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Файл:Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_605_Библиотеки_им_академика_М_И_Перельмана.pdf
354
Biomedical Engineering in Gastrointestinal Surgery
Figure 9.3 Positioning of the endoscopist at the OR table during hybrid procedures
(A: anesthetist; S
nal surgery: The endoscopist enters the abdomen via the mouth. Accordingly, he
stands at the head of the patient and has to share this position with the anesthetist.
(B) Surgery of the large bowel. Lithotomy position. The endoscopist works from the
opposite side. The adequate placement of the screens is more difficult. Modified by
Dr. A. Schneider.
: surgeon; S2: surgical assistant; E: endoscopist). (A) Upper abdomi-
1
for CLEP is lesions requiring local full-thickness resection of the gastrointestinal wall.
9.1.2 Esophagus
CLEP is mainly focused upon intramural lesions, such as benign leiomyoma, lipoma, and neurinoma. Unlike for other parts of the GI tract, CLEP
is less frequently needed for endoluminal lesions.
9.1.3 Stomach
In the stomach, lesions that are suitable for CLEP are gastric wall tumors,
such as benign gastric stromal tumors (leiomyomas and carcinoids), epithelial growths, such as adenomas, and early gastric cancer
[5]. Bleeding
gastric lesions such as ulcers, Mallory-Weiss tears, and Dieulafoy’s lesions
can be treated by intragastric laparoscopy if peroral endoscopy does not
achieve control of bleeding
[5].
9.1.4 Duodenum
Symptomatic diverticula of the duodenum, duodenal carcinoid tumors,
and adenomas may be indications for CLEP.
355Combined Laparoscopic-Endoscopic Procedures and NOTES
9.1.5 Colon
Indications for CLEP in the colon are similar to those in the stomach—in
particular, adenomas, early cancers with invasion no deeper than the
mucosa and superficial layer of the submucosa (sm1), and benign submucosal lesions
[6].
9.1.6 Contraindications
Lesions of malignant appearance with a high probability of advanced disease should not be considered for local excision by CLEP. Conventional
or laparoscopic surgical resection should be perfor med in these cases.
CLEP is contraindicated in patients who are unfit to undergo anesthe-
sia and in those with clotting disorders.
Endoluminal endoscopy is helpful in multiple regards:
• Exact localization of the lesion.
• Defining the line of resection.
• Selecting the appropriate technique of resection.
• Specimen retrieval.
• Leak tests.
9.1.7 Tumor Localization
Intraoperative flexible endoscopy is the most reliable tool to localize
precisely the site of a lesion.
It would be, of course, more convenient for the surgeon if the tumor
area could be marked prior to the surgery instead of being dependent
upon a demanding intraoperative identification. If the lesion, or better to
say the area which has to be excised, could be clearly marked during preoperative colonoscopy, surgery could be performed without intraoperative
endoscopy. Many attempts were made to indicate the precise location of
the tumor by injecting dye into the gastrointestinal wall. The dye would
be visible at the exterior layer of the wall, enabling the surgeon to confine
his local resection to the pathological finding plus a security margin.
Unfortunately, most dyes, like methylene blue, diffuse in an uncontrolled
way and make it difficult to decide what has to be cut out (
Others tried out marking the lesions with endoscopic (metallic) clips
(
Fig. 9.4B).
Since intraoperative fluoroscopy with the C-arm is w ell established in visceral surgery (see Chapter 5.9.2: Conv entional Radiography (C-Arm)), it is
accordingly easily feasible to perform an intraoperative X-ray to localize the
Fig. 9.4A).
356
Biomedical Engineering in Gastrointestinal Surgery
Figure 9.4 Preoperative mapping of the lesion: (A) Instillation of dyes. The spot of
dye which has been injected priorly into the colonic wall during colonoscopy is
clearly visible from outside. However, it does not represent reliably the internal lesion
since the color diffuses into the tissue and does not mark clear limits. (B) By placing
three or more clips around the lesion, the relevant area can be demarcated.
All from MITI.
Figure 9.5 (A) Intracolonic clips marking the lesion which has to be resected.
(B) Plain abdominal X-ray: The tiny clips are barely visible. Inset: Even under magnification the accurate site of the lesion is difficult to define. All: Courtesy: PD Dr. D.
Wilhelm, Klinikum rechts der Isar.
clip-marked region which has to be resected. In clinical practice, howev er,
this is more difficult than it appears to be. The small clips can be identified,
but it is very hard to perceive the real configuration and the spatial position
of the lesion reliably based on a 2D radiographic image (
Fig. 9.5).
Therefore, preoperative marking is not an option in clinical routine.
Direct visceral exploration and the dialog between surgeons and endoscopists in a combined approach is superior, using diaphanoscopy and
mechanical demonstration.
9.1.8 Defining the Line of Section (Margin)
As soon as it is known where the lesion is located, the extent and the
shape has to be demonstrated to enable the surgeon to excise it precisely.
Combined Laparoscopic-Endoscopic Procedures and NOTES
357
The aim is to cut it out completely. Even if only a few tumor cells are left
the surgery is in vain. On the other hand, as much healthy tissue should
be left as possible. The extent of the area is marked on the exterior gastrointestinal wall either with coagulation spots or by stitches.
9.1.9 Selection of the Appropriate Technique for Tumor Resection
Four different approaches are available. Some lesions which previously
could not be removed during normal endoscopy become suitable for
endoscopic resection in a combined procedure. The laparoscopist helps to
expose the lesion that enables the endoscopist now to place a snare
around or to cut it out with a needle knife. The endoscopist may even
risk a full wall excision, since the hole can be easily closed by a laparoscopic suture. This type of hybrid surgery is called “laparoscopically
assisted endoscopic resection” (LAER) (
Other lesions are situated in an area of the GI tract which makes them
suitable for a tangential (“wedge”) resection using a laparoscopic stapling
device (endoscopically assisted wedge resection: EAWR) (
third group of lesions is only accessible via the transmural route
(
Fig. 9.6C). In these cases, the laparoscopist has to open the intestinal
lumen, supported by the endoscopist who identifies the appropriate place
to enter the lumen. As soon as the lesion is removed, the entry site has to
Fig. 9.6A).
Fig. 9.6B). A
Figure 9.6 Combined endocavitary-endoluminal procedures in the GI tract;
left: gastric procedures; right: colonic procedures. (A) LAER, (B) EAWR, (C) EATR. From MITI.
358 Biomedical Engineering in Gastrointestinal Surgery
be closed again, usually by applying a stapler (endoscopically assisted
transluminal resection: EATR). Whenever possible, LAER or EAWR is
preferred since they are technically less demanding than EATR.
The fourth version of CLEP (not shown in
laparoscopic-endoscopic segment resection. In this case, the whole tubular
segment bearing the lesion is cut out and the two stumps are reconnected
with a normal anastomosis. This type of a CLEP is infrequently used,
since the precision required is less high.
Fig. 9.6) is combined
9.1.10 Specimen Retrieval
Large tumors (more than 1520 mm in diameter) are difficult to retrieve
through a 10-mm trocar. Enlarging the incision for specimen retrieval
can be avoided if the tumor is pulled out by the endoscopist via the natural path (either esophagus/mouth or the rectum).
9.1.11 Leak Test
Before the intervention is terminated, it has to be proven that the suture/
stapling line is absolutely tight. This can be easily done by the endoscopist
by instilling diluted methylene blue into the lumen.
Under surgical conditions, flexible endoscopy is technically more
challenging than in an endoscopy suite, since the proper positioning of
the patient is difficult and gas insufflation should be reduced to a minimum to avoid distension of the GI tract. Maneuvers such as external fixation of the colon are not feasible. Nevertheless, flexible endoscopy is
becoming increasingly popular in visceral surgery. In most ORs of today,
an endoscopy unit including the scopes is part of the regular equipment.
9.1.12 Technical Considerations
Although combined procedures do not require special devices or instrumentation and can be carried out by using the standard laparoscopic and
flexible endoscopic equipment, they are more complex than laparoscopic
or endoscopic stand-alone operations. The crowded situation at the OR
table is additionally deteriorated by the second trolley and the additional
monitors for the complementary view. Dedicated “hybrid ORs” are
helpful with boom-mounted video screens and peripheral devices
(
Fig. 9.7). For endoluminal endoscopy, CO2should be regularly used
since it is faster reabsorbed.
Combined Laparoscopic-Endoscopic Procedures and NOTES
Figure 9.7 Combined laparoscopic-endoscopic intervention: Resection of a spherical
gastric tumor of the gastric fundus visible in the endoscopic image (1). The surgeon
(A) touches the area from outside with his laparoscopic instruments. The endoscopist
(B) observes this manipulation and helps to find the appropriate approach. Both A
and B must have an insight into the corresponding site. A minimum of four screens
is required. The picture-in-picture mode is a way to save the additional two monitors
but is significantly less comfortable
[4]. From MITI.
359
CLEP is gaining importance in the clinical treatment of early oncologi-
cal lesions, but some methodological deficits still have to be eliminated
[7].
A special variant of combined laparoscopic-endoscopic surgeries is the
so-called “safety laparoscopy” during NOTES operation. The NOTES
intervention is monitored by a small (5 mm) laparoscope via the navel
(see
Section 9.2: Natural Orifice Transluminal Endoscopic Surgery -
Surgery without Visible Scars).
9.2 NATURAL ORIFICE TRANSLUMINAL ENDOSCOPIC SURGERY—SURGERY WITHOUT VISIBLE SCARS
It is the vision of all physicians to heal without blood and scars. The use
of natural orifices into the human anatomy is one approach to come
closer to this goal. If the abdominal cavity is entered via an incision
through an internal lumen, the resulting scar is invisible.
The true history of NOTES began in 1901, when Dimitri
Oskarovich Ott of Petrograd, Russia, performed the first endoscopic
360 Biomedical Engineering in Gastrointestinal Surgery
examination of the abdominal cavity through a posterior vaginal incision
using a head mirror and a speculum. He examined the pelvic and abdominal viscera and termed the procedure “ventroscopy.” This approach
remained an exception over decades in visceral surgery, whereas gynecologists started to perform, e.g., hysterectomies through the vagina. In
1998, Hans Seifert in Frankfur t, Germany, introduced the technique of
transgastric drainage of pancreatic necrosis. He was, thus, the first physician in the history of visceral medicine to perform surgical interventions
without laparotomy.
Abdelghani and Mesallum had a paper in Benha Medical Journal
describing “the microaccess approach”—a novel method to access internal
organs via natural body tracts. It was a pilot feasibility study of the transesophageal access into the thorax
[8] but did not gain much attention at
that time.
In 2004, the first published report of peroral endoscopic access to the
peritoneal cavity with liver biopsy in an animal model was described by
Kalloo. NOTES in humans was first carried out by Rao and Reddy in
India in 2005. Using a transoral, transgastric approach, these surgeons successfully carried out an appendectomy. In 2006 in the United States, the
American Society for Gastrointestinal Endoscopy and the Society of
Gastrointestinal Surgeons (SAGES) established a Working Group on
Natural Orifice Translumenal Endoscopic Surgery (NOSCAR). In an
attempt to advance NOTES through cooperation and complementary
approaches, the members of this group published a so-called “White
Paper” to identify goals and tasks in order to make NOTES mature for
clinical purposes
[9]. Since then gastroenterologists and surgeons around
the world have participated in the development of NOTES surgery. In
Germany, the first NOTES surgery was performed in June 2007 by the
team of Zornig in Hamburg. However, up to now (2016) a real breakthrough has not yet been achieved due to the abundant number of
technological problems which were first documented in a SAGES
white paper (
Table 9.1). All of them will be described in this chapter.
The position of NOTES in between internal medicine and surgery is
illustrated in
A general definition of NOTES was coined by T. H. Baron
Fig. 9.8.
[10] in
2007:
NOTES implies surgery endoscopically by initially passing the endoscope
transorally or transanally, then transluminally into areas that would not otherwise
be accessible endoscopically, such as the abdomen and pelvis.
Combined Laparoscopic-Endoscopic Procedures and NOTES
Table 9.1 Potential barriers to clinical practice (according to [9])
Access to peritoneal cavity
Gastric (intestinal) closure
Prevention of infection
Development of suturing device
Development of anastomotic (nonsutur ing) device
Spatial orientation
Development of a multitasking platform to accomplish procedures
Control of intraperitoneal hemorrhage
Management of iatrogenic intraperitoneal complications
Compression syndromes
Training other providers
361
Figure 9.8 A comprehensive therapeutic armamentarium for the interventional treatment of visceral diseases: NOTES requires both perfect endoscopical skills as well as
sound surgical experience. From MITI.
This definition was reasonably extended by the German NOTES asso-
ciation in 2009
[11]:
NOTES may be performed through other natural orifices as well (e.g., vagina,
urethra). Both flexible and rigid instruments may be used.
This addendum was necessary, since it explicitly included the vaginal
approach, which is today the most relevant one.
Prior to the detailed discussion of biomedical engineering (BME)
aspects of NOTES, it has to be pointed out that the term “NOTES”
does not describe one global entity. For example, a NOTES appendectomy via a transgastric access is not the same as a transvaginal NOTES
appendectomy. NOTES solely performed through one GI approach differs from laparoscopically assisted NOTES procedures. Basically, NOTES
362 Biomedical Engineering in Gastrointestinal Surgery
procedures can be subdivided according to numerous criteria. The most
relevant ones are
[12]:
Flexible versus rigid NOTES: NOTES can be performed by means of
rigid (laparoscopic) inst ruments or by flexible endoscopes. Rigid
NOTES (e.g., transvaginal cholecystectomy) is—when possible—easier
to perform than flexible endoscopy with flexible endoscopes (e.g.,
appendectomy).
Hybrid versus “pure” NOTES: The original vision was to perform the
surgery just by one natural opening of the body, but it became soon clear
that transluminal interventions become easier to perform and safer if concomitant laparoscopic surveillance is provided (“safety laparoscopy; see
Section 9.1: Combined Laparoscopic-Endoscopic Procedures (CLEP)).
NO TES determined by the orifice: The type of the orifice selected has a
major influence upon the instrumentation and the surgical technique (see
Section 9.2.1: Access into the Abdominal Cavity). Theoretically, the mouth,
the anus, the vagina, and the urinary tube can be tak en into consideration.
Direct-target versus distant-target organ NOTES: In direct-target NOTES,
the abdomen is entered more or less directly (e.g., via the rectum or the
vagina). If the incision is made into the stomach, a far longer distance
(with increasing navigation problems) has to be overcome.
Independent upon the respective subdivision, there are ongoing challenges for NOTES. To deal with them in detail, it is helpful to consider
the barriers to the clinical introduction of NOTES as defined by the
NOSCAR group
[9].
Most of the 11 “barriers” relate to biomedical engineering, in particular intestinal closure, the development of suturing devices, multitasking
platforms, and anastomotic instruments.
At any rate, to make NOTES mature for clinical purposes is one of
the biggest challenges for BME in clinical medicine.
9.2.1 Access into the Abdominal Cavity
The idea of NOTES is to perform abdominal surgery without any visible
scars. Accordingly, natural orifices shall be used to enter the abdominal
cavity. Four accesses are conceivable (
Unfortunately, an “ideal” access does not exist. Each of them has its
strengths and weaknesses (
Table 9.2).
It is amazing how doctors modified well-established endoscopic techniques to create new, safe NOTES access techniques. The so-called
Fig. 9.9).
Combined Laparoscopic-Endoscopic Procedures and NOTES
Figure 9.9 Four accesses into the abdominal cavity: (A) Transesophageal/transgastrical:
Through the gullet/stomach. (B) Transection through a female pelvis. The accesses from
the left to the right: Transvesical: Through the urinary bladder; Transvaginal: Through
the female genitalia (vagina); Transrectal/transsigmoidal: Through the rectum/sigmoid
colon. All from M. Scholle.
Table 9.2 The main advantages and disadvantages of access
Stomach Colorectum Vagina Urinary bladder
Advantages Low germ load Short distance
to the entry
point, even
large bore
instruments
Disadvantages/
shortcomings
Long distance
between mouth
and stomach;
Difficult closure
of the entry site
Risk of
infection
Simple, safe
access with a
low rate of
complication
In female
patients only
Easy, safe, very
low risk of
contamination
Only for small
bore flexible
instruments
363
“Achilles heel of NOTES” is to create an entrance into the peritoneal
cavity without any har m to the adjacent organs and which can be reliably
occluded afterwards.
9.2.1.1 Transgastric Approach
The stomach is easily accessible with the flexible endoscope, and endoscopists are familiar with the management of wall lesions, bleeds, and even
perforations. Accordingly, the gastric access was selected first in the beginnings of NOTES. If no acid suppressive medication has been administered
before, the low pH value in the stomach prevents germ load.