66820

🩺CPT 65820: Goniotomy

Code Overview

CPT 65820 describes goniotomy — an intraocular angle surgery performed by an ab interno (from within) approach in which the trabecular meshwork is incised and/or excised over an extensive arc of the anterior chamber angle (at least 90 degrees, typically 180 degrees) to create a direct opening into Schlemm’s canal, thereby bypassing the obstructed trabecular meshwork and restoring aqueous outflow. It is classified as a major surgical procedure with a 90-day global period — the most significant procedural distinction separating it from minor procedures in the anterior chamber family.

CPT 65820 is the designated code for trabeculotomy ab interno, which is synonymous with goniotomy. It is the primary surgical treatment for congenital glaucoma (Q15.0) and is also employed in juvenile open-angle glaucoma, uveitic glaucoma, and select adult-onset angle-obstruction conditions. The code carries a nuanced and consequential NCCI bundling landscape that makes it one of the most compliance-critical codes in glaucoma surgery billing — particularly in the context of the expanding MIGS (micro-invasive glaucoma surgery) device market.

Critical distinction — goniotomy vs. MIGS goniotomy vs. goniopuncture: CPT 65820 is reserved for extensive trabecular meshwork incision of at least 3 clock hours (90 degrees minimum) performed with a goniotomy knife, blade, or equivalent instrument via an ab interno gonioscopic approach. It does not apply to: (1) simple goniopuncture (a few needle punctures without appreciable meshwork incision); (2) minimal or incidental trabecular incision performed as part of a MIGS device insertion (66989, 66991, 0671T); or (3) any limited viscoelastic canal injection. Misapplication of 65820 to MIGS goniotomy device cases is the most frequently cited compliance issue with this code.

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Full Code Description

Element	Detail
CPT Code	65820
Full Descriptor	Goniotomy
Section	Incision Procedures on the Anterior Chamber (65800-65880)
System	Eye and Ocular Adnexa
Global Period	090 — Major surgery; 90 postoperative days
Separate Procedure	No
wRVU	~7.69
Facility Total RVU	~23.50
Non-Facility Total RVU	~23.80
Assistant Surgeon	Not allowed
Bilateral	Per eye — use -RT/-LT; -50 for bilateral same session
Add-On Eligible	Yes — +66990 (ophthalmic endoscope) if endoscopy used
ASC Eligible	Yes — eligible for ASC facility fee
HOPD APC	APC 5492, J1 indicator — comprehensive APC; multiple procedure rules do NOT apply in HOPD
Medicare ~Payment (2025)	~$855-$870 (physician; geographically adjusted)
ASC Facility Fee (approx.)	~$1,960-$2,050
HOPD Facility Fee (approx.)	~$4,000-$4,100
Anesthesia	00145 (eye procedures NOS); 00142 (lens/anterior segment) for pediatric general anesthesia
Valid FY	FY2025

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Clinical Description

Anatomy of the Anterior Chamber Angle

The anterior chamber angle (iridocorneal angle) is the peripheral circumferential zone of the anterior segment where the iris meets the inner surface of the cornea. It is the critical aqueous drainage region of the eye, containing the trabecular meshwork, Schlemm’s canal, and their associated outflow structures.

Trabecular Meshwork (TM):
The TM is a sponge-like, multi-layered filtering tissue spanning the anterior chamber angle. It is divided into three layers from inside out:

• Uveal meshwork — innermost; large pores; loose arrangement; faces the anterior chamber

• Corneoscleral meshwork — middle layer; largest component; sheet-like lamellae with decreasing pore size moving outward; the layer through which most aqueous filtration occurs

• Juxtacanalicular (cribriform) meshwork — outermost; extracellular matrix-rich layer immediately adjacent to Schlemm’s canal inner wall; site of highest aqueous outflow resistance; most clinically relevant layer in open-angle glaucoma pathophysiology

Schlemm’s Canal:
An annular vascular channel (approximately 190-370 μm diameter) located at the corneoscleral junction, circumferentially surrounding the limbus. The inner wall of Schlemm’s canal is in direct apposition with the juxtacanalicular meshwork. Aqueous enters Schlemm’s canal through pores (transendothelial channels, “giant vacuoles”) in its inner wall endothelium, then flows through 25-35 collector channels into the deep scleral plexus and episcleral veins.

Barkan’s Membrane:
In congenital glaucoma (primary congenital glaucoma, PCG), an abnormal imperforate membrane — described by Otto Barkan, MD — covers the trabecular meshwork, physically blocking aqueous outflow. This membrane is a developmental anomaly of the anterior chamber angle in which the normal maturation of the angle tissues (migration of the neural crest cells that form the angle structures) is arrested or abnormal. Goniotomy (CPT 65820) was originally developed specifically to incise Barkan’s membrane and restore normal aqueous drainage — hence the historical term “Barkan membrane surgery.”

Gonioscopy — visualization prerequisite:
Because the anterior chamber angle cannot be directly visualized with standard optics (total internal reflection prevents direct view), gonioscopy (using a specialized contact lens — goniolens — that optically eliminates total internal reflection) is required to visualize the angle structures. Goniotomy is performed under direct gonioscopic visualization — the goniotomy knife must be introduced into the anterior chamber through a clear cornea and directed precisely toward the trabecular meshwork under real-time gonioscopic observation. This technique requires:

• Clear enough cornea to permit adequate visualization (cloudy cornea is a contraindication to goniotomy, favoring trabeculotomy ab externo in those cases)

• A cooperative or appropriately anesthetized patient

• An anterior segment with visible angle landmarks (pigmented trabecular meshwork, Schwalbe’s line, iris root, scleral spur)

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What CPT 65820 Specifically Requires

Based on the CPT 2022 Assistant article titled “Minimally Invasive Glaucoma Surgery,” CGS Medicare Coding Clarification, and AAO coding guidelines, CPT 65820 requires ALL of the following:

1. Extensive trabecular meshwork incision — the TM is incised and/or excised over an arc of at least 3 clock hours (90 degrees) and typically 180 degrees of the circumference of the angle; minimal or incidental incision is insufficient

2. Ab interno approach — the procedure is performed from within the anterior chamber using a surgical instrument introduced through a corneal paracentesis or a clear-corneal incision; this is the fundamental anatomical approach that distinguishes goniotomy from trabeculotomy ab externo (CPT 65850, which is an external approach)

3. Direct gonioscopic visualization — a goniolens is used to directly visualize the angle and guide the instrument

4. Goniotomy knife, blade, or equivalent cutting instrument — the trabecular meshwork is physically incised or excised; a simple needle puncture (goniopuncture) without appreciable tissue removal does not constitute goniotomy

Note

AAO-defined 65820 criterion: The operative report must specifically describe: (a) trabecular meshwork incision opening for the desired area — usually 180 degrees; (b) the instrument used (goniotomy knife, MST TRAB360, KDB Kahook Dual Blade, or other cutting instrument); (c) gonioscopic visualization used during the procedure; and (d) confirmation of opening into Schlemm’s canal.

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Primary Indication — Congenital Glaucoma (Q15.0)

Primary congenital glaucoma (PCG) — also called primary infantile glaucoma, buphthalmos, or hydrophthalmos — is the quintessential indication for CPT 65820 and the condition for which goniotomy was developed. PCG results from an isolated developmental anomaly of the anterior chamber angle (most commonly attributed to incomplete regression of the primordial endodermal tissue covering the anterior face of the trabecular meshwork — Barkan’s membrane — or to anomalous neural crest cell differentiation in the angle) in the absence of other ocular or systemic anomalies.

Epidemiology:

• Incidence: approximately 1 in 10,000-20,000 live births

• Bilateral in approximately 65-80% of cases

• More common in males (~65%) and in consanguineous populations

• Autosomal recessive inheritance in a subset; CYP1B1 gene mutations identified in familial cases

Pathophysiology:
Aqueous outflow resistance is pathologically elevated because the trabecular meshwork — and specifically Barkan’s membrane — physically obstructs flow into Schlemm’s canal. IOP rises above the threshold tolerated by the developing eye, causing:

• Buphthalmos — “ox eye”; the neonatal and infant eye globe is distensible and enlarges in response to elevated IOP; the globe stretches, causing increased axial length, corneal diameter expansion (megalocornea), and thinning of the sclera

• Haab’s striae — breaks in Descemet’s membrane from the stretching; appear as horizontal or curvilinear opaque lines in the cornea; pathognomonic for congenital glaucoma

• Corneal edema — from elevated IOP and endothelial stress; causes the classic “steamy cornea” appearance and is the primary cause of photophobia and blepharospasm in affected infants

• Optic nerve damage — cupping and atrophy from elevated IOP; may be partially reversible in early infancy if IOP is normalized

Classic triad of PCG:

1. Epiphora (excessive tearing)

2. Photophobia (light sensitivity — from corneal edema)

3. Blepharospasm (involuntary lid closure — also from corneal edema and light sensitivity)

Surgical approach:
The AAO guidelines state that surgical treatment is the primary therapy for PCG — medications are only temporizing bridges to surgery. The two primary surgical options are:

• Goniotomy (CPT 65820) — preferred when the cornea is clear enough to permit adequate gonioscopic visualization of the angle

• Trabeculotomy ab externo (CPT 65850) — preferred when corneal opacity prevents gonioscopic visualization, as it does not require angle visualization (the trabeculotomy probe is passed through Schlemm’s canal from an external scleral approach)

Note

Success rates for goniotomy in PCG are approximately 70-85% for IOP control with a single procedure; multiple goniotomies may be performed if needed. Outcomes are generally better when surgery is performed earlier (within the first year of life) and when the IOP elevation is not too severe at presentation.

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Secondary Indications for CPT 65820

Juvenile Open-Angle Glaucoma (JOAG)

JOAG is open-angle glaucoma with onset between ages 3-35 years, characterized by markedly elevated IOP, thin corneas, strong hereditary component (MYOC gene mutations), and rapid progression without treatment. The anterior chamber angle is anatomically open but functionally impaired (typically graded as trabecular dysfunction). Goniotomy can be effective in JOAG when the trabecular meshwork is the primary site of resistance, particularly in patients who have failed or are intolerant of medical management.

Uveitic Glaucoma

Glaucoma secondary to chronic intraocular inflammation — most commonly in:

• Juvenile idiopathic arthritis (JIA)-associated uveitis — the most common cause of uveitic glaucoma in children

• HLA-B27-associated uveitis (ankylosing spondylitis, reactive arthritis)

• Sarcoid uveitis

• Idiopathic chronic anterior uveitis

The mechanism of IOP elevation in uveitic glaucoma is multifactorial:

• Inflammatory trabecular meshwork obstruction — white blood cells, fibrin, and inflammatory debris clog the TM

• Trabecular meshwork scarring and fibrosis — chronic inflammation produces progressive TM dysfunction

• Anterior synechiae — peripheral anterior synechiae (PAS) may reduce the functional drainage area

• Steroid-induced IOP elevation — exacerbating factor in patients on chronic topical or systemic steroids for uveitis management

Goniotomy in uveitic glaucoma:

• Mechanically disrupts the obstruction to outflow at the level of the TM

• Works best when the angle is open and the inflammatory TM obstruction is the primary mechanism

• Less effective in eyes with dense PAS (secondary angle closure from uveitis), where filtering surgery (trabeculectomy, tube shunt) may be more appropriate

• Success rates are lower than in PCG (~50-70% for sustained IOP control) but can be meaningful as a joint-preservation approach in young patients who need to defer major filtering surgery

Aniridia-Associated Glaucoma

Aniridia (Q13.1) — congenital absence or near-absence of the iris — is associated with a progressive form of glaucoma that typically develops in the second or third decade of life. The mechanism involves:

• Aniridia-related keratopathy — pannus formation progressing across the cornea from the limbus

• Progressive scarring and closure of the anterior chamber angle from the advancing fibrovascular tissue

• Goniotomy may be performed early in the course when the angle is still partially open to preserve outflow before complete angle closure occurs

Steroid-Induced Glaucoma with Trabecular Meshwork Obstruction

In patients with steroid-induced IOP elevation (from topical, periocular, intravitreal, or systemic steroids) where the trabecular meshwork is the primary site of corticosteroid-induced dysfunction (downregulation of matrix metalloproteinases → excessive extracellular matrix accumulation in TM pores), goniotomy can mechanically clear the obstructed TM. This is particularly applicable when the steroid cannot be discontinued.

Secondary Angle-Obstruction Glaucoma

Selected cases of open-angle glaucoma where gonioscopy reveals trabecular meshwork obstruction by:

• Pigment (pigment dispersion syndrome — PDS; pigmentary glaucoma)

• Pseudoexfoliative material (pseudoexfoliation glaucoma — though scleral-based procedures are often preferred)

• Ghost cell glaucoma (erythrocyte ghosts obstructing TM after vitreous hemorrhage)

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Contraindications to Goniotomy

Contraindication	Reason
Cloudy/opaque cornea	Gonioscopic visualization of the angle is inadequate; substitute: trabeculotomy ab externo (65850)
Active neovascularization of the angle (NVA)	Neovascular tissue bleeds severely with incision; goniotomy risks catastrophic hyphema; filtering surgery or cyclophotocoagulation preferred
Angle dysgenesis (Axenfeld-Rieger, Peters’ anomaly)	Structural angle abnormalities with absent or dysgenetic trabecular landmarks; goniotomy success is poor
Dense peripheral anterior synechiae (PAS)	Angle closure from PAS cannot be effectively reversed by trabecular incision alone
Poor patient cooperation (without anesthesia)	Fine intraocular surgery requires complete patient stillness; general anesthesia is used for infants and young children
Absence of angle pigmentation (in adults)	Reduces ability to identify TM landmarks reliably for accurate knife placement
Very advanced buphthalmos with thin sclera	Highly distended eyes have altered anatomy; surgical complexity significantly increased

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Technique Description

Instrument options:

• Traditional goniotomy knife (Wheeler knife, Worst-type goniotome) — a custom-designed blade with a fine cutting edge and a long handle permitting entry through the opposite limbus

• Kahook Dual Blade (KDB) — a specialized dual-bladed instrument designed to excise a strip of trabecular meshwork; the dual blades create an incision and simultaneously excise the tissue between them; widely used in modern goniotomy

• MST TRAB360 — a viscoelastic-assisted system; a flexible probe passed through the TM for 360-degree circumferential trabeculotomy using a suture passed around the circumference of Schlemm’s canal

• OMNI Surgical System — a combined cannulation + viscoelastic + trabeculotomy device; when used for the trabeculotomy (goniotomy) component, CPT 65820 is appropriate; when the cannulation and viscoelastic injection alone are performed without the trabeculotomy, CPT 66999 or 66174 applies

• Trabectome — electrocautery-based ab interno TM ablation device; CPT 65820 has been used for Trabectome cases historically, though some sources use 65850; follow current payer guidance for Trabectome-specific coding

• Ophthalmic endoscope — if the ophthalmic endoscope is used during goniotomy, add +66990 (ophthalmic endoscope; add-on code; eligible for use with 65820; not subject to multiple procedure payment reduction)

Operative technique (traditional goniotomy knife approach):

1. Anesthesia: General anesthesia in pediatric patients (neonates, infants, young children); topical and/or sub-Tenon’s anesthesia in cooperative adolescents and adults. The eye is paralyzed (no motion) to allow precise introcular instrument control.

2. Patient positioning: Standard supine OR table position; microscope focused on the operative eye.

3. Draping and speculum placement: Standard ophthalmic draping; wire speculum or adjustable lid speculum placed.

4. Goniolens placement: A surgical goniolens (Swan-Jacob, Barkan, Koeppe, or similar) is placed on the cornea, filled with viscoelastic or coupling solution (methylcellulose, BSS). The goniolens eliminates total internal reflection and allows direct visualization of the anterior chamber angle under the operating microscope at the required magnification. The view is from above; the surgeon must tilt the head/microscope or the patient’s head to align the angle into view.

5. Corneal entry: The goniotomy knife is introduced through a clear corneal incision at the temporal limbus (opposite to the angle being treated), directed across the anterior chamber toward the nasal angle. The entry is made at approximately 10 o’clock in the right eye (or 2 o’clock in the left eye) to allow the blade to approach the inferior nasal trabecular meshwork.

6. Trabecular meshwork engagement: Under gonioscopic visualization, the knife tip is advanced to the trabecular meshwork. The surgeon identifies the:

   • Schwalbe’s line — the most anterior landmark; the termination of Descemet’s membrane

   • Trabecular meshwork — the slightly grayish-tan filtering band just posterior to Schwalbe’s line; pigmented TM is brown; in PCG, appears as Barkan’s membrane

   • Scleral spur — the posterior boundary of the TM; a white line

   • Iris root — the most posterior angle structure

7. Incision: The knife is used to incise the trabecular meshwork in a sweeping motion, advancing along the desired arc. For pediatric congenital glaucoma, the standard incision spans 180 degrees (6 clock hours) — typically the nasal 180 degrees. The knife tip sweeps through the TM at the level of the corneoscleral meshwork, creating an opening that communicates with Schlemm’s canal. The characteristic finding of successful incision is a slight bleed-back of blood from Schlemm’s canal, confirming the canal has been entered.

8. Anterior chamber maintenance: Throughout the procedure, the anterior chamber is maintained with viscoelastic or BSS. Loss of the chamber causes the angle to collapse and the incision to be imprecise.

9. Instrument withdrawal and wound closure: The goniotomy knife is withdrawn. The clear corneal entry wound is typically self-sealing (corneal architecture provides the valve). BSS or viscoelastic is used to reform the chamber if needed.

10. Postoperative medications: Topical steroid (prednisolone acetate 1% or difluprednate), topical antibiotic, and cycloplegic as needed. IOP-lowering medications are continued or adjusted based on post-operative IOP response.

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90-Day Global Period — Clinical Implications

CPT 65820 carries a 90-day global period — the standard major surgery global period. This has the following billing implications:

Service Category	Included in Global (Cannot Bill Separately)	Separately Billable
Pre-operative visits	Day of decision to operate and all pre-op care within 1 day before surgery included	Visits unrelated to goniotomy; visits more than 1 day before decision
Intraoperative services	All surgical care	—
Post-operative E/M	All routine post-op visits within 90 days	Post-op visits for NEW, unrelated problems (Modifier -24)
Post-op complications	Management of routine complications (without return to OR)	Return to OR for complication — Modifier -78
Repeat goniotomy	If repeat goniotomy required same eye within 90 days — Modifier -78 required	Second eye goniotomy (different eye) — bill separately

Combined Goniotomy with Cataract Surgery

CPT 65820 combined with cataract extraction (66984 or 66982) in the same session on the same eye is one of the most clinically significant combined procedure billing scenarios for 65820:

CPT Combination	Bundled?	Notes
65820 + 66984 (routine cataract)	NOT bundled — both separately billable	Most common combined MIGS-era scenario; each code billed separately; multiple procedure rules apply
65820 + 66982 (complex cataract)	NOT bundled — both separately billable	Less common; same billing rules
65820 + 66989 (cataract + MIGS stent, complex)	CANNOT separately report 65820 — LCD restriction	When a MIGS stent (e.g., iStent, Hydrus) is inserted, 66989 is the applicable code; 65820 is subsumed and not separately reportable
65820 + 66991 (cataract + MIGS stent, routine)	CANNOT separately report 65820 — LCD restriction	Same restriction
65820 + 66174 (canaloplasty without stent)	CANNOT separately report together — mutually exclusive	CPT Assistant explicitly prohibits this combination; NCCI edit; no override

Note

Multiple procedure payment reduction for 65820 + 66984: When goniotomy (65820) and cataract (66984 or 66982) are performed together on the same eye in the same session, both are separately reportable. The higher-valued procedure receives 100% of the allowed amount; the lower-valued procedure receives 50%. Goniotomy (wRVU ~7.69) and complex cataract (wRVU ~10.98) — in this combination, cataract is typically the higher value; 65820 would be paid at 50%. In an ASC, the facility payment is also subject to this 50% reduction for the second procedure.

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CPT Code Tree — Anterior Chamber / Angle Surgery Family

Eye and Ocular Adnexa — Anterior Segment
  └── Incision Procedures on the Anterior Chamber (65800-65880)
        │
        ├── 65800    Paracentesis, anterior chamber; aqueous removal
        │            (Emergency IOP reduction, CRAO, diagnostic tap — 0-day global)
        ├── 65810    Paracentesis; vitreous/anterior hyaloid removal (0-day global)
        ├── 65815    Paracentesis; blood removal, hyphema (0-day global)
        │
        ├── 65820    Goniotomy    ◄ THIS CODE
        │            (Ab interno TM incision ≥90°; trabeculotomy ab interno; 90-day global)
        │            → +66990: Ophthalmic endoscope (add-on, if used with 65820)
        │
        ├── 65850    Trabeculotomy ab externo
        │            (External approach; Schlemm's canal found externally; for cloudy cornea;
        │             90-day global)
        ├── 65855    Trabeculoplasty by laser surgery (SLT, ALT; 1+ sessions, same eye;
        │            0-day global)
        ├── 65860    Severing adhesions, anterior segment; laser technique
        ├── 65865    Severing adhesions; incisional, goniosynechialysis (separate procedure)
        ├── 65870    Severing adhesions; anterior synechiae except goniosynechiae (sep. proc.)
        └── 65880    Severing adhesions; posterior synechiae

Fistulization/Filtering Surgery (bundled with 65820 — require Modifier 59 to unbundle):
        ├── 66150    Fistulization; trephination with iridectomy
        ├── 66155    Fistulization; thermocauterization with iridectomy
        ├── 66160    Fistulization; sclerectomy with punch/scissors, with iridectomy
        ├── 66170    Trabeculectomy ab externo, no prior surgery
        └── 66172    Trabeculectomy ab externo with scarring

Aqueous Canal Surgery (critical for 65820 NCCI policy):
        ├── 66174    Transluminal dilation, without retention — MUTUALLY EXCLUSIVE with 65820
        ├── 66175    Transluminal dilation, with retention/stent — NCCI bundled with 65820
        ├── 66179    Aqueous shunt, without graft (tube shunt)
        ├── 66180    Aqueous shunt, with graft
        └── 66183    Anterior segment aqueous drainage device (ExPRESS)

MIGS — trabecular stent (CANNOT report 65820 separately with these):
        ├── 66989    Cataract, complex + trabecular bypass stent
        ├── 66991    Cataract, routine + trabecular bypass stent
        └── 0671T    Aqueous drainage device, without concurrent cataract

Ciliary Body Destruction (bundled with 65820; Modifier 59 override available):
        ├── 66710    TSCPC — transcleral cyclophotocoagulation
        └── 66711    ECP — endoscopic cyclophotocoagulation

Add-On Code for 65820:
        └── +66990   Use of ophthalmic endoscope (add-on; only valid with specific host codes
                     including 65820; not subject to multiple procedure reduction)

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Includes / Excludes Notes

What Is Included in CPT 65820

• Creation of the corneal entry wound (paracentesis wound for knife introduction)

• Gonioscopic examination at the time of surgery (surgical gonioscopy)

• Incision and/or excision of the trabecular meshwork over the documented arc (≥90 degrees)

• Entry into Schlemm’s canal

• Anterior chamber reformation (BSS/viscoelastic)

• Wound closure (typically self-sealing)

• Standard immediate post-operative care within the 90-day global period

What Is NOT Included (May Be Separately Reported)

• Ophthalmic endoscopy — if the ophthalmic endoscope is used during goniotomy, add +66990 (add-on code; not subject to multiple procedure reduction; adds to the physician’s reimbursement)

• Concurrent cataract extraction (66982, 66984) — separately reportable; not bundled with 65820

• Concurrent vitreoretinal procedures (67036 PPV, etc.) — separately reportable if performed for a separate indication

• Anesthesia services — separately billed by the anesthesia provider (00145 or 00142)

• Post-operative visits for new, unrelated problems — Modifier -24 required

Specific Procedures That CANNOT Be Separately Reported With 65820

Mutually exclusive — no override modifier possible:

Code	Description	Reason
66174	Transluminal dilation of aqueous canal, without stent	CPT Assistant explicitly states these cannot be reported together; NCCI enforces; the procedures are redundant on the same drainage pathway
66989	Cataract extraction, complex + trabecular bypass stent	Per CMS LCD L38233 and billing article — when a trabecular bypass MIGS stent is inserted, the goniotomy component is incidental and not separately coded
66991	Cataract extraction, routine + trabecular bypass stent	Same LCD restriction
0671T	Aqueous drainage device, without concurrent cataract	Same principle — device insertion subsumes the goniotomy component

Bundled — Modifier 59/X-modifier can override when separate clinical justification exists:

Code	Description	Modifier Override?
66150	Fistulization, trephination with iridectomy	Yes — Modifier 59 with documentation
66155	Fistulization, thermocauterization with iridectomy	Yes
66160	Fistulization, sclerectomy with punch/scissors + iridectomy	Yes
66170	Trabeculectomy ab externo, no prior surgery	Yes — if truly separate surgical intent and documented separately
66172	Trabeculectomy ab externo with scarring	Yes
66175	Transluminal dilation with stent retention	Yes — though CPT Assistant guidance discourages combining
66184	Revision aqueous shunt without graft	Yes
66185	Revision aqueous shunt with graft	Yes
66710	TSCPC — transcleral cyclophotocoagulation	Yes
66711	ECP — endoscopic cyclophotocoagulation	Yes
66762	Iridoplasty by photocoagulation	Yes
66987	Cataract complex with ECP	Yes
66988	Cataract routine with ECP	Yes

Note

Clinical note on 65820 + 66170 (goniotomy + trabeculectomy): While NCCI bundles these with a Modifier 59 override, combining goniotomy and trabeculectomy on the same eye in the same session is an unusual and uncommon surgical strategy. When it does occur (e.g., as part of a staged combined procedure in a complex pediatric glaucoma case), robust operative documentation of the distinct clinical rationale for each procedure is essential.

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HCC (Hierarchical Condition Category) Mapping

CPT 65820 itself carries no HCC value — HCC mapping applies to ICD-10-CM diagnosis codes.

Commonly Paired ICD-10-CM	Description	HCC Mapping
Q15.0	Congenital glaucoma	Not HCC mapped
H40.1110	Primary open-angle glaucoma, right eye, mild stage	Not HCC mapped
H40.1120	Primary open-angle glaucoma, left eye, mild stage	Not HCC mapped
H40.40X0	Glaucoma secondary to eye inflammation, unspecified	Not HCC mapped
H40.2210	Chronic angle-closure glaucoma, right eye	Not HCC mapped
M08.01	JIA, right shoulder (underlying JIA for uveitic glaucoma)	Not HCC mapped
E10.39	Type 1 diabetes with other diabetic eye disease	HCC 18
E11.39	Type 2 diabetes with other diabetic eye disease	HCC 19
H40.3110	Glaucoma secondary to trauma, right eye	Not HCC mapped
Q13.1	Aniridia	Not HCC mapped
B00.51	Herpesviral iridocyclitis	Not HCC mapped

Note

No glaucoma diagnosis currently maps to CMS-HCC: In the current CMS-HCC risk adjustment model (V28), glaucoma diagnoses (H40.-) do not carry HCC weight. However, the systemic conditions that cause secondary glaucoma — diabetes (E10/E11), autoimmune disease (JIA — M08.-), and other systemic comorbidities — do carry HCC weight. Thorough documentation and coding of all concurrent systemic conditions with ocular manifestations is critical for complete risk adjustment.

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MS-DRG Mapping (Inpatient)

CPT 65820 is overwhelmingly performed in the outpatient ASC or HOPD setting. Inpatient admission is rare and typically limited to complex pediatric cases requiring general anesthesia with multi-day monitoring (severe buphthalmos, prematurity, systemic comorbidity) or combined procedures with significant surgical risk.

CC/MCC Status of Paired Diagnoses

ICD-10-CM	Description	CC/MCC Status
Q15.0	Congenital glaucoma	Not CC/MCC (but PDx in pediatric admission)
H40.40X0	Glaucoma sec. to eye inflammation	Not CC/MCC
H40.3110	Glaucoma secondary to trauma	Not CC/MCC
H44.011	Panophthalmitis (if concurrent)	MCC
H44.001	Purulent endophthalmitis (if concurrent)	CC

Inpatient DRG Groups (When Admitted)

MS-DRG	Description	Trigger
116	Intraocular Procedures with CC/MCC	Goniotomy performed inpatient + CC or MCC secondary diagnosis
117	Intraocular Procedures without CC/MCC	Goniotomy performed inpatient; no CC or MCC
124	Other Disorders of the Eye with MCC or Thrombolytic Agent	If admitted without OR-level procedure
125	Other Disorders of the Eye without MCC	Medical admission for glaucoma management

MDC: MDC 02 — Diseases and Disorders of the Eye

ASC vs. HOPD Reimbursement Distinction

Setting	Multiple Procedure Rule	Notes
ASC	Applies — 50% reduction on lower-valued procedure when combined with another major procedure	When 65820 + 66984 (cataract) performed same session: higher-valued procedure at 100%; lower at 50%
HOPD	Does NOT apply — J1 comprehensive APC	Goniotomy (APC 5492, J1 status) packages all covered Part B services on the claim; multiple procedure reduction is not applied in HOPD; total reimbursement is from the single APC

Note

ASC vs. HOPD strategic consideration: For combined cataract + goniotomy cases, the HOPD’s comprehensive APC packaging (no multiple procedure reduction) typically yields higher total facility reimbursement than the ASC setting (where the second procedure is reduced by 50%). For physicians and facilities performing high volumes of combined cataract + goniotomy cases, HOPD may provide superior facility reimbursement — though site-of-service considerations involve many factors beyond reimbursement.

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ICD-10-CM Diagnosis Codes Commonly Paired With CPT 65820

Congenital Glaucoma — Pediatric Primary Indication

ICD-10-CM	Description	Notes
Q15.0	Congenital glaucoma	Primary PDx for PCG/goniotomy; includes buphthalmos
H40.10X0	Open-angle glaucoma, unspecified, stage unspecified	When PCG manifests as open-angle pattern; also JOAG
H40.1110	Primary open-angle glaucoma, right eye, mild	JOAG right
H40.1120	Primary open-angle glaucoma, left eye, mild	JOAG left
H40.1130	Primary open-angle glaucoma, bilateral, mild	Bilateral JOAG

Note

Q15.0 coding specifics: Q15.0 is classified under Chapter 17 (Congenital Malformations). It includes all forms of congenital glaucoma — primary, infantile, and buphthalmos as a manifestation. No laterality is embedded within Q15.0 itself; use Modifier -RT/-LT/-50 to specify laterality on the CPT code.

Open-Angle and Secondary Glaucoma — Adult and Adolescent Indications

ICD-10-CM	Description	Notes
H40.1111	Primary open-angle glaucoma, right eye, mild stage	6th character: 0=unspec, 1=mild, 2=mod, 3=severe, 4=indet
H40.1121	Primary open-angle glaucoma, left eye, mild stage
H40.1131	Primary open-angle glaucoma, bilateral, mild stage
H40.40X0	Glaucoma secondary to eye inflammation, unspecified eye	Uveitic glaucoma
H40.40X1	Glaucoma secondary to eye inflammation, right eye
H40.40X2	Glaucoma secondary to eye inflammation, left eye
H40.3110	Glaucoma secondary to trauma, right eye, stage unsp	Post-traumatic; ghost cell glaucoma
H40.3120	Glaucoma secondary to trauma, left eye, stage unsp
H40.5110	Glaucoma secondary to other eye disorders, right eye	PDS, pigmentary glaucoma
H40.5120	Glaucoma secondary to other eye disorders, left eye
H40.051	Ocular hypertension, right eye	When IOP elevation is primary concern without established glaucomatous damage
H40.052	Ocular hypertension, left eye

Aniridia

ICD-10-CM	Description	Notes
Q13.1	Aniridia	Congenital iris absence; associated progressive angle obstruction; goniotomy for early-stage aniridia glaucoma

Uveitis as Underlying Cause

ICD-10-CM	Description	Notes
M08.011	Juvenile idiopathic arthritis, right shoulder	Use the JIA code to indicate systemic disease causing uveitic glaucoma
H20.011	Primary iridocyclitis, right eye	Active uveitis driving uveitic glaucoma
H20.012	Primary iridocyclitis, left eye
M32.9	Systemic lupus erythematosus, unspecified	Underlying connective tissue disease
D86.0	Sarcoidosis of lung	Systemic sarcoid with ocular involvement

Chronic Angle-Closure Glaucoma (Selected Cases)

ICD-10-CM	Description	Notes
H40.2210	Chronic angle-closure glaucoma, right eye, unspec stage	In select cases where angle closure is from TM obstruction amenable to goniotomy
H40.2220	Chronic angle-closure glaucoma, left eye, unspec stage

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Billing and Modifier Guidance

Laterality Modifiers — Mandatory

Modifier	Meaning	Application
-RT	Right eye	Always required on 65820
-LT	Left eye	Always required on 65820
-50	Bilateral procedure	If bilateral goniotomy performed in same session (both eyes); some MACs require two line items with -RT and -LT respectively

Modifier -51 — Multiple Procedures

When 65820 is performed with another major procedure (most commonly 66984 or 66982 cataract extraction):

• Report the higher-value procedure at 100% with no modifier

• Report 65820 with Modifier -51 (or the lower-value procedure with -51 depending on the pairing)

• Medicare and many payers apply a 50% payment reduction to the lesser-valued procedure

• In the ASC, the ASC facility fee is similarly subject to 50% reduction on the second procedure

• HOPD: Modifier -51 is not applicable — the J1 comprehensive APC packages everything

Modifier -59 / X-Modifiers — Distinct Procedural Service

For NCCI-bundled procedures where both are being performed for distinct clinical purposes at the same session (e.g., 65820 + 66170 in a complex pediatric case):

• Modifier -59 (or XE, XS, XP, XU as appropriate) is appended to the lower-value/bundled code

• Documentation must clearly support the clinical necessity of each procedure independently

• MAC-level review should be anticipated for uncommon code combinations

Modifier -78 — Unplanned Return to OR Within Global Period

If a patient requires repeat goniotomy (same eye) or other related intraocular procedure within the 90-day global period of the original 65820:

• Modifier -78 permits separate billing for the related procedure during the global period

• Payment is reduced to intraoperative component only (~70% of allowed amount)

• Document the clinical reason the repeat procedure was required

Modifier -79 — Unrelated Procedure During Post-Op Period

If an unrelated intraocular procedure is needed during the 90-day global period of 65820:

• Modifier -79 establishes the procedure as unrelated to the original goniotomy

• Documentation must confirm the new procedure addresses a distinct, unrelated condition

Modifier -24 — Unrelated E/M During Post-Op Period

If the patient is seen during the 90-day global period for a condition completely unrelated to the goniotomy:

• Modifier -24 appended to the E/M code establishes it is unrelated to the surgical global period

• Document the distinct, unrelated reason for the encounter

Add-On Code +66990 — Ophthalmic Endoscope

Code	Description	Notes
+66990	Use of ophthalmic endoscope (add-on)	When an intraocular endoscope is used during goniotomy; appended to 65820; not subject to multiple procedure reduction; adds approximately $70-100 to physician reimbursement

Note

+66990 eligibility: Not all CPT codes are eligible for +66990. CPT explicitly identifies 65820 as one of the codes with which +66990 may be reported. This add-on applies when a fiber-optic endoscope is introduced into the eye to provide endoscopic visualization during the surgical procedure — distinct from the standard gonioscopic visualization.

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Coding Examples

Example 1 — Primary Congenital Glaucoma, Infant, Bilateral Goniotomy Same Session

Clinical Scenario:
A 4-month-old male presents with bilateral buphthalmos, corneal edema, photophobia, and epiphora since birth. IOP under examination under anesthesia (EUA) is 38 mmHg OD and 34 mmHg OS. Corneas are mildly hazy but adequate for gonioscopic visualization. Angle examination confirms Barkan’s membrane bilaterally. The pediatric glaucoma specialist performs bilateral goniotomy (180-degree nasal arc each eye) under general anesthesia.

ICD-10-CM:

• Q15.0 — Congenital glaucoma (primary — reason for both procedures)

CPT:

• 65820-50 — Goniotomy, bilateral (Modifier -50 for bilateral same session)

Modifier -50 vs. RT/LT for bilateral procedures: Medicare and most MACs accept Modifier -50 reported on one line for bilateral eye procedures. Some payers prefer two separate lines with -RT and -LT respectively. Verify payer-specific bilateral billing requirements before submission.

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Example 2 — Juvenile Open-Angle Glaucoma, Goniotomy with KDB Right Eye

Clinical Scenario:
A 19-year-old male with severe JOAG OD has failed maximum medical therapy (four medications including dorzolamide-timolol, bimatoprost, brimonidine) and one prior SLT (CPT 65855). IOP remains 36 mmHg OD. His glaucoma specialist recommends goniotomy using the Kahook Dual Blade (KDB) for ab interno trabeculotomy. The surgeon documents “trabeculotomy ab interno using KDB, 180-degree nasal arc OD, gonioscopic visualization throughout, opening of Schlemm’s canal confirmed by blood reflux.”

ICD-10-CM:

• H40.1113 — Primary open-angle glaucoma, right eye, severe stage (PDx — JOAG driving the surgical intervention)

CPT:

• 65820-RT — Goniotomy, right eye

KDB goniotomy = 65820: The Kahook Dual Blade performs ab interno TM excision (trabeculectomy ab interno), which is the surgical equivalent of goniotomy. CPT 65820 is the appropriate code regardless of the specific instrument used, provided the documentation supports extensive TM incision as required.

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Example 3 — Combined Cataract Extraction and Goniotomy, Right Eye

Clinical Scenario:
A 72-year-old female with primary open-angle glaucoma OD (moderate stage) on three medications and visually significant cataract OD presents for combined cataract extraction and goniotomy. The surgeon performs phacoemulsification with IOL implantation (66984) followed by goniotomy (65820) using the OMNI surgical system’s trabeculotomy mode, opening 180 degrees of the nasal TM under gonioscopic visualization.

ICD-10-CM:

• H40.1112 — Primary open-angle glaucoma, right eye, moderate stage (glaucoma — PDx driver for 65820)

• H26.011 — Infantile and juvenile nuclear cataract (or appropriate cataract code — additional diagnosis driver for 66984)

CPT:

• 66984-RT — Extracapsular cataract removal, right eye (higher wRVU — 100% payment)

• 65820-RT-51 — Goniotomy, right eye (lower wRVU — 50% reduction, Modifier -51; not NCCI bundled with 66984)

Critical billing note: 65820 + 66984 are NOT bundled under NCCI. Both are separately billable. This is the most commonly performed combined procedure scenario for 65820 in adult glaucoma practice. The 50% multiple procedure reduction applies to the lower-value code (65820) in both the physician fee and ASC facility fee. In the HOPD, the J1 APC packages both services — the multiple procedure reduction does not apply.

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Example 4 — Uveitic Glaucoma, Goniotomy Left Eye, JIA Patient

Clinical Scenario:
A 14-year-old female with juvenile idiopathic arthritis (JIA) and chronic anterior uveitis OS has uveitic glaucoma OS refractory to maximum tolerated medical therapy. IOP is 32 mmHg OS on maximal drops. She is not on steroids. Gonioscopy shows open angle with TM debris and inflammatory material but no synechiae. Her glaucoma specialist performs goniotomy OS (180-degree superior arc) under general anesthesia using a traditional goniotomy knife.

ICD-10-CM:

• H40.40X2 — Glaucoma secondary to eye inflammation, left eye (primary — uveitic glaucoma driving the procedure)

• M08.00 — Juvenile rheumatoid arthritis, unspecified site (or more specific JIA subtype — additional; systemic cause of the uveitis)

• H20.012 — Primary iridocyclitis, left eye (additional — active uveitis context)

CPT:

• 65820-LT — Goniotomy, left eye

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Example 5 — Goniotomy + Endoscopic Cyclophotocoagulation — NCCI Bundled, Modifier 59 Required

Clinical Scenario:
A 45-year-old male with refractory glaucoma OU presents for staged bilateral procedures. Today, right eye treatment: the glaucoma specialist performs goniotomy (180-degree nasal arc OD) followed by endoscopic cyclophotocoagulation (ECP) of the ciliary processes OD in the same surgical session. These procedures address different mechanisms (TM outflow enhancement with goniotomy vs. aqueous production reduction with ECP). The surgeon provides distinct documentation for each.

ICD-10-CM:

• H40.1113 — Primary open-angle glaucoma, right eye, severe stage

CPT:

• 65820-RT — Goniotomy, right eye (primary; higher value)

• 66711-RT-59 — Endoscopic cyclophotocoagulation (ECP), right eye (bundled with 65820 per NCCI; Modifier -59 applied to unbundle; documentation supports distinct procedures with different mechanisms; the ECP is a separate instrument, separate target, and separate physiologic mechanism)

Modifier 59 justification: The NCCI bundles 65820 and 66711 with a “1” indicator (meaning unbundling IS allowed when justified). The clinical rationale must be clearly documented: goniotomy addresses trabecular outflow resistance; ECP addresses aqueous production at the ciliary body. These are distinct tissues, distinct mechanisms, and the procedures are not technically redundant. With distinct documentation, both can be separately reported using Modifier -59.

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Example 6 — Goniotomy with MIGS Stent Insertion — 65820 NOT Separately Reportable

Clinical Scenario:
A 68-year-old male with mild POAG OD and visually significant cataract OD undergoes combined phacoemulsification + iStent inject W insertion OD. As part of the iStent insertion, the surgeon introduces the iStent delivery device into the anterior chamber angle and inserts two stents through the trabecular meshwork. The provider queries whether 65820 can also be billed for the TM penetration associated with the iStent insertion.

ICD-10-CM:

• H40.1111 — Primary open-angle glaucoma, right eye, mild stage

• Appropriate cataract diagnosis

CPT:

• 66991-RT — Extracapsular cataract removal (routine) with insertion of ocular implant/stent into trabecular meshwork, right eye (the correct and only procedure code; includes the TM penetration for stent insertion)

• 65820 is NOT separately reportable — per CMS LCD L38233, the trabecular puncture/incision performed as part of inserting an aqueous drainage device is incidental to and included in the device insertion code (66991); 65820 cannot be separately billed regardless of the instrument used for TM penetration

Most common compliance risk with 65820: Attempting to report 65820 in addition to 66989, 66991, or 0671T is the most frequently cited inappropriate use of goniotomy coding and a known MAC audit target. When a MIGS stent is inserted, the goniotomy component is definitionally subsumed into the MIGS procedure code. This applies regardless of whether the surgeon used a KDB, MST TRAB360, OMNI, or other device for the TM entry.

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Example 7 — Repeat Goniotomy, Within Global Period, Modifier -78

Clinical Scenario:
A 6-month-old male underwent goniotomy OD (CPT 65820-RT) 6 weeks ago for PCG. His IOPs have been marginally controlled but remain elevated at 26 mmHg OD. His pediatric glaucoma specialist recommends repeat goniotomy OD (inferior 180 degrees this time, as the prior goniotomy addressed the nasal arc). The procedure is performed at week 6 — within the 90-day global period of the first 65820.

ICD-10-CM:

• Q15.0 — Congenital glaucoma

CPT:

• 65820-RT-78 — Goniotomy, right eye, Modifier -78 (unplanned return to OR for related procedure during 90-day global period; payment reduced to intraoperative component only)

Why -78 and not -76 (repeat procedure): Modifier -78 applies to unplanned returns to the OR for a related procedure during the global period of a prior surgery. Modifier -76 applies to an exact repeat of the same procedure by the same provider when it is expected or planned as part of the treatment plan. For staged goniotomies (which are commonly planned in advance for congenital glaucoma management), Modifier -76 may be more appropriate when the repeat procedure is pre-planned. Consult your MAC and payer guidelines — both -76 and -78 have been used in this context and payer acceptance varies.

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Key Coding Pitfalls & Tips

• 65820 requires extensive TM incision — at least 90 degrees (3 clock hours), typically 180 degrees. A simple goniopuncture (needle puncture without appreciable meshwork incision), a limited canal entry, or a minimal viscoelastic injection does not qualify for 65820. If the procedure does not meet this threshold, use 66999 (unlisted anterior segment procedure) and submit with a detailed cover letter explaining the procedure.

• 65820 + 66989/66991/0671T is never billable together. This is the most critical compliance point for 65820. When a trabecular bypass MIGS stent is inserted (iStent, Hydrus, etc.) as part of combined cataract surgery, 66989 or 66991 is the only reportable code. Adding 65820 for the TM penetration associated with the stent insertion is not permitted per CMS LCD.

• 65820 and 66174 are mutually exclusive — no Modifier 59 override. Unlike many NCCI bundles where Modifier 59 can unbundle procedures with justification, the 65820 + 66174 combination is prohibited by CPT Assistant instruction and NCCI regardless of clinical circumstances on the same eye at the same session.

• 65820 IS separately billable with 66984 and 66982 (cataract). The non-bundled status of goniotomy with standard cataract extraction codes (NOT MIGS-combined cataract codes) is one of the most frequently misunderstood aspects of glaucoma surgery billing. Combined phaco + goniotomy (without a MIGS stent) is a legitimate, separately-reportable combination.

• The 90-day global period applies to routine post-op visits. Unlike the 0-day global codes in the anterior chamber paracentesis family, 65820 carries a full 90-day major surgery global. Post-op visits, suture removal (if applicable), and routine glaucoma monitoring within 90 days are included in the global fee — they cannot be separately billed unless the visit addresses an unrelated problem (Modifier -24).

• +66990 ophthalmic endoscope is eligible for use with 65820. If the ophthalmic endoscope is used during goniotomy, add +66990. It is not subject to the 50% multiple procedure reduction (add-on codes are exempt from multiple procedure reductions). Verify the endoscope was used and document accordingly.

• Document “180 degrees,” “3+ clock hours,” or specific degree arc. The operative note must quantify the extent of the TM incision. Vague language like “goniotomy performed” without specifying the arc length is insufficient to support 65820 and may result in audit downcoding to 66999.

• HOPD comprehensive APC packages all services — no multiple procedure reduction. When combined cataract + goniotomy is performed in the HOPD, the J1 APC 5492 packages both services under one facility APC payment — there is no multiple procedure reduction in HOPD. This is the opposite of the ASC rule.

• Q15.0 does not carry laterality — the diagnosis is not lateralized within the code. Provide laterality through the CPT modifiers (-RT/-LT/-50) and document clearly in the clinical note.

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Related Codes (Cross-Reference)

Code	Type	Description
65850	CPT	Trabeculotomy ab externo — external approach; for cloudy corneas; 90-day global
65855	CPT	Trabeculoplasty by laser surgery (SLT, ALT); 0-day global
65800	CPT	Paracentesis, anterior chamber, aqueous removal; 0-day global
66170	CPT	Trabeculectomy ab externo, no prior surgery — filtering bleb surgery
66172	CPT	Trabeculectomy ab externo, with scarring — repeat filtering surgery
66174	CPT	Transluminal dilation, without stent — MUTUALLY EXCLUSIVE with 65820
66175	CPT	Transluminal dilation, with stent — NCCI bundled with 65820
66179	CPT	Aqueous shunt to extraocular reservoir (tube shunt) without graft
66180	CPT	Aqueous shunt with graft
66710	CPT	TSCPC — transcleral cyclophotocoagulation; NCCI bundled
66711	CPT	ECP — endoscopic cyclophotocoagulation; NCCI bundled
66984	CPT	Cataract extraction routine — NOT bundled with 65820
66982	CPT	Cataract extraction complex — NOT bundled with 65820
66989	CPT	Cataract + MIGS stent, complex — 65820 NOT separately reportable with
66991	CPT	Cataract + MIGS stent, routine — 65820 NOT separately reportable with
0671T	CPT	Aqueous drainage device without cataract — 65820 NOT separately reportable with
+66990	CPT	Ophthalmic endoscope add-on — eligible for use with 65820
66999	CPT	Unlisted anterior segment procedure — use when goniotomy does not meet 65820 criteria
Q15.0	ICD-10-CM	Congenital glaucoma — primary indication
H40.1110	ICD-10-CM	Primary open-angle glaucoma, right eye, stage unspecified
H40.1120	ICD-10-CM	Primary open-angle glaucoma, left eye, stage unspecified
H40.1130	ICD-10-CM	Primary open-angle glaucoma, bilateral, stage unspecified
H40.40X0	ICD-10-CM	Glaucoma secondary to eye inflammation, unspecified
H40.40X1	ICD-10-CM	Glaucoma secondary to eye inflammation, right eye
H40.40X2	ICD-10-CM	Glaucoma secondary to eye inflammation, left eye
H40.3110	ICD-10-CM	Glaucoma secondary to trauma, right eye, stage unspecified
H40.051	ICD-10-CM	Ocular hypertension, right eye
H40.052	ICD-10-CM	Ocular hypertension, left eye
Q13.1	ICD-10-CM	Aniridia — associated progressive angle obstruction glaucoma
H20.011	ICD-10-CM	Primary iridocyclitis, right eye (uveitic context)
H20.012	ICD-10-CM	Primary iridocyclitis, left eye
M08.00	ICD-10-CM	Juvenile idiopathic arthritis — systemic cause of uveitic glaucoma
Z96.1	ICD-10-CM	Presence of intraocular lens — if pseudophakic eye at time of goniotomy

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Last Reviewed: 2026-02-18 | Source: AMA CPT Professional Edition 2025, CMS MPFS 2025, CMS NCCI Policy Manual 2025, CGS Medicare Coding Clarification A65820, CMS LCD L38233 MIGS, Corcoran Consulting Group Goniotomy FAQ, AAO EyeWiki PCG, Glaucoma Physician Coding Guidance, AAPC Ophthalmology Coding Alert, ICD-10-CM FY2025