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J H Sumkin

Publications and source records attributed to J H Sumkin.

16 recordsLinked to original sources
PubMed1998

Computed radiography versus screen-film mammography in detection of simulated microcalcifications: a receiver operating characteristic study based on phantom images.

RATIONALE AND OBJECTIVES: The authors compare a 43-micron computed radiographic system with a mammographic screen-film system for detection of simulated microcalcifications in an observer-performance study. MATERIALS AND METHODS: The task of detecting microcalcifications was simulated by imaging aluminum wire segments (200-500 microns in length; 100, 125, or 150 microns in diameter) that overlapped with tissue background structures produced by beef brisket. A total of 288 such simulations were generated and examined with both computed radiography and conventional screen-film mammography techniques. Computed radiography was performed with high-resolution plates, a 43-micron image reader, and a 43-micron laser film printer. Computed radiographic images were printed with simple contrast enhancement and compared with screen-film images in a receiver operating characteristic study in which experienced readers detected and scored the simulated microcalcifications. Observer performance was quantitated and compared by computing the area under the receiver operating characteristic curve. RESULTS: Although the resolution of the computed radiography system was better than that of commercial systems, it fell short of that of screen-film systems. For the 100-micron microcalcifications, the difference in the average area under the curve was not statistically significant, but it was significant for the larger simulated microcalcifications: the average area under the curve was 0.58 for computed radiography versus 0.76 for screen-film imaging for the 125-micron microcalcifications and 0.83 versus 1.00, respectively, for the 150-micron microcalcifications. CONCLUSION: Observer performance in the detection of small simulated microcalcifications (100-150 microns in diameter) is better with screen-film images than with high-resolution computed radiographic images.

Breast Diseases↗
PubMed1998

Lactating adenoma: US features and literature review.

PURPOSE: To describe the ultrasonographic (US) features of adenoma in a lactating breast. MATERIALS AND METHODS: The US scans of 11 lactating adenomas in nine patients aged 25-36 years examined in 1991-1996 were retrospectively reviewed. In all lesions, diagnoses were cytologically or histologically proved after US-guided fine-needle aspiration biopsy (eight lesions) or core biopsy (three lesions). Six patients were lactating, and three patients were in the third trimester of pregnancy. The US features analyzed were shape, orientation to the chest wall, border characteristics, echogenicity, homogeneity, enhancement or shadowing, and depth within the breast. RESULTS: Most lesions had benign US features such as ovoid shape with the long axis parallel to the chest wall (10 of 11), well-defined margins (eight of 11), homogeneous echotexture (eight of 11), and posterior acoustic enhancement (10 of 11). Four lesions had US features that resembled malignant lesions, such as irregular margins, heterogeneous echotexture, and posterior acoustic shadowing. CONCLUSION: The US features, although generally benign, are not specific. Tissue sampling with fine-needle aspiration biopsy is recommended. Core biopsy is necessary if a diagnosis cannot be made with the aspirate but is not performed initially because of the possibility of milk fistula formation.

Adenoma↗
PubMed1997

Preliminary clinical evaluation of a high-resolution telemammography system.

RATIONALE AND OBJECTIVES: The authors designed, assembled, tested, and clinically evaluated a high-quality, fast, and relatively inexpensive telemammography system. METHODS: The authors designed a telemammography system that uses a high-resolution film digitizer and high data compression (> or = 40:1) to send images over regular telephone lines to a high-resolution laser printer that produces images with the look and feel of the original image and can operate in a hub and spokes mode. The authors then evaluated the system's performance. In a preliminary clinical study, interpretations of the laser-printed system's output of 119 cases were compared with the original interpretations, followed by a review of any clinically significant differences. RESULTS: With the exception of the laser printer, which is a modified off-the-shelf product, all hardware components of the system are commercially available products. The system digitizes (50 microns pixel size), compresses, transmits, receives, decompresses, and prints a 30 MB mammography file in less than 4 minutes. In the clinical study, there were 13 differences (in 13 cases) in the level of concern or recommendations. Seven were found to be clinically insignificant by a third-party review. The remaining six were reviewed by the original interpreter, and three were determined to be significant enough for further action. All were found to result from intra-reader variability rather than differences in visualization of possible abnormalities. CONCLUSIONS: Almost real-time, high-quality telemammography without geographic boundaries is possible with the use of high-level data compression. Telemammography with laser-printed film as the display may make it possible to offer mammographic services in remote locations while using commercially available technology.

Evaluation Studies as Topic↗
PubMed1995

Automated large-core needle biopsy of surgically removed breast lesions: comparison of samples obtained with 14-, 16-, and 18-gauge needles.

PURPOSE: To determine the needle size that would consistently enable the pathologist to correctly diagnose tissue core biopsy specimens. MATERIALS AND METHODS: Fifty-seven surgically removed mass lesions of the breast were sampled with a short-throw automated biopsy gun and an 18-gauge needle first, followed by a 16- and a 14-gauge needle. Samples were evaluated independently by three pathologists, and findings were compared with the final diagnosis made at surgical excision biopsy. RESULTS: The sensitivity for the diagnosis of all 26 malignant lesions was 100%, 92%, and 65% for biopsy samples obtained with 14-, 16-, and 18-gauge needles, respectively. Specificity for malignancy was 100% for all three needle sizes. All of the benign diseases were correctly diagnosed in samples obtained with all three size needles except for two samples that did not survive processing. CONCLUSION: Biopsy samples obtained with a 14-gauge needle provide the most accurate diagnosis, which correlates with the diagnosis made with the surgical excision biopsy technique.

Automation↗
PubMed1994

Diagnostic reading session: temporal patterns and case-order effects.

The authors analyzed receiver-operating-characteristic studies to determine temporal patterns and performance as a function of the elapsed time in a reading session. Nineteen radiologists each read as many as 300 chest images with use of seven different display modalities, including conventional and laser-printed film and high-resolution soft display. With a computerized reporting system, the ratio of observers' interpretation rates (time to diagnosis) were recorded for the last five and 10 compared with the first five and 10 of 30-40 cases seen in sessions lasting 45-110 minutes. Observers tended to accelerate their interpretation as the sessions progressed by an average of 15% (P < .001). The acceleration was consistent for all readers (both fast and slow) with a variety of display modes under the nonrestricted time environment.

Humans↗
PubMed1993

Contemporary radiologic percutaneous abscess drainage in the pelvis.

In summary, PAD of pelvic abscesses is an established radiologic procedure. The procedure has gained wide acceptance as an adjunct in the management of patients with pelvic abscess. The procedure involves minimal trauma, is well tolerated, and produces early relief of symptoms. In many instances, it may shorten the length of the hospital stay, reduce costs, and often eliminate the need for surgical intervention. In selected patients, PAD may serve as a temporizing measure in a critically ill or endstage patient. Initial results of PAD treatment of TOA are encouraging, suggesting that this procedure, just as elsewhere in the abdomen, is safe and effective, but larger series are required and long-term follow-up is necessary for evaluation of the cure rate, rate of recurrence, and possible complications.

Abdominal Neoplasms↗
PubMed1991

CT appearance of the Roux limb following choledochojejunostomy in liver transplantation.

Choledochojejunostomy in Roux-en-Y is a frequent form of biliary reconstruction in liver transplants. On computed tomography (CT), fluid in the Roux limb may simulate a fluid collection. We studied the CT appearance of the Roux jejunal limb in 25 normal and complicated liver transplant patients. The Roux limb was identified in 21 (84%) of 25 cases. Most frequently useful features were characteristic location, continuous tubular appearance, biliary stent, "bull's eye" appearance, and gas in the loop. Two of 18 normal Roux loops were initially suspected of being abscesses and one gas-containing abscess was initially mistaken for the Roux limb. In five of seven patients with complications (four abscesses, two bile leaks, one anastomotic hemorrhage), identification of the Roux limb was possible and was useful in interpreting CT scans. Knowledge of the appearance of the normal and abnormal Roux limb is essential for proper interpretation of CT scans in liver transplant patients.

Abscess↗
PubMed1991

US-guided venipuncture for venography in the edematous leg.

A technique for sonographic-guided venipuncture was developed especially for venography made difficult by gross leg edema. Five patients were evaluated in whom venography had been attempted but was initially unsuccessful because of difficult venous access. All five underwent successful venipuncture after sonographic localization of a vein. Ultrasound-guided venipuncture is simple and useful when venous access by palpation is difficult.

Bloodletting↗
PubMed1990

The effect of clinical history on chest radiograph interpretations in a PACS environment.

The effect that accompanying patient information has on diagnostic accuracy in radiologic interpretation has been studied by many researchers but remains a matter of contention. Experiments in the past emphasized the chest film because this procedure is the one done most frequently in radiology. However, with the increasing importance of digital imaging, the role of patient history in these procedures should be assessed. The use of a model computerized patient history in the interpretation of digitized chest images that were displayed on a high-resolution workstation was studied. Two hundred forty-seven selected posteroanterior chest images that indicated disease and that indicated no disease were interpreted in random sequence by five board-certified radiologists, with and without accompanying patient histories. Readers were prompted by the response forms to evaluate images for the possible occurrence of interstitial diseases, nodules, or pneumothorax. No significant differences (P = .05) in the detection of these abnormalities were noted between case readings with and without history for any of the radiologists or for the group as a whole. However, this methodology reflects a direct interpretation approach. The results of this study may not necessarily be applicable to individual prompts, different imaging procedures, or other abnormalities.

Hospital Information Systems↗
PubMed1989

Liver transplant rejection: value of the resistive index in Doppler US of hepatic arteries.

The authors prospectively evaluated the accuracy of the resistive index (RI) in Doppler ultrasound (US) for the detection of the increased vascular resistance that theoretically occurs with acute liver transplant rejection. RIs were calculated for the proximal hepatic artery and a more distal hepatic artery branch in 67 liver transplant recipients. Biopsies were performed within 24 hours of transplantation, with no intervening therapy. Examination of biopsy specimens by a single pathologist revealed findings of no, minimal, or moderate to severe rejection. RIs in hepatic arteries showed no significant differences among the three pathologic groups. No correlation was found between the RI and improved or worsened rejection in 11 patients who underwent biopsy and US more than once. RIs in hepatic arteries are of no value in the prediction of liver transplant rejection.

Acute Disease↗
PubMed1989

Periportal low-attenuation areas on CT: value as evidence of liver transplant rejection.

CT scans of liver transplants may show periportal areas that are lower in attenuation than adjacent portal veins and liver. These areas appear as low-density rims that surround or parallel the portal vein and its intrahepatic branches as well as the immediate subhepatic portal area. In order to determine the value of periportal low attenuation as an indicator of rejection, we reviewed the CT scans of 37 liver transplant patients with biopsy evidence of either acute rejection (12 patients) or nonspecific change without rejection (25 patients). Low-attenuation areas around peripheral portal branches were identified in six of 12 patients with rejection and in four of 25 patients with nonspecific change (sensitivity, 50%; specificity, 84%; accuracy, 73%). The correlation between peripheral periportal low attenuation and rejection was statistically significant (p less than .05). Periportal low attenuation in a central location was seen in eight of 12 patients with acute rejection and in 14 of 25 patients with nonspecific change (sensitivity, 67%; specificity, 44%; accuracy, 51%). The correlation was not statistically significant. Low-attenuation areas were evident on scans obtained either with or without IV contrast enhancement. Periportal low-attenuation areas are commonly seen on CT scans of liver transplants. Peripheral areas correlate with acute rejection, but other factors probably contribute to their occurrence. Central areas do not correlate with acute rejection. Low sensitivity and relatively low accuracy limit the usefulness of peripheral periportal low attenuation as a sign of acute liver allograft rejection.

Adult↗
PubMed1988

Pseudoaneurysms complicating organ transplantation: roles of CT, duplex sonography, and angiography.

In a retrospective study of proved pseudoaneurysms (PAs) in 15 patients with transplanted organs (11 liver, three kidney, one pancreas), the results of computed tomography (CT), duplex sonography, and angiography were reviewed. Of the 15 cases of PA, eight occurred at the arterial anastomosis and seven were nonanastomotic. Three of the eight anastomotic PAs were caused by infection. Of the seven nonanastomotic PAs, four were caused by percutaneous biopsy, two were caused by infection, and one was of undetermined cause. In nine (60%) of the 15 patients the PAs were incidentally detected at imaging studies performed for other reasons. Diagnosis requires a high degree of suspicion. CT was performed in nine cases and duplex sonography in ten. The diagnosis of PA was made with CT in six (67%) patients and with duplex sonography in five (50%). CT and duplex sonography could not enable diagnosis when the PA was small, when the arterial anastomosis was not included in the field of study, or when enhancement with intravenously administered contract material was suboptimal. Angiography depicted the PAs in all 15 patients. In three liver transplant recipients with gastrointestinal tract bleeding, the causative PAs were detected only with angiography.

Adult↗
PubMed1988

Duplex sonography of hepatic artery thrombosis after liver transplantation.

When hepatic artery thrombosis occurs after liver transplantation, another transplantation is required to ensure the patient's survival. Because of the importance of establishing this diagnosis, we reviewed the results of duplex sonography in 37 angiographically or surgically proved cases of hepatic artery thrombosis after liver transplantation. There were 20 children and 17 adults. Ten of the 20 children had angiographically documented hepatopetal arterial collaterals. Such collaterals were not seen in the adult patients. This subset of patients was evaluated separately to determine if intrahepatic arterial blood flow reestablished by collaterals after hepatic artery thrombosis was a cause of false-negative Doppler studies. Thirty-four (92%) of the 37 cases of hepatic artery thrombosis were correctly identified by Doppler. A Doppler pulse was not identified in any of the children with arterial collaterals. We conclude that duplex sonography is sensitive in detecting hepatic artery thrombosis after liver transplantation. Furthermore, the presence of blood flow in hepatopetal arterial collaterals does not cause false-negative examinations.

Adolescent↗