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Sanjay Saini

Publications and source records attributed to Sanjay Saini.

67 records · Page 4Linked to original sources
PubMedDate not supplied

Radiological measurement of breast cancer metastases to lung and liver: comparison between WHO (bidimensional) and RECIST (unidimensional) guidelines.

PURPOSE: Radiologic assessment of "response-to-treatment" during clinical trials of anticancer drugs has been conventionally based on bidirectional tumor measurement. Recently, the revised guidelines were published, which recommended unidirectional tumor measurements. The purpose of this study was to compare response to treatment between the two measurement techniques in breast cancer patients with lung and liver metastases. METHOD: Contrast-enhanced computed tomography studies of 86 breast cancer patients who had lung (n = 27) and liver (n = 59) metastases and who were enrolled in a phase-III oncology trial were evaluated before initiation of treatment and at 6 months after treatment. Lesions were measured by subspecialist radiologists on digitized images using electronic calipers. The largest diameter of the lesions was extracted from bidimensional measurements. Response to treatment was categorized into one of four categories: complete response indicating lesion disappearance, partial response indicating >30% decrease in tumor diameter, or >50% reduction in tumor area, disease progression indicating >20% increase in tumor diameter, or >25% increase in tumor area, and stable disease (neither complete response, partial response, nor disease progression). Response to treatment between the two measurement techniques was compared statistically using the chi2 test. RESULTS: Response to treatment was concordant in 76 patients between unidimensional and bidimensional measurement techniques. In 5 patients (2 lung and 3 liver metastases) the response assessment was improved using unidimensional criteria and in 5 patients (2 lung and 3 liver metastases) the response was worse using unidimensional guidelines. Thus, the overall response rate was 50% for both unidimensional and bidimensional measurement techniques. There was no statistical difference between the two techniques. CONCLUSION: Unidimensional measurements are appropriate for measuring the size of liver and lung metastases for determining response to treatment during clinical testing of oncologic drugs.

Antineoplastic Agents↗
PubMedDate not supplied

Multidetector-row computed tomography angiography for planning intra-arterial chemotherapy pump placement in patients with colorectal metastases to the liver.

PURPOSE: The purpose of this study was to evaluate the use of multidetector computed tomography (MDCT) in the preoperative arterial evaluation of patients scheduled to undergo intra-arterial chemotherapy pump placement. METHODS: Computed tomography scans of 30 patients with hepatic malignancies who were imaged with multiphase MDCT angiography for intra-arterial chemotherapy pump placement were retrospectively analyzed. Dual-phase helical CT was performed, and the arterial phase images were processed to depict the arterial anatomy and to identify pertinent anomalies. All findings were compared and correlated with surgical findings or catheter angiography if surgery was contraindicated. RESULTS: Arterial anomalies identified on CT angiography in 20 of 30 patients included a replaced right hepatic artery (RHA; n = 6) or left hepatic artery (LHA; n = 8), a replaced common hepatic artery (n = 1), an accessory RHA (n = 2) or LHA (n = 6), a replaced gastroduodenal artery (GDA; n = 2), an extrahepatic connection between the accessory RHA and the replaced RHA (n = 1), and a common origin composed of the GDA and RHA and LHA (n = 2). There were no additional arteries or anomalies identified by catheter angiography, when available, or during surgery. Only 1 variant, an accessory hepatic artery, was not located during surgery. In 2 patients, the surgical team decided that pump placement was not feasible because of overly complex anatomy as determined by CT angiography. Computed tomography angiography showed an overall sensitivity of 100% and specificity of 97%. CONCLUSIONS: Multidetector computed tomography angiography is accurate for the preoperative evaluation of normal and aberrant hepatic vasculature in patients under consideration for intra-arterial chemotherapy pump placement. Axial images alone permit recognition of vascular anomalies, including complex anatomy. Nevertheless, 3-dimensional rendering is useful to evaluate complex vascular anatomy and does not require catheter angiographic confirmation. In addition to aiding in selecting patients ideal for pump placement, MDCT permits noninvasive planning of their surgical approach.

Aged↗
PubMedDate not supplied

Using the K-edge to improve contrast conspicuity and to lower radiation dose with a 16-MDCT: a phantom and human study.

PURPOSE: To study the effect of tube current (milliamperes; mA) and potential (peak kilovolt; kVp) on the attenuation values and contrast-to-noise ratios of iodine- and gadolinium-based contrast media (CM) for computed tomography angiography (CTA). MATERIALS AND METHODS: Phantom Study: A water-filled phantom with five 20-mL syringes filled with 1:20 dilution of 282, 300, 370, and 400 milligrams of iodine per milliliter concentration CM and gadopentetate dimeglumine (Magnevist, Berlex Laboratories, Wayne, NJ, 0.5 mol/L) was scanned with a 16-multidetector CT using 80, 100, 120, and 140 kVp and 500-millisecond gantry rotation time. The milliampere was either fixed at 100, 200, 300, and 380 or automatically adjusted with noise indices of 15, 20, and 25 or manually adjusted to maintain a constant image noise. The attenuation value (Hounsfield unit; HU) and its standard deviation of CM in each syringe and of the water phantom were obtained. Statistical analysis was performed to determine difference between attenuation values and contrast medium-to-water contrast-to-noise ratios at various kVp and mA selection. Human Study: Three groups of patients had CTA for abdominal aortic aneurysm with similar computed tomography parameters, varying only in kVp selection of either 100 (group A), 120 (group B), or 140 (group C). Another group (group D) had CTA at 100 kVp but with the CM volume reduced to 60%. The CTA studies were evaluated for the quality of axial and 3D images; attenuation values in the aorta, superior mesenteric artery, and iliac arteries; image noise; and scanner-estimated radiation dose. Statistical analysis was performed to determine the difference in image quality and radiation dose among the groups. RESULTS: Phantom Study: In comparison with 140 kVp, regardless of selected milliampere or noise indices, images acquired at 80, 100, and 120 kVp showed 90.8% to 94.2%, 47% to 49.7%, and 18.9% to 20.7% (P<0.0001) increase in HU of iodine-based CM, respectively, and 62.9%, 39.6%, and 16.8% (P<0.0001) increase in HU of gadolinium-based CM, respectively. Human Study: The axial images in all the groups were diagnostically acceptable. There was significantly inferior quality of axial images associated with greater image noise in group A and group D (P<0.01) in comparison with group C, but there was no difference in the quality of 3D images among the 4 groups. In comparison with group C, there was significantly higher attenuation of the aorta, superior mesenteric artery, and iliac arteries in group A (P<0.01), group B (P<0.05), and group D (P<0.01). The radiation dose (CT dose index volume) decreased to 12+/-4 in groups A and D compared with 17+/-4 in group B and 24+/-5 in group C. CONCLUSIONS: Lower kVp increases the attenuation of iodinated and gadolinium CM. CTA of the abdominal aorta performed at low kVp results in higher attenuation in aorta with reduced radiation dose and without degrading the diagnostic image quality. The iodinated CM volume can be reduced by reducing kVp during CTA.

Adolescent↗
PubMedDate not supplied

Radiation exposure and projected risks with multidetector-row computed tomography scanning: clinical strategies and technologic developments for dose reduction.

A substantial increase in computed tomography (CT) scanning with availability of state-of-the-art multidetector-row CT scanners has generated debate about its safety and considerable interest in formulating clinical and technologic strategies to reduce radiation exposure. This review describes the magnitude of radiation exposure associated with CT scanning and projected radiation risks as well as clinical strategies and major technologic innovations for reducing radiation dose to patients undergoing CT scanning.

Humans↗
PubMedDate not supplied

Multidetector computed tomography technology: current status and emerging developments.

By virtue of its speed and isotropic resolution of thin slices, multidetector-row computed tomography (MDCT) offers unique advantages over previous single-detector-row CT, with improved temporal and spatial resolution. This review describes the historical perspective and growth trends of MDCT scanners and highlights the current status and emerging developments in multidetector technology based on presentations at the symposium "Advances in Multidetector CT," under the auspices of the Institute for Advanced Medical Education in Washington, DC.

Humans↗
PubMedDate not supplied

Distinguishing hepatic metastases from hemangiomas: qualitative and quantitative diagnostic performance through dual echo respiratory-triggered fast spin echo magnetic resonance imaging.

OBJECTIVE: To determine the relative value of qualitative (reader opinion) and quantitative (values derived from dual echo T2 fast spin echo [FSE]) measures in distinguishing hepatic metastases from hemangiomas. METHODS: Forty-nine patients with hemangiomas and 23 with metastases were studied with dual echo respiratory-triggered FSE and dynamic 2-dimensional spoiled gradient echo (GRE) imaging. Lesion T2 was estimated from signal intensity ratios on the first and second echoes. Two experienced radiologists independently evaluated groups of images based on 5 separate qualitative measures: first echo FSE, second echo FSE, first and second echo FSE, dynamic GRE, and all images together. RESULTS: The mean calculated T2s were 226 +/- 74 milliseconds for hemangiomas and 105 +/- 22 milliseconds for metastases (P < 0.001). A T2 cutoff of 130 milliseconds distinguished metastases from hemangiomas with a sensitivity of 94%, specificity of 91%, and accuracy of nearly 94%. There was no significant difference between the best quantitative measure and the best qualitative measure for either reader. CONCLUSION: Liver lesion T2 relaxation times calculated from dual echo FSE images provide information useful in discriminating metastases from hemangiomas, as does reader opinion.

Adult↗
PubMedDate not supplied

Evaluation of living liver transplant donors: method for precise anatomic definition by using a dedicated contrast-enhanced MR imaging protocol.

Liver transplantation from a living donor involves removal of part of the donor liver in a fashion that does not endanger its vascular supply or metabolic function. The radiologist plays an important role in evaluation of the living donor to define the conditions under which graft donation is contraindicated and to identify anatomic variations that may alter the surgical approach. In the past, diagnostic work-up of the donor involved costly and invasive tests. Currently, dynamic contrast material-enhanced computed tomography and magnetic resonance (MR) imaging are the imaging tests performed, each of which has advantages and limitations. MR imaging performed with liver-specific and extravascular contrast agents may be used as a single imaging test for comprehensive noninvasive evaluation of living liver transplant donors. MR imaging provides valuable information about variations in the vascular and biliary anatomy and allows evaluation of the hepatic parenchyma for diffuse or focal abnormalities.

Biliary Tract↗
PubMedDate not supplied

Preoperative hepatic vascular evaluation with CT and MR angiography: implications for surgery.

Partial liver resection for living donor transplantations and treatment of hepatic tumors is a major surgical undertaking, and detailed knowledge of the hepatic angioarchitecture is essential to ensure safe and successful liver surgery. Noninvasive imaging techniques such as computed tomographic (CT) and magnetic resonance (MR) angiography have begun to replace conventional catheter angiography for evaluation of the hepatic vascular anatomy. Multisection CT angiography and MR angiography are complementary modalities that permit comprehensive, accurate preoperative delineation of the hepatic vascular anatomy and evaluation of the parenchyma in patients undergoing liver surgery, thereby obviating multiple invasive studies including catheter angiography. Understanding a surgeon's perspective on liver surgery is critical so that the required information can be provided accurately with imaging. Both CT angiography and MR angiography have had a significant impact on the selection of candidates for liver surgery as well as on surgical technique.

Angiography↗
PubMedDate not supplied

Imaging diagnosis of cystic pancreatic lesions: pseudocyst versus nonpseudocyst.

Although the clinical, radiologic, and pathologic features of cystic pancreatic lesions are well known, preoperative diagnosis is difficult. Differentiation between a pancreatic pseudocyst and a cystic pancreatic neoplasm is crucial in determining the proper treatment. Careful evaluation of the patient's clinical history is important for accurate diagnosis of a pseudocyst. Clinical scenarios include a pseudocyst developing after acute pancreatitis and a pseudocyst superimposed on chronic pancreatitis. However, a pseudocyst in a patient with no clinical history of pancreatitis poses a diagnostic problem. The differential diagnosis of a neoplastic cystic lesion of the pancreas includes serous cystadenoma, mucinous cystic neoplasms, intraductal papillary mucinous tumor, and solid and papillary epithelial neoplasm. Definitive diagnosis is often possible when the lesion has a typical radiologic appearance, but in many cases characterization with imaging alone is impossible. Thin-section computed tomography with multiplanar reformation, magnetic resonance cholangiopancreatography, and endoscopic ultrasonography have emerged as modalities that can provide additional diagnostic information. Familiarity with the range of imaging appearances and awareness of the diagnostic strengths and limitations of each imaging modality are important for accurate diagnosis and management of cystic pancreatic lesions.

Adult↗
PubMedDate not supplied

Correlation of patient weight and cross-sectional dimensions with subjective image quality at standard dose abdominal CT.

OBJECTIVE: We evaluated the association between patients' weight and abdominal cross-sectional dimensions and CT image quality. MATERIALS AND METHODS: We prospectively evaluated 39 cancer patients aged more than 65 years with multislice CT scan of abdomen. All patients underwent equilibrium phase contrast-enhanced abdominal CT with 4 slices (from top of the right kidney) obtained at standard tube current (240-280 mA). All other scanning parameters were held constant. Patients' weight was measured just prior to the study. Cross-sectional abdominal dimensions such as circumference, area, average anterior abdominal wall fat thickness and, anteroposterior and transverse diameters were measured in all patients. Two subspecialty radiologists reviewed randomized images for overall image quality of abdominal structures using 5- point scale. Non-parametric correlation analysis was performed to determine the association of image quality with patients' weight and cross-sectional abdominal dimensions. RESULTS: A statistically significant negative linear correlation of 0.46, 0.47, 0.47, 0.58, 0.56, 0.54, and 0.56 between patient weight, anterior abdominal fat thickness, anteroposterior and transverse diameter, circumference, cross-sectional area and image quality at standard scanning parameters was found (p<0.01). CONCLUSION: There is a significant association between image quality, patients' weight and cross-sectional abdominal dimensions. Maximum transverse diameter of the abdomen has the strongest association with subjective image quality.

Aged↗
PubMedDate not supplied

Techniques, clinical applications and limitations of 3D reconstruction in CT of the abdomen.

Enhanced z-axis coverage with thin overlapping slices in breath-hold acquisitions with multidetector CT (MDCT) has considerably enhanced the quality of multiplanar 3D reconstruction. This pictorial essay describes the improvements in 3D reconstruction and technical aspects of 3D reconstruction and rendering techniques available for abdominal imaging. Clinical applications of 3D imaging in abdomen including liver, pancreaticobiliary system, urinary and gastrointestinal tracts and imaging before and after transplantation are discussed. In addition, this article briefly discusses the disadvantages of thin-slice acquisitions including increasing numbers of transverse images, which must be reviewed by the radiologist.

Adult↗