Материал: Advanced Imaging of the Abdomen - Jovitas Skucas

are mostly a complication of combined irradiation and orthotopic bladder replacement.

Postoperative upper tract surveillance is with IV urography, CT, and renal US. Postcontrast MRI should reveal normal renal enhancement and visualize the neobladder. Also, MRI provides renal function data similar to that obtained with scintigraphy. Dynamic digital urography using serial image acquisition after bolus contrast injection is a novel way of studying orthotopic ileal neobladders (48), but this technique is not widely practiced.

Postoperative surgical anatomy after orthotopic bladder reconstruction can be evaluated with 3D CT (virtual endoscopy); while such imaging is useful if reoperation is required, its need on a routine basis is not established.

Postoperative Complications

Urinary tract damage occurring during various gynecologic laparoscopic procedures includes bladder perforation, ureteral injury, and bladder fistula. The prevalence of these complications after major laparoscopic gynecologic surgery is probably similar to that seen after standard surgery.

Leak

Anastomotic leakage is a recognized complication of urinary tract reconstructive surgery

ADVANCED IMAGING OF THE ABDOMEN

(Fig. 11.11). The most common site is at the urethroenteric anastomosis. A majority of leaks are extraperitoneal in location; it is the intraperitoneal pouch leaks that are more difficult to detect with imaging. A number of leaks are delayed.

Catheter drainage or stenting as appropriate is therapeutic for most leaks.

Stones/Stricture

Patients with an enterocystoplasty or continent diversion are at risk for stone formation and ureterointestinal stricture. Patients with a continent diversion are more prone to developing stones than those with an augmentation or a substitution cystoplasty.

Surgical treatment of ureterointestinal strictures consists of open ureteral reimplantation. Percutaneous antegrade dilation is a viable alternative in some patients, but is plagued by a low success rate and recurrent restenosis.

Dilated ureters are common in patients with a neobladder, and it is difficult to differentiate between partial obstruction and dilation due to reflux and other causes. An IV urogram with furosemide is occasionally helpful in such a situation. Furosemide normally results in good contrast flow distally once renal pelves are opacified; on the other hand, increased renal pelvis and caliceal dilation and the lack of contrast washout during such diuresis imply an obstruction.

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Malignancy

A low but increased risk of cancer exists after various uroenteric anastomoses, generally beginning a decade or more after surgery. These range from adenocarcinoma to transitional cell carcinoma and squamous cell carcinoma. A reasonable approach is to recommend routine annual surveillance beginning about 10 years after the initial surgery.

Other Complications

An ileoileal intussusception is an uncommon complication of bladder augmentation. Computed tomography and MR should detect this complication.

An autostapler is often used when bowel is interposed in the urinary tract, with the metallic staples buried beneath the intestinal mucosa. A staple expressed into the bladder lumen acts as a nidus for subsequent stone formation.

An occasional patient with portal hypertension develops massive bleeding from ileal conduit peristomal varices; such bleeding can be controlled with transjugular intrahepatic portosystemic shunt (TIPS).

Examination Complications

Cystography

Rupture/Extravasation

Extravasation of contrast or even frank perforation is one of the complications of cystography. Typically a tear occurs during filling of an unused or partially used bladder. Patients with chronic renal failure appear to be at increased risk. Although rare, an indwelling catheter is associated with a bladder perforation; occasionally a Foley catheter occludes the bladder outlet and results in greater pressures than normal. Nevertheless, extravasation also occurs in patients with no known underlying risk factors. The most common site is lateral to the trigone, close to the ureteral insertion.

Some patients develop intramural intravasation, while others have frank bladder wall rupture. Many of these patients remain asymptomatic. Cystoscopic findings range from isolated mucosal tears and diffuse mucosal hemorrhage to frank rupture.

Many extravasations resolve without therapy, aside from maintaining a low luminal pressure.

Autonomic Dysreflexia

In patients with previous spinal cord injury, imaging studies leading to bladder or colonic distention should be approached cautiously. Autonomic dysreflexia is caused by spinal cord lesions above the T6 level. It is not an uncommon complication in patients with a cord lesion who are undergoing manipulative urologic procedures such as cystography or voiding cystourethrography. It is also occasionally encountered with a barium enema or similar procedures. It is induced by overstimulation of a-adrenergic fibers in the bladder neck. With a rise in intravesical pressure the bladder neck is stretched and a-adrenergic receptors excrete norepinephrine. Elevated circulating norepinephrine level leads to peripheral arterial constriction and hypertension. Normally this peripheral arterial constriction is countered by splanchnic vessel dilation, but with a spinal cord lesion above T6 no reflex portal vessel dilation occurs. The resultant hypertension stimulates the carotid sinus, and aortic arch baroreceptors which result in bradycardia and vasodilation above the cord injury level. Impulses originating from stretched bladder or colon afferent sensory nerve endings ascend to the point of spinal cord injury and initiate the release of sympathetic motor impulses in efferent tracts, leading to sympathetic hyperreflexia and spasm and vasoconstriction below the level of injury. Clinically, both systolic and diastolic hypertension, bradycardia, nausea, abdominal pain and redness, and profuse sweating of the head and neck develop. It can be life-threatening.

In patients with a spinal cord lesion, constant blood pressure monitoring should be considered during manipulative radiologic procedures so that the onset of this syndrome is detected in its early phase; generally terminating the procedure and bladder drainage resolves the hypertension. Therapy of autonomic dysreflexia differs from treatment of typical contrast reactions; namely, treatment is to remove the inciting cause and treat the hypertension, if still present. Occasionally hypertension persists even when the inciting stimulus is removed, and fast-acting antihypertensive therapy may be necessary. If needed, patients at risk for auto-

nomic dysreflexia can be premedicated with a- blocking agents prior to the procedure.

Catheter Related

The balloon of a chronic indwelling catheter may not deflate. An attempt at bursting the balloon should minimize the possibility of leaving any catheter fragments in the bladder. An in vitro study comparing the results of a needle technique, overinflation, instillation of ether, and using a stylet through the inflation channel found that a needle technique achieved the best results with the fewest fragments (49).

A knot can form during catheterization of a continent stoma and lead to acute urinary retention. Similar catheter knotting within the bladder is a complication of cystourethrography; some of these knots can be untied using a stiff guidewire.

References

1.Song JH, Francis IR, Platt JF, et al. Bladder tumor detection at virtual cystoscopy. Radiology 2001;218:95–100.

2.Darge K, Bruchelt W, Roessling G, Troeger J. Interaction of normal saline solution with ultrasound contrast medium: significant implication for sonographic diagnosis of vesicoureteral reflux. Eur Radiol 2003;13:213– 218.

3.Beyersdorff D, Taupitz M, Giessing M, et al. [The staging of bladder tumors in MRT: the value of the intravesical application of an iron oxide-containing contrast medium in combination with high-resolution T2weighted imaging.] [German] Rofo Fortschr Geb Rontgenstr Neuen Bildgeb 2000;172:504–508.

4.Bernhardt TM, Schmidl H, Philipp C, Allhoff EP, RappBernhardt U. Diagnostic potential of virtual cystoscopy of the bladder: MRI vs CT. Preliminary report. Eur Radiol 2003;13:305–312.

5.Lammle M, Beer A, Settles M, Hannig C, Schwaibold H, Drews C. Reliability of MR imaging-based virtual cystoscopy in the diagnosis of cancer of the urinary bladder. AJR 2002;178:1483–1488.

6.Yanagisawa S, Fujinaga Y, Kadoya M. Urachal mucinous cystadenocarcinoma with a cystic ovarian metastasis. AJR 2003;180:1183–1184.

7.Oyar O, Yesildag A, Gulsoy UK, Perk H. The image of urachus adenocarcinoma on Doppler ultrasonography. Eur J Radiol 2002;44:48–51.

8.Peng MY, Parisky YR, Cornwell EE 3rd, Radin R, Bragin S. Computed tomography cystography versus conventional cystography in evaluation of bladder injury. AJR 1999;173:1269–1272.

9.Lemack GE, Zimmern PE. [Interstitial cystitis: reevaluation of patients who do not respond to standard treatments.] [French] Prog Urol 2001;11:239–244.

ADVANCED IMAGING OF THE ABDOMEN

10.Peters KM, Diokno AC, Steinert BW, Gonzalez JA. The efficacy of intravesical bacillus Calmette-Guerin in the

treatment of interstitial cystitis: long-term followup. J Urol 1998;159:1483–1486.

11.Anderson J, Carrion R, Ordorica R, Hoffman M, Arango H, Lockhart JL. Anterior enterocele following cystectomy for intractable interstitial cystitis. J Urol 1998;159: 1868–1870.

12.Miyazato T, Yusa T, Onaga T, et al. [Hyperbaric oxygen therapy for radiation-induced hemorrhagic cystitis.] [Japanese] Nippon Hinyokika Gakkai Zasshi 1998;89: 552–556.

13.Server Pastor G, Lopez Cubillana P, Garcia Hernandez JA, Hita Rosino E, Asensio Egea L, Rigabert Montiel M. [Eosinophilic cystitis: a single anatomopathologic entity and three different presentation forms. Proposed classification.] [Review] [Spanish] Actas Urol Esp 1996;20:155–161.

14.Parant O, Soulie M, Tollon C, Monrozies X. [Ureteral and vesicular endometriosis: case report.] [French] Prog Urol 1999;9:522–527.

15.Jequier S, Bugmann P, Brundler MA. Nephrogenic adenoma of the bladder: ultrasound demonstration. A case report. Pediatr Radiol 1999;29:185–187.

16.Oyama N, Tanase K, Akino H, Mori H, Kanamaru H, Okada K. Nephrogenic adenoma in a patient with transitional cell carcinoma of the bladder receiving intravesical bacillus Calmette-Guerin. [Review] Int J Urol 1998;5:185–187.

17.Linn JF, Sesterhenn I, Mostofi FK, Schoenberg M. The molecular characteristics of bladder cancer in young patients. J Urol 1998;159:1493–1496.

18.Herr HW, Cookson MS, Soloway SM. Upper tract tumors in patients with primary bladder cancer followed for 15 years. J Urol 1996;156:1286–1287.

19.Kim JK, Park SY, Ahn HJ, Kim CS, Cho KS. Bladder cancer: analysis of multi-detector row helical CT enhancement pattern and accuracy in tumor detection and perivesical staging. Radiology 2004;231:725–731.

20.Kim JK,Ahn JH, Park T,Ahn HJ, Kim CS, Cho KS.Virtual cystoscopy of the contrast material-filled bladder in patients with gross hematuria. AJR 2002;179:763–768.

21.Taniguchi M, Tatsuta N,Yokota H, et al. Incrustation and uptake of skeletal imaging agent in transitional cell carcinoma. J Nucl Med 1997;38:1206–1207.

22.Haleblian GE, Skinner EC, Dickinson MG, Lieskovsky G, Boyd SD, Skinner DG. Hydronephrosis as a prognostic indicator in bladder cancer patients. J Urol 1998;160: 2011–20144.

23.Bachor R, Kotzerke J, Reske SN, Hautmann R. [Lymph node staging of bladder neck carcinoma with positron emission tomography.] [German] Urologe A 1999;38: 46–50.

24.Textor HJ, Wilhelm K, Strunk H, Layer G, Dolitzsch C, Schild HH. [Locoregional chemoperfusion with mitoxantrone for palliative therapy in bleeding bladder cancer compared with embolization.] [German] Rofo Fortschr Geb Rontgenstr Neuen Bildgeb Verfahr 2000;172:462–466.

25.Lebret T, Herve JM, Yonneau L, et al. [Study of survival after cystectomy for bladder cancer. Report of 504 cases.] [French] Prog Urol 2000;10:553–560.

26.Lebret T, Gaudez F, Herve JM, Barre P, Lugagne PM, Botto H. Low-dose BCG instillations in the treatment of

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stage T1 grade 3 bladder tumours: recurrence, progression and success. Eur Urol 1998;34:67–72.

27.Ayed M, Ben Hassine L, Ben Slama R, et al. [Results of BCG in the treatment of pTa and pT1 bladder tumors. Evaluation of a long protocol using 75mg of Pasteur strain BCG.] [French] Prog Urol 1998;8:206–210.

28.Sebe P, Haab F, Nouri M, Tligui M, Gattegno B, Thibault P. [Epididymal gaseous abscess after BCG treatment.] [French] Prog Urol 2000;10:99–100.

29.Nemoto R, Nakamura I, Honjyo I, Takahashi M, Abe C. Tuberculous enteritis after intravesical bacillus Cal- mette-Guerin therapy: a case of mistaken identity. J Urol 1998;159:2091–2092.

30.Damm O, Briheim G, Hagstrom T, Jonsson B, Skau T. Ruptured mycotic aneurysm of the abdominal aorta: a serious complication of intravesical instillation bacillus Calmette-Guerin therapy. J Urol 1998;159:984.

31.Champetier D,Valignat C, Lopez JG, Ruffion A, Devonec M, Perrin P. [Intravesical BCG-therapy: comparison of side effects of Connaught (Toronto) and Pasteur (Paris) strains.] [French] Prog Urol 2000;10:542–547.

32.Lamm DL, Riggs DR. The potential application of Allium sativum (garlic) for the treatment of bladder cancer. [Review] Urol Clin North Am 2000;27:157–162.

33.Lopez-Beltran A, Pacelli A, Rothenberg HJ, et al. Carcinosarcoma and sarcomatoid carcinoma of the bladder: clinicopathological study of 41 cases. J Urol 1998;159: 1497–1503.

34.Sousa Escandon MA, Alejandro M, Garcia Figueiras R, et al.[Pulmonary thromboembolism after chronic bladder distention.] [Review] [French] Prog Urol 2001;11:323–326.

35.Monllor Gisbert J, Tano Pino F, Rodriguez Arteaga P, Galbis Palau F. [Urologic manifestations in Wolfram’s syndrome.] [Spanish] Actas Urol Esp 1996;20:474–477.

36.Moudouni S, Nouri M, Koutani A, Ibn Attya A, Hachimi M, Lakrissa A. [Obstetrical vesico-vaginal fistula. Report of 114 cases.] [French] Prog Urol 2001;11:103–108.

37.Sylla C, Fall PA, Diallo AB, et al. [Vesico-uterine fistulae. Report of 5 cases.] [French] Prog Urol 2000;10:634–637.

38.Tazi K, el Fassi J, Karmouni T, et al. [Vesico-uterine fistula. Report of 10 cases.] [French] Prog Urol 2000;10: 1173–1176.

39.Takahashi E, Nakajima F, Taoka Y, et al. [A case report of complete inversion of the bladder in an old woman.] [Japanese] Nippon Hinyokika Gakkai Zasshi 1998;89: 975–978.

40.Chen GD, Su TH, Lin LY.Applicability of perineal sonography in anatomical evaluation of bladder neck in women with and without genuine stress incontinence. J Clin Ultrasound 1997;25:189–194.

41.Kuo HC. Transrectal sonographic investigation of urethral and paraurethral structures in women with stress urinary incontinence. J Ultrasound Med 1998;17:311– 320.

42.Stoker J, Rociu E, Bosch JL. High-resolution endovaginal MR imaging in stress urinary incontinence. Eur Radiol 2003;13:2031–2037.

43.Unterweger M, Marincek B, Gottstein-Aalame N, et al. Ultrafast MR imaging of the pelvic floor. AJR 2001;176: 959–963.

44.Game X, Malavaud B, Mouzin M, Rischmann P, Sarramon JP. [Periurethral collagen injections: results after 2 years in 25 patients with severe urinary incontinence.] [French] Prog Urol 2001;11:283–287.

45.Hidar S, Attyaoui F, de Leval J. [Periurethral injection of silicone microparticles in the treatment of sphincter deficiency urinary incontinence.] [French] Prog Urol 2000;10:219–223.

46.Sundaram CP, Reinberg Y,Aliabadi HA. Failure to obtain durable results with collagen implantation in children with urinary incontinence. J Urol 1997;157:2306–2307.

47.Hautmann RE, de Petriconi R, Kleinschmidt K, Gottfried HW, Gschwend JE. Orthotopic ileal neobladder in females: impact of the urethral resection line on functional results. Int Urogynecol J Pelvic Floor Dysfunct 2000;11:224–229.

48.Sardanelli F, Zandrino F, De Cicco E, Iozzelli A, De Caro G, Pacella M. [An evaluation of orthotopic ileal neobladders by dynamic digital urography.] [Italian] Radiol Med 2000;100:37–41.

49.Gulmez I, Ekmekcioglu O, Karacagil M. A comparison of various methods to burst Foley catheter balloons and the risk of free-fragment formation. Br J Urol 1996;77:716–718.

Technique

Hysterosalpingography

Conventional

The gold standard in evaluating tubal patency is laparoscopy, although in many institutions hysterosalpingography is commonly used. In developed countries hysterosalpingography is performed with fluoroscopic visualization; in others, where fluoroscopic equipment often does not exist, a delayed anteroposterior image after contrast instillation is an alternative.

The primary application of hysterosalpingography is in evaluating infertility. This examination is readily performed by most radiologists, does not require anesthesia, and side effects and complications are uncommon, with the major complication being pelvic infection. The indications for this examination have decreased considerably, and the current major indication is to determine whether fallopian tubes are patent or not. It has been supplanted by magnetic resonance (MR) in evaluating most müllerian duct anomalies. This examination does not evaluate well the fimbriated fallopian tube ends and external structures. A lack of intraperitoneal contrast spill does not establish tubal obstruction; spasm, mucous plugs, and technical factors in performing the study also result in nonspillage. Thus in one study only 84% of the nonpatent tubes at hysterosalpingography were obstructed at perioperative salpingoscopy

(1).

A number of studies have commented on an increased pregnancy rate after hysterosalpingography. The choice of a water-soluble versus an oil-soluble contrast agent in performing hysterosalpingography does not affect the subsequent rate of term pregnancy (2).

Other Imaging Techniques

Selective catheterization of the fallopian tubes (selective salpingography) is useful if hysterosalpingography reveals a blocked tube and further intervention is contemplated. If needed, a guide wire is inserted through the tube and a catheter is advanced into the tube.At times a fallopian tube believed to be obstructed will be shown to be patent with this technique.

Endovaginal ultrasonography (US) during air and saline instillation into the uterus also evaluates tubal patency (variously called sonosalpingography, hysterosalpingosonography, and similar names). The use of B-mode US and Doppler US to assess tubal flow of a contrast agent and thus establish tubal patency have been proposed, but with limited success.

A liquid containing air bubbles, such as agitated saline or one containing human serum albumen, can be used as a contrast agent during sonographic hysterosalpingography. Fluid and air bubbles are seen in the cul-de-sac if the fallopian tubes are patent. These procedures are similar to hysterosalpingography except that endovaginal US is used.

In a woman with a contraindication to iodine-based contrast, tubal patency can be established by magnetic resonance imaging (MRI) after infusing gadolinium–diethylenetri- amine pentaacetic acid (Gd-DTPA); the presence of contrast material in the peritoneal cavity implies tubal patency.

Anecdotal hysterosalpingoscintigraphy using technetium-99m (Tc-99m)–macroaggregated albumin (MAA) has been reported.

Computed Tomography

Pelvic CT is commonly used to evaluate gynecologic disease. Computed tomography is especially useful in staging malignancies. An occasional false-positive diagnosis of malignancy does occur, and among other entities it includes pelvic actinomycosis, chronic appendicitis, and even an ectopic pregnancy.

Ultrasonography

A number of terms describe US of the female pelvic structures: sonography, sonohysterography, hysterosonography, vaginosonography, transvaginal echography, and other similar terms are used. Saline may or may not be instilled into the uterine cavity prior to scanning. The examination is performed either using a transabdominal approach or the probe is positioned in the vagina, uterus, or rectum. Ultrasonography during surgery uses a sterile intraabdominal probe.

For consistency, the terms transabdominal, endovaginal, and endorectal US are used here. Whenever intrauterine saline is instilled it is specifically mentioned. Unless Doppler is mentioned, the examination involves conventional US.

Intraoperative US is useful in guiding difficult dilation and curettage (D&C). Endovaginal sonohysterography aids some operative intrauterine biopsies and resections, although its effectiveness compared to hysteroscopy is not known.

Transabdominal US provides a general overview of the pelvis. It is limited in obese patients. Endovaginal US allows the use of higher frequency transducers and thus has better resolution than a transabdominal approach, but it has a limited field of view, especially of large tumors.

ADVANCED IMAGING OF THE ABDOMEN

The two studies are therefore complementary and at times both need to be performed.

Endovaginal US is generally considered more specific in detecting adnexal and ovarian disorders than transabdominal US. In women with postmenopausal bleeding, endovaginal US improves clinical diagnostic accuracy and the certainty of diagnosis. Both conventional and Doppler US are feasible. No definite contraindication to endovaginal US exists. A threedimensional (3D) endovaginal US technique is employed in some centers; whether it provides any advantage over the current 2D techniques remains to be established.

The terms sonohysterography and hysterosonography are generally used to indicate that the uterine cavity has been distended with fluid, usually sterile saline. It then should be qualified whether the examination is performed transabdominally or endovaginally. Sterile saline injected into the uterine cavity acts as a sonographic window for endovaginal US. Such scanning achieves higher resolution than is obtainable with conventional endovaginal US. A number of publications have reported sensitivities and specificities of over 95% for this technique in detecting intracavitary lesions, and this technique has gained wide acceptance. Yet a word of caution is in order about this procedure: A risk of intraperitoneal malignant cell dissemination exists in a setting of endometrial cancer. In an elegant study of infusion sonohysterography using 10 to 20mL of saline performed when the abdomen was open but prior to the start of a surgical procedure, fluid spilled from the fallopian tubes was shown to contain malignant cells (3). Whether the use of sterile water rather than saline to lyse free tumor cells is helpful remains to be established.

Intrauterine US has a higher sensitivity and specificity than an endovaginal approach in detecting uterine abnormalities. Some authors have suggested that intrauterine US might replace hysterosalpingography for uterine study. This may be so, although part of the reason may be the poor study quality of much of hysterosalpingography, especially with digital filming—gross contrast-filled uterine images provide no intrauterine details.

The indications for intrauterine US are not yet settled, but it appears to have a role between that of hysterosalpingography and hysteroscopy.