.

The applications of combined MR imaging and MR spectroscopic imaging of prostate cancer have expanded significantly over the past 10 years and have reached the point of clinical trial results to test robustness and clinical significance. MR spectroscopic imaging extends the diagnostic evaluation of prostate cancer beyond the morphologic information provided by MR imaging throughout the detection of cellular metabolites. The combined metabolic and anatomic information provided by MR imaging and MR spectroscopic imaging has allowed a more accurate assessment of the presence, location, extent, and aggressiveness of prostate cancer both before and after treatment. This information has already demonstrated the ability to improve therapeutic planning for individual prostate cancer patients and shows great promise in the assessment of therapeutic response and the evaluation of new treatment regimes.

Clinical Protocols↗
PubMed2000

Imaging for recurrent prostate cancer.

Multiple imaging modalities are available to evaluate recurrent prostate cancer following primary treatment with RP, RT, or cryo-surgery. These tests must be used in close conjunction with clinical parameters, such as the characteristics of the tumor itself (grade, stage) as well as specific PSA characteristics that can help predict the sites of probable recurrence. Figure 19 represents an algorithm of how patients can be monitored for recurrence according to their mode of primary treatment. As more treatments become available for recurrent prostate cancer, it will be necessary to monitor disease response with many of the imaging modalities discussed in this article.

Algorithms↗
PubMed2000

Complex adnexal masses: detection and characterization with MR imaging--multivariate analysis.

PURPOSE: To evaluate the accuracy of magnetic resonance (MR) imaging in the detection and characterization of complex adnexal masses, with particular reference to the findings predictive of malignancy, role of gadolinium-enhanced contrast material, and observer variability. MATERIALS AND METHODS: Preoperative MR imaging of the pelvis was performed in 128 consecutive patients with clinically or ultrasonographically detected complex adnexal masses. Histopathologic examination demonstrated 187 masses, 96 of which were malignant. MR imaging studies were prospectively and independently reviewed by two radiologists, one of whom reevaluated the studies after a 6-month interval. The predictive value of MR imaging findings was determined with multivariate logistic regression analysis. The value of gadolinium enhancement was assessed by using receiver operating characteristic analysis. Inter- and intraobserver variabilities were assessed by using weighted K statistics. RESULTS: Gadolinium-enhanced MR imaging depicted 176 (94%) of 187 adnexal masses, with an overall accuracy for the diagnosis of malignancy of 93%. The MR imaging findings that were most predictive of malignancy were necrosis in a solid lesion (odds ratio, 107) and vegetations in a cystic lesion (odds ratio, 40). Use of gadolinium-based contrast material contributed significantly to lesion characterization. Interobserver (K, 0.79-0.85) and intraobserver (K, 0.84-0.86) agreement were excellent. CONCLUSION: Gadolinium-enhanced MR imaging is highly accurate in the detection and characterization of complex adnexal masses, with excellent inter- and intraobserver agreement.

Adolescent↗
PubMed2000

Normal and hypoplastic fetal lungs: volumetric assessment with prenatal single-shot rapid acquisition with relaxation enhancement MR imaging.

PURPOSE: To determine which parameters are most closely correlated with normal fetal total lung volume and to investigate the use of these parameters in the evaluation of fetal pulmonary hypoplasia. MATERIALS AND METHODS: Single-shot rapid acquisition with relaxation enhancement (RARE) magnetic resonance (MR) imaging was used to perform planimetric measurement of total lung volume in 46 fetuses at 18-32 weeks gestation. Total lung volume was correlated with gestational age, and biometric parameters in fetuses were correlated with normal chest findings at ultrasonography (US) (n = 24). This analysis was used to evaluate relative lung volume in fetuses suspected of having pulmonary hypoplasia (n = 22). RESULTS: Normal fetal total lung volume was strongly correlated with liver volume measured at MR imaging (r = 0.94), fetal weight estimated at US (r = 0.93), head circumference measured at US (r = 0.90), and gestational age (r = 0.87). In fetuses suspected of having pulmonary hypoplasia, the relative lung volume varied from 4.6% to 81.6% when the observed total lung volume was expressed as a percentage of the predicted total lung volume. CONCLUSION: Normal fetal total lung volume is strongly correlated with biometric measurements. Relative fetal lung volume can be calculated by expressing the observed volume as a percentage of the predicted volume calculated from biometric measurements; knowledge of the relative fetal lung volume assists in the confirmation and quantification of fetal pulmonary hypoplasia.

Adolescent↗
PubMed2000

Prediction of deep myometrial invasion in patients with endometrial cancer: clinical utility of contrast-enhanced MR imaging-a meta-analysis and Bayesian analysis.

PURPOSE: To determine if, in a patient with an endometrial cancer, in addition to the knowledge of tumor grade, preoperative magnetic resonance (MR) imaging findings contribute to treatment stratification and specialist referral. MATERIALS AND METHODS: By using a MEDLINE literature search and institutional pathology reports, pretest probabilities for myometrial invasion were correlated with tumor grade. Likelihood ratios (LRs) were obtained through summary receiver operating characteristics. RESULTS: The mean pretest probabilities of deep myometrial invasion were derived from seven articles (1,875 patients) and from 125 institutional pathology reports. LRs for the prediction of myometrial invasion with contrast-enhanced MR imaging were derived from nine studies (742 patients); positive and negative LRs were 10.11 and 0.1, respectively. The mean weighted pretest probabilities of deep myometrial invasion in patients with tumor grades 1, 2, or 3 were 13%, 35%, or 54%, respectively. Posttest probabilities of deep myometrial invasion for grades 1, 2, or 3 increased to 60%, 84%, or 92%, respectively, for positive and decreased to 1%, 5%, or 10%, respectively, for negative MR imaging findings. CONCLUSION: Use of contrast-enhanced MR imaging significantly affects the posttest probability of deep myometrial invasion in patients with all grades of endometrial cancer and could be used to select patients for specialist referral.

Bayes Theorem↗
PubMed2000

US characterization of ovarian masses: a meta-analysis.

PURPOSE: To compare the effectiveness of current ultrasonographic (US) techniques for characterizing ovarian masses. MATERIALS AND METHODS: Through a MEDLINE literature search, articles with imaging-histopathologic correlation and data that allowed calculation of contingency tables were identified. Results of morphologic assessment, Doppler US, color Doppler flow imaging, and combined techniques were compared. RESULTS: Among 89 data sets from 46 included studies (5,159 subjects), 35 sets used morphologic information, 36 measured Doppler US indexes, 10 assessed tumor vascularity with color Doppler flow imaging, and eight used combined techniques. Summary receiver operating characteristic curves revealed significantly higher performance for combined techniques than for morphologic information (P: =.003), Doppler US indexes (P: =.003), or color Doppler flow imaging alone (P: =.001). The Q* point (and 95% CI) for combined techniques was 0.92 (0.87, 0.96) versus 0. 85 (0.83, 0.88) for morphology, 0.82 (0.78, 0.86) for Doppler US, and 0.73 (0.58, 0.87) for color Doppler flow imaging. Morphologic assessment showed a trend toward better performance than color Doppler flow imaging (P: =.09) or Doppler US indexes (P: =.07). Doppler US index results were better in earlier studies (P: =.005). CONCLUSION: Combined US techniques and a diagnostic algorithm perform significantly better than morphologic assessment, color Doppler flow imaging, or Doppler US indexes alone in characterizing ovarian masses.

Analysis of Variance↗
PubMed2000

Sextant localization of prostate cancer: comparison of sextant biopsy, magnetic resonance imaging and magnetic resonance spectroscopic imaging with step section histology.

PURPOSE: We compared the accuracy of endorectal magnetic resonance imaging (MRI) and magnetic resonance spectroscopic imaging with that of sextant biopsy for the sextant localization of prostate cancer. MATERIALS AND METHODS: Sextant biopsy, MRI, magnetic resonance spectroscopic imaging and radical prostatectomy with step section histology were done in 47 patients with prostate cancer. For each sextant we categorized biopsy and imaging results as positive or negative for cancer. Step section histology was used as the standard of reference. RESULTS: For sextant localization of prostate cancer MRI and magnetic resonance spectroscopic imaging were more sensitive but less specific than biopsy (67% and 76% versus 50%, and 69% and 68% versus 82%, respectively). The sensitivity of sextant biopsy was significantly less in the prostate apex than in the mid prostate or prostate base (38% versus 52% and 62%, respectively). MRI and magnetic resonance spectroscopic imaging had similar efficacy throughout the prostate compared with biopsy only as well as better sensitivity and specificity in the prostate apex (60% and 75%, and 86% and 68%, respectively). A positive biopsy or imaging result had 94% sensitivity for cancer and concordant positivity by all 3 tests was highly specific at 98%. CONCLUSIONS: Overall MRI and magnetic resonance spectroscopic imaging have accuracy similar to biopsy for intraprostatic localization of cancer and they are more accurate than biopsy in the prostate apex. These 2 imaging modalities may supplement biopsy results by increasing physician confidence when evaluating intraprostatic tumor location, which may be important for planning disease targeted therapy.

Aged↗