CHAPTER A - nomesco

Supplementary chapter Z
STRUCTURE AN D CLASSIFICATION GUIDELINES
The supplementary codes of chapter Z are general qualifiers, applicable in principle to all main and subordinate chapters.
The basic procedure codes are not changed in definition or code designation by the addition of one or more supplementary
codes.
The character Z in position 1 of the code denotes the chapter as in all other chapters. Characters X, Z and S in position 2 of
the code denote unspecified region. The codes are available to characterise procedures of all other chapters. In case a group
of codes is specific to a main or subsidiary chapter, the second character identifies the corresponding chapter.
As of this updated edition, the following groups exist:
• ZC codes specify the use of certain techniques in surgery of the eye.
• ZF codes specify the use of certain techniques in surgery of the heart and major thoracic vessels (chapter F).
• ZL codes specify the use of certain techniques in gynaecological surgery (chapter L).
• ZP codes specify the use of certain techniques in surgery of peripheral vessels and lymphatic system.
• ZQ codes specify the use of certain techniques in surgery of the skin. Includes : Subcutaneous tissue.
• ZS codes link the present procedure to previous surgery, with the addition of a position 3 character indicating the main
or subordinate chapter of previous surgery.
• ZU codes specify the use of certain techniques in transluminal endoscopy.
• ZX codes characterise various circumstances and events in surgery.
• ZZ codes characterise reconstructive use of tissue: Free tissue transplants (excluding bone and tissue of the eye and orbit);
flaps and free microvascular grafts, including composite flaps and microvascular grafts with bone. The codes specify the
nature and origin of such transplants or flaps. Finally, there are ZZ codes for the use of tissue expanders in addition to or
as an alternative to tissue transplantation.
For future editions, chapter Z groups specific to other main or subsidiary chapters may be developed. However, chapter Z
groups specific to chapter X are not envisaged.
Specific elements of the code structure
In all chapters except chapter Z, the use of certain characters in certain positions of the code carries particular significance in
the following manner:
• X in position 2 denotes unspecified region within the body system in question.
• W in position 2 denotes reoperations, without specification of region within the body system in question.
• W in position 3 denotes possible procedure groups not presently found in the classification (“Other procedure” groups).
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