CT Colonography vs. Colonoscopy - Association For Medical Ethics

Predictive Value
for Success

EXCELLENT
> 25% of all studies are Level I

GOOD
> 25% of all studies are Level II or better

FAIR
> 25% of all studies are Level III or better

POOR
> 25% of all studies are Level IV or better

VERY POOR
< 25% of all studies are Level IV or better

Evidence Based
Medicine
Level Rating System

LEVEL I
Randomized, controlled clinical trials - This is the most objective and valid study results. This study has posted the highest level of quality for evidence based medicine.

LEVEL II
Prospective non-randomized, comparative studies - This is the second most objective and valid study results.

LEVEL III
Retrospective comparative or case controlled studies - These studies look back historically and compare them with other cases in the past. The problem with this system is that these past patients may not have been chosen or treated - or not treated at all - on equal standings.

LEVEL IV
Case Series - This where a group of patients have a particular treatment, and then observations are made about them. This does not differentiate between the success or failure of the treatment compared to other treatments or no treatment at all. For example treating back pain for 10 days by drinking pomegranate juice may show all patients got better and conclude this should be the treatment for back pain. However, usually all back pain gets better in 10 days no matter what one does.

LEVEL V
Expert opinion. This is a person's opinion only. It's an editorial, and is considered the lowest level of evidence to support a position. AME considers this to be Comparable to hearsay.

For More Information
On Evidence Based Medicine
Rating System Click Here

AME Star Rating System

CT COLONOGRAPHY vs. COLONOSCOPY

AME STAR RATING:
POOR Predictive Value for success of procedure in using CT Colonography compared to Colonoscopy

QUESTION: Is CT Colonography better or worse than colonoscopy for diagnostic screening?

No regard is given to treatment - which is not possible with CT colonography - nor cost analysis.

METHOD: Pubmed was searched for “CT Colonography” (CTC) in English language peer reviewed literature and limited to diagnostic analyses where it was compared to colonoscopy. Repetitive evaluation and similar results of same data sets were not included. Out of 56 articles and citations, 18 were found to be relevant to the question at hand, and were evaluated.

Total: 18 CT COLONOGRAPHY STUDIES
Studies FAVORABLE Towards CT Colonography Click Here to see studies	Nine Studies	2 Level III 2 Level IV 5 Level V
Studies UNFAVORABLE Towards CT Colonography Click Here to see study	Five Studies	2 Level I 3 Level II
Studies NEUTAL Towards CT Colonography Click Here to see studies	Four Studies	2 Level II 1 Level IV 1 Level V
Preponderance of studies favorable are Favorable and > 25% are Level IV or better

Click Here for description of Evidence Based Medicine Click Here for description of AME Rating System

REFERENCES

CT COLONOGRAPHY vs. COLONOSCOPY
Studies Favorable: 9

Level III: 2 Studies
1. Eur Radiol. 2007 Dec;17(12):3112-22. Epub 2007 Jun 5. Links
Feasibility study of computed tomography colonography using limited bowel preparation at normal and low-dose levels study.
Florie J, van Gelder RE, Schutter MP, van Randen A, Venema HW, de Jager S, van der Hulst VP, Prent A,
Bipat S, Bossuyt PM, Baak LC, Stoker J.
Department of Radiology, Academic Medical Center, G1-230, P.O. Box 22660, 1100 DD, Amsterdam, The Netherlands. J.Florie@amc.uva.nl
Prospective patients undergoing CTC without bowel prep and for eval of lesion only > 10 mm compared to colonoscopy in same
For CTC - only for lesions > 10mm
Level III - Favorable
Level due to limitation of endpoint – as in case control study - to only lesions > 10 mm

2. Gut. 2002 Aug;51(2):207-11. Links
Performance of multidetector computed tomography colonography compared with conventional colonoscopy.
Gluecker T, Dorta G, Keller W, Jornod P, Meuli R, Schnyder P
For CTC – for lesions > 10 mm
Level III - Favorable
Non-consecutive study patients

Level IV: 2 Studies
1. Australas Radiol. 2007 Oct;51 Spec No.:B144-6. Links
Usefulness of virtual colonoscopy in the diagnosis of symptomatic large colonic lipomas.
Koktener A, Erden A.
Case report – 2 patients
For CTC –
Level IV - Favorable
Case series, uncontrolled

2. Acta Radiol. 2005 Nov;46(7):664-70. Links
A retrospective evaluation of patient acceptance of computed tomography colonography ("virtual colonoscopy") in comparison with conventional colonoscopy in an average risk screening population.
Juchems MS, Ehmann J, Brambs HJ, Aschoff AJ.
Department for Diagnostic Radiology, University Hospitals of Ulm, Ulm, Germany.
markus.juchems@medizin.uni-ulm.de
For CTC
Level IV - Favorable
Case control, poor reference standard.

Level V: 5 Studies

1. Eur Radiol. 2005 Nov;15 Suppl 4:D138-41. Links
Virtual colonoscopy: clinical application.
Laghi A.
University of Rome La Sapienza, Polo Didattico Pontino - Latina, Via Franco Faggiana 34, 04100 Latina, Italy.
andrea.laghi@uniroma1.it
For CTC
Level V - Favorable
2. Cancer Imaging. 2005 Nov 23;5 Spec No A:S133-9. Links
Virtual colonoscopy for colorectal cancer screening: current status.
Heiken JP, Peterson CM, Menias CO.
For CTC
Level V - Favorable
Expert opinion
3. Gastroenterology. 2005 Jul;129(1):328-37. Links
Mass screening with CT colonography: should the radiation exposure be of concern?
Brenner DJ, Georgsson MA
For CTC
Level V - Favorable
4. Eur J Cancer. 2002 Nov;38(16):2070-8. Links
CT colonography (virtual colonoscopy) for the detection of colorectal polyps and neoplasms. current status and future developments.
Gluecker TM, Fletcher JG
For CTC
Level V - Favorable
5. Australas Radiol. 2002 Mar;46(1):1-12. Links
Computed tomography colonography (virtual colonoscopy): review.
Mendelson RM, Forbes GM.
Level V - Favorable

CT COLONOGRAPHY vs. COLONOSCOPY
Studies Unfavorable: Total 5

Level I: 2 Studies
1. World J Gastroenterol. 2008 Jan 21;14(3):469-73. Links
Single-center study comparing computed tomography colonography with conventional colonoscopy.
Roberts-Thomson IC, Tucker GR, Hewett PJ, Cheung P, Sebben RA, Khoo EE, Marker JD, Clapton WK.
Testing of previously developed diagnostic criteria of colonoscopy in series of 227 consecutive patients against CTC in same patients with blinding of colonscopists
Against CTC – Sensitivity for detecting smaller polyps currently not adequate compared to colonoscopy
Level I - Unfavorable
Testing of previously developed diagnostic criteria in series of consecutive patients (with universally applied reference "gold" standard)
2. Am J Med. 2008 Jan;121(1):e7; author reply e9. Links
Meta-analysis of air contrast barium enema, computed tomography colonography, and colonoscopy.
Smith LA, Sidhu P, Sidhu S, Rembacken B.
http://www.ncbi.nlm.nih.gov/pubmed/17349438?ordinalpos=1&itool=EntrezSystem2.PEntrez.Pub
med.Pubmed_Results Panel.Pubmed_DiscoveryPanel.Pubmed_Discovery_RA&linkpos=
2&log$=relatedarticles&logdbfrom=pubmed
Meta analysis of 30 studies comparing the three entities for effectiveness of CTC
Against CTC - Sensitivity for detecting smaller polyps currently not adequate compared to colonoscopy
Level I - Unfavorable
Systematic review of Level I studies.

Level II: 3 Studies
1. Acta Radiol. 2006 Nov;47(9):888-98. Links
Diagnostic performance of computed tomography colonography in symptomatic patients and in patients with increased risk for colorectal disease.
Reuterskiöld MH, Lasson A, Svensson E, Kilander A, Stotzer PO, Hellström M.
Department of Radiology, The Sahlgrenska Academy at Göteborg University, Göteborg, Sweden. maria.r@telia.com
Prospective study of patients undergoing CTC and colonoscopy
Against CTC – low sensitivity for lesions < 10mm
Level II - Unfavorable
2. Acta Radiol. 2007 Oct;48(8):831-7. Links
Diagnostic performance of computed tomography colonography and colonoscopy: a prospective and validated analysis of 231 paired examinations.
Arnesen RB, von Benzon E, Adamsen S, Svendsen LB, Raaschou HO, Hansen OH.
Department of Surgery and Department of Radiology, Hillerød Hospital, Hillerød, Denmark.
Prospective blinded study in 241 patients undergoing CTC and colonoscopy
Against CTC – lesions under 10 mm missed by significantly greater amount
Level II - Unfavorable
3. Gastroenterol Hepatol. 2007 Aug-Sep;30(7):375-80. Links
Computed tomography colonography compared with conventional colonoscopy for the detection of colorectal polyps.
Chaparro Sánchez M, del Campo Val L, Maté Jiménez J, Cantero Perona J, Barbosa A, Olivares D, Khorrami S, Moreno-Otero R, Gisbert JP.
Department of Gastroenterology and Hepatology, University Hospital La Princesa, Madrid, Spain. mariachs2005@gmail.com
Prospective study 54 patients undergoing CTC and colonoscopy
Against CTC – low sensitivity for lesions under 10 mm
Level II - Unfavorable

CT COLONOGRAPHY vs. COLONOSCOPY
Studies Neutral: Total 4

Level II: 2 Studies
1. Eur J Gastroenterol Hepatol. 2003 Dec;15(12):1323-31. Links
Computed tomography colonography in routine clinical practice.
Gallo TM, Galatola G, Fracchia M, Defazio G, De Bei F, Pera A, Regge D
Neutral - CTC can be used when colonoscopy not possible
Level II - Neutral
Diagnostic criteria based on consecutive patients

2. Clin Radiol. 2007 Jul;62(7):645-50. Epub 2007 Apr 6. Links
CT colonography versus colonoscopy in the follow-up of patients after diverticulitis -
a prospective, comparative study.
Hjern F, Jonas E, Holmström B, Josephson T, Mellgren A, Johansson C.
Division of Surgery, Department of Clinical Sciences, Danderyd Hospital, Karolinska Institut, Stockholm, Sweden. fredrik.hjern@ds.se
Prospective study 50 patients undergoing CTC and colonoscopy
Neutral - CTC “reasonable” for diverticulitis f/u
Level II - Neutral

Level IV: 1 Study
1. Med J Aust. 2006 Jun 5;184(11):546-50. Links
A comparison of colorectal neoplasia screening tests: a multicentre community-based study of the impact of consumer choice.
The Multicentre Australian Colorectal-neoplasia Screening (MACS) Group.
1679 patients offered one of six screening methods for colon cancer to evaluate change in participation rate by choice of testing. None found.
Level IV - Neutral
Prospective cohort

Level V: 1 Study
1. Scand J Gastroenterol Suppl. 2006 May;(243):139-45. Links
Computed tomography colonography: current issues.
Nio Y, Van Gelder RE, Stoker J.
Department of Radiology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands. c.y.nio@amc.uva.nl
Neutral CTC
Level V - Neutral