We use cookies to offer you an optimal experience on our website. By browsing our website, you accept the use of cookies.

Shen-Ann Eugene YEO

Singapore General Hospital
Singapore, Singapore
MBBS, MMed (Surg), FRCS (Ed)
2.6K likes
29.5K views
1 comment
Filter by
Clear filter Specialty
View more

Clear filter Media type
View more
Clear filter Category
View more
Robotic triple docking ultralow anterior resection with intersphincteric resection and coloanal anastomosis
The da Vinci™ surgical robotic system with its increased instrument stability, magnified tridimensional view, and dexterity with 7 degrees of wristed motion of its instruments offers a distinct surgical advantage over traditional laparoscopic instruments. This is especially true in the deep pelvis, where the limited space and visibility make it extremely challenging to perform distal rectal dissection. Additionally, the complete control of the surgeon over the stable surgical platform allows fine and accurate dissection in this area.
For very low rectal tumors close to the anorectal junction, if a sphincter-saving procedure is to be attempted, surgeons will frequently perform an intersphincteric resection (ISR) with a handsewn coloanal anastomosis. If successful, the patient will be able to avoid an abdominoperineal resection and its resulting permanent stoma.
ISR is a technically challenging procedure to perform, especially in male and obese patients. It is because the approach to the intersphincteric plane from the abdominal approach is deep within the pelvis and frequently curves anteriorly, which makes the intersphincteric plane challenging to approach laparoscopically. In addition, ISR from the perineum is also difficult as the anus has a small opening; as a result, when the surgeon sits directly in front of the perineum, assistants will be unable to adequately visualize the operating field, making it very challenging to properly assist for the dissection. It may potentially result in some blind dissection, which may lead to entry into the wrong plane and a poor oncological specimen.
With the da Vinci™ surgical robotic system, this problem can potentially be minimized. First, via the transabdominal approach, the robotic system is able to access deep into the pelvic cavity and dissect down to the intersphincteric plane beyond the puborectalis sling. Secondly, docking the robot and approaching the ISR perineally, the robotic system can also provide a magnified vision, a fine dissection and allow the assistant a good viewing position sitting in front of the perineum to assist in a more productive manner. These advantages of the robotic system will facilitate ISR dissection and retrieval of a superior oncological specimen.
This video features a totally robotic triple docking approach for an ultralow anterior resection with intersphincteric resection and handsewn coloanal anastomosis in a male patient with a low rectal cancer.
SAE Yeo
Surgical intervention
8 months ago
1577 views
5 likes
0 comments
15:36
Robotic triple docking ultralow anterior resection with intersphincteric resection and coloanal anastomosis
The da Vinci™ surgical robotic system with its increased instrument stability, magnified tridimensional view, and dexterity with 7 degrees of wristed motion of its instruments offers a distinct surgical advantage over traditional laparoscopic instruments. This is especially true in the deep pelvis, where the limited space and visibility make it extremely challenging to perform distal rectal dissection. Additionally, the complete control of the surgeon over the stable surgical platform allows fine and accurate dissection in this area.
For very low rectal tumors close to the anorectal junction, if a sphincter-saving procedure is to be attempted, surgeons will frequently perform an intersphincteric resection (ISR) with a handsewn coloanal anastomosis. If successful, the patient will be able to avoid an abdominoperineal resection and its resulting permanent stoma.
ISR is a technically challenging procedure to perform, especially in male and obese patients. It is because the approach to the intersphincteric plane from the abdominal approach is deep within the pelvis and frequently curves anteriorly, which makes the intersphincteric plane challenging to approach laparoscopically. In addition, ISR from the perineum is also difficult as the anus has a small opening; as a result, when the surgeon sits directly in front of the perineum, assistants will be unable to adequately visualize the operating field, making it very challenging to properly assist for the dissection. It may potentially result in some blind dissection, which may lead to entry into the wrong plane and a poor oncological specimen.
With the da Vinci™ surgical robotic system, this problem can potentially be minimized. First, via the transabdominal approach, the robotic system is able to access deep into the pelvic cavity and dissect down to the intersphincteric plane beyond the puborectalis sling. Secondly, docking the robot and approaching the ISR perineally, the robotic system can also provide a magnified vision, a fine dissection and allow the assistant a good viewing position sitting in front of the perineum to assist in a more productive manner. These advantages of the robotic system will facilitate ISR dissection and retrieval of a superior oncological specimen.
This video features a totally robotic triple docking approach for an ultralow anterior resection with intersphincteric resection and handsewn coloanal anastomosis in a male patient with a low rectal cancer.
Robotic abdominoperineal resection (APR) with intraperitoneal puborectalis incision
The da Vinci™ surgical robotic system with its increased instrument stability, tridimensional view, and dexterity with 7 degrees of wristed motion offers a distinct surgical advantage over traditional laparoscopic instruments. This advantage is mainly in the deep pelvis where the limited working space and visibility makes distal rectal dissection extremely challenging. Additionally, the complete control of the surgeon over the stable surgical platform allows fine and accurate dissection in this area.

An abdominoperineal resection (APR) involves the excision of the rectum with a total mesorectal excision (TME), and excision of the anus with an adequate circumferential resection margin (CRM). In a conventional open or laparoscopic approach, the rectal dissection is performed down to the level of the pelvic floor, after which the perineal approach is used to excise the anus and to cut the pelvic floor muscles circumferentially to allow for ‘en bloc’ tumor removal. However, as the pelvic floor is frequently very deep from the skin surface, dissection is technically challenging due to poor visualization, often leading to blind dissection. As a result, many APR specimens suffer from the problem of “waisting” and a positive CRM at the level of the levator ani muscle. In order to solve this problem, some units practice extralevator APR – however, in those cases, the patient ends up with a large perineal defect which frequently needs to be closed with either mesh or flap reconstruction.
With the da Vinci™ robotic system, this problem can potentially be minimized. The robotic system can be used to access deep into the pelvic cavity and make an incision in the puborectalis sling down to the ischiorectal fat. This incision, once completed, allows for easy access from the perineal approach to enter the pelvic cavity and complete the dissection, preventing any blind dissection and facilitating a CRM-clear specimen to be excised.
This video features a totally robotic approach to an abdominoperineal resection for a poorly differentiated anorectal adenocarcinoma, with intraperitoneal incision of the puborectalis sling to facilitate subsequent perineal dissection and specimen extraction.

Clinical case
A 79-year-old female patient presented with a perianal lump and discomfort. Colonoscopy revealed a 2cm mobile adenomatous polypoid lesion at the anorectal junction. Excision biopsy showed a poorly differentiated adenocarcinoma.

CT-scan of the thorax, abdomen and pelvis did not show any distant metastases, and MRI of the rectum did not show any significant locoregional disease. A robotic abdominoperineal resection was performed.

Patient set-up
The da Vinci™ Si™ robotic system was used, and a dual docking approach was chosen.
The patient was placed in a Lloyd-Davies position. Robotic ports (8mm) were placed in the epigastrium, left flank, suprapubic region, and in the right iliac fossa respectively. A 12mm trocar is inserted into the right flank for assistance and stapling.
SAE Yeo
Surgical intervention
11 months ago
445 views
1 like
0 comments
11:27
Robotic abdominoperineal resection (APR) with intraperitoneal puborectalis incision
The da Vinci™ surgical robotic system with its increased instrument stability, tridimensional view, and dexterity with 7 degrees of wristed motion offers a distinct surgical advantage over traditional laparoscopic instruments. This advantage is mainly in the deep pelvis where the limited working space and visibility makes distal rectal dissection extremely challenging. Additionally, the complete control of the surgeon over the stable surgical platform allows fine and accurate dissection in this area.

An abdominoperineal resection (APR) involves the excision of the rectum with a total mesorectal excision (TME), and excision of the anus with an adequate circumferential resection margin (CRM). In a conventional open or laparoscopic approach, the rectal dissection is performed down to the level of the pelvic floor, after which the perineal approach is used to excise the anus and to cut the pelvic floor muscles circumferentially to allow for ‘en bloc’ tumor removal. However, as the pelvic floor is frequently very deep from the skin surface, dissection is technically challenging due to poor visualization, often leading to blind dissection. As a result, many APR specimens suffer from the problem of “waisting” and a positive CRM at the level of the levator ani muscle. In order to solve this problem, some units practice extralevator APR – however, in those cases, the patient ends up with a large perineal defect which frequently needs to be closed with either mesh or flap reconstruction.
With the da Vinci™ robotic system, this problem can potentially be minimized. The robotic system can be used to access deep into the pelvic cavity and make an incision in the puborectalis sling down to the ischiorectal fat. This incision, once completed, allows for easy access from the perineal approach to enter the pelvic cavity and complete the dissection, preventing any blind dissection and facilitating a CRM-clear specimen to be excised.
This video features a totally robotic approach to an abdominoperineal resection for a poorly differentiated anorectal adenocarcinoma, with intraperitoneal incision of the puborectalis sling to facilitate subsequent perineal dissection and specimen extraction.

Clinical case
A 79-year-old female patient presented with a perianal lump and discomfort. Colonoscopy revealed a 2cm mobile adenomatous polypoid lesion at the anorectal junction. Excision biopsy showed a poorly differentiated adenocarcinoma.

CT-scan of the thorax, abdomen and pelvis did not show any distant metastases, and MRI of the rectum did not show any significant locoregional disease. A robotic abdominoperineal resection was performed.

Patient set-up
The da Vinci™ Si™ robotic system was used, and a dual docking approach was chosen.
The patient was placed in a Lloyd-Davies position. Robotic ports (8mm) were placed in the epigastrium, left flank, suprapubic region, and in the right iliac fossa respectively. A 12mm trocar is inserted into the right flank for assistance and stapling.
Laparoscopic complete mesocolic excision (CME) right hemicolectomy with intracorporeal anastomosis
Complete mesocolic excision (CME) in colon cancer surgery has recently gained popularity as increasing evidence points to improved oncological clearance with superior lymph node yield, bigger tumor clearance margins, and higher quality surgical specimens. There are also some indications that it may lead to improved oncological outcomes. The tenets of CME include high vascular ligation at the root of the vessel, dissection along the embryological planes of the colonic mesentery, and adequate margins of bowel from the tumor.
Although the technique was initially described and achieved via a laparotomy, laparoscopic CME was also performed, although it was noted to be technically challenging. The right colon and the variability of vascular anatomy add to the difficulty of the procedure.
Extracorporeal anastomosis is commonly performed for right hemicolectomy in most centers. There are some reported advantages to the intracorporeal anastomosis, namely a potentially higher lymph node yield, a smaller skin incision, and the ability to extract the specimen via a Pfannenstiel’s incision, which has lower rates of incisional hernia.
This video features a laparoscopic CME right hemicolectomy with intracorporeal anastomosis for a malignant polyp.
SAE Yeo
Surgical intervention
1 year ago
11148 views
1078 likes
0 comments
13:33
Laparoscopic complete mesocolic excision (CME) right hemicolectomy with intracorporeal anastomosis
Complete mesocolic excision (CME) in colon cancer surgery has recently gained popularity as increasing evidence points to improved oncological clearance with superior lymph node yield, bigger tumor clearance margins, and higher quality surgical specimens. There are also some indications that it may lead to improved oncological outcomes. The tenets of CME include high vascular ligation at the root of the vessel, dissection along the embryological planes of the colonic mesentery, and adequate margins of bowel from the tumor.
Although the technique was initially described and achieved via a laparotomy, laparoscopic CME was also performed, although it was noted to be technically challenging. The right colon and the variability of vascular anatomy add to the difficulty of the procedure.
Extracorporeal anastomosis is commonly performed for right hemicolectomy in most centers. There are some reported advantages to the intracorporeal anastomosis, namely a potentially higher lymph node yield, a smaller skin incision, and the ability to extract the specimen via a Pfannenstiel’s incision, which has lower rates of incisional hernia.
This video features a laparoscopic CME right hemicolectomy with intracorporeal anastomosis for a malignant polyp.
Laparoscopic right hemicolectomy with complete mesocolic excision for advanced ascending colon cancer
Complete mesocolic excision (CME) with central vascular ligation (CVL) is a potentially superior oncological technique in colon cancer surgery. The tenets of high vascular ligation at the origin and mesocolic dissection facilitate a greater lymph node yield. We present the case of a 70-year-old lady with chronic right iliac fossa discomfort. Computer tomographic scans showed a bulky ascending colon cancer with a 2.6cm right mesocolic lymph node. She underwent laparoscopic CME right hemicolectomy with CVL. Three operative trocars were used (a 12mm trocar in the left iliac fossa, 5mm ports in the left flank and right iliac fossa). Dissection begins in an inferior to superior approach, starting with mobilization of the ileocolic mesentery off the right common iliac vessels, then progressing to separate the mesentery off the duodenum and Gerota's fascia, exposing the head of the pancreas and the duodenal loop. CVL begins with the identification of the superior mesenteric vein (SMV). The vascular structures are isolated individually and ligated high at the level of the SMV, removing the metastatic right mesocolic node ‘en bloc’. Following proximal and distal transections, an intracorporeal ileo-transverse anastomosis is performed. Histology findings demonstrate the presence of a pT4a N2a M0 mucinous adenocarcinoma with 5 out of 17 lymph nodes (including the large mesocolic lymph node) positive for metastasis.
JL Ng, SAE Yeo
Surgical intervention
1 year ago
13199 views
1175 likes
1 comment
05:37
Laparoscopic right hemicolectomy with complete mesocolic excision for advanced ascending colon cancer
Complete mesocolic excision (CME) with central vascular ligation (CVL) is a potentially superior oncological technique in colon cancer surgery. The tenets of high vascular ligation at the origin and mesocolic dissection facilitate a greater lymph node yield. We present the case of a 70-year-old lady with chronic right iliac fossa discomfort. Computer tomographic scans showed a bulky ascending colon cancer with a 2.6cm right mesocolic lymph node. She underwent laparoscopic CME right hemicolectomy with CVL. Three operative trocars were used (a 12mm trocar in the left iliac fossa, 5mm ports in the left flank and right iliac fossa). Dissection begins in an inferior to superior approach, starting with mobilization of the ileocolic mesentery off the right common iliac vessels, then progressing to separate the mesentery off the duodenum and Gerota's fascia, exposing the head of the pancreas and the duodenal loop. CVL begins with the identification of the superior mesenteric vein (SMV). The vascular structures are isolated individually and ligated high at the level of the SMV, removing the metastatic right mesocolic node ‘en bloc’. Following proximal and distal transections, an intracorporeal ileo-transverse anastomosis is performed. Histology findings demonstrate the presence of a pT4a N2a M0 mucinous adenocarcinoma with 5 out of 17 lymph nodes (including the large mesocolic lymph node) positive for metastasis.
Laparoscopic left complete mesocolic excision for stented descending colon cancer
Complete mesocolic excision (CME) with central vessel ligation (CVL) was first introduced with the aim to preserve an intact layer of mesocolon, containing all blood vessels, lymphatic vessels, lymph nodes, and surrounding soft tissue during colorectal cancer resection. The supplying vessels are also transected at their origin for optimal oncological outcomes. This method has been extensively studied in right colonic cancers with improvement in local recurrence and survival rates when compared to the conventional approach. Its excellent results are attributed to the superior lymph node harvest and removal of disseminated cancer cells in the surrounding soft tissue. Similarly, such advantages can be translated to left hemicolectomy with the use of CME with a CVL approach. Additionally, in left hemicolectomy, the vessels ligated (left branch of middle colic and left colic) are branches of vessels from the aorta rather than from the aorta directly, often limiting lymph node harvest. CME with CVL can help to overcome this limitation in left hemicolectomy. We present a video of a laparoscopic CME and CVL in a 48-year-old Chinese male with large bowel obstruction secondary to a descending colonic tumor which was successfully stented one week before.
SAE Yeo, MH Chang
Surgical intervention
1 year ago
3097 views
316 likes
0 comments
08:47
Laparoscopic left complete mesocolic excision for stented descending colon cancer
Complete mesocolic excision (CME) with central vessel ligation (CVL) was first introduced with the aim to preserve an intact layer of mesocolon, containing all blood vessels, lymphatic vessels, lymph nodes, and surrounding soft tissue during colorectal cancer resection. The supplying vessels are also transected at their origin for optimal oncological outcomes. This method has been extensively studied in right colonic cancers with improvement in local recurrence and survival rates when compared to the conventional approach. Its excellent results are attributed to the superior lymph node harvest and removal of disseminated cancer cells in the surrounding soft tissue. Similarly, such advantages can be translated to left hemicolectomy with the use of CME with a CVL approach. Additionally, in left hemicolectomy, the vessels ligated (left branch of middle colic and left colic) are branches of vessels from the aorta rather than from the aorta directly, often limiting lymph node harvest. CME with CVL can help to overcome this limitation in left hemicolectomy. We present a video of a laparoscopic CME and CVL in a 48-year-old Chinese male with large bowel obstruction secondary to a descending colonic tumor which was successfully stented one week before.