PubMed Health⌕ Search

Biomedical subjects

Mukesh G Harisinghani

Publications and source records attributed to Mukesh G Harisinghani.

At least 19 recordsLinked to original sources
PubMed2006

Lymphotropic nanoparticle enhanced MR imaging (LNMRI) technique for lymph node imaging.

Accurate nodal staging is important in the management of any primary malignancy. The presence of nodal metastases has both therapeutic and prognostic implications. Lymphotropic nanoparticles are a new class of MRI contrast agents, which are promising in detecting minimal metastatic nodal disease particularly in normal sized lymph nodes. This paper discusses the technique and interpretation of lymphotropic nanoparticle enhanced MRI (LNMRI) and reviews the various trials evaluating nodal staging with ferumoxtran-10 enhanced MRI.

Contrast Media↗
PubMed2006

Ferumoxtran-10-enhanced MR lymphangiography: does contrast-enhanced imaging alone suffice for accurate lymph node characterization?

OBJECTIVE: Ferumoxtran-10 is a lymphotropic MR contrast agent that is currently under investigation. It has been shown to be effective in staging lymph nodes of patients with various primary malignancies. The current technique with ferumoxtran-10 involves imaging before and 24 hr after contrast administration. The purpose of this study was to evaluate the accuracy of ferumoxtran-10-enhanced images alone in characterizing lymph nodes for oncologic staging 24 hr after contrast enhancement. MATERIALS AND METHODS: Seventy-seven patients (58 men, 19 women) with proven primary cancer (bladder [n = 20], breast [n = 10], endometrial [n = 1], renal [n = 3], penile [n = 4], prostate [n = 31], rectal [n = 1], testicular [n = 5], and ureteral [n = 2]) who were scheduled for surgical lymph node dissection were enrolled in the study. In these patients, 169 lymph nodes (mean size, 11.2 mm) were evaluated on T2*-weighted gradient-refocused echo MRI at l.5 T both before and 24-36 hr after the IV administration of ferumoxtran-10 (2.6 mg Fe/kg). Two blinded reviewers with differing levels of interpreting experience separately performed qualitative image evaluation. A 6-point scale was used to characterize lymph nodes on contrast-enhanced images alone and on combined unenhanced and contrast-enhanced images. Receiver operating characteristic (ROC) analysis was performed separately for both reviewers. RESULTS: Of the 169 lymph nodes evaluated, 55 were benign and 114 malignant by histopathologic analysis. The results of the ROC analysis comparing contrast-enhanced images ([A(z) = area under ROC curve] reviewer 1, A(z) = 0.92; reviewer 2, A(z) = 0.94) alone with combined unenhanced and contrast-enhanced images (reviewer 1, A(z) = 0.94; reviewer 2, A(z) = 0.93) showed a statistically significant difference (p = 0.01) for reviewer 1 but no difference for reviewer 2 (p = 0.88). Reviewer 2 was more experienced in interpreting ferumoxtran-10-enhanced images than reviewer 1. CONCLUSION: On ferumoxtran-10-enhanced MR lymphangiography, contrast-enhanced images alone may suffice for lymph node characterization. However, a certain level of interpretation experience may be required before contrast-enhanced images can be used alone.

Adult↗
PubMed2005

Diagnostic performance of nanoparticle-enhanced magnetic resonance imaging in the diagnosis of lymph node metastases in patients with endometrial and cervical cancer.

PURPOSE: Lymph node metastases affect management and prognosis of patients with gynecologic malignancies. Preoperative nodal assessment with computed tomography or magnetic resonance imaging (MRI) is inaccurate. A new lymph node-specific contrast agent, ferumoxtran-10, composed of ultrasmall particles of iron oxide (USPIO), may enhance the detection of lymph node metastases independent of node size. Our aim was to compare the diagnostic performance of MRI with USPIO against standard size criteria. METHODS: Forty-four patients with endometrial (n = 15) or cervical (n = 29) cancer were included. MRI was performed before and after administration of USPIO. Two independent observers viewed the MR images before lymph node sampling. Lymph node metastases were predicted using size criteria and USPIO criteria. Lymph node sampling was performed in all patients. RESULTS: Lymph node sampling provided 768 pelvic or para-aortic nodes for pathology, of which 335 were correlated on MRI; 17 malignant nodes were found in 11 of 44 patients (25%). On a node-by-node basis, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) by size criteria were 29%*, 99%, 56%, and 96%, and by USPIO criteria (reader 1/reader 2) were 93%/82%* (*P = .008/.004), 97%/97%, 61%/59%, and 100%/99%, respectively (where [*] indicates the statistical difference of P = x/x between the two results marked by the asterisk). On a patient-by-patient basis, sensitivity, specificity, PPV, and NPV by size criteria were 27%*, 94%, 60%, and 79%, and by USPIO criteria (reader 1/reader 2) were 100%/91%* (*P = .031/.06), 94%/87%, 82%/71%, and 100%/96%, respectively. The kappa statistic was 0.93. CONCLUSION: Lymph node characterization with USPIO increases the sensitivity of MRI in the prediction of lymph node metastases, with no loss of specificity. This may greatly improve preoperative treatment planning.

Adult↗
PubMed2005

A pilot study of lymphotrophic nanoparticle-enhanced magnetic resonance imaging technique in early stage testicular cancer: a new method for noninvasive lymph node evaluation.

OBJECTIVES: To evaluate whether lymphotrophic nanoparticle-enhanced magnetic resonance imaging (LNMRI) can be used as a method for detecting metastatic disease within retroperitoneal nodes in patients with testicular cancer. METHODS: Stage I testicular cancer patients were prospectively enrolled and underwent a pelvic MRI both before and 24 hours after intravenous ferumoxtran-10 administration. Nodal sampling was performed by computed tomography-guided biopsy or laproscopic surgery and reviewed by a pathologist without knowledge of the LNMRI results. RESULTS: In 18 patients, 42 nodes were sampled, of which 25 were benign and 17 were malignant. The sensitivity of LNMRI for malignant lymph node involvement was 88.2%, specificity was 92%, and the accuracy was 90.4%. On the other hand, the sensitivity of size criteria for detecting malignant nodes was 70.5%, the specificity was 68%, and the accuracy was 69%. CONCLUSIONS: Lymphotrophic nanoparticle-enhanced MRI is safe and accurate for detecting nodal metastases in patients with testicular cancer. Lymphotrophic nanoparticle-enhanced MRI yields higher sensitivity and specificity when compared with unenhanced MRI or conventional CT scanning. Although our results are encouraging, the precise role of this tool in early stage testicular cancer remains to be determined.

Adult↗
PubMed2005

Palpable right breast mass in a pregnant woman.

BACKGROUND: A 29-year-old female presented with a palpable right breast mass at a 12-week prenatal visit. She had no family history of breast or ovarian cancer. Ultrasound revealed a 3 cm lobulated mass, which was confirmed to be malignant by a core biopsy. Postmastectomy pathology at 15 weeks' gestation demonstrated this mass to be a stage T2N0M0 high-grade invasive ductal carcinoma with 0/20 axillary nodes involved. A staging CT scan postpartum showed an enlarged right internal mammary lymph node, confirmed by MRI as suspicious for malignancy. INVESTIGATIONS: Physical examination, breast ultrasound, core biopsy, mastectomy, CT scan, MRI. DIAGNOSIS: Pregnancy-associated breast carcinoma. MANAGEMENT: Mastectomy, chemotherapy and radiotherapy.

Adult↗
PubMed2005

CT and fluoroscopically guided percutaneous embolization treatment of a pseudoaneurysm associated with pancreatitis.

A novel approach to embolization treatment with a cyanoacrylate solution for a bleeding pseudoaneurysm associated with pancreatitis is described in the setting of a critically ill patient. Computed tomography and a C-arm fluoroscopic unit were used to guide percutaneous placement of a needle and injection of the embolic material. This technique represents an alternative form of embolization when traditional angiographic techniques are not possible.

Aneurysm, False↗
PubMed2005

Fungus-infected fluid collections in thorax or abdomen: effectiveness of percutaneous catheter drainage.

PURPOSE: To retrospectively evaluate the effectiveness of percutaneous catheter drainage in the treatment of fungus-infected fluid collections in the thorax or abdomen and to identify any factor that may be predictive of a poor clinical outcome. MATERIALS AND METHODS: Approval for this study was obtained from the hospital ethics subcommittee on human studies. Because the study was retrospective, patient informed consent was not required. This study was compliant with the Health Insurance Portability and Accountability Act. Retrospective analysis was performed of cases of fungus-infected fluid collections in the thorax or abdomen treated by using percutaneous catheter drainage in 60 patients (36 male and 24 female patients; mean age, 57 years; range, 2 months to 91 years) during 5 years. The patient medical records were reviewed to identify recognized factors for predisposition to fungal infection. The details of percutaneous catheter drainage and microbiologic findings were recorded. The technical success (ability of catheters placed to drain collections treated) and the clinical success (ability of patients to recover fully without surgery) of percutaneous catheter drainage were determined. A multifactor logistic regression analysis was performed to identify any clinical or microbiologic factor predictive of a poor clinical outcome. RESULTS: Seventy-three fungus-infected fluid collections were drained in 60 patients. The collections originated from the pleura (n = 6), mediastinum (n = 2), liver (n = 3), pancreas (n = 5), obstructed biliary or urinary tract (n = 9), gallbladder (n = 1), and abdominopelvic area (n = 47). The technical success rate for catheter drainage was 79% (41 of 52 patients); the clinical success rate, 57% (34 of 60 patients). Twenty (33%) patients died from all causes during hospital admission. Multifactor logistic regression analysis was used to identify predictors of a poor clinical outcome; complexity of collection, history of malignancy, and admission to intensive care unit were significant (P < .03) and independent predictors. CONCLUSION: Despite a moderately high technical success rate with percutaneous catheter drainage of fungus-infected fluid collections, clinical success rate was much lower. Both imaging appearance (complexity of collection) and clinical factors (history of malignancy, admission to intensive care unit) influenced prognosis.

Abdomen↗
PubMed2004

Sensitive, noninvasive detection of lymph node metastases.

BACKGROUND: Many primary malignancies spread via lymphatic dissemination, and accurate staging therefore still relies on surgical exploration. The purpose of this study was to explore the possibility of semiautomated noninvasive nodal cancer staging using a nanoparticle-enhanced lymphotropic magnetic resonance imaging (LMRI) technique. METHODS AND FINDINGS: We measured magnetic tissue parameters of cancer metastases and normal unmatched lymph nodes by noninvasive LMRI using a learning dataset consisting of 97 histologically proven nodes. We then prospectively tested the accuracy of these parameters against 216 histologically validated lymph nodes from 34 patients with primary cancers, in semiautomated fashion. We found unique magnetic tissue parameters that accurately distinguished metastatic from normal nodes with an overall sensitivity of 98% and specificity of 92%. The parameters could be applied to datasets in a semiautomated fashion and be used for three-dimensional reconstruction of complete nodal anatomy for different primary cancers. CONCLUSION: These results suggest for the first time the feasibility of semiautomated nodal cancer staging by noninvasive imaging.

Adult↗
PubMed2004

Urinary bladder cancer: preoperative nodal staging with ferumoxtran-10-enhanced MR imaging.

PURPOSE: To prospectively evaluate ferumoxtran-10-enhanced magnetic resonance (MR) imaging for nodal staging in patients with urinary bladder cancer. MATERIALS AND METHODS: Fifty-eight patients with proved bladder cancer were enrolled. Results of MR imaging performed before and after injection of ferumoxtran-10 were compared with histopathologic results in surgically removed lymph nodes. High-spatial-resolution three-dimensional T1-weighted magnetization-prepared rapid acquisition gradient-echo (voxel size, 1.4 x 1.4 x 1.4 mm) and T2*-weighted gradient-echo (voxel size, 0.8 x 0.8 x 3.0 mm) sequences were performed before and 24 hours after injection of ferumoxtran-10 (2.6 mg iron per kilogram of body weight). On precontrast images, lymph nodes were defined as malignant by using size and shape criteria (round node, >8 mm; oval, >10 mm axial diameter). On postcontrast images, nodes were considered benign if there was homogeneous decrease in signal intensity and malignant if decrease was absent or heterogeneous. Qualitative evaluation was performed on a node-to-node basis. Sensitivity, specificity, predictive values, and accuracy were evaluated with logistic regression analysis. RESULTS: In 58 patients, 172 nodes imaged with use of ferumoxtran-10 were matched and correlated with results of node dissection. Of these, 122 were benign and 50 were malignant. With nodal size and shape criteria, accuracy, sensitivity, specificity, and positive and negative predictive values on precontrast images were 92%, 76%, 99%, 97%, and 91%, respectively; corresponding values on postcontrast images were 95%, 96%, 95%, 89%, and 98%. In the depiction of pelvic metastases, sensitivity and negative predictive value improved significantly at postcontrast compared with those at precontrast imaging, from 76% to 96% (P < .001) and from 91% to 98% (P < .01), respectively. At postcontrast imaging, metastases (4-9 mm) were prospectively found in 10 of 12 normal-sized nodes (<10 mm); these metastases were not detected on precontrast images. Postcontrast images also showed lymph nodes that were missed at pelvic node dissection in two patients. CONCLUSION: Ferumoxtran-10-enhanced MR imaging significantly improves nodal staging in patients with bladder cancer by depicting metastases even in normal-sized lymph nodes.

Contrast Media↗
PubMed2004

MR imaging staging of pelvic lymph nodes.

Accurate pelvic nodal staging is important in the workup of many pelvic tumors for assessing prognosis and directing therapy. Advances in diagnostic imaging have played an integral role in the staging of these tumors. Cross-sectional imaging, including MR imaging,however, uses size criteria and morphology to infer malignancy within a node,which is neither sensitive nor specific. This article reviews the normal pelvic nodal anatomy and techniques of conventional MR imaging for optimal nodal evaluation as well as introducing the recent technique of ultra small supraparamagnetic iron oxide(USPIO)-enhanced MR lymphangiography, which uses nodal function rather than structural criteria in assessing for metastatic nodes.

Contrast Media↗
PubMed2004

Current concepts in lymph node imaging.

The accurate identification and characterization of lymph nodes by imaging has important therapeutic and prognostic significance in patients with newly diagnosed cancers. The presence of nodal metastases limits the therapeutic options and also generally indicates worse prognosis in patients. Thus, it becomes crucial to have this information before commencing therapy. Current cross-sectional imaging modalities rely on insensitive size and morphologic criteria and, thus, lack the desired accuracy for characterizing lymph nodes. This is mainly because metastases can be present in non-enlarged lymph nodes and not all enlarged nodes are malignant. PET has overcome some of these limitations but is still constrained by current resolution limits for small nodal metastases. This has fueled the development of targeted techniques for nodal imaging and characterization as outlined in this article. In the past few years, studies have shown that these newer imaging techniques can bridge some of the limitations of existing imaging for nodal characterization and thereby provide the much-needed staging information before the initiation of therapy.

Anatomy, Cross-Sectional↗
PubMed2003

Transgluteal approach for percutaneous drainage of deep pelvic abscesses: 154 cases.

PURPOSE: To assess the effectiveness of a computed tomographic (CT) image-guided transgluteal approach for percutaneous drainage of deep pelvic abscesses as an alternative to surgical drainage. MATERIALS AND METHODS: The medical records of 140 patients who underwent percutaneous CT-guided transgluteal drainage of 154 deep pelvic abscesses were reviewed to determine the origins, location, and size of the abscesses; volume of initial aspirate; organisms identified in fluid culture; duration of catheter drainage; incidence of catheter-related pain and procedure-related complications; and short- and long-term outcomes. The resultant data were analyzed with a Fisher exact test for difference in the incidence of postprocedural catheter-site pain between transpiriformis and infrapiriformis approaches. RESULTS: The origins of the pelvic abscesses included postoperative fluid collection (n = 115), perforating appendicitis (n = 6), diverticulitis (n = 16), tubo-ovarian inflammation (n = 5), Crohn disease (n = 10), and internal bowel fistula due to irradiation (n = 2). The abscesses were 4-12 cm in diameter. The volume of the aspirate was 5-310 mL. Laboratory cultures of the aspirate grew mixed flora, but the organism most frequently isolated was Escherichia coli. Catheters were removed after a mean of 8 days. In 134 (96%) of 140 patients, there was complete resolution of the abscess following transgluteal drainage, without subsequent surgery. In six of 140 (4%) patients, incomplete resolution necessitated subsequent surgery for postoperative fluid collection (n = 3), diverticulitis (n = 2), or perforating appendicitis (n = 1). Complications of transgluteal drainage were rare and included hemorrhage in three (2%) of the 140 patients. There was no procedure-related mortality. A transpiriformis approach was significantly more likely to be associated with postprocedural pain (P <.001) than was an infrapiriformis approach. CONCLUSION: Percutaneous CT-guided transgluteal drainage is a safe and effective alternative to surgery for deep pelvic abscesses. Major complications are rare.

Abscess↗
PubMed2003

Noninvasive detection of clinically occult lymph-node metastases in prostate cancer.

BACKGROUND: Accurate detection of lymph-node metastases in prostate cancer is an essential component of the approach to treatment. We investigated whether highly lymphotropic superparamagnetic nanoparticles, which gain access to lymph nodes by means of interstitial-lymphatic fluid transport, could be used in conjunction with high-resolution magnetic resonance imaging (MRI) to reveal small nodal metastases. METHODS: Eighty patients with presurgical clinical stage T1, T2, or T3 prostate cancer who underwent surgical lymph-node resection or biopsy were enrolled. All patients were examined by MRI before and 24 hours after the intravenous administration of lymphotropic superparamagnetic nanoparticles (2.6 mg of iron per kilogram of body weight). The imaging results were correlated with histopathological findings. RESULTS: Of the 334 lymph nodes that underwent resection or biopsy, 63 (18.9 percent) from 33 patients (41 percent) had histopathologically detected metastases. Of these 63 nodes, 45 (71.4 percent) did not fulfill the usual imaging criteria for malignancy. MRI with lymphotropic superparamagnetic nanoparticles correctly identified all patients with nodal metastases, and a node-by-node analysis had a significantly higher sensitivity than conventional MRI (90.5 percent vs. 35.4 percent, P<0.001) or nomograms. CONCLUSIONS: High-resolution MRI with magnetic nanoparticles allows the detection of small and otherwise undetectable lymph-node metastases in patients with prostate cancer.

Aged↗
PubMed2003

Evaluation of simethicone-coated cellulose as a negative oral contrast agent for abdominal CT.

RATIONALE AND OBJECTIVES: Because of the increased clinical use of computed tomography (CT) for imaging the abdominal vasculature and urinary tract, there is a need for negative contrast agents. The authors undertook this study to assess the suitability of simethicone-coated cellulose (SCC), which is approved for use as an oral contrast agent in sonography, for use as a negative oral contrast agent in abdominal CT. MATERIALS AND METHODS: This prospective study involved 40 adult patients scheduled to undergo abdominal CT for the evaluation of hematuria. Prior to scanning, 20 subjects received 800 mL of SCC and 20 received 800 mL of water as an oral contrast agent. Imaging was performed with a multi-detector row helical scanner in two phases, according to the abdominal CT protocol used for hematuria evaluation at the authors' institution. The first, "early" phase began an average of 15 minutes after the ingestion of contrast material; the second, "late" phase began an average of 45 minutes after the ingestion of contrast material. Blinded analysis was performed by three abdominal radiologists separately, using a three-point scale (0 = poor, 1 = acceptable, 2 = excellent) to assess the effectiveness of SCC for marking the proximal, middle, and distal small bowel. Average scores for enhancement with SCC and with water were obtained and compared. Statistical analysis was performed with a Wilcoxon signed-rank test. RESULTS: SCC was assigned higher mean scores than water for enhancement in each segment of the bowel, both on early-phase images (0.8-1.35 for SCC vs 0.6-1.1 for water) and on late-phase images (1.1-1.4 vs 0.81-0.96). Bowel marking with SCC, particularly in the jejunum and ileum, also was rated better than that with water in a high percentage of patients. The differences between the scores for water and for SCC, however, were not statistically significant (P > .05). CONCLUSION: SCC is effective as a negative oral contrast agent for small bowel marking at CT.

Administration, Oral↗
PubMed2003

Small bowel CT fat density target sign in chronic radiation enteritis.

On CT, a thickened intestinal wall configured with a middle layer of low attenuation surrounded on each side by layers of higher attenuation has been termed the target sign. The presence of fat within the submucosal layer of the small intestine is a well-known manifestation of Crohn's disease, but has not been reported in other chronic intestinal diseases. We describe CT findings of fat density target sign in a patient with prior radiation.

Adipose Tissue↗