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S Saini

Publications and source records attributed to S Saini.

At least 199 records · Page 11Linked to original sources
PubMed1990

Percutaneous gastrostomy with gastropexy: experience in 125 patients.

We report our experience with radiologically guided percutaneous tube gastrostomy in 125 patients by using a gastropexy technique in which the anterior gastric wall is nonsurgically sutured to the anterior abdominal wall with percutaneously placed T-fasteners before catheter insertion. Short-term follow-up of up to 2 weeks was available in all patients. In 63 patients, long-term follow-up (greater than 4 weeks; average, 3.5 months; maximum, 1 year) was available. Catheter placement was successful in 124 (99%) of 125 patients, including three patients with anatomic changes after Bilroth II hemigastrectomy and two patients with failed endoscopic attempts. There were no deaths related to the procedure, and no patients required surgical intervention for complications attributable to the gastrostomy procedure. The 30-day mortality rate was 11% (n = 7). These deaths were due to cardiorespiratory arrest and were not attributable to the gastrostomy procedure. Major complications occurred in 1.6% (n = 1) and minor complications in 9.5% (n = 6). These results indicate that percutaneous gastrostomy with gastropexy is a safe and effective technique for placement of catheters in the stomach.

Adult↗
PubMed1990

Differentiation between small hepatic hemangiomas and metastases on MR images: importance of size-specific quantitative criteria.

We studied the feasibility of using MR imaging at 0.6 T to differentiate small hepatic hemangiomas from small metastases on the basis of quantitative criteria. Ninety-two liver masses up to 5 cm in diameter, including 51 proved hemangiomas (mean, 1.9 +/- 1.1 cm) and 41 proved metastases (mean, 1.9 +/- 1.2 cm) were analyzed. Lesions were divided into three groups on the basis of size (less than or equal to 1 cm, greater than 1- less than or equal to 2 cm, greater than 2- less than or equal to 5 cm). The ability to distinguish hemangiomas from metastases was examined by using differences in lesion/liver signal-intensity ratio (SIR) and contrast-to-noise ratio (CNR) on T2-weighted images (SE 2350/180). Receiver-operating-characteristic analysis for all lesions grouped together showed that differentiation based on SIR was superior to that based on CNR (p less than .05). The mean SIR of hemangioma and the difference between mean SIRs of hemangioma and metastasis decreased with lesion size (greater than 2- less than or equal to 5 cm: 6.11 +/- 2.61 vs 2.30 +/- 1.22; greater than 1- less than or equal to 2 cm: 4.47 +/- 1.56 vs 2.40 +/- 0.73; less than or equal to 1 cm: 3.59 +/- 0.92 vs 2.01 +/- 0.52). However, in each size group, the difference between the mean SIR of hemangioma and metastasis was statistically significant (p less than .0001). These observations suggest that MR imaging is useful in differentiating small hepatic hemangiomas from small metastases and suggest the need for establishing size-specific quantitative criteria for tissue characterization.

Diagnosis, Differential↗
PubMed1990

[Magnetic resonance tomography in hepatocellular carcinoma and idiopathic hemochromatosis].

A case of hepatocellular carcinoma in idiopathic hemochromatosis is discussed to illustrate the possible advantages of MR imaging. Since hepatic iron overload provides a natural source of paramagnetic contrast enhancement MRI should performed in preference to other investigative procedures to detect small and curative resectable hepatocellular carcinomas in patients with hemochromatosis.

Carcinoma, Hepatocellular↗
PubMed1990

Contrast-enhanced magnetic resonance imaging of the abdomen and pelvis.

Contrast media in magnetic resonance imaging (MRI) of the abdomen and pelvis are applied for various purposes; different substances and forms of application must be distinguished. Oral contrast agents are primarily used to enhance the discrimination of the intestine from the other organs and from pathological lesions. Clinical studies of i.v. contrast agents focus on two substances: gadolinium-diethylenetriaminepentaacetic acid (Gd-DTPA) and superparamagnetic iron oxide. Whereas dynamic Gd-DTPA-enhanced MRI improves the differential diagnosis of focal hepatic lesions, iron oxide is a promising agent for increasing the sensitivity of MRI in the detection of hepatic and splenic tumors. Dynamic Gd-DTPA-enhanced MRI of the kidney allows functional assessment of this organ; good demarcation of kidney tumors is only achieved during the early phase of a dynamic examination. In the assessment of adrenal lesions, dynamic Gd-DTPA-enhanced MRI permits better differentiation of adenoma from malignancy. Intravenous Gd-DTPA also appears to be useful in the staging of urinary bladder tumors to distinguish between superficial and infiltrating tumors. Although offering no major diagnostic advantage in the staging of cervical carcinomas, Gd-DTPA-enhanced MRI improves the discrimination of necrotic tumor portions of endometrial carcinoma and allows good differentiation of this lesion from fluid retained in the uterine cavity. Studies of new contrast agents for MRI of the abdomen, which have so far only been investigated in animal experiments, focus on liver imaging. These substance include hepatobiliary agents, Gd-DTPA-containing liposomes, and paramagnetic macromolecules.

Abdomen↗
PubMed1990

Percutaneous balloon dilatation of benign biliary strictures.

Percutaneous biliary dilatation is an effective alternative to surgical management of benign biliary strictures that has low morbidity and no reported mortality. Reported success rates for this procedure range from 40% to 90% depending on the size of the series, the type of patient being treated, and the length of follow-up period. The procedure is done in the fluoroscopy suite with an angioplasty balloon catheter. Transhepatic access is most common, but the procedure may be done via existing T-tube tracts or specially created jejunal loops. As the frequency of radical liver surgery such as liver transplant and radical trisegmentectomy rises, so too, the rate of biliary stricture is likely to rise, making percutaneous balloon dilatation an increasingly important tool in the interventional radiologist's armamentarium.

Catheterization↗
PubMed1989

Clinical use of a nonferromagnetic needle for magnetic resonance-guided biopsy.

Five patients who had liver lesions detected by magnetic resonance (MR) and/or computed tomography (CT) were biopsied using MR guidance with a specially designed nonferromagnetic needle. The 20-gauge needle was constructed from Type 316 stainless steel in order to maximize needle visibility and minimize needle-tip artifact. In all cases adequate tissue was obtained for diagnosis and no side effects were observed during the biopsy or on clinical follow-up despite the fact that the needle was within the patient in MR for an average of 30 min.

Biopsy, Needle↗
PubMed1989

Hepatic imaging and advanced endoscopic techniques.

Diseases of the liver and biliary tract can be diagnosed and potentially treated by a variety of radiologic modalities and endoscopic techniques. The imaging modalities of ultrasonography, computed tomography, nuclear scintigraphy and magnetic resonance are emphasized in this article. The current status of endoscopic retrograde cholangiopancreatography, sphincterotomy, biliary endoprostheses, cholangioscopy, endoscopic ultrasound, and laser lithotripsy is discussed.

Biliary Tract Diseases↗
PubMed1989

Central scars in primary liver tumors: MR features, specificity, and pathologic correlation.

Tumor scars were identified at pathologic study and magnetic resonance (MR) imaging in ten of 17 (59%) primary liver tumors (nine hepatocellular carcinomas, four giant hemangiomas, two hepatic adenomas, and two cases of focal nodular hyperplasia). Histopathologic examination revealed three types of scar tissue. Inflammatory scars (n = 4), with edema, necrosis, hypercellularity, and loose fibrous tissue, appeared hypointense relative to liver on T1-weighted images and hyperintense on T2-weighted images. Vascular scars (n = 3), predominantly composed of vascular channels traversing collagenous tissue, showed MR features similar to those of inflammatory scars. Collagenous scars (n = 3) appeared hypointense relative to liver on both T1-weighted and T2-weighted images. Central tumor scars are a frequent but nonspecific feature of both benign and malignant primary liver tumors.

Adult↗
PubMed1989

Short TI inversion-recovery imaging of the liver: pulse-sequence optimization and comparison with spin-echo imaging.

Magnitude-reconstructed short inversion-time (TI) inversion-recovery (IR) sequences have the advantage of reducing the signal of fat while providing additive T1 and T2 contrast. A double-echo short TI IR sequence was implemented to offer different degrees of T1- and T2-dependent image contrast. In 50 consecutive patients with proved liver tumors (30 metastases, 13 hemangiomas, seven other primary liver tumors), images obtained with a double-echo IR sequence at a repetition time (TR) of 1,500 msec, echo time (TE) of 30 and 60 msec, and TI of 80 msec (TR/TE/TI = 1,500/30, 60/80) were compared with those obtained with spin-echo (SE) sequences at a TR of 275 msec and a TE of 14 msec (TR/TE = 275/14) and 2,350/60, 120, 180. Metastases-liver contrast-to-noise ratios were highest at SE 275/14, followed by IR 1,500/30/80 and SE 2,350/180. IR 1,500/30/80 and SE 275/14 sequences consistently showed higher sensitivity for the detection of metastases than T2-weighted SE sequences. Differential diagnosis of benign and malignant lesions was more reliable with T2-weighted SE sequences than T2-weighted short TI IR sequences.

Adult↗
PubMed1989

Forty-millisecond MR imaging of the abdomen at 2.0 T.

The ability of an ultrafast magnetic resonance (MR) imaging technique to provide abdominal MR images free of motion artifacts was studied. Individual T2-weighted transverse MR images were acquired in as little as 40 msec on a whole-body system operating at 2.0 T. Clinical evaluation was undertaken with fat-suppressed images in which only protons of water molecules contributed to image signal intensity. The ultrafast MR images were compared with conventional MR images obtained at 0.6 T. In 22 patients and two healthy volunteers, ultrafast MR images were of diagnostic quality and free of motion artifacts. Images obtained at an echo time (TE) of 30 msec (imaging time, 40 msec) had liver signal-to-noise ratios of 56.3 +/- 22.6 (n = 19). Because of a smaller data matrix, ultrafast MR images had soft-tissue interfaces that were less sharp than those of the highest-quality conventional MR images in which no motion artifacts were present. However, ultrafast MR images demonstrated high T2-dependent soft-tissue contrast, and pathologic and normal anatomies were readily detected with both imaging techniques. This ultrafast imaging technique has significant promise in whole-body MR imaging, in which motion artifacts often degrade image quality.

Abdomen↗
PubMed1989

New universal precaution aspiration tray.

A new tray has been designed for use during procedures involving needles and other sharp objects. The tray includes a foam adhesive pad, marked into 10 sections, into which the sharp objects can be placed point first. After the procedure, the objects can be safely withdrawn by their handles and then discarded. The tray has been used in more than 250 procedures.

Accident Prevention↗
PubMed1989

Infected abdominal tumors: percutaneous catheter drainage.

Sixteen patients underwent percutaneous catheter drainage of infected primary (n = 9) or metastatic (n = 7) abdominal tumors. Twelve of the patients improved clinically, as evidenced by defervescence and decrease or normalization of leukocytosis. Four patients did not respond to catheter drainage and required surgery. Three of the twelve who improved underwent operations for attempts at surgical cure or debulking of tumor volume despite an initial "good" response to percutaneous drainage. Of the nine patients who did not undergo surgery after percutaneous drainage, four underwent catheter removal after 5 weeks of drainage and had no recurrence of infection, two remained alive with the catheter in place up to 8 months and 1 year after drainage, and two died with the catheter in place. One patient had the catheter removed inadvertently after 3 weeks of drainage and had recurrences that required replacement of the catheter until his death. The major differences between drainage of necrotic tumors and drainage of standard abscesses were the need for surgery in the majority of the cases and the fact that patients needed the catheters for continued palliation until their death.

Abdominal Neoplasms↗
PubMed1989

The diagnosis of splenic lymphoma by MR imaging: value of superparamagnetic iron oxide.

This study was designed to evaluate superparamagnetic iron oxide (AMI-25) as a contrast agent for MR to distinguish normal spleens from those diffusely infiltrated by lymphoma. As diffuse splenic involvement lacks visible tumor-tissue boundaries, signal-intensity measurements of spleens were used as a diagnostic criterion in 33 patients (lymphoma, n = 8; benign splenomegaly, n = 5; normal subjects, n = 20). Unenhanced MR images were insensitive (four of eight patients) and nonspecific (20 of 25 patients) in the diagnosis of lymphoma. After injection of superparamagnetic iron oxide (40 mumol Fe/kg), lymphomatous spleens showed a significantly higher signal intensity (p less than .05) than did normal spleens or spleens enlarged by benign disease (hepatic cirrhosis, n = 4; spherocytosis, n = 1). Changes in splenic MR signal intensity unambiguously identified eight of eight lymphomatous spleens and 25 of 25 normal or enlarged spleens that did not contain lymphoma. Phagocytosis of superparamagnetic iron oxide in lymphomatous spleens is reduced because of diffuse displacement of splenic macrophages by lymphoma cells and/or by immunologic suppression of macrophage activity. Our results suggest that superparamagnetic iron oxide (AMI-25) can improve the accuracy of MR imaging in the diagnosis of splenic lymphoma. With further development, this noninvasive technique may reduce the need for diagnostic splenectomy in lymphoma patients.

Contrast Media↗
PubMed1989

Primary liver tumors: diagnosis by MR imaging.

MR features of 153 proved primary liver tumors (95 malignant, 58 benign) in 55 patients with hepatocellular carcinoma (21), cholangiocarcinoma (seven), carcinosarcoma (one), hepatoblastoma (one), hemangioma (16), hepatic adenoma (four), focal nodular hyperplasia (three), leiomyoma (one), and hemangioendothelioma (one) were studied retrospectively to determine which techniques are most reliable for lesion detection and which criteria are most useful for differential diagnosis. MR data were correlated with histologic features such as fatty degeneration, fibrosis, and peritumoral edema. Unlike metastatic cancer, hepatocellular carcinoma was best detected (p less than .01) with T2-weighted pulse sequences. The mean tumor-liver T2 difference was 34.4%, while the mean T1 difference was only 21.8%. A tissue-specific diagnosis of hepatocellular carcinoma was possible in 14 of 21 patients by identification of fatty degeneration of the tumor (eight of 17), tumor capsule (five of 21), and/or vascular invasion (six of 21). MR features of peritumoral edema, present in six of 21 patients with hepatocellular carcinoma and in seven of 25 patients with metastases, were exclusively associated with malignant tumors. The large variation in tissue characteristics (relaxation times and proton density) seen in primary liver tumors necessitates the use of multiple pulse sequences to maximize lesion detection. However, the combined use of T1- and T2-weighted spin-echo and T2-weighted phase-contrast images had the advantage of distinguishing benign from malignant primary liver tumors in 48 of 55 patients in this series.

Adenoma↗
PubMed1989

The sonographic diagnosis of acute gangrenous cholecystitis: importance of the Murphy sign.

The sonographic Murphy sign is defined as the presence of maximal tenderness elicited by direct pressure of the transducer over a sonographically localized gallbladder. The reported prevalence of this sign is more than 95% in patients with acute cholecystitis. In this series of 18 patients with pathologically proved gangrenous cholecystitis, the sonographic Murphy sign was positive in only six (33%). Clinical examination showed a positive Murphy sign in eight patients (44%), diffuse abdominal pain in nine patients (50%), and no pain in one patient (6%). Other sonographic findings included pericholecystic fluid (10), thickening of the gallbladder wall (10), and a dilated gallbladder (five). Our experience suggests that the absence of the Murphy sign increases the possibility of gangrenous cholecystitis in patients with abdominal pain and sonographic findings of cholecystitis.

Abdomen↗
PubMed1989

Imaging of pancreatic neoplasms: comparison of MR and CT.

Thirty-two patients with pathologically proved pancreatic carcinomas or cystadenomas were evaluated with MR images obtained with T1-weighted spin echo (short TR/short TE), inversion recovery, and T2-weighted spin-echo (long TR/long TE) pulse sequences. CT was used as the reference standard to determine the ability of MR to delineate normal and abnormal pancreatic anatomy and thereby to exclude or detect pancreatic malignancy. Short TR/short TE spin-echo sequences were significantly better (p less than .05) than inversion recovery or T2-weighted spin-echo sequences in resolution of both normal and abnormal anatomy. Resolution of pancreatic anatomy correlated (r = .9) with the image signal-to-noise ratio. In seven (22%) of 32 cases, MR visualized pancreatic tumors better than CT did because it showed a signal intensity difference between the tumor and normal pancreatic tissue. Overall, the slight superiority of MR over CT for tumor visualization tended to occur in larger tumors and was not statistically significant. On T1-weighted images, 63% (20 of 32) of pancreatic tumors studied had lower signal intensities than normal pancreatic tissue, whereas on T2-weighted sequences (TE = 60, 120, and 180 msec) only 41% (13 of 32) of tumors had increased signal intensities. Currently available MR imaging techniques offer no significant advantages over CT for evaluating the pancreas for neoplasia.

Adult↗