CALOTCholecystectomy Anatomy, Learning & Operative Technique Exam zone
The operation

Step-by-step operative technique

A standard sequence done the same way every time is the single best protection against the day the anatomy is not standard.

Latest source: SAGES Safe Cholecystectomy Program (accessed October 2026) · about 7 min read · how evidence is marked

Reviewed against its sources on 3 November 2026.

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Three things to remember
  1. Same sequence every time: position, four ports, fundus up and neck lateral, posterior peritoneum first, stay on the gallbladder wall.
  2. Clear the triangle from the gallbladder down until only two structures remain, then photograph the Critical View from both sides.
  3. No diathermy near the common duct, no clip on anything you cannot name, no blind clipping for bleeding.

01Principles before steps

Three rules that run through every step
  • Identify, then divide. Nothing is clipped or cut until the Critical View of Safety (CVS) is obtained and confirmed in two views.
  • Stay on the gallbladder. Dissection starts at the gallbladder wall and moves away from the bile duct, never toward it. The common duct does not need to be seen.
  • Stop when the plan stops working. If the triangle cannot be cleared, change to a bail-out.
Sources and a note on the photographs

The operation described here follows the six strategies of the SAGES Safe Cholecystectomy Program (SAGES) and the safe steps in Tokyo Guidelines 2018 (Wakabayashi et al., 2018). Guideline The operative photographs on this page are reproduced from two open-access reviews by Gupta and colleagues under the Creative Commons BY-NC 4.0 licence, with the source and figure number under each; the labelled schematics are original to this site. Your own unit’s recorded operations are the best companion to both.

02Positioning, team and equipment

Patient

Supine, arms tucked or on boards. Reverse Trendelenburg 15 to 20 degrees and left tilt 10 to 15 degrees once ports are in.

Pregnancy after 20 weeks: left lateral tilt throughout (pregnancy)

Team

American: surgeon on the patient’s left, camera operator to the surgeon’s left, monitor over the right shoulder. French: surgeon between the legs.

Neither is safer; use what your unit teaches

Scope

30-degree, 10 mm. The angle is what shows the back of the triangle and the cystic plate.

A 0-degree scope makes the doublet view difficult

Instruments

Two atraumatic graspers, Maryland, hook or spatula, 5 mm clip applier (medium-large clips, 6 to 8 mm), scissors, suction-irrigator, retrieval bag.

Available: 10 mm clips, endoloop or suture for a wide duct, needle-holder for subtotal

Imaging

Cholangiography catheter and fluoroscopy, or the indocyanine green (ICG) camera, in the room if your unit uses them.

ICG is given at the right time for your regimen: hours before, or a low dose at induction or during the operation (dose table on the ICG page); how to perform and read a cholangiogram

Checklist

WHO surgical safety checklist, antibiotic prophylaxis where indicated (indications).

A named plan for the difficult case

Positioning on the tableAI teaching illustration
Side view of a patient on an operating table tilted head up 15 to 20 degrees with left tilt 10 to 15 degrees, a safety strap and padded pressure points.
Reverse Trendelenburg 15 to 20 degrees and left tilt (right side up) 10 to 15 degrees once the ports are in. Secure the patient to the table and protect the pressure areas before tilting, and agree each change of position with the anaesthetist.AI-generated teaching illustration, not an operative photograph.
Image source and reuse
Painted with an AI image tool for the author’s teaching material in October 2026, then checked against the anatomy described on this site. It is simplified for teaching: proportions, colours and tissue planes are not exact, and it is not a photograph of a real operation.

Before tilting, secure the patient, protect pressure areas and agree the change with the anaesthetist.

03Access and ports

Know this
  • Open (Hasson), Veress or optical entry: no clear difference in major injury (Cochrane 2019); a trend to fewer failed entries with open. Use the method you were trained in. Contested
  • Midline scar: avoid blind umbilical entry; use Palmer’s point.
  • Insufflate to 12 to 15 mmHg; 10 to 12 is enough for most, and is used in pregnancy and poor cardiac function.
  • Four ports are standard. The 2020 multi-society consensus prefers multi-port over single-incision because of higher bile duct injury and hernia rates in trials.
  • Inspect the whole abdomen before touching the gallbladder.
Standard four-port placementAI teaching illustration
Front view of the abdomen with four port sites: umbilical 10 to 12 mm (camera), epigastric 10 mm (working), mid-clavicular 5 mm (neck grasper) and lateral 5 mm (fundus grasper), with the patient’s right and left marked.
The American four-port layout: a 10 to 12 mm umbilical camera port, a 10 mm epigastric working port just right of the midline, and two 5 mm ports on the right, mid-clavicular for the neck grasper and lateral for the fundus. This layout is an example for a non-pregnant adult of average build: port sites move with the fundal height in pregnancy, with the liver edge and the thickness of the abdominal wall in obesity, and away from previous scars (special situations). In the French position the surgeon stands between the legs and the working port is on the left.AI-generated teaching illustration, not an operative photograph.
Image source and reuse
Painted with an AI image tool for the author’s teaching material in October 2026, then checked against the anatomy described on this site. It is simplified for teaching: proportions, colours and tissue planes are not exact, and it is not a photograph of a real operation.
Sources

Entry techniques: Ahmad et al., Cochrane 2019. Multi-port over single-incision: Brunt et al., Ann Surg 2020. Guideline

Watch the operative demonstration

Watch Gupta’s official supplementary video on YouTube

Companion video to the 2023 technical article on achieving the critical view of safety, hosted by the Korean Association of Hepato-Biliary-Pancreatic Surgery. The article describes the author’s operative approach; it is a technical demonstration, not a separate guideline.

Opens on YouTube. Age-restricted surgical footage; YouTube may require sign-in. Read the accompanying article.

04The operation step by step

  1. Expose. Take down omental and duodenal adhesions with blunt traction, cold scissors or very brief diathermy on the gallbladder side. Neck adhesions are the inflammatory ones. Decompress a tense gallbladder with a needle through a port; send fluid for culture in cholecystitis.
  2. Retract. Fundus cephalad over the liver towards the right shoulder; Hartmann’s pouch laterally and downward towards the right iliac fossa. This opens the triangle and puts the cystic duct at a right angle to the common duct. Cephalad traction on the infundibulum lines the ducts up: the position of the classic injury.
    3. Retraction changes the duct geometryAI teaching illustration
    Fundus grasper pushing the fundus up and a neck grasper pulling Hartmann’s pouch down and out, opening the triangle so the cystic duct meets the common hepatic duct at a wide angle.
    Correct: fundus up, neck down and out. Inferolateral traction on Hartmann’s pouch opens the hepatocystic angle, so the cystic duct and the common hepatic duct are clearly apart. Retraction improves exposure; it does not establish the Critical View of Safety.AI-generated teaching illustration, not an operative photograph.
    Image source and reuse
    Painted with an AI image tool for the author’s teaching material in October 2026, then checked against the anatomy described on this site and in Gupta and Jain 2019. It is simplified for teaching: proportions, colours and tissue planes are not exact, and it is not a photograph of a real operation.

    Two views of correct two-handed retraction and one of fundal retraction alone. Click any photograph to see it full screen.

    Adequate retraction, first viewPublished figure
    Laparoscopic photograph with two arrows: the fundus is pushed cephalad towards the right shoulder and the neck is pulled down and laterally, opening the hepatocystic triangle.
    Adequate retraction, first view: fundus towards the right shoulder and the neck pulled right inferolaterally (arrows), so the hepatocystic triangle opens and the cystic duct leaves the common duct at an angle.Gupta and Jain 2019, Figure 9 (detail, photograph 1) · CC BY-NC 4.0
    Image source and reuse
    Reproduced from Gupta V, Jain G. Safe laparoscopic cholecystectomy: Adoption of universal culture of safety in cholecystectomy. World J Gastrointest Surg 2019;11(2):62-84, Figure 9 (detail, photograph 1) (doi:10.4240/wjgs.v11.i2.62), under the CC BY-NC 4.0 licence. Cropped from the original figure and resized; no other changes.
    Adequate retraction, second viewPublished figure
    Laparoscopic photograph with two arrows showing the same two-handed retraction from a different angle, with a grasper on the neck pulling it laterally while the fundus is held up over the liver.
    Adequate retraction, second view: the grasper on the neck holds it laterally while the fundus stays cephalad (arrows); the triangle is open and the cystic plate side of the gallbladder is coming into view.Gupta and Jain 2019, Figure 9 (detail, photograph 2) · CC BY-NC 4.0
    Image source and reuse
    Reproduced from Gupta V, Jain G. Safe laparoscopic cholecystectomy: Adoption of universal culture of safety in cholecystectomy. World J Gastrointest Surg 2019;11(2):62-84, Figure 9 (detail, photograph 2) (doi:10.4240/wjgs.v11.i2.62), under the CC BY-NC 4.0 licence. Cropped from the original figure and resized; no other changes.
    Inadequate retractionPublished figure
    Laparoscopic photograph with a single arrow: the fundus alone is pushed cephalad and the gallbladder neck hangs in line with the hepatoduodenal ligament, so the cystic duct and common bile duct are aligned.
    Inadequate retraction: fundal retraction alone (single arrow). The neck is not pulled laterally, the triangle stays closed and the common bile duct lines up with the cystic duct, which is the set-up for misidentification.Gupta and Jain 2019, Figure 9 (detail, photograph 3) · CC BY-NC 4.0
    Image source and reuse
    Reproduced from Gupta V, Jain G. Safe laparoscopic cholecystectomy: Adoption of universal culture of safety in cholecystectomy. World J Gastrointest Surg 2019;11(2):62-84, Figure 9 (detail, photograph 3) (doi:10.4240/wjgs.v11.i2.62), under the CC BY-NC 4.0 licence. Cropped from the original figure and resized; no other changes.
    Retraction of the neckPublished figure
    Two laparoscopic photographs. A: the infundibulum is retracted to the right and downwards and the anterior face of the hepatocystic triangle is exposed, with a green shaded area marking the triangle. B: the infundibulum is retracted towards the umbilical fissure, the gallbladder flips to the left and the posterior face of the triangle is exposed, again shaded green.
    Retraction of the infundibulum (neck). A: pulled right and inferolaterally, it exposes the anterior aspect of the hepatocystic triangle (green). B: pulled towards the umbilical fissure, it exposes the posterior aspect. The two positions give the anterior and posterior views of the Critical View of Safety.Gupta and Jain 2019, Figure 10 · CC BY-NC 4.0
    Image source and reuse
    Reproduced from Gupta V, Jain G. Safe laparoscopic cholecystectomy: Adoption of universal culture of safety in cholecystectomy. World J Gastrointest Surg 2019;11(2):62-84, Figure 10 (doi:10.4240/wjgs.v11.i2.62), under the CC BY-NC 4.0 licence. No changes other than resizing.
    Why retraction mattersPublished figure
    Flowchart with photographs comparing adequate and correct retraction, which opens the hepatocystic triangle both anteriorly and posteriorly and makes the Critical View of Safety likely, with inadequate and incorrect retraction, which fails to open the triangle and makes misidentification likely. Photographs below show the fundus retracted towards the right shoulder with the neck retracted inferolaterally, versus fundal retraction alone, which aligns the common bile duct with the cystic duct.
    Why retraction matters. Fundal retraction towards the right shoulder with inferolateral retraction of the neck opens the hepatocystic triangle; fundal retraction alone lines the common bile duct up with the cystic duct and invites misidentification.Gupta and Jain 2019, Figure 9 · CC BY-NC 4.0
    Image source and reuse
    Reproduced from Gupta V, Jain G. Safe laparoscopic cholecystectomy: Adoption of universal culture of safety in cholecystectomy. World J Gastrointest Surg 2019;11(2):62-84, Figure 9 (doi:10.4240/wjgs.v11.i2.62), under the CC BY-NC 4.0 licence. No changes other than resizing.
    Retracting a thick gallbladderPublished figure
    Two laparoscopic photographs. A: a grasper struggles to hold a thick gallbladder fundus. B: a stay suture through the fundus is held by an instrument to lift it.
    Retracting a thick gallbladder. A: a very thick fundus with a stone impacted in it is hard to grasp and lift. B: a stay suture can help. Avoid perforating the gallbladder if cancer is suspected.Gupta and Jain 2019, Figure 11 · CC BY-NC 4.0
    Image source and reuse
    Reproduced from Gupta V, Jain G. Safe laparoscopic cholecystectomy: Adoption of universal culture of safety in cholecystectomy. World J Gastrointest Surg 2019;11(2):62-84, Figure 11 (doi:10.4240/wjgs.v11.i2.62), under the CC BY-NC 4.0 licence. No changes other than resizing.
  3. Place the landmarks. Rouvière’s sulcus, base of segment IV, duodenum, the duct if visible. Say them out loud. Stay above the sulcus-to-segment-IV line (anatomy).
  4. Open the peritoneum on the gallbladder, posterior leaf first. Start at the neck on the lateral (posterior) side, close to the wall, then the medial side. Opening the back first releases the neck, swings the pouch laterally and exposes the back of the triangle. Keep the incision high on the gallbladder, not on the duct.
    5. Posterior peritoneal divisionPublished photograph
    Posterior/lateral dissection sequence. The neck is retracted medially and the peritoneal fold is divided close to the gallbladder, above the marked R4U line.
    Posterior/lateral dissection sequence. The neck is retracted medially and the peritoneal fold is divided close to the gallbladder, above the marked R4U line.Gupta 2023, Figure 3 · CC BY-NC 4.0
    Image source and reuse
    Gupta 2023, Figure 3. Reproduced under CC BY-NC 4.0. Original image and labels retained; displayed at a responsive size.
    Anterior peritoneal divisionPublished photograph
    Anterior/medial sequence. Inferolateral neck retraction exposes the peritoneal fold; the published broken line marks dissection close to the gallbladder.
    Anterior/medial sequence. Inferolateral neck retraction exposes the peritoneal fold; the published broken line marks dissection close to the gallbladder.Gupta 2023, Figure 4 · CC BY-NC 4.0
    Image source and reuse
    Gupta 2023, Figure 4. Reproduced under CC BY-NC 4.0. Original image and labels retained; displayed at a responsive size.
  5. Clear the hepatocystic triangle. Sweep fat and lymphatics from the triangle towards the gallbladder, from the wall outward. The artery lies just deep to the lymph node; clear it for a short distance and no further. Diathermy sparingly, only on tissue lifted away from the ducts: 2 to 3 mm of spread from a hook can injure the common hepatic duct.
  6. Take the lower gallbladder off the cystic plate. Separate the lower third from the liver bed so the plate is seen behind the neck and the two structures from both sides. The step most often omitted, and the one that proves there is no third structure.
  7. Choose the order. Cystic plate first (separate the lower gallbladder early, alternating sides, then clear the triangle last; Gupta’s preference for leverage and distance from the hilum) or Calot’s triangle first (duct and artery first, plate afterwards). Hybrids are common. The Critical View is not complete until the plate is seen. Expert opinion
    8. Clearing the triangle, cystic plate firstPublished figure
    Six laparoscopic photographs, A to F, of dissection in the hepatocystic triangle. A broken line outlines the exposed cystic plate in panels C and E, and panel F shows the completed critical view with two structures entering the gallbladder.
    Cystic plate first. The plate is exposed by dissecting alternately from the medial (anterior) side (A) and the lateral (posterior) side (B) until enough of it is shown (C and E, broken line). Calot’s triangle is then dissected from the front (D) and the back (E), and the critical view is reached (F).Gupta 2023, Figure 6 · CC BY-NC 4.0
    Image source and reuse
    Reproduced from Gupta V. How to achieve the critical view of safety for safe laparoscopic cholecystectomy: Technical aspects. Ann Hepatobiliary Pancreat Surg 2023;27(2):201-210, Figure 6 (doi:10.14701/ahbps.22-064), under the CC BY-NC 4.0 licence. No changes other than resizing.
    Calot’s triangle firstPublished figure
    Laparoscopic photograph during a Calot's-triangle-first dissection. The cystic duct and cystic artery (arrowheads) have been delineated and a lymph node (N) is visible, but the cystic plate, outlined with a broken yellow line, is still unexposed and labelled "CP (Unexposed)".
    Calot’s triangle first: the cystic duct and cystic artery (arrowheads) have been delineated beside the node (N), but the cystic plate (broken line, “CP unexposed”) has not yet been shown. This is not yet a Critical View of Safety.Gupta 2023, Fig. 7A · CC BY-NC 4.0
    Image source and reuse
    Reproduced from Gupta V. How to achieve the critical view of safety for safe laparoscopic cholecystectomy: Technical aspects. Ann Hepatobiliary Pancreat Surg 2023;27(2):201-210, Fig. 7A (doi:10.14701/ahbps.22-064), under the CC BY-NC 4.0 licence. No changes other than resizing.
    Cystic plate displayedPublished figure
    Laparoscopic photograph later in the same dissection, with the cystic plate now adequately exposed and outlined with a broken yellow line, labelled "CP (Exposed)", and the cystic duct marked by an arrowhead.
    The same dissection once the cystic plate (broken line, “CP exposed”) has been displayed. Only now has the second component of the Critical View of Safety been met.Gupta 2023, Fig. 7C · CC BY-NC 4.0
    Image source and reuse
    Reproduced from Gupta V. How to achieve the critical view of safety for safe laparoscopic cholecystectomy: Technical aspects. Ann Hepatobiliary Pancreat Surg 2023;27(2):201-210, Fig. 7C (doi:10.14701/ahbps.22-064), under the CC BY-NC 4.0 licence. No changes other than resizing.
  8. Confirm the CVS and pause. Three criteria, anterior and posterior views (the doublet view), images recorded. Say “CVS achieved, two structures, clipping the cystic duct” and let anyone challenge it. Cholangiography or ICG now, before clipping (CVS page).
    9. The doublet view in a real operationPublished figure
    Laparoscopic photograph of the Critical View of Safety from the front. The hepatocystic triangle is dissected, the cystic plate is exposed and outlined with a broken line, and only the cystic duct and cystic artery (arrowheads) enter the gallbladder. A yellow double-headed arrow labelled "R4U safety" marks the R4U line, and the dissection lies above it.
    Critical View of Safety, anterior view. The cystic plate is exposed (broken line) and only two tubular structures, the cystic duct and cystic artery (arrowheads), enter the gallbladder. The completed dissection lies above the R4U safety line (yellow arrow). Strasberg score 6 of 6.Gupta 2023, Fig. 8A and Fig. 8B · CC BY-NC 4.0
    Image source and reuse
    Reproduced from Gupta V. How to achieve the critical view of safety for safe laparoscopic cholecystectomy: Technical aspects. Ann Hepatobiliary Pancreat Surg 2023;27(2):201-210, Fig. 8A (doi:10.14701/ahbps.22-064), under the CC BY-NC 4.0 licence. No changes other than resizing.
    Reproduced from Gupta V. How to achieve the critical view of safety for safe laparoscopic cholecystectomy: Technical aspects. Ann Hepatobiliary Pancreat Surg 2023;27(2):201-210, Fig. 8B (doi:10.14701/ahbps.22-064), under the CC BY-NC 4.0 licence. No changes other than resizing.
  9. Clip and divide the cystic artery. Two clips on the stay side, one on the gallbladder side; divide with scissors, not diathermy. Artery before duct where it lies anterior to the duct.
  10. Clip and divide the cystic duct. Clips near the gallbladder, a stump of a few millimetres; do not chase the duct to the junction. Two plus one; jaws fully closed, nothing else caught. Wide (over 6 to 8 mm) or thick duct: loop, suture or stapler, not stacked clips, and ask why it is wide (duct stones, Mirizzi).

    11. Before clipping: confirm all three CVS criteria in the real anterior and posterior views above, then pause with the team. A photograph of applied clips alone does not document the preceding CVS.

  11. Dissect the gallbladder off the liver. Neck up and lateral; hook or spatula in the plane between wall and cystic plate, areolar tissue in view, alternating traction. Going deep bleeds and divides subvesical ducts. Inspect the bed and clips before the last attachment is divided.
  12. Check, wash, extract. Drop the pressure to unmask venous bleeding. Irrigate after spillage and retrieve stones. Bag the gallbladder; enlarge the fascia rather than tear the bag. Record spilled stones and tell the patient (complications).
  13. Drain? Not routinely: more wound infection, no fewer collections (Cochrane 2013). Reasonable after subtotal cholecystectomy, an inflamed bed or a suspected small leak; never a substitute for dealing with a known leak.
  14. Close. Fascia at every port of 10 mm or more, especially the umbilicus, under vision with absorbable suture. Local anaesthetic to the port sites (day case). Absorbable sutures or glue to skin.
More detail and sources

Retraction. Cephalad traction on the infundibulum lines up the cystic and common ducts and is the position in which the classic injury happens; lateral and downward traction on Hartmann’s pouch opens the hepatocystic triangle (Gupta and Jain 2019).

Dissection order. Gupta describes two sequences. In the cystic plate first approach the lower gallbladder is separated from the liver bed early, alternating between the lateral and medial sides until at least the lower third of the plate is exposed, and the triangle is cleared last; the authors prefer it because it gives more leverage on the gallbladder and keeps the dissection away from the hilum. In the Calot’s triangle first approach the duct and artery are delineated first and the plate exposed afterwards (Gupta, Ann Hepatobiliary Pancreat Surg 2023). Expert opinion The preference for the plate-first order is the authors’ practice, not a trial finding.

Doublet view. Sanford and Strasberg (J Am Coll Surg 2014). The intra-operative momentary pause is part of the SAGES programme.

Drains. Routine drainage is not supported after uncomplicated laparoscopic cholecystectomy; reserve a drain for a specific clinical indication (Gurusamy et al., Cochrane 2013). Systematic review

05Energy and clips

Do
  • Short bursts of monopolar coagulation on tissue tented away from what lies behind it.
  • Consider bipolar or ultrasonic devices in a fibrotic bed: less lateral spread, same identification steps.
  • Apply the six clip rule: two structures, three clips each. Reaching for a seventh? Ask what you are clipping. Expert opinion
Don’t
  • Use diathermy inside the triangle before the structures are identified.
  • Use it on or next to the bile duct.
  • Stack clips on a thick or wide duct, or let a clip rest against the common duct: leaks now, strictures later.
Sources

Six clip rule: Deng et al., Art Surg 2021. Expert opinion

06The operation note

Write the note as evidence. “CVS obtained” without a description is worth little when the patient returns jaundiced.

  • Indication and context; findings and difficulty grade.
  • Landmarks seen; how the CVS was obtained and documented; variants.
  • Cholangiography or fluorescence findings.
  • Number and position of clips; spillage; drains; plan.
A template line

“Posterior and anterior peritoneum opened at the neck; hepatocystic triangle cleared of fat; lower third of gallbladder separated from the cystic plate; two structures only seen entering the gallbladder, confirmed in anterior and posterior views (images saved). Pause, confirmed by team. Cystic artery (2 + 1 clips) then cystic duct (2 + 1 clips) divided. No spillage. Fascia closed at umbilicus.”

Source

WSES recommends that the note records the indication and clinical context, the operative findings and difficulty grade, the landmarks seen, whether and how the Critical View of Safety was obtained and documented, any anatomical variants, the findings of cholangiography or fluorescence, the number of clips and their position, any spillage, drains and the plan (de’Angelis et al., WSES 2021). Guideline

07Closing the cystic duct and retrieving the gallbladder

Clips, ligatures or loops

Metal clips are standard. Absorbable clips and absorbable ligatures were no safer and no more dangerous in three small trials; ligating took about 12 minutes longer. A wide or thick duct gets a loop, a suture or a stapler, as above.

Cochrane 2010: 3 trials, 255 patients, evidence too thin to prefer one method

Clip migration

A clip in the common duct years later, acting as a stone nidus, is reported in case series only. It is rare. Keep clips near the gallbladder, and keep the number down. Expert opinion

Retrieval bag

Use a bag when the gallbladder is perforated, infected, thick-walled or suspicious, or when stones have spilled. Many surgeons use one every time. It means a slightly larger fascial opening.

Meta-analysis, 8 studies, 1,805 patients: fewer wound infections and less bile spillage with a bag; no difference in port-site hernia

Spilled stones: retrieve what you can see, wash, record the spillage in the note, and tell the patient. Lost stones cause abscesses months later. See spilled gallstones.

Sources

Gurusamy et al., Cochrane 2010: absorbable versus non-absorbable clips (2 trials, 150) and absorbable ligatures versus clips (1 trial, 105); morbidity no different; all trials at high risk of bias. Systematic review Mohamedahmed, Cureus 2023: four randomised and four non-randomised studies; intra-abdominal collections similar. Mixed trial and observational data

Most recent sources on this page: SAGES Safe Cholecystectomy Program pages (accessed October 2026); Gupta 2023 and Gupta and Jain 2019 (dissection sequence, retraction, and the photographs reproduced under CC BY-NC 4.0); Deng et al. 2021; Cochrane reviews on access (2019) and drains (2013).

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