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Official Description

Secondary repair of dura for cerebrospinal fluid leak, anterior, middle or posterior cranial fossa following surgery of the skull base; by free tissue graft (eg, pericranium, fascia, tensor fascia lata, adipose tissue, homologous or synthetic grafts)

© Copyright 2026 American Medical Association. All rights reserved.

Common Language Description

The procedure described by CPT® Code 61618 involves a secondary repair of the dura mater, which is the outermost layer of the protective covering of the brain and spinal cord. This repair is specifically indicated for cases where there is a leakage of cerebrospinal fluid (CSF) from the anterior, middle, or posterior cranial fossa. Such leaks may occur following surgical interventions on the skull base, including tumor resections or repairs of vascular lesions, when the initial closure of the dura has proven inadequate. The secondary repair utilizes a free tissue graft, which can be sourced from various tissues such as pericranium, fascia, or tensor fascia lata, or may involve adipose tissue, homologous grafts, or synthetic materials. The graft is meticulously shaped and positioned over the area of the dural deficit, and it is secured in place to create a watertight seal, thereby preventing further CSF leakage. This procedure is critical in ensuring the integrity of the central nervous system and preventing complications associated with CSF leaks, such as infection or neurological deficits.

© Copyright 2026 Coding Ahead. All rights reserved.

1. Indications

The secondary repair of the dura for cerebrospinal fluid leak is indicated in the following situations:

  • CSF Leak Leakage of cerebrospinal fluid from the anterior, middle, or posterior cranial fossa following skull base surgery.
  • Failure of Primary Closure Instances where the primary closure of the dura has failed, necessitating a secondary intervention.
  • Post-Surgical Complications Complications arising from surgical procedures involving the resection of tumors or repair of vascular lesions in the skull base.

2. Procedure

The procedure for the secondary repair of the dura involves several critical steps to ensure effective closure and prevention of CSF leakage:

  • Harvesting the Graft A free tissue graft is harvested from the surgical approach, which may include tissues such as pericranium, fascia, or tensor fascia lata. Alternatively, adipose tissue, homologous grafts, or synthetic grafts may be utilized, depending on the specific requirements of the repair.
  • Trimming the Graft The harvested graft is then trimmed to the appropriate size and shape to adequately cover the dural deficit. This step is crucial for ensuring a proper fit and effective sealing of the area.
  • Placement of the Graft The graft is positioned over the dural defect, starting from the inferior midline and extending bilaterally around the area of concern. This methodical placement is essential for achieving a watertight closure.
  • Suturing the Graft The graft is sutured into place, ensuring that it is securely attached to the dura. This step may involve checking for any potential leakage by irrigating the graft with saline before finalizing the closure.
  • Final Closure After confirming the integrity of the graft, the final closing sutures are placed, and any necessary reinforcement is applied to ensure a complete watertight seal. In cases where a local or regionalized vascularized pedicle flap or myocutaneous flap is used, the flap is evaluated for viability, rotated, trimmed to fit the defect, and secured in layers to maintain the watertight closure.

3. Post-Procedure

Post-procedure care following the secondary repair of the dura involves monitoring for any signs of CSF leakage and ensuring the integrity of the graft. Patients may require imaging studies to assess the success of the repair and to rule out any complications. Additionally, appropriate pain management and follow-up appointments are essential to evaluate the healing process and address any concerns that may arise during recovery.

Short Descr REPAIR DURA
Medium Descr SECONDARY RPR DURA CSF LEAK FREE TISSUE GRAFT
Long Descr Secondary repair of dura for cerebrospinal fluid leak, anterior, middle or posterior cranial fossa following surgery of the skull base; by free tissue graft (eg, pericranium, fascia, tensor fascia lata, adipose tissue, homologous or synthetic grafts)
Status Code Active Code
Global Days 090 - Major Surgery
PC/TC Indicator (26, TC) 0 - Physician Service Code
Multiple Procedures (51) 2 - Standard payment adjustment rules for multiple procedures apply.
Bilateral Surgery (50) 0 - 150% payment adjustment for bilateral procedures does NOT apply.
Physician Supervisions 09 - Concept does not apply.
Assistant Surgeon (80, 82) 2 - Payment restriction for assistants at surgery does not apply to this procedure...
Co-Surgeons (62) 1 - Co-surgeons could be paid, though supporting documentation is required...
Team Surgery (66) 2 - Team surgeons permitted; pay by report.
Diagnostic Imaging Family 99 - Concept Does Not Apply
APC Status Indicator Inpatient Procedures, not paid under OPPS
Type of Service (TOS) 2 - Surgery
Berenson-Eggers TOS (BETOS) P1G - Major procedure - Other
MUE 2
CCS Clinical Classification 9 - Other OR therapeutic nervous system procedures

This is a primary code that can be used with these additional add-on codes.

69990 Addon Code MPFS Status: Restricted APC N ASC N1 PUB 100 CPT Assistant Article 1Microsurgical techniques, requiring use of operating microscope (List separately in addition to code for primary procedure)
51 Multiple procedures: when multiple procedures, other than e/m services, physical medicine and rehabilitation services or provision of supplies (eg, vaccines), are performed at the same session by the same individual, the primary procedure or service may be reported as listed. the additional procedure(s) or service(s) may be identified by appending modifier 51 to the additional procedure or service code(s). note: this modifier should not be appended to designated "add-on" codes (see appendix d).
59 Distinct procedural service: under certain circumstances, it may be necessary to indicate that a procedure or service was distinct or independent from other non-e/m services performed on the same day. modifier 59 is used to identify procedures/services, other than e/m services, that are not normally reported together, but are appropriate under the circumstances. documentation must support a different session, different procedure or surgery, different site or organ system, separate incision/excision, separate lesion, or separate injury (or area of injury in extensive injuries) not ordinarily encountered or performed on the same day by the same individual. however, when another already established modifier is appropriate it should be used rather than modifier 59. only if no more descriptive modifier is available, and the use of modifier 59 best explains the circumstances, should modifier 59 be used. note: modifier 59 should not be appended to an e/m service. to report a separate and distinct e/m service with a non-e/m service performed on the same date, see modifier 25.
22 Increased procedural services: when the work required to provide a service is substantially greater than typically required, it may be identified by adding modifier 22 to the usual procedure code. documentation must support the substantial additional work and the reason for the additional work (ie, increased intensity, time, technical difficulty of procedure, severity of patient's condition, physical and mental effort required). note: this modifier should not be appended to an e/m service.
55 Postoperative management only: when 1 physician or other qualified health care professional performed the postoperative management and another performed the surgical procedure, the postoperative component may be identified by adding modifier 55 to the usual procedure number.
58 Staged or related procedure or service by the same physician or other qualified health care professional during the postoperative period: it may be necessary to indicate that the performance of a procedure or service during the postoperative period was: (a) planned or anticipated (staged); (b) more extensive than the original procedure; or (c) for therapy following a surgical procedure. this circumstance may be reported by adding modifier 58 to the staged or related procedure. note: for treatment of a problem that requires a return to the operating/procedure room (eg, unanticipated clinical condition), see modifier 78.
62 Two surgeons: when 2 surgeons work together as primary surgeons performing distinct part(s) of a procedure, each surgeon should report his/her distinct operative work by adding modifier 62 to the procedure code and any associated add-on code(s) for that procedure as long as both surgeons continue to work together as primary surgeons. each surgeon should report the co-surgery once using the same procedure code. if additional procedure(s) (including add-on procedure(s) are performed during the same surgical session, separate code(s) may also be reported with modifier 62 added. note: if a co-surgeon acts as an assistant in the performance of additional procedure(s), other than those reported with the modifier 62, during the same surgical session, those services may be reported using separate procedure code(s) with modifier 80 or modifier 82 added, as appropriate.
78 Unplanned return to the operating/procedure room by the same physician or other qualified health care professional following initial procedure for a related procedure during the postoperative period: it may be necessary to indicate that another procedure was performed during the postoperative period of the initial procedure (unplanned procedure following initial procedure). when this procedure is related to the first, and requires the use of an operating/procedure room, it may be reported by adding modifier 78 to the related procedure. (for repeat procedures, see modifier 76.)
79 Unrelated procedure or service by the same physician or other qualified health care professional during the postoperative period: the individual may need to indicate that the performance of a procedure or service during the postoperative period was unrelated to the original procedure. this circumstance may be reported by using modifier 79. (for repeat procedures on the same day, see modifier 76.)
80 Assistant surgeon: surgical assistant services may be identified by adding modifier 80 to the usual procedure number(s).
82 Assistant surgeon (when qualified resident surgeon not available): the unavailability of a qualified resident surgeon is a prerequisite for use of modifier 82 appended to the usual procedure code number(s).
AS Physician assistant, nurse practitioner, or clinical nurse specialist services for assistant at surgery
CR Catastrophe/disaster related
GC This service has been performed in part by a resident under the direction of a teaching physician
GV Attending physician not employed or paid under arrangement by the patient's hospice provider
LT Left side (used to identify procedures performed on the left side of the body)
Q6 Service furnished under a fee-for-time compensation arrangement by a substitute physician or by a substitute physical therapist furnishing outpatient physical therapy services in a health professional shortage area, a medically underserved area, or a rural area
RT Right side (used to identify procedures performed on the right side of the body)
XS Separate structure, a service that is distinct because it was performed on a separate organ/structure
XU Unusual non-overlapping service, the use of a service that is distinct because it does not overlap usual components of the main service
Date
Action
Notes
2002-01-01 Changed Code description changed.
1994-01-01 Added First appearance in code book in 1994.
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