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OBJECTIVE: For optimum treatmentplanning and to establish the prognosis, the main objectivesof diagnostic imaging techniques after detecting a tumorin the urinary bladder are to determine 1) its nature andhistological structure, 2) depth of bladder wall invasion,3) tumor localization and involvement of the ureter andtrigone, 4) involvement of bladder wall lymphatics, and(5) to determine if there is or no regional and/or distantmestastasis. The capabilities of the diagnostic imagingtechniques in regard to achieving the foregoing objectivesare analyzed.METHODS: This study comprised 160 patients with asuspected or confirmed bladder tumor. The imagingmethods utilized were: conventional radiology includingIVP, retrograde and double contrast cystography,ultrasound, CT and MRI.RESULTS: Analysis of the images allowed assessmentof 18 morphological parameters, of which the followingwere among the most relevant: presence of ureterohydronephrosis,filling defect(s), tumor localization, tumorbase, tumor-mucosa angle, wall stiffness, total wallthickness, changes observed in the perivesical space anddegree of pelvic lymph node involvement.Visualization of a bladder filling defect confirms abladder tumor. The predictors of the biological behaviourof bladder tumors, such as wall stiffness and lumenasymmetry, characteristically express tumor invasiveness.The tumor-mucosa angles in relation to tumor base andperitumoral edema express a higher grade of infiltrationfor the obtuse angles and a lower grade for the acuteangles.Determining tumor stage with accuracy is the essentialchallenge of the imaging methods in the assessment ofbladder cancer. Both CT and MRI are used to analyze fourbasic aspects prior to treatment: 1) tumor appearance,2) presence or absence of perivesical invasion, 3) presenceor absence of invasion of the adjacent organs, and4) presence or absence of lymphadenopathies.The accuracy of CT for tumor staging is estimated to be88%-92% for stage D1 and 80%-85% for stages C and B2,respectively, while MRI has an accuracy of 95% for stageB2 and 85% for tumor stages that compromise adjacentorgans such as the prostate, uterus or vagina.CONCLUSIONS: Conventional radiological methods,together with transabdominal or transrectal ultrasound,have a high rate of accuracy for tumor detection.Determination of the stage of tumor invasion requiresanalysis of wall thickness, width of tumor base, tumormucosaangles and perivesical space. CT and MRI providehighly reliable diagnostic information on the foregoing.CT may present some difficulty in determining the stage ofbladder wall invasion. With contrast enhancement, MRIhas shown a greater capability to differentiate tumorstages B2 and C and is very similar to CT in detectingpelvic or retroperitoneal lymph node involvement.
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OBJECTIVE: To review the usage ofmagnetic resonance imaging (MRI) in the assessment ofthe male pelvis.METHODS: The applications of MRI in male pelvispathology are reviewed.RESULTS/CONCLUSION: MRI has been demonstratedto be a useful diagnostic imaging technique in male pelvispathology. It has been used mainly to evaluate the prostate,particularly for preoperative staging. MRI can depicttumor invasion of the capsule, periprostatic plexus, seminalvesicles, bladder, rectum and pelvic lymph nodes. Its mainobjective is to differentiate stages T1 and T2 of advanceddisease. The endorectal coil enhances image resolutionand diagnosis of extracapsular disease is more precise.MRI can also distinguish scar tissue from regionalrecurrence in patients submitted to radical prostatectomy.This imaging technique has also been used to assessbenign lesions of the prostate and seminal vesicles; e.g.,prostatic cysts, focal nodular hyperplasia, and amyloidosisof the bladder. Although ultrasound continues to be theprimary noninvasive diagnostic method in the evaluationof scrotal pathology, MRI provides valuable diagnosticinformation in certain conditions; e.g., testicular tumors,inflammatory processes, testicular torsion and trauma.
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OBJECTIVE: To analyze the utility ofmagnetic resonance imaging (MRI) in the assessment ofthe female pelvis, with special reference to the technicalaspects.METHODS: Our experience and the literature on MRIin the evaluation of the female pelvis are reviewed.RESULTS / CONCLUSIONS: Conventional MRIassessment, which includes T1- and T2-weighted imagesin the axial, sagittal and coronal planes and T2 acquisitionsalong the major axis of the uterus in the sagittal plane, hasproved effective in evaluating different pathologies of thefemale pelvis. MRI is particularly effective in stagingendometrial carcinoma and in determining myometrial orcervical invasion. It is also useful in determiningparametrial invasion in cervical carcinoma. In ovariandisease, MRI has been used in detecting peritonealinvolvement, adenopathies and to characterize the lesion.It is particularly useful for planning the surgical approachin congenital disease.The high resolution of MRI with the use of the new coilshas enhanced its efficiency and effectiveness in the diag-nosis of congenital anomalies and tumors of the femaleurethra, and in the evaluation of prolapse of the urinarybladder and urinary incontinence
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.- OBJECTIVE: We report on the comparative3-dimensional (3D) living female pelvic floor geometry infive women, comparing the volume, morphology, andintegrity of the levator sling, and pelvic anatomicrelationships among study subjects.METHODS: Five women of varying ages, parity,continence, and prolapse status were studied. Two-dimensional (2D) imaging of the pelvic floor organs wasperformed on each subject in the supine position. Manualsegmentation techniques and solid modeling software wasused to build 3D models of each patient's pelvic floorstructures, which could then be viewed and measured onthe computer screen. We measured levator muscle volume,posterior urethro-vesical angle, distance from the urethrato pubo-coccygeal line, and the levator plate angle. Theintegrity of pubo-coccygeal attachments was also recorded.RESULTS: Levator muscle volume ranged from 68ml inthe nulliparous female, to 26ml in the grand multipara with severe prolapse and mild genuine stress incontinence(GSI). The second lowest volume (30ml) was in themultipara with GSI. Volumes in the parous subjects withoutstress urinary incontinence or pelvic organ prolapse were36 and 39ml. Pubo-coccygeal attachments were found tobe torn in the 2 symptomatic subjects, and were intact inall 3 asymptomatic subjects.CONCLUSION: MR based 3D modeling is feasible andcan be used in a research setting to evaluate complexanatomic relationships which may accompany pelvic floordysfunction. The technique can also be used to evaluatelevator muscle morphology and volume, as well as pelvicfloor support integrity and its possible role in GSI andprolapse. We are currently conducting a larger study tovalidate our technique, and to better define the relationshipbetween pelvic floor geometry and pelvic floor dysfunction
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- OBJECTIVES: This study was carried out1) to analyze the growth and clinical manifestations ofrenal adenocarcinoma; 2) to determine the presence oftumor, its malignant nature, size, local extent or distantspread and route of dissemination according to the imagingmethods utilized, and 3) to determine the accuracy of thedifferent imaging procedures, such as IVP, US, CT, andMRI, in staging renal adenocarcinoma.These objectives attempted to provide answers to thefollowing questions: a) Are there currently substantialchanges in the biological behavior of renaladenocarcinoma?, b) Does the route of tumor dissemination(direct infiltration through the capsule, lymphohematogenous, cancer embolus carried by the blood streamto a distant location) affect the rate of progression tostages III and IV?, and c) What are the most relevantfindings of the imaging methods that aid in determiningthe extent of the renal tumor?METHODS: 106 renal masses were evaluated; of these,93 were renal adenocarcinomas. The diagnosis, clinicalevaluation and preoperative staging were based on theclinical history, physical examination, symptoms andimaging methods (IVP, US, CT, and MRI) to assess renalmorphological changes, presence of calcifications, masseffect, tumor mass ultrasound characteristics, densitometryor MR signal pattern, perinephric fat involvement, venousvasculature, involvement of renal fascia, locoregionallymph nodes or metastasis and distant neoplastic changes.RESULTS: A third of the tumors had a size greater than 10 cms and practically half were 5-10 cms in size.Calcifications were found in 47%; 85% were punctiformand showed a central location. 88% of the tumors showedareas of necrosis. Due to the presence, in most of the cases,of a viable tumor, necrosis, calcification or cysticdegeneration, the adenocarcinomas showed a veryinhomogeneous ultrasound pattern and with varyingdegrees of vascularization on CT volumetric assessment.Invasion of perinephric fat and tumor fibrous septaewere found in 65% on CT evaluation, although MRI wasparticularly sensitive in detecting fat infiltration in theearly stages of perinephric involvement, venous thrombosis, involvement of adjacent and distant organs andtumor hemorrhagic changes.CONCLUSIONS: In determining the biologicalbehaviour of renal adenocarcinoma, preoperative stagingof infiltration and prognosis, US, volumetric CT and MRIare currently the diagnostic methods with the highestaccuracy, specificity and sensitivity. These diagnosticmethods allow early detection of tumors thereby makingthem potentially curable. Lymphatic drainage of the tumor may be determinant in its more or less rapid progression from Robson stage II to IIIa and IIIb, andthereafter to stage IV. CT and MRI showed a higheraccuracy for tumor detection, localization, determininglocal extent, tumor characterization and staging. Detection of a tumor pseudocapsule comprised of reactivefibrous tissue and compact renal parenchyma by CT orMRI allows determination of the borders of the renaltumor. Lymph node involvement radically changes theprognosis and survival in renal adenocarcinoma.
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OBJECTIVES: To establish the role ofMRI in renal disease, its indications, advantages anddisadvantages. To briefly describe the main MRI techniquesand renal features depicted on MRI before and afteradministration of a contrast agent, and present the MRIfindings in different renal conditions.METHODS: The images were obtained with the GE MR0, 5 T. T1- and T2-weighted spin echo and echo gradientsequences were utilized according to the protocoldescribed in the article.RESULTS/CONCLUSIONS: MRI is very useful in thestudy of renal disease due to its high spatial resolution. Itscost, and because it is not widely available, have limitedthe indications of MRI to those cases whose diagnosiscannot be established by other imaging techniques (USand CT) and patients in whom iodated contrast material(i.e., allergy to iodine or renal failure) or ionizing radiation(i.e., pregnancy) is contraindicated. MR has a highdiagnostic reliability in the evaluation of the extent of therenal tumors. MR angiography and MR urography permitadequate and non-invasive assessment of the vascular andcollecting systems without the need to utilize iodatedcontrast agents.
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OBJECTIVE: To review the utility of MRimaging in the assessment of renal masses, with specialreference to the morphological characteristics of thedifferent tumor types. Staging of renal cell carcinoma isalso discussed.METHODS: The literature on the use of MRI in theevaluation of renal masses is reviewed. The technicalaspects and the indications of MR urography are discussedand compared with those of other imaging techniques.RESULTS/CONCLUSIONS: MRI permits multiplanaranalysis and facilitates detection and characterization oflesions. Furthermore, it allows clear depiction of therelationships of the tumor and the adjacent structures forefficient surgical planning
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OBJECTIVE: The detection of renal masses< 3 cm has continually increased over the last few yearsdue to the improvements and wide use of imaging techniquesthat have made early diagnosis of renal carcinoma possibleand therefore to directly influence patient survival. Theapproach to small renal lesions based on our experienceand the data published in the literature are analyzed.METHODS/RESULTS: The small renal lesion isproblematic and indeterminate because of its size, whichmakes it difficult to measure its density before and aftercontrast administration on CT assessment, and is the maindiagnostic factor in this disease.Small renal masses constitute a diagnostic challengewhose resolution may lead to disproportionate surgery.This has led us to utilize multiphasic helical CT withspecific protocols and to look for data in the naturalhistory of the renal tumor to complement the radiologicalfindings. Series have been published that demonstrate that theslow growth and degree of malignancy of small renaltumors warrant a regular helical CT control evaluationbecause it allows comparison of the findings and detectsgrowths < 1 cm, which is a sign of malignancy andconsequently an indication for surgery.CONCLUSION: Due to the natural course of smallrenal tumors and the reproducibility of multiphasic CT,the correct approach is to perform close follow-up ofpatients at surgical risk or with an equivocal diagnosisusing this imaging technique.
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OBJECTIVE: To present the findings and discuss the diagnostic possibilities of helical CT angiography and digital substraction angiography, and to compare their capabilities to depict renal vascular anatomy (arterial and venous) and the pathological changes. METHODS: The findings obtained by the different imaging modalities of CT angiography were compared with those of digital substraction angiography in more than 2000 studies performed at our hospital. RESULTS: Agreement and correlation between CT angiography and digital substraction angiography, the gold standard, were found in the vast majority of the cases. In conjunction, various image post-processing possibilities of CT angiography achieved almost 100% sensitivity and specificity. CONCLUSION: CT angiography is capable of obtaining results that overlap with those of optimum quality digital substraction angiography and is a less invasive and less costly procedure. The time required is shorter and the radiation dose exposure is markedly lower for patient and staff. Helical CT is a minimal invasive technique with an increasing role in the evaluation of the renal vessels. Although its field of applications has not yet been completely established, it is less invasive, less costly, radiation exposure of patient and staff performing the procedure is lower, and has had a considerable impact in the diagnosis and management of vascular disorders. CT angiography is applicable to a number of indications of conventional angiography and has permitted vascular screening studies where one would be reluctant to indicate catheter arteriography. This imaging procedure is mainly used for 1) screening of patients that may have renovascular hypertension that may be amenable to surgical or intraluminal treatment; 2) follow-up of treated patients; 3) preoperative assessment of kidney donors; 4) evaluation of renal artery aneurysms (uncommon), aneurysms extending to the renal arteries or dissection of the aorta. It is also effective, but only slightly superior to conventional CT, in depicting thrombosis or tumor invasion of renal veins, although it is highly effective in evaluating anatomical variations and renal vein anomalies. In inflammatory vascular disease it is similar to catheter angiography, although its impact is not considerable due to the low prevalence of inflammatory vascular disease in our setting
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OBJECTIVE: To evaluate the penile echoDoppler study and review the anatomy, perfusion,innervation and physiology of erection.METHODS: The technique, spectral morphologicalchanges of the cavernous arteries after drug-inducederection, modifications and normal values are described.RESULTS/CONCLUSION: Impotence or erectiledysfunction, which is defined as the inability of the maleto achieve or sustain an erection sufficient for successfulsexual intercourse, is a benign condition with an importantimpact on the wellbeing of the patient. Statistical studieshave shown a high age-dependent prevalence in healthysubjects and an association with different conditions inpatients.To establish whether impotence is organic or not and toidentify its underlying cause require submitting the patientto not a few diagnostic tests. Since most of the cases oforganic impotence are of vascular origin, it is necessaryto utilize a diagnostic method that can identify patientswith an underlying vascular disorder (the most commoncause) and distinguish those with arteriogenic impotencefrom those with insufficiency of the complex corporealveno-occlusive system.
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OBJECTIVE: To determine the efficacy of balloon dilatation in the treatment of ureteral strictures and analyze the outcome according to its etiology. METHODS: 77 ureteral dilatations were performed in 74 patients. Most of the strictures were postoperative sequelae and the other cases were due to chronic inflammatory conditions. RESULTS: The overall success rate was 47%, partial improvement was achieved in 17% and the failure rate was 36%. In our series, the postoperative strictures res- ponded slightly better to balloon dilatation than those arising from chronic inflammatory conditions. CONCLUSION: Endourologic techniques based on the percutaneous methods of interventional radiology have reduced the usage of invasive conventional surgery in the treatment of strictures. Although the proportion of unsatisfactory results is not negligible, balloon dilatation should be the first treatment option for ureteral strictures because it is less invasive, carries a low morbidity and requires a shorter hospitalization. If the results are unsatisfactory, re-dilatation can be attempted or conventional open surgery can be performed.
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OBJECTIVE: To review the radioisotopestudies in Nephrourology that are frequently performed inthe Nuclear Medicine Department, their clinicalapplications and diagnostic yield.METHODS/RESULTS: Radionuclide studies inNephrourology allow evaluation of different aspects ofrenal function after intravenous injection of radioisotopesby blood volume/time (ml/min) measurements (glomerularfiltration rate, effective renal plasma flow) or visualizationin the form of images or graphic display (renal scintigraphy,sequential study, renography) that permit determination of the differential renal function. A sequential study,diuresis renography or angiotensin converting enzyme(ACE) inhibitor renography can be performed to evaluatethe changes in renal function induced by the diuretics orACE inhibitors. Radionuclide cystography permitsdetecting vesicoureteric reflux. These radioisotope studiesare commonly utilized in detecting reflux nephropathyand renal scarring (renal scintigraphy and radionuclidecystography), obstructive nephropathy (diuresisrenography), renovascular hypertension (ACE inhibitorrenography) and in evaluating renal transplantation(sequential study, renography, diuresis renography andACE inhibitor renography).CONCLUSION: Radionuclide studies have differentapplications in Nephrourology, some of which areconsidered to be diagnostic gold standards, such as renalscintigraphy with DMSA to detect cortical anomalies,ACE inhibitor renography to identify hypertensive patientsthat will not benefit from revascularization surgery and todetermine the glomerular filtration rate. Other studies,such as diuretic renography, are not considered to be goldstandards due to the lack of standardized protocols.
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OBJECTIVE: To review and discuss the applications of positron emission tomography (PET), with special reference to genitourinary tumors. METHODS: Our experience and the relevant literature on PET are reviewed. The principles and technical aspects of PET, the different parameters analyzed, its clinical indications, applications in genitourinary tumors and research are discussed. RESULTS/CONCLUSION: Positron emission tomography (PET) permits visualization and determination in vivo of a number of tissue and organ physiologic and biomolecular parameters.PET is also used for biomedical research and is especially useful for research and development of new drugs, tumor biomolecular phenotyping and for monitoring gene therapy. It has also proved to be a useful non- invasive diagnostic imaging technique in the clinical setting with an excellent cost-effectiveness in cancer patients. Fluor-deoxyglucose-F18 or FDG is the only radiotracer with a clinical application. PET detects the intense tumor uptake of FDG due to the higher glycolytic index of tumor cells. The PET tomograms allow performing a complete study of the whole body in the same session. The clinical indications of FDG PET that are currently accepted and established are: diagnosis of benign versus malignant solitary lung nodule, pre-treatment study to determine the extent of non-small cell lung cancer, localization and re-staging of colorectal cancer recurrence, extent and post-treatment assessment of lymphomas and extent of recurrent malignant melanoma.The application of FDG PET in genitourinary cancer is controversial. It does not appear to be useful in the initial diagnosis of primary prostatic, bladder and kidney tumors. Its clinical yield appears to be better for localizing recurrence and re-staging patients with increased prostatic specific antigen (PSA) levels after treatment of a primary prostatic tumor. Furthermore, it can also be used to determine the extent of hypernephroma and malignant bladder tumor suspected to be metastatic at the initial diagnosis. In testicular germ cell tumors, FDG PET can be a very useful tool for pre-treatment staging and to evaluate post-treatment residual masses.
