PubMed HealthSearch

Biomedical subjects

H M Pollack

Publications and source records attributed to H M Pollack.

At least 19 recordsLinked to original sources

Magnetic resonance imaging in carcinoma of the prostate.

Over the past few years, magnetic resonance imaging (MRI) has been shown to be of great value in imaging the pelvis. Its advantages derive from its multiplanar capability and high soft-tissue contrast, which are particularly significant in imaging the prostate and seminal vesicles. MRI, particularly with endorectal surface coils, provides excellent visualization of the prostate and periprostatic anatomy in multiple planes. It is also useful in evaluating the remainder of the pelvis, including lymph nodes and the bony pelvis. This makes MRI the most reliable noninvasive staging modality for prostate cancer.

Humans

MR imaging in adenocarcinoma of the prostate: interobserver variation and efficacy for determining stage C disease.

Patients with adenocarcinoma of the prostate confined to the gland (stage B) are candidates for a potentially curative surgical procedure (radical retropubic prostatectomy). However, patients with adenocarcinoma that penetrates the capsule or invades the seminal vesicles (stage C) are no longer considered good candidates for surgical cure of their disease. The purpose of this study was to compare the ability of four radiologists to detect stage C disease on MR images and to evaluate interobserver variability. One hundred consecutive MR studies of the prostate were reviewed independently by four radiologists to determine whether the cancer was stage C (capsule penetration or seminal vesicle invasion by tumor). A radical prostatectomy was performed in each case, and careful histologic assessment was made of the prostatic capsule and seminal vesicles for any evidence of stage C disease. The sensitivity, specificity, and accuracy (true-positive + true-negative/100 patients) in detecting stage C disease were calculated for each of the four readers. Four receiver-operating-characteristic curves were generated and compared by means of the univariate z score. Percentage agreement was calculated for five specific areas of the prostate on MR images, and observations made by the best reader were compared with the other three to help determine interreader variability. The results showed that the sensitivity and specificity of MR imaging in detecting stage C disease ranged from .24 to .61 (mean, .48) and .49 to .79 (mean, .66), respectively. The accuracy of MR imaging ranged from .47 to .61 (mean, .55). The univariate z score test showed that one of the readers significantly differed from the other three. The average percentage agreement between that reader and the other three was 70% for the five separate anatomic regions. This study shows that considerable interobserver variation exists in the interpretation of MR images for staging cancer of the prostate. The average accuracy among four radiologists in determining the presence of stage C adenocarcinoma of the prostate from MR images was only slightly above a chance guess at .55.

Adenocarcinoma

The seminal tract in patients with ejaculatory dysfunction: MR imaging with an endorectal surface coil.

Twenty-six patients with signs and symptoms of ejaculatory dysfunction (hemospermia, hypospermia, oligospermia, or painful ejaculation) were examined with high-resolution MR imaging with an endorectal surface coil. Findings were abnormal in 15 patients. Abnormalities detected included four cases of müllerian cysts, three cases of wolffian cysts, one case of anaplastic prostatic carcinoma, and various noncystic abnormalities of the seminal vesicles and ejaculatory ducts, including ejaculatory duct obstruction and seminal vesiculitis. In all cases, depiction of both the normal and abnormal anatomy of the entire seminal tract, including the vas deferens, seminal vesicles, and ejaculatory ducts, was excellent. This depiction of the detailed anatomy of the prostatic cysts made it possible to suggest specific diagnoses. Our results show the value of MR imaging with an endorectal surface coil in the examination of patients with ejaculatory dysfunction.

Adolescent

Computed tomography and magnetic resonance imaging of the female lower urinary tract.

Computed tomography (CT) and magnetic resonance (MR) imaging have become invaluable imaging modalities in the diagnosis of diseases involving the lower urinary tract. Both CT and MR imaging are able to accurately stage bladder carcinoma, with MR imaging able to distinguish between superficial and deep muscle invasion of tumor. CT and MR are also the studies of choice for evaluating retroperitoneal fibrosis, which often affects the urinary tract; MR imaging is often able to detect the presence of active inflammation and occasionally rule out a malignant cause. MR imaging holds promise for the evaluation of stress urinary incontinence and urethral disease. Although diseases of the distal ureter continue to be most accurately diagnosed by intravenous urography and retrograde studies, CT and MR imaging may serve a helpful secondary role.

Female

Prostate cancer: local staging with endorectal surface coil MR imaging.

Endorectal surface coil magnetic resonance (MR) imaging was used to stage the local extent of prostate cancer in 22 patients. The endorectal coil images were acquired with a 10-12-cm field of view and a 4-mm section thickness. All pathologic specimens were reviewed by one pathologist. Endorectal surface coil MR imaging was 82% accurate in the differentiation of stage B from stage C cancer. One case was overestimated, and three cases were underestimated. The three underestimated cases consisted of two cases of microscopic capsular invasion and one case of minimal seminal vesicle invasion. In a comparison of retrospective, blinded readings of endorectal coil and body coil images, there was an average improvement in accuracy of 16% in staging prostate cancer with endorectal coil images.

Carcinoma

Imaging of the prostate gland.

The advent of ultrasonography and the development of intrarectal techniques have made possible semiquantitative prostatic volumetrics for more accurate preoperative assessment of benign prostatic hyperplasia (BPH) as well as earlier diagnosis of prostatic carcinoma (PC). Computed tomography has increased the scope of prostatic imaging by including regional lymph nodes as well. Magnetic resonance imaging (MRI) has enabled viewing of the internal architecture of the prostate gland, thus allowing precise diagnosis of BPH and recognition of carcinoma. MRI is also the most exact method of staging PC.

Diagnostic Imaging

Imaging of patients with stage D prostatic carcinoma.

In conclusion, it would appear from present evidence that several statements can be made. First, MRI is the most accurate method of staging the periprostatic spread of carcinoma. Both the prostate and the regional nodes can be evaluated. The role of ultrasound is, at present, unclear. Second, the utility of CT has diminished with the emergence of high-quality MRI, but in situations in which MRI scans are inconclusive (e.g., in the assessment of paraaortic node disease, in which images are degraded by peristaltic movement), CT may be useful. Third, the choice of method for the assessment of nodal disease is a more difficult question. Although MRI and CT have replaced lymphography in most centers, the latter study, especially when combined with fine-needle aspiration biopsy, still is useful. Fourth, bone metastases are best assessed with scintigraphy, which can point to areas requiring supplemental plain radiography. An MRI study of the spine, although highly sensitive, is not practical. Fifth, MRI is superior to CT myelography in assessing spinal disease. Finally, the chest radiograph is the mainstay of assessing chest involvement.

Abdominal Neoplasms

Staging of renal carcinoma using magnetic resonance imaging at 1.5 Tesla.

The preoperative magnetic resonance imaging (MRI) studies of 31 patients with surgically proven renal cell carcinomas obtained with a 1.5 Tesla unit were retrospectively reviewed to assess the accuracy of MRI for staging of tumor. According to the Robson classification 12 patients were found at surgery to have Stage I renal carcinoma, three patients had Stage II, ten had Stage IIIA, one had Stage IIIB, two had Stage IIIC, one had Stage IVA, and two had Stage IVB disease. Twenty-five (81%) of 31 patients were staged correctly by MRI. Clearly MRI showed venous tumor extension without the need for intravenous contrast administration. Also, MRI had a negative predictive value of 95%, and a positive predictive value of 100% for the evaluation of inferior vena cava tumor thrombus. At 1.5 Tesla MRI is an excellent staging modality in the preoperative evaluation of renal carcinoma. It is especially recommended in patients with equivocal computed tomography findings and in all patients with contraindications to the intravenous use of iodinated contrast material.

Adolescent

Magnetic resonance imaging of the prostate gland.

MRI, because of its multiplaner capability and high soft tissue contrast, is ideally suited for examination of the prostate. The normal prostatic zonal architecture and periprostatic anatomy can be visualized. The use of an endorectal surface coil greatly enhances resolution. Clinical application to the study of BPH, prostate carcinoma, prostatic cysts, and inflammatory disease is discussed. MRI appears to be emerging as the modality of choice for imaging the prostate.

Adenocarcinoma

Masson's tumor of the kidney: a new renal lesion.

Intravascular papillary endothelial hyperplasia (Masson's tumor) is a rare benign reactive lesion usually found in thrombosed subcutaneous blood vessels. We report a case of Masson's tumor of the kidney, and discuss the relevant clinical, radiographical and pathological aspects.

Endothelium, Vascular

Radiographic imaging and urologic decision making in the management of renal and ureteral calculi.

Without question, significant changes, and for the most part significant advances, have been made in the management of patients with urolithiasis during the past decade. The newer therapeutic measures have generally made it easier for patients to be treated, but the decision-making process for the urologist has become more complex. In the past, the issue whether to follow a patient with a stone or to intervene with surgery or transurethral cystoscopic basketing was decided based on well-established guidelines that had developed over many years. Today, the indications for intervention appear to be less stringent, and in the minimally symptomatic or asymptomatic patient who would not have been operated on previously, there appears to be an expanding desire for prophylactic management. For whatever reasons, once it has been established that a stone is present and the decision has been made to intervene, subsequent decisions regarding the technical approach may also not be as simple as in the past. Ten years ago, for example, a stone in the abdominal ureter was removed by a ureterolithotomy, and the principal decision involved placement of the incision. Today, the same calculus may be approached by ESWL with or without a stent, by antegrade percutaneous techniques, or by retrograde ureteroscopic techniques using rigid or flexible endoscopes with baskets, ultrasonic lithotrites, or lasers. Although the specific indication for specific techniques continue to evolve, it has become evident that information obtained by the radiographic evaluation of the urinary tract is critical in the decision-making process. The intravenous urogram, including the initial plain film, remains the primary diagnostic modality and, in the absence of extenuating clinical features, is often the sole test required to make a decision regarding the best therapeutic modality. A variety of clinical features from the history or physical examination, or concerns raised by the intravenous urogram, may necessitate alternative or additional techniques to better define the anatomy, the renal function, or other pathology. The urologist therefore needs to be familiar with the information that can be obtained from the uroradiologist's vast armamentarium in order to make the most appropriate recommendations to the patient for diagnosis and management.

Diagnostic Imaging