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The Scar Solution Natural Scar Removal

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0/+

M+ = bone marrow infiltration

TO = no malignancy, e.g. scar, fibrosis, granulation tissue, hypertrophy T+ = malignancy

+ + = highly accurate + = accurate 0 = not accurate - = not possible

Note:

M+ = bone marrow infiltration

TO = no malignancy, e.g. scar, fibrosis, granulation tissue, hypertrophy T+ = malignancy

+ + = highly accurate + = accurate 0 = not accurate - = not possible between acute oedema, early granulation tissue, and the various stages of superficial tumours (stages Ta and T1). When MR imaging is available, CT-scanning is no longer needed.

Future developments

Technological improvements are being introduced rapidly. With the new generation MR-scanners, faster sequences with a higher resolution can be applied. With the new MR-units it is possible to perform a high-resolution Tl-weighted 3D MP-RAGE sequence with isometric voxels (1.4 x 1.4 x 1.4mm) in five minutes. Also, ultra-fast, multislice dynamic imaging becomes possible. At present, seven slices can be made with a time resolution of two seconds, allowing evaluation of urinary bladder cancer and its metastases with high specificity at multislice. The high signal-to-noise ratio, obtained with new phased array-coils, facilitates the use of a fast T2-weighted sequence with a 1024 x 1024 matrix. For evaluation of the extent of muscle invasion, the combination of an external with an endorectal-phased array-coil and these sequences seems promising.

Fast dynamic imaging

The behaviour of urinary bladder cancer after IV injection of a Gd-containing contrast agent as documented with fast dynamic MR imaging and time-images are a reflection of its neovascularity. Microvessel quantification is reported to be an independent predictor of survival in patients with invasive bladder cancer and might be useful in selecting those who would benefit from adjuvant therapy.8 Fast dynamic MR imaging is more accurate compared to conventional unenhanced MR imaging in the follow-up of chemotherapy.9

MR guided biopsy

MR imaging has advantages over other imaging modalities for biopsy guidance. As MR imaging is a three-dimensional imaging technique, it facilitates multiple-angulated biopsy and can best be performed under MR-guidance. A good example in bladder cancer is the three-dimensional visualization of (enlarged) lymph nodes and the subsequent MR-guided biopsy (Figure 7). In a preliminary study we performed MR-guided biopsies in 13 patients with slightly enlarged nodes, and in 10 of them biopsy was true positive.9

Another advantage of (contrast-enhanced) MR imaging is the higher specificity and sensitivity in showing urinary bladder cancer and possible metastases compared to ultrasonography or CT-scanning. Based on the enhancement pattern of the tumour, with MR-imaging, the part of the tumour that contains the most pathologic vessels, and thus the most viable part of the tumour, can be localized and biopsied. At present specially designed MR-units are being developed in order to simplify localization under MR-guidance and to reduce biopsy time. With regular MR-machines, biopsies must be performed in the way it is done with CT-scanning. Special non-magnetic needles are available, but efforts must be made to further reduce susceptibility artifacts of these needles.

In the near future fast, high resolution, dynamic contrast-enhanced MR imaging of the urinary bladder will further improve the diagnosis, staging and follow-up of patients with urinary bladder cancer. Therefore, this technique will be used more and more frequently in these patients. MR-guided biopsy will contribute to a less invasive diagnosis, resulting in better treatment planning.

Preferred radiological approach

At present, MR imaging is the first mode of choice in imaging the urinary bladder and its cancer. However, due to limited resources in the healthcare system, this technique should only be used to obtain information that directly influences therapeutic management and outcome. To achieve this, the expertise of both urologists of MR imaging and radiologists of clinical handling is needed. Therefore, continuous education and communication between these two specialities is vital.

Detection of bladder cancer should be performed by cystoscopy and histology. Once bladder cancer is diagnosed, the following step should be staging. For superficial tumours, clinical staging, which includes transurethral resection, is the best technique. In addition, an IVU can be performed to rule out multifocal carcinoma in pyelum or ureter. Superficial tumours, without muscle invasion (stages <2) are treated with local endoscopic resection with or without adjuvant intravesical installations. Follow-up will be performed by means of repeated cystoscopy every three to six months. No further radiological imaging is needed in these patients.

If, however, there is muscle invasion, further staging should be performed with MR imaging. Attempts will be made to cure patients with muscle invasion (stages T2a and T2b), perivesical infiltration (stages T3a and T3b) or invasion into prostate, vagina or uterus (stage T4a) by radical cystectomy and lymphadenectomy. In cases ofpelvic sidewall or abdominal wall infiltration (stage T4b), or metastases in pelvic lymph nodes or bone marrow, palliative chemo- or radiation therapy will be given. Follow-up of these therapies can be best monitored with fast dynamic MR imaging.

Acknowledgement

This paper was reprinted with permission from Springer Verlag.10

References

1 Barentsz JO (1997) MR imaging of urinary bladder carcinoma. In: Jafri SZH (ed) Genitourinary Radiology Diagnostic & Therapeutic. Springer: New York, pp. 138-58.

2 Barentsz JO, Ruijs JHJ and Strijk SP (1993) Review article. The role of MR imaging in carcinoma of the urinary bladder. AJR 160: 937-47.

3 Barentsz JO, Debruyne FMJ and Ruijs JHJ (1990) Magnetic resonance imaging of carcinoma of the urinary bladder. In: Barentsz JO (ed) Magnetic Resonance Imaging of Carcinoma of the Urinary Bladder. Kluwer Academic Publishers: Dordrecht, London, Boston.

4 Barentsz JO, Boetes C, Verstraete KL, Jager GJ, Mus RDM and Ruijs SHJ (1995) Dynamic Gadolinium-enhanced MR imaging of the body. Clinical MRI 88-93.

5 Barentsz JO, Jager GJ, van Vierzen PBJ et al. (1997) Staging urinary bladder cancer after transurethral biopsy: the value of fast dynamic contrast-enhanced MR imaging. Radiology 203: 645-52.

6 Barentsz JO, Jager GJ, Witjes JA and Ruijs JHJ (1996) Primary staging of urinary bladder carcinoma: the role of MR imaging and a comparison with CT. European Radiology 6: 1349.

7 Barentsz JO, Witjes JA and Ruijs JHJ (1997) What's new in bladder imaging? Urologic Clinics of North America 24: 583-602.

8 Barentsz JO (1997) MR-intervention in the pelvis: an overview and first experiences in MR-guided biopsy in nodal metastases in urinary bladder cancer. Abdominal Radiology 22: 524-30.

9 Barentsz JO, Berger-Hartog O, Witjes JA et al. (1998) Fast dynamic contrast-enhanced MR imagin in the evaluation of chemotherapy in advanced bladder cancer. Radiology 207: 791-7.

10 Barentsz JO, Engelbrecht MRW, Witjes JAM, de la Rostete JJMCH, van der Graaf M (1999) MRI of the male pelvis. Eur Radiol 9: 1722-36.

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