THIEME

Precision Surgery in Obstetrics and Gynecology

Nerve-Sparing Radical Hysterectomy: Kobayashi’s Method
Hiroyuki Yoshikawa, MD, PhD1
1 Department of Obstetrics and Gynecology, Ibaraki Prefectural

Central Hospital, Kasama, Ibaraki, Japan
Surg J (NY)

Abstract

Keywords► cervical cancer► nerve-sparing radical
hysterectomy► hypogastric nerve► pelvic splanchnicnerve► pelvic nerve plexus

Address for correspondence Hiroyuki Yoshikawa, MD, PhD,
Department of Obstetrics and Gynecology, Ibaraki Prefectural Central
Hospital, 6528 Koibuchi, Kasama, Ibaraki, Japan 309-1793(e-mail: hyoshi2626@gmail.com).

After Prof. S. Okabayashi introduced Okabayashi Operation in 1921, several surgeons
introduced numerous improvements in Japan. One of them is so-called the Tokyo
Method which was improved and revised by Dr. Kyusaku Ogino (1950), Prof. Takashi
Kobayashi, University of Tokyo (1961, 1970), and Prof. Shoichi Sakamoto, University ofTokyo (1981). The nerve-sparing radical hysterectomy without sacriﬁcing radicality was
introduced in 19611 and improved in 1970 by Prof. Kobayashi.2 The autonomic nerve
pathway including hypogastric nerve (sympathetic nerve), pelvic splanchnic nerve(parasympathetic nerve), and pelvic nerve plexus as a junction of the two nerves andthe branch of the plexus to the bladder (vesical nerve branch) are preserved except inadvanced cases. He divided the process of nerve-sparing surgery into four steps forseparating the autonomic nerve pathway from adjacent tissues along the pathway
consisting of cardinal, sacrouterine, rectouterine/vaginal, and vesicouterine ligaments.
The ﬁrst step is separation of the cardinal ligament (deep uterine vessels) from thepelvic splanchnic nerve. The second step is separation of the medial side of severed
cardinal ligament from the pelvic nerve plexus. The ﬁrst and second steps are
performed in the lateral side of the autonomic nerve system. The third step isseparation of sacrouterine and rectouterine/vaginal ligaments from hypogastric nerve
and pelvic nerve plexus. The third step is necessary for achieving high radicality,
namely, for severing the sacrouterine and rectouterine/vaginal ligaments near the
rectum without damage to the pelvic nerve plexus. The fourth step is separation ofparavaginal tissues and posterior (deep) layer of the vesicouterine ligament from thevesical nerve branches of the plexus. The third and fourth steps are performed in the
medial side of the autonomic nerve system.

Preoperative Evaluation and Imaging

Surgical Steps

Patients should not be older than 72 years of age and thelesion should be, by the International Federation of Gynecology and Obstetrics classiﬁcation, Stage IB1, Stage IB2, Stage
IIA1, or Stage IIA2.

1. Incision of abdominal wall.
2. Preliminary openin,g of paravesical and pararectal
spaces.
3. Pelvic lymphadenectomy.

DOI https://doi.org/
10.1055/s-0041-1728751.
ISSN 2378-5128.

© 2021. The Author(s).
This is an open access article published by Thieme under the terms of theCreative Commons Attribution-NonDerivative-NonCommercial-License,
permitting copying and reproduction so long as the original work is given
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Yoshikawa

4. Dissection of the cardinal ligament.
5. Dissection of the sacrouterine and rectovaginalligaments.
6. Dissection of vesicouterine ligament.
7. Cutting of vagina and paracolpium.
8. Closure of abdominal wall.

In-Depth Explanation
Positioning of the TeamThe surgeon, if right-handed, begins the operation standingon the right side of the patient and maintains this position
until the left cardinal ligament is severed. He then shifts tothe left side of the patients and continues the operation until
its completion.

Special Instruments
The following instruments have been specially designed forthe operation. Self-retaining retractor with a third rubber
blade, rectum retractor, bladder retractor, right angled
retractor, ureter hook, horizontally curved forceps, andmembrane forceps.
1. Incision of abdominal wall and pelvic peritoneum
The abdomen is opened through a midline incisionextending from the mons veneris to above the umbilicus.
The specially designed self-retaining retractor is particularly
useful in major gynecological operation such as radical
hysterectomy.
Kocher’s forceps with long, straight jaws are applied to theround ligament and the fallopian tube, on each side, close to
the uterus to hold it and to prevent the spreading of cancer
cells. It is advisable to cut the round ligament before theinfundibulopelvic ligaments as it enables a better direct viewof the ureter and its direction.
After the peritoneum of the vesicouterine pouch isincised, the anterior peritoneal ﬂap is sutured to the abdominal wall with one stitch. The bladder is then separated fromthe cervix as a preliminary to exclude bladder involvementwith tumor and so ensure operability.
2. Opening of paravesical and pararectal spaces
The paravesical space and pararectal space are opened sothat the anatomical relationship between organs in thepelvic cavity can be better determined. The pararectal spacecan be opened easily by separating the ureter from the pelvic
vessels in a medial direction. The space is cleared until theposterior side of the cardinal ligament is seen.
3. Pelvic lymphadenectomyFirst, the external iliac vessels are isolated from the psoas
muscle and then the pelvic wall is exposed to sufﬁcient depth
as to reveal the obturator nerve. Continuing this procedure theentire lengths of both the external iliac artery and vein are laidbare and all the branches of the hypogastric veins are exposed.
Next, the lymph nodes are dissected distally along thepelvic wall in the order shown. A recommended techniquefor removal of nodes is to dissect the perivascular sheet fromthe vessels, lifting the nodes with the sheet by membrane
The Surgery Journal© 2021. The Author(s).

forceps, and pressing down the vessels at the same time bymeans of a swab or scissors. The pelvic lymph vessels
converge to a main trunk at the common iliac vessels.
The order of dissection is common iliac nodes followed byexternal iliac nodes. The lymph nodes are isolated together
with the perivascular sheet. The upper end of the common
iliac node is picked up and the main lymph trunk is thenclamped. The common iliac lymph nodes should be removed
carefully on their deep aspect, protecting the venous wall.
Now the order becomes lateral suprainguinal nodes followed by medial suprainguinal nodes. After dissecting theexternal iliac nodes, the retractor is raised to permit removalof the suprainguinal nodes. First, the lateral part of thesenodes is removed, then the medial part. Care should be taken
not to damage the inferior epigastric vein at this time. The
medial suprainguinal nodes are removed to a point where
the periosteum is exposed. Extreme care should be taken not
to damage the innominate vein communication between theexternal iliac vein and the obturator vein.
Next, the obturator nodes are dissected followed by theinternal iliac nodes. Since the lateral part of the node mass has
already been completely isolated from the pelvic wall, thenodes can be removed from the surface of the cardinal ligament. The nodes can be removed easily only in this way. Whenremoving the obturator nodes, the obliterated umbilical arteryis exposed. This facilitates the following part of the operation. If
the sacral nodes are enlarged, they are also cleared.
The obliterated umbilical artery is lifted up and theuterine artery is isolated. Double ligatures are then applied
and the artery is severed between ligatures. About 5 cm ofthread are left on the side of the uterus as a marker.
The ureter is isolated from the posterior leaf of the broad
ligament. The ureter enters the tunnel which is formed between
the anterior and posterior layers of the vesicouterine ligament.

• Tips and Warnings
To dissect pelvic lymph nodes completely, it is importantto remove the internal iliac (hypogastric) nodes aroundthe superior gluteal vein and the obturator nodes on thepsoas muscle.

4. Dissection of cardinal ligament (►Figs. 1, 2 and 9)
In the left side, the paravesical space is opened. Insert theright-angled retractor and the rectum retractor into the inletof the paravesical space to keep the area opened widely. The
pararectal space along the surface of the sacral bone is
opened by pushing the rectum medially inside the pelvic
nerve ﬁbers. The cardinal ligament is now isolated.
The lymph nodes situated on the anterior and posterior
surfaces of the cardinal ligament are next dissected. Removal of
the lymph nodes at the base of the cardinal ligament isimportant as a lymph node metastasis frequently occurs here.
At this stage the blood vessels in the cardinal ligament aredealt with. If there is a blood vessel running independently, itKobayashi’s Nerve-Sparing Method

Fig. 1 (Reproduced with permission from Yoshikawa H. In: Konishi I,
Hiramatsu Y, Sakuragi N, Takeda S, eds. OGS NOW, No.5. (Japanese).
Tokyo: Medical View; 2011:46–55. Copyright © Medical View).

is safer to ligate and sever it separately. Forceps are inserted
between the two parts of the cardinal ligament. The upper
soft part is the vascular part, and the lower hard bundle
contains the autonomic nerve.
Two Kocher’s forceps are applied to the vascular part, one
outside and the other inside the ureter. The cardinal ligamentis cut between the forceps. The stump on the lateral side isligated with thread. Operation on the left side is now
complete.

YoshikawaIn similar fashion the surgeon starts by opening theparavesical and pararectal spaces and then proceeds tolymphadenectomy, ligature of right uterine artery, exposureof the right ureter, and dissection of the right cardinal
ligament.
5. Dissection of the sacrouterine and rectovaginal ligaments (►Fig. 1)
The peritoneum of the Douglas pouch and the posteriorleaves of the broad ligament are transversely incised. The
vaginal wall is separated from the rectum to a point below
the cardinal ligament to permit extirpation of an ample
vaginal cuff. To accelerate resumption of normal bladderfunction after operation it is advisable to preserve thebranches of the pelvic nerves supplying the bladder.
Prior to severing the sacrouterine and rectovaginal ligaments, complete mobilization of the vascular part of the
cardinal ligament from the nerve tissues should be made.
A sheet of sympathetic nerve ﬁbers is ﬁrst separated fromthe lateral surface of the sacrouterine ligament with scissors
and can be severed without risk of bleeding. Sheets of tissue
containing sympathetic nerve ﬁbers are easily recognized asthey run along the rectum.
The branches of the pelvic nerve plexus supplying theuterus are divided, extreme care being taken not to sever
the vesical branches. By pushing up the caudal end of thesympathetic nerve plate, the pelvic nerve plexus is usuallypreserved automatically and no special manipulation isneeded.
Two curved forceps are applied to the rectovaginal ligament which is then cut between the forceps and ligated.
Sometimes repetition of the procedure is necessary to get as
deep a separation as possible. The same procedure is madeon the other side.

• Tips and Warnings
The most important idea in Kobayashi’s method is thatthe cutting line of the nerve system is different from thatof the sacrouterine and rectovaginal ligaments. Separation of the nerve system from the sacrouterine andrectovaginal ligaments (third step) is mandatory before
severing these ligaments and the nerve system.

Fig. 2 Second step: Separation of cardinal ligament from pelvic
splanchnic nerve and pelvic nerve plexus 2. The second step isseparation of the medial side of the severed cardinal ligament fromthe pelvic splanchnic nerve and pelvic nerve plexus. (Reproduced withpermission from Yoshikawa H. In: Konishi I, Hiramatsu Y, Sakuragi N,
Takeda S, eds. OGS NOW, No.5. (Japanese). Tokyo: Medical View;
2011:46–55. Copyright © Medical View.)

6. Dissection of vesicouterine ligament (►Fig. 1)
The bladder must be separated adequately from theanterior wall of the vagina to the same extent that therectum is separated from its posterior wall.
First, the ureter is separated from the uterine artery andits entry into both layers (anterior and posterior layers) of thevesicouterine ligament (the so-called tunnel). The ureter isdisplaced to the lateral side. Curved Pean forceps are inserted
into the tunnel. In passing Pean forceps through the tunnel,
their tip must be directed medially or they may injure thejuxtavesical portion of the ureter. Two horizontally curved
forceps are then applied. The part between the forceps in the
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Kobayashi’s Nerve-Sparing Method

Yoshikawa

anterior layer is cut and ligated. To prevent the kinking of theureter, it is highly advisable to carry out this procedure in
two or three steps.
The ureter is isolated from the surface of the posterior part. It
is pushed laterally, widely exposing the posterior layer. With
the bladder pressed downward, a triangular-shaped recesssurrounded by the bladder, the paracolpium, and the caudal
margin of the posterior layer is seen. Curved Pean forceps arenext inserted into the recess below the posterior layer of theligament. After opening the blades of the inserted forceps, twohorizontally curved forceps are allied onto the ligament at thepart between the opened blades. The part between the forceps
in the posterior layer is cut and ligated. At this time, the ureter
should be carefully separated laterally so that the forceps can beapplied approximately 5 mm from the ureter to avoid damage.
Next, posterior part of the vesicouterine ligament is severed andthe ureter is completely separated from the vagina and uterus.

• Tips and Warnings
The cranial or upper part of vesical branches exists along
the outside of the posterior layer of the vesicouterine
ligaments. The fourth step is separation of paracolpium
from vesical branches of the pelvic nerve plexus.

7. Cutting of vagina and paracolpium
The bladder is further separated from the vaginal wall andparacolpium (paravaginal tissues) to a required level. The
paracolpium of both sides should be cut and ligated as deeply
as possible at the level required to protect against vaginal
stump recurrence. Utmost care should be taken not to cut
any remaining autonomic nerve ﬁbers. The anterior wall of
the vagina is cut. The cut end of the vagina is now clampedwith Kocher’s forceps, and the posterior wall of vagina is
incised. Thus, the uterus is completely extirpated. This isfollowed by closure of the vaginal canal.

Fig. 3 Autonomic nerve pathway. Figure shows Kobayashi’s originalﬁgure demonstrating pelvic autonomic nerve pathway in his textbook
published in 1970. The autonomic nerve pathway including hypogastric nerve (sympathetic nerve), pelvic splanchnic nerve (parasympathetic nerve), and pelvic nerve plexus as a junction of the twonerves and the branches of the plexus to the uterus and bladder(uterine branch and vesical branches). (Reproduced with permission
from Yoshikawa H. In: Konishi I, Hiramatsu Y, Sakuragi N, Takeda S,
eds. OGS NOW, No.5. (Japanese). Tokyo: Medical View; 2011:46–55.
Copyright © Medical View.)

the two nerves and the branches of the plexus to the bladder(vesical nerve branches) are preserved except in advanced
cases (►Figs. 3–7). The process of nerve-sparing surgery is
divided into four steps for separating the autonomic nerve
pathway from the adjacent tissues along the pathway• Tips and Warnings
To remove 3 cm long of upper vagina and paravaginal
tissues, 3 cm wide of the paravaginal tissues in each sideshould be cut and ligated.

8. Closure of abdominal wall
Two J-VAC tube drains are inserted into the dead space oneach side of the pelvis and brought through the abdominal
wall. The abdominal wall is closed to complete the operation.

Nerve-Sparing Methods
The autonomic nerve pathway including the hypogastricnerve (sympathetic nerve), pelvic splanchnic nerve (parasympathetic nerve), and pelvic nerve plexus as a junction of
The Surgery Journal© 2021. The Author(s).

Fig. 4 Autonomic nerve pathway. (Reproduced with permission from
Yoshikawa H. In: Konishi I, Hiramatsu Y, Sakuragi N, Takeda S, eds.
OGS NOW, No.5. (Japanese). Tokyo: Medical View; 2011:46–55.
Copyright © Medical View.)

Kobayashi’s Nerve-Sparing Method

Yoshikawa

consisting of cardinal, sacrouterine, rectouterine/rectovaginal, and vesicouterine ligaments.

Fig. 5 Third and fourth steps: Separation of sacrouterine andrectovaginal ligaments, and paracolpium from hypogastric nerve,
pelvic nerve plexus, and vesical branches. The third step is separationof sacrouterine and vaginal ligaments from hypogastric nerve andpelvic nerve plexus. The third step is necessary for achieving highradicality for severing the sacrouterine and rectovaginal ligaments
near the rectum without damage to the pelvic nerve pathway. The
fourth step is separation of paracolpium from vesical branches of thepelvic nerve plexus. The cranial part of vesical branches exists along
the outside of the posterior layer of the vesicouterine ligaments.
(Reproduced with permission from Yoshikawa H. In: Konishi I, Hiramatsu Y, Sakuragi N, Takeda S, eds. OGS NOW, No.5. (Japanese).
Tokyo: Medical View; 2011:46–55. Copyright © Medical View.)

First step: Separation of the cardinal ligament (deeputerine vessels) from the pelvic splanchnic nerve(►Figs. 8 and 9).
Second step: Separation of the medial side of the severed
cardinal ligament from the pelvic splanchnic nerve andthe pelvic nerve plexus (►Figs. 2, 8, and 10). The ﬁrst
and second steps are performed in the lateral side of theautonomic nerve system.
Third step: Separation of sacrouterine and rectouterine/
rectovaginal ligaments from hypogastric nerve and pelvic
nerve plexus (►Figs. 5, 8, and 10). The third step isnecessary for achieving high radicality, namely, for severing the sacrouterine and rectouterine/rectovaginalligaments near the rectum without damage to pelvic
nerve plexus.
Fourth step: Separation of paravaginal tissues (paracolpium) and posterior (deep) layer of the vesicouterine
ligament from the vesical nerve branches of the plexus(►Figs. 5, 8, and 10). The third and fourth steps are
performed in the medial side of the autonomic nerve
system.
In ►Figs. 6 and 7, the blue boxes indicate the connective
tissues consisting of sacrouterine and rectovaginal ligaments
and paracolpium. The yellow boxes indicate autonomic nerve
pathway including hypogastric nerve, pelvic splanchnic
nerve, pelvic nerve plexus, uterine branch, and vesicalbranches.
The red lines show the cutting lines of the connective
tissues and the nerve system in original Okabayashi operation (►Fig. 6). The cutting line of the nerve system is in

Fig. 6 Original Okabayashi operation. In the ﬁgure, the blue boxes indicate the connective tissues consisting of sacrouterine and rectovaginalligaments and paracolpium. The yellow boxes indicate autonomic nerve pathway including hypogastric nerve, pelvic splanchnic nerve, pelvic
nerve plexus, uterine branch, and vesical branches. The red lines show the cutting lines of the connective tissues and the nerve system in original
Okabayashi operation. The cutting line of the nerve system is in common with that of the sacrouterine and rectovaginal ligaments. (Reproducedwith permission from Yoshikawa H. In: Konishi I, Hiramatsu Y, Sakuragi N, Takeda S, eds. OGS NOW, No.5. (Japanese). Tokyo: Medical View;
2011:46–55. Copyright © Medical View.)
The Surgery Journal© 2021. The Author(s).

Kobayashi’s Nerve-Sparing Method

Yoshikawa

Fig. 7 Kobayashi’s nerve-sparing method. The cutting line of the nerve system is completely different from that of the connective tissues in
Kobayashi’s nerve-sparing method. The most important idea in this method is that the cutting line of the connective tissues is conserved incomparison with original Okabayashi operation without damage to the pelvic nerve pathway. Separation of the nerve system from thesacrouterine and rectovaginal ligaments is mandatory for the purpose of this method. (Reproduced with permission from Yoshikawa H. In:
Konishi I, Hiramatsu Y, Sakuragi N, Takeda S, eds. OGS NOW, No.5. (Japanese). Tokyo: Medical View; 2011:46–55. Copyright © Medical View.)

Fig. 9 First step: Separation of cardinal ligament from pelvic
splanchnic nerve 2. The ﬁrst step is separation of the cardinal ligament
from the pelvic splanchnic nerve. (Reproduced with permission from
Yoshikawa H. In: Konishi I, Hiramatsu Y, Sakuragi N, Takeda S, eds.
OGS NOW, No.5. (Japanese). Tokyo: Medical View; 2011:46–55.
Copyright © Medical View.)

Fig. 8 Autonomic nerve pathway before separation from the adjacent ligaments. This ﬁgure shows autonomic nerve pathway before
separation from the adjacent ligaments. (Reproduced with permission
from Yoshikawa H. In: Konishi I, Hiramatsu Y, Sakuragi N, Takeda S,
eds. OGS NOW, No.5. (Japanese). Tokyo: Medical View; 2011:46–55.
Copyright © Medical View.)

The Surgery Journal© 2021. The Author(s).

Kobayashi’s Nerve-Sparing Method

Yoshikawacommon with that of the sacrouterine and rectovaginalligaments.
The red lines show the cutting lines of the connective
tissues, red boxes, and the nerve system, yellow boxes, in
Kobayashi’s nerve-sparing method (►Fig. 7). The most important idea in this method is that the cutting line of thenerve system is different from that of the sacrouterine andrectovaginal ligaments. The cutting line of the connective
tissues in this method is almost the same with that in
Okabayashi operation. Separation of the nerve systemfrom the sacrouterine and rectovaginal ligaments is mandatory before severing these ligaments and the nerve system.
Conﬂict of Interest
None declared.

References
1 Kobayashi T. Abdominal radical hysterectomy with pelvic

lymphadenectomy for cancer of the cervix. Tokyo: Nankodo
1961:1–499 (in Japanese)
2 Kobayashi T. Treatment of cervical cancer IV-V. Modern Textbookof Obstetrics and Gynecology 8E- Cervical Cancer. Tokyo:
Nakayama Shoten 1970:325–352 (in Japanese)
3 Sakamoto S, Takizawa K. An improved radical hysterectomy withfewer urological complications and with no loss of therapeutic
results for invasive cervical cancer. Baillieres Clin Obstet Gynaecol
1988;2(04):953–962

Fig. 10 Autonomic nerve pathway after separation from adjacentligaments. This ﬁgure shows autonomic nerve pathway after separation from the adjacent ligaments. (Reproduced with permission
from Yoshikawa H. In: Konishi I, Hiramatsu Y, Sakuragi N, Takeda S,
eds. OGS NOW, No.5. (Japanese). Tokyo: Medical View; 2011:46–55.
Copyright © Medical View.)

The Surgery Journal© 2021. The Author(s).