Single incision laparoscopic surgery approach for obscure small intestine bleeding localized by CT guided percutaneous injection of methylene blue.

INTRODUCTION: Traditionally, localization of small intestine sources of obscure gastrointestinal bleeding has been a challenge. Advances in the field of endoscopy with the introduction of capsule endoscopy and radiographic imaging with computed tomography angiography and visceral angiography have facilitated more accurate visualization of the small intestine. If a bleeding lesion is identified on angiography and surgery is indicated, the use of methylene blue for enteric mapping is very effective to aid intraoperative localization of the culprit. However, when this is not an option, more invasive surgical techniques are required. PRESENTATION OF CASE: We present a new technique used in a patient with angiodysplasia of the small intestine, in where preoperative localization was done using percutaneous computed tomography (CT) guided injection of methylene blue dye. This allowed us to perform a single incision laparoscopic small intestine resection of the culprit.

Introduction

The diagnosis and management of patients with obscure gastrointestinal bleeding (OGIB) traditionally has been very challenging due to the small intestine's length, tortuosity and anatomic location. Overall, lesions in the small intestine account for approximately 5% of cases with OGIB. These subsets of patients are frequently subjected to extensive diagnostic work up, with inherent costly hospital expenses and potential procedure related complications. Moreover, the diagnostic yield is notoriously low. Patients with OGIB typically present with occult blood loss or recurrent episodes of melena or maroon stool without a specific diagnosis. Recent innovations in endoscopic technology have resulted in more effective small intestine imaging such as capsule endoscopy (CE) and deep enteroscopy. The diagnostic yield and therapeutic capabilities of these technologies have been compared with conventional approaches of push endoscopy, intraoperative enteroscopy and radiographic methods.

We report a case of a patient with a jejunal arteriovenous malformation (AVM) identified by computed tomography angiography (CTA) that was successfully marked by preoperative percutaneous computed tomography (CT)-guided injection of methylene blue. This innovative preoperative localization technique was followed by single incision laparoscopic surgery (SILS) with selective segmental jejunum resection.

Case

The patient is an 82-year-old white female who had a two-year history of gastrointestinal bleeding of unknown source. Previous studies included multiple upper and lower gastrointestinal (GI) endoscopies, as well a capsule endoscopy without successful localization of a source of bleeding. She received approximately 104 units of packed red blood cells (PRBCs) over the previous 3 years due to chronic anemia refractory to iron supplements. Her most recent hemoglobin and hematocrit upon presentation were 7.8 g/dl and 25.1%. She was referred after an attempted arteriogram at an outside hospital, performed to localize and embolize the source of bleeding resulted in a partial dissection of the superior mesenteric artery (SMA). A multidisciplinary team decided to perform a computed tomography angiography (CTA) of the abdomen and pelvis to localize the source of bleeding and to assess the SMA dissection. This CTA demonstrated contrast extravasation from the mid jejunum on the left side of the abdomen with evidence of an early draining vein (Fig. 1). The lesion was compatible with an angiodysplasia of the small intestine. Repeating a mesenteric arteriogram was felt to be unsafe; therefore an alternative method of localizing the lesion was necessary.

Fig. 1

Computed tomography angiography showing angiodysplasia of small intestine.

Procedure

After obtaining informed consent and counseling the patient about the planned procedure, a CT arteriogram of the mesenteric arteries was repeated, which confirmed the vascular malformation in the left lower quadrant. A 22-gauge needle was placed percutaneously using CT guidance into a left lower quadrant small intestine loop near the area of the aforementioned malformation. Then methylene blue (0.3 ml) was injected and the needle was removed. This was performed to tattoo the involved loop of small intestine to facilitate intraoperative localization of the lesion.

The patient was then taken directly to the operating room (OR). In the OR, an Olympus Quad port device (Olympus Corp. Tokyo, Japan) was used. This is a SILS access device. Carbon dioxide gas was insufflated in the usual fashion for standard laparoscopy. A laparoscopic exploration was then carried out. Having had prior surgery, the patient's omentum was adherent to the anterior abdominal wall making visualization of the entire abdomen difficult. The omentum was reflected to the right and the methylene blue tattooing was seen. The tattoed loop of intestine was grasped with a laparoscopic intestinal instrument and brought up to the single port device and delivered through the abdominal incision easily (Fig. 2). The small intestinal loop was exteriorized and an enterotomy was performed. A sterile choledochoscope was passed through the enterotomy to confirm the lesion. An area of denuded epithelium with bleeding was identified in close proximity to the tattooing (Fig. 3). A 20-centimeter (cm) segment of this loop of intestine was resected and primarily anastomosed in a standard stapled side-to-side technique. The patient was discharged on post-operative day two.

Fig. 2

Small intestine segment tattooed with methylene blue via CT-guided percutaneous injection.

Fig. 3

Small intestine lumen seen intraoperatively with choledochoscope showing the angiodysplasia with slight bleeding.

The patient was reviewed as outpatient at two and six weeks post-operatively. At the first follow-up visit she described a two-day episode of black stools, but had still been taking oral iron. The iron supplementation was discontinued; and on a follow up visit 4 weeks later, there was no further evidence of bleeding and stool color was normal. Outpatient laboratory work demonstrated hemoglobin and hematocrit of 11.5 g/dl and 37%, respectively. At a routine visit with primary care physician at 20 months since the surgery, the patient denied any signs or symptoms of GI bleeding; and had no procedures or any hospitalization since the surgery.

Discussion

Obscure GI bleeding (OGIB) is defined as bleeding of unknown origin that persists or recurs after an initial negative endoscopic evaluation including colonoscopy and esophagogastroduodenoscopy (EGD). It can be further classified as overt OGIB when there is clinical evidence of visible GI bleeding (e.g. melena or hematochezia) or occult OGIB, when there is no clinical evidence of gross bleeding (e.g., unexplained iron deficiency anemia). Only 5% of GI bleeding occurs between the ligament of Treitz and the ileocecal valve. Approximately 30–40% of OGIB is caused by small intestine angiodysplasia, which is the most common cause in older patients. Angiectasias are ectatic, thin walled, blood vessels with or without endothelial lining. Small arteriovenous communications are often present due to incompetence of the precapillary sphincter. In patients less than 50 years old, the most common sources are tumors such as leiomyomas, carcinoid tumors, lymphomas and adenocarcinoma. Other causes include nonsteroidal anti-inflammatory drug enteropathy, inflammatory bowel disease, Meckel's diverticulum, Dieulafoy's lesions, radiation enteropathy, hemosuccus pancreaticus, small intestine varices and aortoenteric fistula in patients with prior abdominal aortic aneurysm repair.

A thorough history and physical examination is extremely important in the evaluation of a patient with OGIB. There are a number of diagnostics studies available to determine the etiology of OGIB. The diagnostic approach depends upon clinical factors, such as the age of the patient, quality of the prior endoscopic evaluation, and the overt or occult status of the bleeding. The small intestine can be examined using a number of radiologic and endoscopic modalities. Radiologic methods include barium studies, nuclear studies (tagged red blood cell scans and Meckel's scan), computed tomography and magnetic resonance imaging with enteroclysis; and mesenteric arteriography. Endoscopic methods include esophagoduodenoscopy (EGD), colonoscopy, push enteroscopy, double balloon endoscopy (DBE), and capsule endoscopy.

In 2005, Pennazio et al. proposed an algorithm for the diagnosis and management of obscure GI bleeding. In patients presenting with OGIB, upper endoscopy and colonoscopy should be performed. A second look endoscopy evaluation should also be considered before proceeding with capsule endoscopy, since 20–30% of patients undergoing evaluation for obscure bleeding have lesion present in the upper and lower GI tracts that may be missed on initial endoscopic evaluation. Video capsule endoscopy (VCE) should be the next test in the evaluation of patients with GI bleeding, once findings on upper endoscopy and colonoscopy are negative.

Mesenteric angiography is typically reserved to evaluate patients with overt OGIB. Diagnostic yield ranges from 27% to 77% for lower GI bleeding. A randomized controlled trial by Leung et al. demonstrated a superior diagnostic yield of video capsule endoscopy compared with angiography (53.3% vs 20.0%, n − 60). Although VCE enables visualization of the entire small intestine it lacks the potential for therapeutic intervention. Recent advances in angiographic techniques such as superselective embolization (SSMA) are becoming increasingly popular. The data on the clinical utility of angiography and embolization in the specific setting of obscure GI bleeding is very limited.

Once a diagnosis is made, the therapeutic options are nonsurgical and surgical. Of these methods, surgery traditionally offers the best chance of cure. However, the small intestine lacks posterior fixation in the abdominal cavity as oppose to some areas of the colon and also vascular lesions are not readily visible externally upon surgical exploration. For this reason, intraoperative techniques for localization of a source of bleeding are vital to successful surgical management. One half of small intestine bleeding lesions can be missed with older methods described such as visual inspection, palpation, transilumination, enterotomy for direct mucosal inspection and blind resections.

The use of methylene blue dye to aid the localization of these obscure sources of GI hemorrhage has been well described in the literature. The goal is to help the surgeon find the specific small intestine culprit in order to perform a selective bowel resection and preserve small intestine length. Folger et al. reported the first case in 1978, in which 10 ml of methylene blue were injected in the superior mesenteric artery by preoperative angiography. Over the years, numerous case reports using similar techniques have described successful preoperative enteric mapping of the small intestine lesion using methylene blue followed by surgical exploration and selective resection.

Superselective angiographic catheters have enabled Interventional Radiologists to localize more accurately a lesion or bleeding site by cannulating distal visceral vessels. Jiao et al. described a case series of 4 patients with active OGIB, in which preoperatively superselective angiography aid localization of small intestine bleeding site and subsequently the patients were transported to the operating room and 0.5 ml of methylene blue was injected intraoperative, delineating the segment of bowel to be resected. Their success rate was 100%. These methods have the potential risk of catheter dislodgement or malposition during transfer to the operating room. Lundy et al. described another approach by performing the first combined intraoperative SSMA with methylene blue dye enteric mapping followed by immediate small bowel resection. Larger prospective studies are needed to assess the use of superselective mesenteric angiography for embolization and to assist the intraoperative localization of bleeding site in the setting of OGIB.

In the case presented, an iatrogenic SMA dissection limited options for endovascular management. She was not symptomatic from this injury and a multidisciplinary discussion, including a vascular surgeon and an interventional radiologist, recommended against attempting an SSMA. The use percutaneous CT-guided biopsy of small intestine wall lesions have been described in the literature and are found to be safe and accurate. This is considered an option in selected cases with negative endoscopic biopsy. As a result, the CT-guided percutaneous injection with laparoscopic resection was devised.

To the best of our knowledge, this is the first reported description of this technique. One challenging aspect of the technique was the rapid clearance of contrast. A second issue was the peristalsis of the small intestinal loops. The percutaneous needle was placed in the loop of small intestine that looked very similar in appearance and location to the loop seen on CTA. The primary concern was that to ensure that the small intestine to be resected contained the source of obscure bleeding. Prior to segmental resection of the stained segment, a small enterotomy was made and a choledoscope was used to perform an intraoperative enteroscopy, which demonstrated a small mucosal area with signs of recent bleeding. This area was in close proximity to the tattooing area.

Conclusion

Localization of OGIB lesions of the small intestine continues to be a challenge. Of those patients requiring surgical management, current imaging modalities are imperative for successful treatment. We describe another viable option that may be implemented in patients were preoperative imaging indicates a vascular abnormality and are not candidates for endovascular procedures. As demonstrated in our case, CT guided percutaneous techniques may potentially be useful for enteric mapping prior to definitive surgical resection.

Conflict of interest

None declared.

Funding

None.

Ethical approval

Written informed consent was obtained from the patient for publication of this case report and accompanying images. A copy of the written consent is available for review by the Editor-in-Chief of this journal on request.

Author contribution

Case report writing and literature review: Juan Carlos Martinez; Collection of information: Juan Carlos Martinez, John Lukaszczyk; Manuscript submission: Juan Carlos Martinez; Case report editing and review: Jamie Thomas, John Lukaszczyk; Attending interventional radiologist involved in this case: Jamie Thomas; Attending surgeon involved in this case: John Lukaszczyk.