Elastography in the evaluation of liver allograft

Elastography is an established technique in the evaluation of chronic liver diseases. While there is a large clinical experience and data available regarding the performance of elastography in native liver, elastography experience with liver grafts is limited and still growing. Both ultrasound-based elastography techniques and MR Elastography (MRE) are useful in the assessment of liver fibrosis in liver transplants. Technical modifications for performing elastography will be required for optimum evaluation of the graft. In general, caution needs to be exercised regarding the use of elastography immediately following transplantation as post-operative changes, perioperative conditions/complications, inflammation, and rejection can cause increased stiffness in the graft. In the follow-up, detection of increased stiffness with elastography is useful for predicting development of fibrosis in the graft. Adjunctive MRI or ultrasound with Doppler also provides comprehensive evaluation of anatomy, vascular anastomosis and patency, biliary tree, and stiffness for fibrosis. In this review, we provide a brief overview of elastography techniques available followed by the literature review of elastography in the evaluation of grafts and illustration with clinical examples.

An invasive cleavage assay for direct quantitation of specific RNAs

RNA quantitation is becoming increasingly important in basic, pharmaceutical, and clinical research. For example, quantitation of viral RNAs can predict disease progression and therapeutic efficacy. Likewise, gene expression analysis of diseased versus normal, or untreated versus treated, tissue can identify relevant biological responses or assess the effects of pharmacological agents. As the focus of the Human Genome Project moves toward gene expression analysis, the field will require a flexible RNA analysis technology that can quantitatively monitor multiple forms of alternatively transcribed and/or processed RNAs (refs 3,4). We have applied the principles of invasive cleavage and engineered an improved 5'-nuclease to develop an isothermal, fluorescence resonance energy transfer (FRET)-based signal amplification method for detecting RNA in both total RNA and cell lysate samples. This detection format, termed the RNA invasive cleavage assay, obviates the need for target amplification or additional enzymatic signal enhancement. In this report, we describe the assay and present data demonstrating its capabilities for sensitive (<100 copies per reaction), specific (discrimination of 95% homologous sequences, 1 in > or =20,000), and quantitative (1.2-fold changes in RNA levels) detection of unamplified RNA in both single- and biplex-reaction formats.

Hepatic enhancement analysis in children using smart prep monitoring for 2 : 1 pitch helical scanning

PURPOSE

To analyze hepatic enhancement by using Smart Prep protocols appropriate for children of different weight groups and 2:1 pitch helical CT imaging as the investigative tools.

PATIENTS AND METHODS

A group of 55 children ranging in weight between 20 and 180 lbs underwent 67 contrast-enhanced abdominal helical CT examinations using Smart Prep (GE Medical Systems, Milwaukee, Wisc.). Of these studies, 21 (31 %) were excluded because of failure to follow the prescribed Smart Prep protocols. Smart Prep protocols were established for nine different weight groups. Scan delay, aorta and liver time to peak, and liver enhancement over baseline were recorded.

RESULTS

Optimal abdominal CT studies with adequate contrast enhancement of hepatic and portal veins were obtained in 46 patients. There was no significant difference in the time between peak aortic and the liver enhancement among different weight groups (mean time 12.0 +/- 7.1 s for all children). However, the mean hepatic enhancement over baseline in children weighing < 30 lbs was below 50 Hounsfield units (HU) compared to the rest of the children who had mean hepatic enhancement of > 50 HU.

CONCLUSION

Two-thirds of the Smart Prep protocols were successfully implemented, and all of these resulted in good contrast enhancement of hepatic and portal veins. Optimal mean liver enhancement (> 50 HU) was seen in children >/= 30 lbs. Children < 30 lbs had mean liver enhancement of 33 HU +/- 7.2 above the baseline likely caused by contrast dose.

"The heart still beat, but the brain doesn't answer". Perception and experience of old-age dementia in the Milwaukee Hmong community

The purpose of this exploratory and descriptive study was to examine old-age dementia in the Hmong community of Milwaukee, Wisconsin. Formal and informal Hmong leaders were interviewed to determine the prevalence of dementia in the Hmong community and how it is perceived and experienced. Interviews revealed few cases of dementia among the Hmong. Dementia was perceived as a natural part of the life cycle, rather than as a devastating disease that robs individuals of their autonomy. Treatment is not sought for dementia. Some of the common manifestations of dementia, such as wandering and combativeness, were rare or non-existent in the Hmong community. Individuals with dementia are cared for in their sons' homes. Nursing home placement in advanced dementia was only acceptable if sanctioned by the entire extended family. Further research on the Hmong perception of and experience with dementia needs to be conducted in other Hmong communities to validate the generalizability of these results.

Assessing the resectability of pancreatic carcinoma: the value of reinterpreting abdominal CT performed at other institutions

OBJECTIVE

The purpose of this study was to determine the value of reinterpreting abdominal CT performed at other institutions when assessing the resectability of pancreatic carcinoma.

MATERIALS AND METHODS

Fifty-three patients (30 men, 23 women; mean age, 62 years) referred to our tertiary care institution with newly diagnosed pancreatic carcinoma had formally reinterpreted abdominal CT scans and available initial reports. CT was performed at community hospitals (n = 47), university hospitals (n = 4), an outpatient clinic (n = 1), and an imaging center (n = 1); reinterpretation was performed by university radiologists with subspecialty expertise in abdominal imaging. On the basis of the initial and reinterpretation reports, the patients were categorized as having resectable or nonresectable disease. Medicare reimbursement rates were assessed.

RESULTS

The initial and reinterpretation reports agreed in 36 (68%) of the 53 patients, with the disease of 16 patients considered resectable and 20 unresectable by both reports. In 17 patients (32%), we found discrepancies between the initial and the reinterpretation reports. All discrepancies involved the initial report indicating resectability and the reinterpretation report consistent with nonresectable disease. Discrepancies were resolved by findings at surgery (n = 9), percutaneous biopsy (n = 3), dedicated pancreatic CT (n = 3), dedicated liver CT (n = 1), and follow-up abdominal CT (n = 1); the reinterpretation reports were correct in 16 (94%) of 17 patients. Reimbursement for outside CT reinterpretation, repeated abdominal CT, and an exploratory laparotomy were estimated at $46.45, $414.47, and $16,996.44, respectively.

CONCLUSION

Reinterpretation of outside abdominal CT was valuable for determining pancreatic carcinoma resectability and inexpensive when compared with repeating the CT examination or performing an exploratory laparotomy.

Transthoracic fine-needle aspiration cytology of inflammatory pseudotumor, fibrohistiocytic type: a case report with immunohistochemical studies

Inflammatory pseudotumor, fibrohistiocytic type, also called benign fibrous histiocytoma, is a rare reactive entity usually found incidentally on routine chest roentgenography. We present a case of inflammatory pseudotumor, fibrohistiocytic type, initially diagnosed by fine-needle aspiration (FNA) cytology in a 39-yr-old woman with a history of breast carcinoma. Cytomorphologic characteristics were confirmed by a cell block examination and immunohistochemical findings. The differential diagnoses of the fine-needle aspiration cytology of this type of inflammatory pseudotumor are discussed.

Normal myeloid development requires both the glutamine-rich transactivation domain and the PEST region of transcription factor PU.1 but not the potent acidic transactivation domain

Gene targeting of transcription factor PU.1 results in an early block to fetal hematopoiesis, with no detectable lymphoid or myeloid cells produced in mouse embryos. Furthermore, PU.1(-/-) embryonic stem (ES) cells fail to differentiate into Mac-1(+) and F4/80(+) macrophages in vitro. We have previously shown that a PU.1 transgene under the control of its own promoter restores the ability of PU. 1(-/-) ES cells to differentiate into macrophages. In this study, we take advantage of our PU.1(-/-) ES cell rescue system to genetically test which previously identified PU.1 functional domains are necessary for the development of mature macrophages. PU.1 functional domains include multiple N-terminal acidic and glutamine-rich transactivation domains, a PEST domain, several serine phosphorylation sites, and a C-terminal Ets DNA binding domain, all delineated and characterized by using standard biochemical and transactivational assays. By using the production of mature macrophages as a functional readout in our assay system, we have established that the glutamine-rich transactivation domain, a portion of the PEST domain, and the DNA binding domain are required for myelopoiesis. Deletion of three acidic domains, which exhibit potent transactivation potential in vitro, had no effect on the ability of PU.1 to promote macrophage development. Furthermore, mutagenesis of four independent sites of serine phosphorylation also had no effect on myelopoiesis. Collectively, our results indicate that PU.1 interacts with important regulatory proteins during macrophage development via the glutamine-rich and PEST domains. The PU.1(-/-) ES cell rescue system represents a powerful, in vitro strategy to functionally map domains of PU.1 essential for normal hematopoiesis and the generation of mature macrophages.

Complications of prostate cryosurgery: CT findings in three patients

We present the computed tomographic (CT) findings of complications of prostate cryosurgery in three patients. One patient had injury to the bladder base and rectum, which resulted in ureteral obstruction and vesicorectal fistula. The other two patients had urethral injuries. All three patients had CT evidence of prostate necrosis. If utilization of prostate cryosurgery increases, complications will be encountered more frequently on imaging studies.

Prostate carcinoma: transrectal US after cryosurgical ablation

PURPOSE

To characterize the transrectal ultrasound (US) morphology of the prostate after cryosurgical ablation and correlate these findings with the detection of residual tumor at transrectal US-directed biopsy.

MATERIALS AND METHODS

Findings from 24 transrectal US examinations in 15 patients (age range, 63-75 years) who had undergone cryosurgical ablation of the prostate were reviewed. Prospective identification of focal lesions with transrectal US and retrospective review of US prostate morphology were correlated with clinical data and transrectal US-directed biopsy results.

RESULTS

Identification of a focal lesion with transrectal US yielded a sensitivity of 13%, specificity of 69%, positive predictive value of 17%, and negative predictive value of 61% for the detection of residual carcinoma. US prostate morphology was variable and distorted in the majority of cases.

CONCLUSION

Identification of focal lesions with transrectal US is not a reliable criterion for the detection of residual tumor in the prostate after cryosurgical ablation. Systematic biopsy should not be deferred owing to lack of transrectal US identification of focal abnormalities in patients with appropriate clinical indications.

PU.1 functions in a cell-autonomous manner to control the differentiation of multipotential lymphoid-myeloid progenitors

Transcription factor PU.1 is required for the development of lymphoid and myeloid progenitors during fetal hematopoiesis. By generating chimeric animals using PU.1-/- ES cells or PU.1(-/-) hematopoietic progenitors, we demonstrate that PU.1 functions in an exclusively cell-autonomous manner to regulate the development of the lymphoid-myeloid system. Multipotential lymphoid-myeloid progenitors (AA4.1+, Lin-) are significantly reduced in PU.1(-/-) embryos and fail to differentiate into B lymphoid or myeloid cells in vitro. These results suggest that the lymphoid and myeloid lineages develop in the fetal liver from a common hematopoietic progenitor not shared with erythrocytes and megakaryocytes. Finally, the Ikaros gene is expressed in PU.1 mutant embryos, suggesting that PU.1 and Ikaros are independently required for specification of embryonic lymphoid cell fates.

Transcription factor GATA-3 is required for development of the T-cell lineage

THE zinc-finger transcription factor GATA-3 is expressed in haematopoietic cells and in the developing kidney and nervous system. Within the haematopoietic lineages, expression of GATA-3 is restricted to thymocytes and T cells. Functionally important GATA-3 binding sites have been identified in multiple T-cell-specific genes. Mice containing homozygous null mutations of the GATA-3 gene die on embryonic day 12, precluding a detailed assessment of the role of GATA-3 in haematopoietic development. Here we have used murine embryonic stem (ES) cells containing homozygous mutations in the GATA-3 gene (GATA-3(-/-)) in conjunction with the RAG-2(-/-) (ref. 10) and C57BL/6 complementation systems to study the role of GATA-3 in mammalian haematopoiesis. Our results show that GATA-3(-/-) ES cells can contribute to the development of the mature erythroid, myelomonocytic and B-cell lineages, but fail to give rise to thymocytes or mature peripheral T cells. The differentiation of GATA-3(-/-) T cells is blocked at or before the earliest double-negative (CD4-/CD8-) stage of thymocyte development, such that the GATA-3(-/-) ES cells are unable to contribute measurably to the double-negative thymocyte population. These findings suggest that GATA-3 is an essential and specific regulator of early thymocyte development.

Evaluation of image quality using 1 : 1 pitch and 1.5 : 1 pitch helical CT in children: a comparative study

OBJECTIVE

The objective of this study was to compare the quality of 1 : 1 and 1.5 : 1 pitch helical contrast-enhanced thoracic and abdominal CT images in children who cannot cooperate for breath holding.

MATERIALS AND METHODS

This is a retrospective study of 33 contrast-enhanced CT examinations in 11 children of 0-4 years of age. All children had an initial CT study using 1 : 1 pitch helical scanning followed over the next 6-36 months by one to four CT examinations with 1.5 : 1 pitch. Radiation dose with the two techniques was measured with a pencil ionization chamber.

RESULTS

The two techniques provided comparable overall image quality. There was 33 % less radiation dose with 1.5 : 1 pitch helical scanning.

CONCLUSION

The 1.5 : 1 pitch helical CT provides comparable quality images and a smaller radiation dose than 1 : 1 pitch in examining children aged 0-4 years.

Polyorchidism and rete testis adenoma: ultrasound and MR findings

Polyorchidism is an uncommon congenital anomaly. It is associated with an increased frequency of testicular malignancy, cryptorchidism, inguinal hernia, and torsion. Sonography may be used to confirm the clinically suspected diagnosis. We present a case of polyorchidism in which a rete testis adenoma was present in one of the testicles. Sonographic and magnetic resonance findings are illustrated.

Assessment of a technology that permits individualized scan delays on helical hepatic CT: a technique to improve efficiency in use of contrast material

OBJECTIVE

We performed this study to assess the usefulness of a computer automated scan technology (CAST) for individualizing scan delay during helical CT to improve the efficiency of hepatic enhancement.

SUBJECTS AND METHODS

We prospectively evaluated 183 patients who were randomized into five groups. Control patients received 100 or 150 ml of contrast material (320 mg I/ml) with a 60-sec delay between contrast injection at 3 ml/sec and scanning. CAST patients received 100, 125, or 150 ml. In our latter groups we used an hepatic enhancement threshold of 50 H over baseline to determine the optimum delay between contrast injection and scanning. For the intergroup comparisons, we measured the liver on baseline and enhanced helical CT scans at the upper, mid, and lower levels of the liver.

RESULTS

The mean enhancement in patients who received 150 ml of contrast material was 70.7 +/- 19.4 H for the control group and 81.0 +/- 17.5 H for the CAST group (p < .05). Hepatic enhancement above 50 H was achieved in 84% of the control subjects compared with 100% of CAST subjects; more than 60 H hepatic enhancement was achieved in 73% of control subjects and in 89% of CAST subjects. The use of CAST software with 125-ml contrast doses provided enhancement equivalent to that of control subjects who received 150 ml of contrast material (mean enhancement in CAST subjects, 70.3 +/- 15.4 H). Enhancement above 50 H was reached in 98% of CAST and 84% of control patients. With 100 ml of contrast material, 24% of patients failed to initiate CAST, resulting in enhancement similar to control patients (CAST, 54.2 +/- 11.4 H; controls, 56.9 +/- 15.2 H).

CONCLUSION

Using a contrast dose of 150 ml, CAST provided significantly increased hepatic enhancement than that achieved in control subjects with less variability. For equivalent hepatic enhancement, contrast doses could be decreased by 25 ml using CAST technology because it provides individualized scan delays.

Helical computed tomography at 1.5:1 pitch reconstructed at 15-mm and 7-mm intervals for examination of patients with suspected metastatic disease

OBJECTIVE

To document the need for overlapped reconstruction when using helical computed tomography (CT) software that reconstructs 10-mm-collimation, 1.5:1-pitch images at 15-mm intervals in follow-up examination of patients with suspected metastatic disease.

PATIENTS AND METHODS

Forty consecutive patients with known or suspected metastatic disease were examined with helical CT at 10-mm collimation and 1.5:1 pitch. The studies were examinations of the chest, abdomen and pelvis; the chest and abdomen; or the abdomen and pelvis. Two image sets, one prospectively reconstructed at 15-mm intervals and the other retrospectively reconstructed at 7-mm intervals, were independently reviewed by three radiologists, and the number, size and location of lesions were documented. Differences in interpretation were resolved by consensus. The lesions detected on the two sets of images were classified according to lesion size and location, and the results were analysed by multivariate analysis of variance with repeated measures.

RESULTS

Images reconstructed at 7-mm intervals revealed a total of 436 lesions, 127 (41%) more than were revealed by images reconstructed at 15-mm intervals. The number of lesions less than 1 cm in diameter that were visible in the two sets of images was significantly different (p = 0.018). However, there was no significant difference between the two sets of images in terms of lesion location.

CONCLUSION

Metastatic lesions may be missed by helical CT at 1.5:1 pitch if overlapped reconstruction is not performed.

PU. 1 is not essential for early myeloid gene expression but is required for terminal myeloid differentiation

We have previously shown using gene targeting that PU.1 is essential for the development of lymphoid and myeloid lineages during fetal liver hematopoiesis. We now show that PU.1 is required for the maturation of yolk sac-derived myeloid progenitors and for the differentiation of ES cells into macrophages. The role of PU.1 in regulating target genes, thought to be critical in the development of monocytes and granulocytes, has been analyzed. Early genes such as GM-CSFR, G-CSFR, and myeloperoxidase are expressed in PU.1-/- embryos and differentiated PU.1-/- ES cells. However, the expression of genes associated with terminal myeloid differentiation (CD11b, CD64, and M-CSFR) is eliminated in differentiated PU.1-/- ES cells. Development of macrophages is restored with the introduction of a PU.1 cDNA regulated by its own promoter. The PU.1-/- ES cells represent an important model for analyzing myeloid cell development.

Urologic applications of multiplanar and three-dimensional computed tomography

The introduction of helical computed tomography (CT) has resulted in improved quality of multiplanar reformations and three-dimensional reconstructions in the chest and abdomen and has made CT angiography a clinical reality. These imaging techniques are useful for evaluating the urinary tract, adding a new dimension to its display, resulting in improved diagnosis of renal and perirenal disease. This article reviews the indications and techniques utilized for multiplanar and three-dimensional CT for urology. The advantages and limitations are discussed, and normal and pathologic findings in the urinary tract illustrated.

Sonography of the umbilical cord

Knowledge of the development, normal sonographic appearance, and potential abnormalities of the umbilical cord is important in fetal assessment. The umbilical cord can be visualized throughout most of gestation and is detectable sonographically soon after visualization of the fetal pole. The normal umbilical cord is 50-60 cm long and may coil as many as 40 times, usually to the left. Abnormalities in umbilical cord size, degree of coiling, attachment, and position can have important implications for the outcome of the pregnancy. Structural abnormalities of the umbilical cord such as single umbilical artery, knots, cysts, and tumors may be associated with fetal distress or malformations. Color Doppler ultrasound (US) is useful in the identification and evaluation of structural abnormalities of the cord. By allowing measurement of blood flow velocity in the umbilical artery, duplex Doppler US may provide additional information in the evaluation of intrauterine growth retardation and twin-twin transfusion syndrome.

The variation of inguinal lymph node depth in adult women and its importance in planning elective irradiation for vulvar cancer

BACKGROUND

The Gynecologic Oncology Group (GOG) protocol #88 reported an 18.5% failure in inguinal lymph nodes of patients with vulvar cancer whose groins were treated with radiation alone. This high failure rate may be due to the study design.

METHODS

In this study, the depths of inguinal lymph nodes were evaluated with computed tomography (CT) scans in 100 adult women without inguinal adenopathy or prior inguinal surgery. The dose that would have been delivered to the inguinal lymph nodes of these patients was determined using isodose curves constructed according to the guidelines in GOG protocol #88.

RESULTS

Only 18% of women had all inguinal lymph nodes measured at a depth of 3 cm or less.

CONCLUSIONS

More than one-half of all women in this study would have received less than 60% of the prescribed radiation dose because their inguinal lymph nodes were deeper than 5 cm, if the depth of their inguinal lymph nodes had not been measured before therapy.

Directed and random biopsies of the prostate: indications based on combined results of transrectal sonography and prostate-specific antigen density determinations

OBJECTIVE

We studied the usefulness of transrectal sonography, prostate-specific antigen levels, and prostate-specific antigen density as indications for directed and random biopsies of the prostate in patients with possible prostatic cancer.

MATERIALS AND METHODS

A total of 141 patients with increased levels of prostate-specific antigen or abnormal findings on digital rectal examination had transrectal sonography of the prostate and determination of prostate-specific antigen density. Through sonographic visualization, all patients had biopsies of possible cancerous lesions and random biopsies of regions of the prostate that appeared normal. Histologic results were correlated with sonographic findings and determinations of prostate-specific antigen levels and prostate-specific antigen density.

RESULTS

Adenocarcinoma was detected in 40 (28%) of the 141 patients. Transrectal sonography showed an abnormality that was determined by directed biopsy to be a carcinoma in 27 (68%) of the 40 patients. Transrectal sonography showed no carcinoma in 13 patients (32%) for whom random biopsy revealed a tumor. The sensitivity of sonography was 68%, and the specificity was 49%. The combination of sonographic findings suggestive of cancer and increased prostate-specific antigen density had a sensitivity of 75% and a specificity of 75%; we calculated a sensitivity of 72% and a specificity of 56% for the combination of sonographic findings suggestive of tumor and increased levels of prostate-specific antigen. Thirty-nine (97%) of 40 patients with cancer had either sonographic findings suggestive of tumor or increased prostate-specific antigen density, and one (3%) had no evidence of tumor on sonography and a normal prostate-specific antigen density.

CONCLUSION

Directed and random sonographic biopsies of the prostate are indicated in patients with sonographic findings suggestive of tumor and increased prostate-specific antigen density and in patients with abnormal sonographic findings and normal prostate-specific antigen density. Random biopsies are indicated in patients with normal sonographic findings and increased prostate-specific antigen density. In our series, random biopsies were not indicated in 25 of 26 patients with normal sonographic findings and normal prostate-specific antigen density. Further research on the need for random biopsies when there are no sonographic abnormalities and when prostate-specific antigen densities are not elevated is warranted.

CT of the chest and abdomen in patients on mechanical pulmonary ventilators: quality of images made at 0.6 vs 1.0 sec

OBJECTIVE

Chest and abdominal CT scans using 1.0-sec scan times are often limited by motion in patients who are unable to hold their breath. With our scanner we can obtain images in 0.6 sec (partial scan) that use data from 225 degrees instead of the 360 degrees used for 1.0-sec scans. The purpose of this study was to assess whether the quality of images of the chest and abdomen in patients on mechanical pulmonary ventilators who could not breath-hold could be improved if images were taken using a scan time of 0.6 sec rather than 1.0 sec.

MATERIALS AND METHODS

Thirty patients who were being treated with mechanical pulmonary ventilation with indications for chest or abdominal CT or both were scanned with a scan time of 1.0 sec. At the end of the examination, additional 0.6-sec images were taken at three or four levels. Images obtained with these two scan times were filmed at similar levels and windows, and anatomically matched levels were compared. The images were masked and independently evaluated by three radiologists for motion, noise, artifact, and overall image quality. Each parameter was rated using a scale of 1 to 4. Using Kendall's tau correlation, there was no significant difference between the radiologists in the grading of individual parameters or of overall image quality. Therefore, the average of the scores of the three radiologists was used. Statistical analysis was done using repeated measures multivariate analysis of variance.

RESULTS

Images obtained in 0.6 sec had significantly less motion (p < .001) but more noise (p < .001) than those obtained in 1.0 sec. We found no statistically significant difference in artifacts between the two scan times. Overall image quality was judged to be significantly better on scans obtained in 0.6 sec than on scans obtained at 1.0 sec (p < .001), in spite of the greater noise on 0.6-sec images. The higher quality of 0.6-sec images was most noticeable for lung window settings.

CONCLUSION

Our results indicate that scans taken in 0.6 sec (partial scans) provide better quality images than those obtained in 1.0 sec in patients being treated with mechanical pulmonary ventilation who cannot breath-hold. This technique may be useful not only in this population but in all patients who are unable to cooperate with breath-holding instructions.

The persistent computed tomography nephrogram: its significance in the diagnosis of contrast-associated nephrotoxicity

A study was undertaken to find out if there is a quantitative relationship between the development of contrast-associated nephrotoxicity (CAN) and the mean renal cortical attenuation (RCA) as seen on computed tomography (CT) examination of the kidneys 24 hours after injection of contrast medium. 96 patients undergoing aortography were selected, who were considered "high risk" either because of the presence of a baseline serum creatinine (Cr) of 123.76 mumol l-1 (1.4 mg dl-1) or higher, or who were 73 or older with or without elevated creatinine levels. A CT study of the kidneys at approximately 24 h was correlated with baseline serum creatinine as well as 24 h Cr (48-72 h Cr when available). Medical history and medications were recorded. Eight of 96 patients had RCA of 108-236 HU at 24 h CT and all developed significant CAN of varying degree; 3/96 had RCA ranging from 48 to 67 HU and had transient CAN; two other patients with RCA of 67-90 HU developed CAN; and there was increased incidence of CAN in patients: (a) with pre-existing renal insufficiency; (b) with diabetes with renal insufficiency; (c) on diuretics; (d) who were older; and (e) had a unilateral atrophic kidney. It was concluded that a 24 h CT study evaluating the RCA had better predictive value for the development of CAN than a 24 h creatinine level.

Inflammatory pseudotumor of the liver: appearance on MRI

Inflammatory pseudotumor of the liver is a rare entity; fewer than 50 cases have been reported in the world literature. Its appearance on both computerized tomography (CT) and ultrasound have been previously described. To our knowledge, this is the first report of its appearance on magnetic resonance imaging (MRI). The lesion demonstrated increased signal intensity on T-1 and T-2 spin-echo and inversion recovery (STIR) sequences in relationship to normal liver. The signal characteristics, however, were nonspecific and diagnosis required biopsy confirmation. There was spontaneous resolution with conservative management, and this was documented on follow-up CT and MRI.

Radical prostatectomy: transrectal sonographic evaluation to assess for local recurrence

PURPOSE

To determine sonographic features associated with locally recurrent or residual tumor.

MATERIALS AND METHODS

Twenty-three transcretal ultrasound (TRUS) studies were performed in 21 patients with suspected recurrent prostatic carcinoma after prostatectomy. The original prospective TRUS reports were reviewed, followed by blinded review, and the findings were compared with biopsy results.

RESULTS

A discrete perianastomotic mass was identified prospectively in eight (73%) of 11 patients with positive biopsy results and in two (17%) of 12 with negative results; no mass was identified in the remaining patients. At preliminary retrospective review, the echogenic retroanastomotic fat plane was not intact in 10 (91%) of 11 patients with positive biopsy results and in two (17%) of 12 with negative results; it was intact in the remaining patients.

CONCLUSION

Sonographic visualization of a mass in the prostate bed or loss of integrity of the retroanastomotic fat plane is strongly correlated with finding recurrent or residual tumor in this location. TRUS in evaluation of the source of postoperative evaluation of prostate-specific antigen levels warrants further investigation.

Computed tomography diagnosis of partial anomalous pulmonary venous drainage

A case of the rarely occurring partial anomalous pulmonary venous drainage of the right upper lobe into the azygos arch is presented. Computed tomography (CT) clearly demonstrated the abnormal vessel coursing through the right upper lobe and draining into the azygos arch.

Pancreatic plasmacytomas in a patient with multiple myeloma: CT and ultrasound findings

Extramedullary plasmacytomas are an unusual manifestation of multiple myeloma. They occur most frequently in tissues or organs rich in reticulo-endothelial cells. Pancreatic plasmacytomas are rare, with only a few case reports in the literature. We present the ultrasound (US) and computed tomographic (CT) findings of two pancreatic plasmacytomas in a patient with multiple myeloma.

MR imaging of the brachial plexus

The brachial plexus is difficult to evaluate with conventional radiologic techniques, including CT. However, it is well shown by MR imaging, which has direct multiplanar imaging capability and superior soft-tissue resolution [1-4]. We present our technique for evaluating the brachial plexus, discuss the anatomy, and illustrate normal and abnormal findings.

CT appearance of calcified tumor thrombus in the inferior vena cava

We report the unusual occurrence of calcified tumor thrombus in the inferior vena cava (IVC) in a patient with renal cell carcinoma diagnosed by computed tomography (CT).

Actinomycosis of the retroperitoneum and an extremity: CT features

A patient presenting with thigh and flank masses and back pain for 3 months proved to have actinomycosis involving the retroperitoneum and quadriceps muscle. Retroperitoneal involvement without intraperitoneal disease is rare. Computed tomography (CT), however, showed disease transgressing adjacent anatomic compartments with direct extension through the body wall and involvement of adjacent bony structures which is characteristic of actinomycosis.

MR imaging of the female pelvic region

Magnetic resonance (MR) imaging is a valuable technique for noninvasive evaluation of the female pelvic region. This article presents the normal anatomy and abnormalities of the female pelvis. MR imaging may be more useful than clinical evaluation or other imaging modalities in diagnosing or staging developmental anomalies, leiomyomas, adenomyosis, endometrial or cervical carcinoma, vaginal neoplasms, ovarian cysts, endometriosis, teratomas, polycystic ovaries, or other ovarian masses. It could potentially replace laparoscopy as a more useful tool in the diagnosis of uterine anomalies. MR imaging is generally capable of helping determine whether a pelvic mass is uterine or adnexal in origin and may be used to characterize some adnexal masses. In some cases, MR imaging is used to differentiate recurrent disease from posttreatment fibrosis, which aids in treatment planning.

Human ovarian epithelial cancer cells cultures in vitro express both interleukin 1 alpha and beta genes

Ascitic fluid from human ovarian cancer patients often contains a large number of leukocytes along with tumor cells. Some of the recent evidence suggests that the ascitic fluid contains factors capable of inducing the growth of ovarian cancer cells in vitro and in vivo. While these factors have not yet been completely characterized, growth factors secreted by the tumor cells could influence the tumor growth by paracrine and autocrine mechanisms. Earlier, we reported that ovarian epithelial cancer cells produce macrophage colony-stimulating factor. It appears that these tumor cells produce more than one cytokine. Identifying the various products secreted by the tumor cells would provide valuable information needed to understand the biology of ovarian cancer. In the present study, evidence is provided for the first time that five different human ovarian epithelial tumor cell lines and tumor cells isolated from the ascitic fluid of four cancer patients express interleukin (IL) 1 alpha and beta genes constitutively. Production of the lymphokine was determined by analyzing the cellular RNA for IL-1-related transcripts and by immunological assays. Ovarian cancer cells also secrete another pleiotropic cytokine, IL-6, constitutively. In many systems, IL-1 induces the expression of the IL-6 gene. To determine whether the basal levels of IL-6 production are dependent on the endogenous IL-1, neutralization studies were carried out. Addition of antibodies to IL-1 did not decrease the levels of IL-6 secreted by the cancer cell lines. These results suggest that multiple cytokines are produced by ovarian cancer cells and that the endogenous IL-1 may not be directly involved in the regulation of IL-6 gene expression in these cells.

Ribosomal inhibitory proteins from plants inhibit HIV-1 replication in acutely infected peripheral blood mononuclear cells

Peripheral blood mononuclear cells from seronegative donors were stimulated with phytohemagglutinin and then infected with human immunodeficiency virus (HIV-1). Using this experimental system, the antiviral activity of two translation inhibitory proteins (pokeweed antiviral protein, PAP-S, and Luffa ribosomal inhibitory protein, LRIP-I) isolated from plants and a recombinant form of ricin A chain were studied. Previously, it had been shown that toxin polypeptides linked to monoclonal antibodies could inhibit HIV-infected cells. In the present study, the free, unconjugated, proteins were found to inhibit HIV replication at doses in which they were nontoxic to uninfected peripheral blood mononuclear cells. Among the inhibitory proteins, PAP-S and recombinant ricin A chain markedly reduced the reverse transcriptase activity and the expression of p24 core protein in infected cultures. Dose response studies indicate that the anti-HIV activity of PAP-S was comparable to AZT. The other ribosome inhibitory proteins (RIPs) showed moderate but significant antiviral activity.

Coexistent adenocarcinoma and microcystic adenoma of the pancreas

A case with coexistent pancreatic adenocarcinoma and microcystic adenoma is presented. These diagnoses were suspected on the basis of their computed tomography (CT) appearances and confirmed with CT-guided fine-needle aspiration.

CT evaluation of congenital and acquired abnormalities of the azygos system

Congenital and acquired abnormalities may alter the anatomy, size, or position of the azygos system. Computed tomography is often able to depict these abnormalities and in many cases indicate the cause. In this article, the normal anatomy of the azygos system is discussed and examples of congenital and acquired abnormalities are presented.

Persistent CT nephrogram: significance in the diagnosis of contrast nephropathy--an update

Contrast nephropathy (CN), a well-known complication of intravascular contrast medium, is associated with dense cortical nephrograms. These may be detected on unenhanced computed tomography (CT). We report the initial findings of a series of patients at risk for CN who received contrast for coronary arteriography or aortic arch angiography. Unenhanced CT scans were performed 22-26 h after contrast, and the mean cortical attenuation measured. These results were correlated with serial blood urea nitrogen (BUN) and serum creatinine measurements. The patients in this study, all of whom had either elevated baseline creatinine values, were over 73 years or both, had a high incidence of cortical contrast retention and contrast nephropathy.

CT of thoracic aortic aneurysms

Aneurysms of the thoracic aorta are most often the result of arteriosclerotic disease. Other causes include degeneration of the medial layer of the aortic wall, either idiopathically or due to genetic disorders such as Marfan syndrome; aortic dissection; trauma; syphilis and other bacterial infection; noninfective aortitis; and congenital anomaly. We review normal anatomy of the aorta and discuss our technique and interpretation of computed tomography (CT) in the evaluation of the thoracic aorta. We illustrate the CT appearance of different types of aortic aneurysms as well as discuss the use of CT for assessing complications of aneurysms, for postoperative follow-up, and in the differentiation of aortic aneurysm from a paraaortic mass.

MR imaging of uterine carcinoma: correlation with clinical and pathologic findings

Thirteen patients with clinical stages I and II endometrial carcinoma were examined with magnetic resonance (MR) imaging before surgery. Depth of invasion and stage of disease were assessed, and the results were compared with those from MR images of the surgical specimens and pathologic findings. Staging with MR imaging was accurate in 11 of 13 patients (85%). Our results agree with previous reports that MR imaging is an accurate, noninvasive method of assessing depth of myometrial invasion and cervical involvement. We anticipate that MR imaging will have an increasing role in treatment of patients with endometrial carcinoma.

Persistent CT nephrogram: significance in the diagnosis of contrast nephropathy

The prospective study involved 50 patients without known renal masses or previous renal surgery who received intravascular contrast medium for various radiologic procedures and subsequently underwent unenhanced computed tomography (CT) of the kidneys 22-26 hours later. In 42 patients, cortical readings did not exceed 50 HU and corticomedullary attenuation differences (CMADs) did not exceed 10 HU. In seven patients (intermediate group), there was persistent cortical enhancement (mean attenuation, 58.3-84.8 HU; CMAD, 10.3-40.3 HU), but there was no significant rise in levels of blood urea nitrogen or serum creatinine. A single patient had contrast nephropathy and exhibited a mean cortical attenuation of 141.6 HU and a mean CMAD of 85.8 HU on the 24-hour CT scan. The authors have seen two additional cases of contrast nephropathy presaged by mean cortical attenuations of 162 and 209 HU on the 24-hour CT scan. One of these patients had been in the intermediate group in the prospective study. A cortical attenuation of 55-110 HU on a 24-hour postcontrast scan may help identify a group of patients with subclinical renal impairment who are at high risk of nephropathy on subsequent exposure to contrast medium, while cortical attenuations in excess of 140 HU seem to be an early indicator of contrast nephropathy.

Computed tomography and magnetic resonance imaging of the pericardium

Computed tomography is an established modality for the evaluation of the pericardium. It is used to evaluate complicated pericardial effusions, pericardial thickening, calcific pericarditis, pericardial cysts, postoperative changes and primary and metastatic neoplasms of the pericardium. Magnetic resonance imaging is being used with increasing frequency in the evaluation of pericardial disease. It offers advantages over computed tomography, including a potential for tissue characterization, absence of ionizing radiation or need for intravenous contrast medium, and the ability to scan in any plane. Disadvantages include greater cost, longer examination times and the inability to identify calcification positively.