Features of non-small cell lung carcinomas overlooked at digital chest radiography.

PURPOSE: To examine the imaging features of non-small cell lung carcinomas (NSCLC) overlooked at digital chest radiography (dCXR), and compare general and thoracic radiologists' performance for lung carcinoma detection at dCXR. METHODS: Frontal and lateral dCXR from 30 consecutive patients with lung carcinoma overlooked during initial interpretation and 30 normal controls were independently retrospectively reviewed by two blinded thoracic radiologists and, in a separate review, three blinded general radiologists. The location, size, histopathology, borders, presence of superimposed structures, and lesion opacity were recorded. Interobserver agreement was calculated, and the detection performance between thoracic and general radiologists was compared. RESULTS: The average patient age was 67.9 years (range 47-82 years). The average size of carcinomas missed by the thoracic radiologists was 18.1mm (range 10-32 mm). Lesion margins were circumscribed in 29% (2/7), and 71% (5/7) of missed lesions were obscured by anatomical superimposition. Seventy-one percent (5/7) of missed lesions were solid nodules on computed tomography (CT) images. Forty-three percent of lesions were located in the upper lobes and 63% were adenocarcinomas. Compared with general radiologists, the seven NSCLC missed by the thoracic radiologists tended to be smaller (p=0.063), had significantly lower CT density measurements (-92.4+/-87.5 HU versus -70+/-87.2 HU, p=0.050), and more commonly had an ill-defined margin (p=0.026). The clinical stage of the overlooked lesions did not differ between the two groups (p=0.480). CONCLUSIONS: The lesion size, location, conspicuity, and histopathology impact the likelihood of lung carcinoma detection at dCXR in a fashion similar to that of conventional film-screen techniques.

Bilateral traumatic carotid-cavernous fistulae: Strategies for endovascular treatment.

BACKGROUND: Most traumatic carotid-cavernous fistula/e (TCCF) are unilateral, and simultaneous bilateral TCCF are uncommon. The purpose of this study was to evaluate the angiographic architecture of bilateral TCCF and report our experience with their endovascular management. METHOD: Over 15 years, 252 consecutive patients with TCCF were referred to our institute for endovascular treatment. Bilateral TCCF occurred in 5 men and 2 women with a mean age of 31 years. The angiographic architectures of bilateral TCCF were evaluated with cerebral angiography. All patients underwent a single session of transarterial embolisation by using various permanent embolic materials and were followed up clinically or with angiography for a mean of 22 months (range 9-36 months). FINDINGS: All patients presented with neuro-ophthalmic symptoms and signs. No new instances of cerebrovascular ischemia or intracranial haematoma resulted from bilateral TCCF. All fistulae were associated with partial arterial steal and were successfully occluded by using a detachable balloon and/or a detachable coil with or without a liquid adhesive. Of 14 TCCF, 9 were completely obliterated with preserved flow of the internal carotid artery (ICA). In the other 5 fistulae, the ICA had to be sacrificed to achieve occlusion because the anatomy of the fistula was complex. All fistula related symptoms resolved immediately or gradually during clinical follow up. No clinically significant procedure related neurological complications or recurrent fistulae were observed. CONCLUSIONS: All bilateral TCCF were associated with a partial arterial steal phenomenon. Single session endovascular treatment using various embolic materials was effective in managing these high-flow fistulae. In all patients, it was possible to preserve one or both ICAs.

Peritoneal serous papillary carcinoma: a reappraisal of CT imaging features and literature review.

We evaluated the imaging features of primary serous peritoneal carcinoma (PSPC) on computed tomography (CT) and reviewed the literature. Preoperative CT images of 11 women with PSPC were retrospectively reviewed. The clinical presentations and serum levels of CA-125 were recorded. Special attention was paid to the operative and histopathologic findings of the ovaries. Imaging features were correlated with those in the literature. An elevation of serum CA-125 was found in 91% of cases. The CT findings included ascites (82%), peritoneal nodules or masses (73%), and omental nodules or omental caking (64%). Absence of an overt ovarian mass was observed in 64% of cases. The clinical manifestations and imaging features in our patients were consistent with those in the literature. Eighty-five percent of the ovaries in our study were superficially involved by PSPC in histopathologic examination. In none of our cases could the ovarian size be clearly assessed in the CT images. In conclusion, the presence of diffuse peritoneal disease and the absence of an ovarian mass on CT and an elevation of serum CA-125 level is suggestive of PSPC. However, in our experience, the evaluation of ovarian morphology and size by CT alone may not be as reliable.

Correlation of three-dimensional tumor volumetry with cervical cancer prognostic parameters.

OBJECTIVE: Estimation of tumor size by a single diameter is used in the current Federal International Gynecology Oncology (FIGO) cervical cancer staging system. However, the role of three-dimensional volumetry is rarely mentioned. In this study, three kinds of tumor volume estimations were performed and the relationship of these volume estimations among associated cervical cancer prognostic parameters were evaluated. METHODS: Thirty patients with newly diagnosed cervical cancer at Taipei Veterans General Hospital were enrolled in the study. Final pathology and associated parametric information was obtained by chart review. The original magnetic resonance (MR) image was reappraised by an experienced radiologist and the tumor volume was estimated using either three axial measurements or the longest axial measurement. The corresponding three-dimensional (3-D) volume was calculated by the integration of lesion areas in different images using volumetric software developed by engineers at National Central University, Taiwan. All data were analyzed separately for correlation with clinical staging, histological differentiation, pelvic lymph node metastasis and survival status. RESULTS: A statistically significant difference in tumor volume estimates was found between 3-D-integration and one-dimensional estimates among tumors with lymph nodes metastasis, cell differentiation and parametrial involvement. CONCLUSION: This study found that the parameters of lymph node metastasis, parametrial involvement and tumor differentiation are volume-dependent. 3D-tumor volumetry showed superior discrimination of these parameters compared to current single diameter evaluation suggesting its potential as a rapid method for initial prediction of prognostic factors in cervical cancer.

A comparative MR and pathological study on fetal CNS disorders.

OBJECT: We used MR after sonography to help us in prenatal counseling in 58 complicated pregnancies from 1998 to 2000. METHODS: All fetal MR examinations were undertaken with a 1.5-T magnet using a body-phased-array coil and an ultrafast imaging technique, half-Fourier single-shot turbo spin-echo (HASTE). Twelve fetuses were found to have major anomalies, and in each of these cases either delivery was induced or the pregnancy was terminated. In 6 of the fetuses, with anomalies of the central nervous system, postmortem examinations were then performed after they failed to survive, and these constitute the patient sample investigated in the current study. The fetal gestational ages in these 6 cases ranged from 24 to 32 weeks. MR imaging demonstrated morphological details of the anomalies. They were: alobar holoprosencephaly in 2, middle interhemispheric fusion in 1, alobar holoprosencephaly with Dandy-Walker malformations in 1, a Dandy-Walker variant in 1 and twin-twin transfusion syndrome with hypoxic-ischemic injury to the brain in 1. CONCLUSIONS: Postmortem examinations confirmed the MR diagnoses, and these observations support us in improving our understanding of the pathogenesis of fetal CNS anomalies.

Lithopedion.

Lithopedion is a rare obstetrical outcome of an undiagnosed and untreated advanced abdominal pregnancy, mostly found incidentally. We present a case of lithopedion. In a 76 year-old female suffering from cervical neoplasm, total abdominal hysterectomy was performed for the lesion and the lithopedion was found incidentally. The patient's history was unremarkable, and laboratory tests were normal. The patient recalled having experienced a severe abdominal pain about 50 years before. Her physician had felt "a benign tumor" in her pelvis at that time, indicating that the stone child had retained in the maternal peritoneal cavity for 50 years.

Preoperative staging of cervical carcinoma with MR imaging: a reappraisal of diagnostic accuracy and pitfalls.

The purpose of this study was to assess the diagnostic accuracy and pitfalls of MR imaging in preoperative staging of cervical cancer. Magnetic resonance imaging was performed to determine the tumor staging for 41 patients with cervical carcinoma emphasizing tumor size, parametrial invasion, vaginal invasion, and lymph node metastases. According to the correlation of MR findings with surgical-pathological features, there was less than 5 mm discrepancy in the size in 29 of 34 tumors (85.3%) that were larger than 1 cm. In assessing parametrial invasion, vaginal invasion and lymph node metastases, MR imaging had an accuracy of 95, 83, and 86%, respectively. In determining stage of disease and differentiating operable (< or =stage IIA) from advanced disease (> or =stage IIB), MR imaging had an accuracy of 82.9 and 93%. Pitfalls leading to staging errors included difficulties in differentiating cancer foci from surrounding tissue edema and detecting microscopic tumor extension. Magnetic resonance imaging is accurate in the evaluation of parametrial invasion and differentiation of operable from advanced disease. The ability of MR imaging to detect microscopic extra-cervical tumor extension and differentiate cancer foci from surrounding tissue edema is not as reliable.

Spontaneous expulsion of a uterine submucosal leiomyoma after administration of a gonadotropin-releasing hormone agonist.

A 40-year-old primigravida presented with acute urine retention. Ultrasound examination revealed a large uterine submucosal leiomyoma and GnRH-a was administered. The leiomyoma grew to over twice its original size and protruded through the introitus. After 10 days, it was expelled completely and removed by resectohysteroscopy. The expulsion of the leiomyoma was most likely a result of GnRH-a's flare-up effect.

Cervical carcinoma: assessment of parametrial invasion and lymph node metastasis with magnetic resonance imaging.

BACKGROUND: Clinical tumor staging of cervical carcinoma has its limitations. The purpose of this study was to stage cervical carcinoma by magnetic resonance imaging (MRI), with an emphasis on the assessment of parametrial invasion and pelvic lymph node metastasis. METHODS: MRI was performed in 51 women with tissue-proven cervical carcinoma 2 weeks prior to surgery. Images were analyzed for parametrial invasion, pelvic lymph node metastasis and tumor stage. The results were compared with the histopathologic findings after surgery in all patients. RESULTS: In assessing parametrial invasion, MRI had an accuracy of 94%. In assessing pelvic lymph node metastases, MRI was accurate in 86.3% of cases. In determining stage of disease, MRI had an accuracy of 76.5%. The accuracy of MRI in differentiating localized (< or = stage IIA) from advanced disease (> or = stage IIB) was 94.1%. CONCLUSIONS: MRI is accurate in the evaluation of parametrial invasion and lymph node metastases and in the differentiation of localized and advanced disease. MRI is beneficial in planning treatment for patients with cervical cancer.

Transurethral resection of the prostate-related changes in the prostate gland: correlation of MRI and histopathology.

PURPOSE: The purpose of this work was to demonstrate signal changes of the prostatic urethra after transurethral resection of the prostate (TURP) on MR images and histopathologic correlation. METHOD: Sixty-three patients with prostate cancer confirmed by either TURP (Group A, 19 patients) or transrectal biopsy (Group B, 44 patients) were evaluated by endorectal MRI before radical prostatectomies. The MR images of postcurettaged prostatic urethras were correlated with the histopathologic features. RESULTS: On the T2-weighted images, a thin zone of hypointense signal surrounding the curettaged prostatic urethra was identified in 52.6% (10/19) of Group A patients, imaged soon after (mean 21.1 days) TURP, but was indiscernible in Group B patients and the other Group A patients, imaged later after TURP (mean 49.2 days). This hypointense signal zone histopathologically correlates with a zone of inflammatory tissue reaction surrounding the widened urethra. CONCLUSION: Inflammatory tissue reaction surrounding curettaged prostatic urethra after TURP accounts for the presence of a low signal zone on T2-weighted images.

High resolution MRI of adrenal glands in patients with primary aldosteronism.

BACKGROUND: We studied the role of high-resolution magnetic resonance imaging (MRI) of the adrenal glands using a surface coil in patients with primary aldosteronism to differentiate aldosterone-producing adenomas (APA) from idiopathic hyperplasia of the adrenal gland (IHA). The data obtained were used to decide on surgical or nonsurgical treatment for patients. METHODS: High-resolution MRI with SE T1WI, FSE T2WI and paired in- and out-phase images of the adrenal glands of 41 patients with clinically documented primary aldosteronism were collected. The images were reviewed in comparison with other differentiating tests. RESULTS: Nineteen of the 41 patients were diagnosed with APA on MRI. Surgical and pathologic proof of APA was obtained in 10 cases and solitary macronodular hyperplasia was found in one case. Among these 11 cases, there were no false positive findings on MRI, while correct detectability of high-resolution computerized tomography (CT) was 62.5% (5/8); for adrenal venous sampling, it was 37.5% (3/8); and for NP-59 adrenal scanning, it was 42.9% (3/7). In eight cases with biochemically favored APA and no surgical proof, MRI and CT showed the same lesion detection rate, while there was no concordance with venous sampling, and concordance of only 33.3% (2/6) for adrenal scanning. In the remaining 22 patients without focal lesions on MRI, there was poor concordance among the four test modalities, with frequently conflicting results. CONCLUSIONS: In patients with definitive results of noninvasive biochemical tests for APA, and positive findings of unilateral, focal adrenal lesion on MRI or CT, unilateral adrenalectomy may be justified without further tedious and invasive examinations. CT should still be the first screening test; however, high-resolution MRI is a useful diagnostic supplement for patients with strong clinical evidence of APA and negative or equivocal findings on CT.

Struma ovarii mimicking a benign multicystic ovarian tumor: MR imaging in one case.

Struma ovarii is a rare form of mature teratoma of the ovary. A case of struma ovarii is presented with magnetic resonance (MR) imaging and pathologic findings. MR imaging showed a multiloculated cystic adnexal mass with well-defined margin and septum. Internal cystic spaces presented homogeneous signal intensity of fluid content in both T1-weighted and T2-weighted images. Subtle contrast enhancement was depicted in internal septi. Imaging features were indistinguishable from benign multicystic ovarian tumor, and different from the reported cases in the literature.

MR findings of renin-secreting tumor: a case report.

The renin-secreting tumor is a rare benign tumor of the kidney. It is usually detected in young hypertensive patients with high plasma renin activity and hypokalemia. We describe the magnetic resonance findings of a case of renin-secreting tumor of the kidney.

Prostate cancer: local staging with endorectal magnetic resonance imaging.

BACKGROUND: Prostate cancer has received increasing attention during the past decades. Staging of tumors before treatment is imperative for planning appropriate therapy. The purpose of this study is to assess the role of endorectal magnetic resonance imaging (MRI) in local staging of prostate cancer. METHODS: Endorectal MRI was performed in 31 patients with histologically-proven prostate cancer. MRI was done three to 100 days (mean, 32.1 days) after either transrectal ultrasonography (TRUS) with biopsy or transurethral resection of the prostate (TURP). Radical prostatectomies were performed within two weeks after MRI. The diagnostic accuracy of endorectal MRI for local tumor staging, specifically for extracapsular extension (ECE) and seminal vesicle invasion (SVI), was evaluated by correlating MRI results with histopathologic findings of whole-mount specimens. RESULTS: The accuracy of endorectal MRI for the detection of tumor presence and estimation of tumor volume was 48%. Sensitivity, specificity and positive predictive value for evaluation of ECE were 88%, 69% and 80%, respectively, and for SVI, were 66%, 84% and 50%, respectively. The overall accuracy of MRI in local tumor staging (using the TMN system) was 61%. Accuracy in differentiating localized from invasive cancer was 84%. CONCLUSION: Endorectal MRI is not accurate enough to detect tumor presence or estimate tumor volume. Diagnostic accuracy for local tumor staging is unsatisfactory. However, endorectal MRI is highly accurate in differentiating localized (stage B) from invasive (stage C) cancer.

Tuberculosis of the prostate: MR appearance.

Tuberculosis of the prostate is uncommon. Here we present a case of tuberculosis of the prostate with its MR findings.

The "Fisherman's Waders" sign in a bone scan of inferior vena cava thrombosis associated with nephrotic syndrome.

This paper presents a 61-year-old male patient with nephrotic syndrome, hypercoagulability and IVC thrombosis. Increased soft tissue uptake below the level of the mid chest was seen in his bone scan. The term "Fisherman's Waders" sign is suggested for this finding, whose recognition may permit the identification of inferior vena cava obstruction in bone scans. The existence of a cavo-portal shunt was also confirmed by dynamic scintigraphy.