By Ha, Chi D Alvear, Domingo T; Leber, David C
We evaluated the use of duodenal derotation as a surgical option for superior mesenteric artery syndrome (SMAS) in two groups of young patients. Sixteen patients with SMAS diagnosed by barium upper gastrointestinal series (UGI) from 1974 to 2001, and six patients diagnosed by computerized tomography with three-dimensional reconstructions (3D CT) from 2001 to 2007 were referred to our surgical service, 19 of whom underwent duodenal derotation as the primary surgical treatment after a failed trial of conservative treatment. The main measured outcomes were the resolution of typical symptoms of SMAS and the development of long-term surgical complications. Of the first 16 patients, three (19%) responded to nasojejunal feedings. Of 13 patients undergoing derotation, only one (7.7%) failed derotation and required a gastrojejunostomy bypass, whereas 12 (92%) became asymptomatic after the derotation procedure. After a mean follow-up of 5.13 years (range 0.1-15), two patients (15%) presented with small bowel obstructions and were treated with a simple lysis of the adhesion. All six patients from 2001 to 2007 responded well to surgical derotation. Overall, duodenal derotations successfully relieved symptoms in 18 out of 19 (95%) patients with SMAS, with two (11%) major long-term surgical complications. No volvulus was observed in our patients at the mean follow-up of 4.37 years. SUPERIOR MESENTERIC ARTERY syndrome (SMAS) was first fully described by Rokitansky in 1861.1 Based on the autopsies on a group of young asthenic females with postprandial abdominal discomfort and intermittent emesis of copious amounts of bilious fluid, Rokitansky attributed the cause of the symptoms to the compression of the duodenum between the aorta and the superior mesenteric artery (SMA).1 The study stimulated a small series of case reports until 1927 when Wilkie published the largest case series of 75 patients diagnosed witii SMAS based on clinical presentations and barium upper gastrointestinal series (UGI).2 However, from 1927 to the 1960s, many authors showed skepticism about this disease entity because there was no clearly defined diagnostic standard. The interest in the disease was resurrected when hypotonic duodenography and angiography allowed the measurements of the aortomesenteric angle and distance in the 1960s.3 Since the 1980s, SMAS has been widely accepted as a true disease entity due to the capability of computerized tomography to measure the aortomesenteric angle and distance with ease; and witii computerized tomography with three- dimensional reconstructions (3D CT), the duodenal compression could be evaluated in reference to the surrounding organs (Fig. IA-C).4
The prevalence of the disease is generally unknown. Some authors report a prevalence of 0.13-0.3 per cent based on barium UGI,5, 6 and an incidence of 0.5 per cent in patients with surgery for scoliosis or spinal cord injury.7, 8 These studies however have always been criticized for the lack of clear diagnostic criteria. Most authors would agree that approximately twothirds of the patients are female,2 75 per cent within the age range of 10 to 39 years,9 and up to 80 per cent with an asthenic body habitus.10
The symptomatology of this disease has been well characterized, especially by Wilkie.2 Patients usually experience epigastric fullness and nausea shortly after food ingestion, then epigastric pain approximately 30 minutes after meals. Emesis is uncommon, and when present, is bilious and episodic. The symptoms can be severe enough to lead to early satiety, food-fear, and weight loss, which consequently enhance the anatomic compression due to the reduction in the fat pad at the mesenteric root. Most patients find some relief with postural (Goldthwaite) manipulations after meals by assuming a recumbent, left or right lateral decubitus, and/or knee- to-chest positions. The patients usually describe a period of intense flatulence 30 minutes after assuming the positions, followed by the relief of the symptoms.
FIG. 1. 3D CT of a patient with SMAS. The stomach and proximal duodenum are severely distended on the coronal view (A). The third portion of the duodenum (arrows) is compressed at the aortomesenteric angle on cross-sectional (B) and sagittal (C) views. The aortomesenteric angle and distance are approximately 16[degrees] and 6 mm, respectively, in this case.
The classic treatment option for SMAS has been duodenojejunostomy, first proposed by Bloodgood in 1907,11 and first performed by Stavely in 1908,12 which has up to a 90 per cent success rate in terms of symptomatic relief in patients undergoing the procedure.13 The most important advantage of this approach is the ease of performing the procedure. As a general intraoperative finding, the duodenum is redundant, dilated, and allows an easy anastomosis with a segment of the jejunum. However, major disadvantages of this approach are the possibilities of bleeding, leakage, and stricture of the anastomotic site. There is also the creation of a nonphysiologic bilious circulation loop, the significance of which is unknown.
We have advocated an anastomosis-free procedure that preserves the intact flow of the existing intestinal tract.14 This involves the derotation of the intestinal tract in such a way that the duodenum is on the right of the aortomesenteric angle (AMA) and the colon is on the left. The end result is the third portion of the duodenum being rotated out of the AMA. This article summarizes our experience with this technique since 1974.
Methods
The data was collected in two separate periods to make two distinct study groups. In the first period from 1974 to 2001, the patients’ records were reviewed retrospectively, and the information on gender, age, symptoms, treatment, and response to treatment was collected. The diagnosis in this period was based on clinical presentations and UGI. In the second period from 2001 to 2007, patients were diagnosed by clinical presentations and 3D CT, and were evaluated prospectively as a cohort. The data on gender, body mass index, symptoms, signs, other studies before 3D CT, length of hospital stay, days required to be asymptomatic, and long-term follow-up were collected.
Before consideration for SMAS, all patients had at least a 6- week history of persistent postprandial abdominal discomfort, nausea, with or without emesis, and weight loss. During this period, other common causes were usually ruled out by the referring physicians with complete radiologic, endoscopic, and psychologic evaluations, most of which were nondiagnostic. If other common causes were not found, workup for SMAS was initiated. For our patients within the first period from 1974 to 2001, a confirmation study with a UGI showed all of the following features: dilated first and second duodenal portions, an abrupt vertical compression of the third duodenal portion, antiperistaltic flows (“to-and-fro” peristalsis) proximal to the vertical obstruction, and a delay of transit into the jejunum of at least 4 hours. Since 2001, when 64- slice 3D CT became readily available in our service area, the confirmation study was switched from UGI to 3D CT. An aortomesenteric distance of 8 mm and an aortomesenteric angle of 20[degrees] were used as the critical measurements for our study. These were obtained using a maximum intensity projection protocol on the three-dimensional reconstructions (Fig. 1C).4
Upon diagnosis of SMAS, all patients underwent at least 6 weeks of conservative treatment. Older children, who could follow instructions, were directed to have multiple small frequent meals (6- 8 meals/day), in addition to a peristalsis-stimulating agent such as metoclopramide. All were given instructions on postural (Goldthwaite) treatment consisting of the following: assuming a recumbent position, raising the pelvis, kneeling, and lowering the shoulders to allow the flatulence to pass. Nasojejunal feeding tubes were offered to these patients, but they were generally refused. In younger children, who had difficulty following instructions or those with a severe malnutritional status, a nasojejunal feeding was initiated for at least 6 weeks.
Before a derotation procedure, intraoperative confirmation was obtained by examination of the duodenum to ensure that the diameters of the first and second portions were at least 50 per cent larger than that of the fourth portion and the proximal jejunum, and that an abrupt compression of the third portion within the aortomesenteric angle was appreciated. We also evaluated the duodenum for its usual location to rule out malrotation. We believe these intraoperative findings are highly specific for SMAS.
All of our laparotomies for SMAS were performed through a transverse right upper quadrant incision. We first incised the retroperitoneal reflection within the right gutter and mobilized the right colon and terminal ileum as well as their mesenteries from the retroperitoneal attachment (Fig. 2A-B). The goal was to expose the third part of the duodenum as well as to shift the right colon weight completely to the left side of the aortomesenteric angle. We always performed an incidental inversion appendectomy. At this point, the inferior aspect of the third part of the duodenum was usually well identified, usually being dilated and compressed by the aortomesenteric angle. We continued to free up the inferior aspect of the third part from the retroperitoneal attachment, from right to left and toward the ligament of Treitz (Fig. 2C). This ligament was then ligated from the superior duodenal fossa to straighten out the duodenojejunal junction (Fig. 2D). To completely rotate the distal third part and fourth part downward and toward the right, away from the aortomesenteric angle, we sometimes had to sacrifice some small blood vessels between the duodenum and the tail of the pancreas (Fig. 2E). Care was taken not to injure the inferior mesenteric vein. To avoid the future risk of volvulus as well as to bring the center of gravity of the colon close to the aortomesenteric angle, the cecum was sutured into the splenic flexure, and the anterior free tenia of the ascending colon and that of the transverse colon were sutured together. The end result of our derotation procedure was a configuration similar to that seen in a congenital intestinal malrotation after the Ladd’s procedure with the entire duodenum to the right of the aortomesenteric angle and the entire colon to the left (Fig. 2F). If the derotation was successful, the duodenal distention immediately resolved with the passage of gas and liquid distally. This was an excellent predictor for the resolution of the symptoms after the surgery. We did not have adequate data on the operating time for the first group of patients; however, the average operating time for the latter six patients was 120 minutes (range: 90-150). Postoperatively, patients were discharged when they tolerated a regular diet, and they were followed weekly until asymptomatic, then every year until 21 years of age or lost to follow-up. Results
Over a 27 year period from 1974 to 2001, 15 patients (M:F = 1:3; mean age = 11.8) were diagnosed with SMAS based on clinical presentations and UGI (Table 1). A 6-month-old female who suffered intermittent postprandial bilious emeses since birth and failure to thrive was diagnosed initially with a duodenal atresia by UGI. However, on exploration the patient had the typical intraoperative findings of SMAS and responded to derotation. Of 16 patients diagnosed within this period, three (19%) responded to 4 to 6 weeks of nasojejunal feeding, one with typical cast syndrome and another with SMAS due to the compression from retroperitoneal lymphoma. Of 13 patients who underwent derotation, only one (7.7%) failed the derotation and required a gastrojejunostomy 6 weeks later, which resulted in resolution of the symptoms. Although the reason for the failure of this derotation procedure was unknown, it was likely due to the difficulty in separating the third portion of the duodenum from the body and tail of the pancreas without causing too much disruption in the blood supply to the distal duodenum. This probably resulted in an incomplete derotation. All other patients in this group became asymptomatic and began to gain weight approximately 2 weeks postoperatively. Two small bowel obstructions due to adhesions occurred in this group, one of who was the patient with the failed derotation. Both patients were treated with simple lysis of adhesions.
FIG. 2. Duodenal derotation procedure.
A cohort of six patients diagnosed by 3D CT was followed by our practice (Table 2). Most were female teenagers (M:F = 1:5) with the mean age of 15 years (range: 12-18), mean body mass index of 18 (range: 16-20), and mean duration of symptoms before the diagnosis of SMAS of 18 months (range 2-60). They all had multiple diagnostic studies before being referred. Interestingly, a 17-year-old female was diagnosed with biliary dyskinesia and underwent a laparoscopic cholecystectomy without relief of symptoms. On 3D CT, their aortomesenteric angles and distance averaged 18.2[degrees] (range: 16-20) and 4.8 mm (range: 2-8), respectively. All six failed conservative treatment consisting of small frequent meals, metoclopramide, and postural modifications for 4 to 6 weeks, and required an average of 5 days of hospital stay (range: 3-12) after the derotation. All six then became asymptomatic after an average of 14 days (range: 7-29) postoperatively. Other than one patient who developed mild gastroesophageal reflux symptoms after the surgery, no major surgical complications have been encountered at the mean follow-up of 4.37 years in this group.
TABLE 1. Characteristics of Patients with SMAS Diagnosed by UGl (1974-2001)
Overall, of 19 patients [M:F = 5:14; mean age: 14 years (range: 0.5-18)] undergoing derotation for SMAS, 18 (95%) became asymptomatic, with two (11%) long-term adhesive complications and no recurrence. We have observed no volvulus in either group thus far.
Discussion
Late in the fifth week of gestation, the midgut grows faster than the embryonic abdominal cavity and herniates through the umbilical cord. The superior mesenteric artery is the blood supply to the herniated bowel and the yolk sac. The herniated bowel rotates around the superior mesenteric artery axis 90 degrees counterclockwise so mat the future duodenum is to the right of the superior mesenteric artery and the colon to the left. During the tenth week, the proximal small bowel returns to the abdominal cavity, followed by the colon. During this retraction, the intestine rotates an additional 180 degrees counterclockwise so that the third part of the duodenum is posterior to the SMA and the transverse colon anterior. The duodenojejunal junction is tethered to the right crus of the diaphragm by the ligament of Treitz, a band of smooth muscle and fibrous tissue. As a result, the duodenal third portion is tightly secured between the angle formed by the aorta and the SMA, the aortomesenteric angle.
The cause of SMAS is likely multifactorial and includes both congenital and physiological components. We theorize that there are two major factors that contribute to the pathophysiology of SMAS. The first factor is a short ligament of Treitz, which, we assume, is a congenital factor. This can cause problems in one of two ways: 1) drawing the third portion of the duodenum upward toward the narrow part of the AMA, or 2) creating an acute bending angle of the small bowel right at the duodenojejunal junction. 15 The second factor is an increase in angular torque on the third portion of the duodenum. This factor can be eimer congenital or acquired. If we treat the small bowel and colon, as well as their associated mesenteries, as pendulums suspended by the SMA branches to the point where the SMA diverges from the aorta, then the angular torques exerted by the weights of the small bowel and colon on the third part of the duodenum are directly proportionate to length of the pendulums (the lengths of the SMA branches), me weights of me pendulums (me weights of the small bowel and colon as well as their associated mesenteries), and me sine values of the angles formed by the aorta and the SMA branches (essentially AMA) (Fig. 3). The smaller the angles, the larger are their sine values.
TABLE 2. Characteristics of the Patients with SMAS Confirmed by Computerized Tomography Arteriogram (2001-2007)
Based on the concept of angular torque, we can divide the causes of the SMAS into three different groups with a high aortomesenteric angular torque on the third portion of the duodenum. The first group has a large pendulum length, in other words, an elongated mesentery with the bowel contents sagging into the pelvic cavity. Wilkie refers to this group as having visceroptosis which can be either congenital or acquired.2 For instance, SMAS caused by acquired visceroptosis has been well described in patients undergoing protocolectomy with ileal J-pouch anastomosis.16 In the second group, an increased mass of the pendulum due to the large weights of the mesentery and the bowel contents secondary to factors such as tumors can theoretically augment the angular torque on the duodenum. To our knowledge however, SMAS simply due to mesentery or bowel tumors has not been reported in the literature. Most patients with SMAS belong to the third group with a severely acute AMA. This angle is supported by the mesenteric root fat pad. The reduction in this fat pad in patients with rapid weight loss due to eating disorders17 or gastric bypass18 can result in a reduction in the AMA, and as a sequela, SMAS. The well-known Cast Syndrome in spinal surgeries is SMAS caused by the reduction in the AMA associated with manipulations of the vertebral column.7, 8 Aortic aneurysm can also reduce the AMA. 19 Other potential causes of a reduced AMA due to an extrinsic compression are mesenteric lymphadenopathy secondary to an infection or metastasis, and primary pancreatic, stomach, or colon malignancy. In the pediatric population, especially teenagers, SMAS is due to a rapid growth in height without an equivalent growth in weight. This may result in an elongated mesentery (the pendulum length) as well as the loss of mesenteric root fat pad (the pendulum angle). This may explain why most of our patients are teenagers experiencing growth spurts. Needless to say, SMAS likely develops as a combination of multiple congenital and physiological factors. The congenital predisposition has been supported by the findings of SMAS in a family cluster20 and in identical twins.21
FIG. 3. Pendulum concept of SMAS.
It is important to emphasize that SMAS is a compression phenomenon on the duodenum by the AMA, and not an ischemic phenomenon due to compression of the SMA by the duodenum. However, when the compressed duodenum becomes too severely dilated, it may exert compression on the SMA. This explains the occasional epigastric vascular bruits in some of our patients. Also, the compression on the duodenum in a true SMAS is often intermittent and incomplete. The patients are usually asymptomatic between the episodic attacks, and even during the attacks, gastric and duodenal contents can still slowly pass through the AMA. In such cases, we may appreciate a highpitched epigastric bowel sound on exam. We advocate the use of the terms primary and secondary SMAS where primary SMAS is defined as one without an associated disease process and secondary SMAS is associated with a clearly defined disease process. Pathophysiologically, patients with primary SMAS must have both attributing factors as already discussed: a short ligament of Treitz and an increased aortomesenteric angular torque which is not due to an organic disease such as tumor or retroperitoneal lymphadenopathy. Clinically speaking, these patients must have a typical presentation of SMAS and must undergo complete pre and intraoperative evaluations to rule out other organic causes of the symptoms. Most patients with primary SMAS turn out to be pediatric patients at their growth spurts or adult patients with a rapid weight loss. These are perfect candidates for a duodenal derotation procedure. On the other hand, if an SMAS can be attributed to any other organic disease, it should be considered as secondary SMAS. The treatment is then to provide aggressive nutritional support and to correct the underlying disease if possible. Two patients in our series are considered to have secondary SMAS: one with Body Cast Syndrome after a motor vehicle accident, and one with retroperitoneal lymphoma. Both responded well to nutritional support alone. Other examples of secondary SMAS are those with retroperitoneal tuberculosis, retroperitoneal sarcoma, or pancreatic tumor. If nutritional support fails to resolve the symptoms in these patients, a duodenojejunostomy procedure should be considered. A duodenal derotation can be technically challenged.
Traditionally, SMAS is a diagnosis of exclusion because me symptoms of SMAS can imitate many other common diseases such as gallbladder disease, peptic ulcer disease, irritable bowel syndrome, or gastroperesis.10 Therefore, most patients experience the symptoms of postprandial fullness, abdominal discomfort, and nausea for many months before SMAS becomes a part of the differential diagnosis. Up until the 1980s, UGI was the confirmatory test of choice for the syndrome. Many authors argue for strict UGI criteria which must show all of these five elements: 1) A dilatation of the 1st and 2nd parts of the duodenum, 2) An abrupt vertical or oblique compression of the 3rd portion, 3) Antiperistaltic flow of the contrast proximal to the compression, 4) Delay of transit of the contrast into the jejunum of at least 4 to 6 hours, and 5) A relief of the compression and symptoms in a knee-to-chest or left lateral decubitus position.10, 22 Even with this strict criteria, UGI does not seem to be sensitive enough for SMAS because the symptoms are often intermittent and are experienced in unpredictable ways. UGI is generally only appropriate during an active attack. To overcome this problem, some authors propose a concept of hypotonic duodenography where an antiperistaltic agent is used to slow down the evacuation of the duodenum to induce the symptoms during a UGI study.3, 23 This improves the sensitivity of the UGI study; however, it is nonphysiologic and may not reflect a true SMAS.4 Since the 1960s, angiographies have helped in delineating AMA, and in conjunction with UGI, measuring aortomesenteric distance (the distance between the aorta and the SMA where it passes over the third portion of the duodenum). The normal angle is estimated to be 25 to 60[degrees], with 7 to 22[degrees] to be considered as abnormal. The normal distance is estimated to be 10 to 28 mm, with 2 to 8 mm to be considered as abnormal.3, 23, 24 The major limitation of angiography is mat the angle and distance are usually derived from only one (usually lateral) view and may not represent the real angle and distance. The 3D CT solves this problem. A multiplanar reformatted reconstruction can be rotated using a maximum intensity projection protocol to find the largest values of the AMA and distance where the duodenum passes over.4 Moreover, the dilated duodenum can be evaluated in reference to the surrounding anatomic structures especially the aorta and the SMA.4 The ranges of normal and abnormal AMA and distance are comparable to those found on angiography; however, the aortomesenteric distance seems to be superior to the AMA in diagnosing SMAS.25 In fact, a cut-off value of 8 mm has up to 100 per cent sensitivity and specificity in predicting SMAS.26 In addition to the cut-off value of 8 mm, we also look for the signs of obstruction such as distended stomach, dilated proximal duodenum, abrupt compression of duodenum at the AMA, and minimal passage of contrast distal to the obstruction. As already mentioned, these signs may not always be present due to the intermittent nature of the disease, and a repeat study may be needed. They are, however, found in all of our six patients with 3D CT.
If exposure to iatrogenic radiation from 3D CT is a concern, especially in younger patients, abdominal ultrasonography with color Doppler or endoscopic ultrasonography can provide diagnostic information equivalent to mat of 3D CT.27, 28 However, these studies are operator-dependent and not readily available in most community hospitals.
In regard to treatment, our principal belief is that a true primary SMAS is transient. In other words, certain physiological or psychological issues aggravate the aortomesenteric angular torque on the duodenum in most patients with certain congenital predispositions to SMAS. We argue that these issues are either temporary or correctable. This concept is most applicable in teenagers, the most common presenting group, at their growth spurts. In fact, if these patients wait long enough until their weight growth catches up with the height growth, the mesenteric fat pad would increase, and the symptoms would spontaneously resolve. Therefore, the treatment of choice for all patients with SMAS is nutritional support, aiming at increasing the mesenteric fat pad, which in turn increases the AMA. Reportedly, this treatment has been up to 100 per cent successful in orthopedic patients with spinal surgeries.29, 30 In patients who can comply with a conservative regimen, small, frequent meals together with postprandial postural modifications such as side-lying or chest-to-knee and the use of properistaltic agents such as metoclopramide are recommended.9, 10 These postural modifications hypothetically increase the AMA. Younger children or critically ill patients may not be able to tolerate this regimen well. In such cases, a postobstruction or jejunal tube feeding and/or total parenteral nutrition may be indicated. These regimens must be instituted for at least 4 to 6 weeks before any consideration of a surgical approach.
Only three of our 22 patients (14%) responded to conservative treatment. These are critically ill, hospitalized patients with the nasojejunal feeding tubes sutured in their nose for several weeks. The rate of compliance with conservative treatments in our pediatric patients is low. These patients, in general, are highly functional at home and in school apart from intermittent severe postprandial symptoms. Active younger patients, who have difficulty following instructions, also have difficulty maintaining a nasojejunal tube in place for several weeks. Multiple reinsertions of the tube would result in an erratic feeding schedule. On the other hand, most of our patients are teenagers at growth spurts, who have no fear of surgery. Some actually are cheerleaders. Asking these patients to have a nasojejunal tube for several weeks is impossible. All of our patients and their parents generally agree to a several-week trial of multiple daily meals with high protein supplements, and most request a surgical treatment eventually.
Traditionally, the treatment for SMAS is duodenojejunostomy, which bypasses the obstructed third part of the duodenum. The best result is associated witii preoperative radiographic findings of a severe duodenal stasis.13 Laparoscopic cases have been reported.31 We believe that this approach is most appropriate for secondary SMAS with unbeatable underlying causes such as pancreatic cancer, mesenteric lymphadenopathy due to lymphoma and tuberculosis, and abdominal aortic aneurysm.
Other alternative surgical approaches have been reported in the literature. A gastrojejunostomy is recommended if both the stomach and the duodenum are severely dilated, or when the duodenum is ulcerated rendering a duodenojejunostomy unsafe.2, 32 Additionally, a reanastomosis of the duodenum anterior to the SMA has also been described.33
We have been promoting duodenal derotation as the primary surgical treatment for SMAS since 1974.14 The technique preserves the primary flow of the intestinal tract without an anastomosis. We believe this is most appropriate in primary SMAS, especially in pediatric patients. The procedure was pioneered by Strong34 in 1958 when he stressed the significance of the mechanical obstruction on the duodenum caused by a tight attachment of the third duodenal portion into an acute AMA. The same concept was actually touched upon by Wilkie2 30 years earlier. The attachment is maintained by the ligament of Treitz as well as by the adhesion of the duodenum to the retroperitoneal space and to the pancreas. The treatment, therefore, simply focuses on the release of this attachment by ligating the ligament of Treitz and liberating the third and fourth parts of the duodenum from the distal pancreas and from the retroperitoneum. Consequently, the distal duodenum becomes an intraperitoneal rather than a retroperitoneal organ. More importantly, this results in a rotation of the third and fourth portion as well as the mesentery downward and to the right of, and away from, the AMA. This rotation is in the direction opposite to that of the embryonic midgut rotation, hence, the term derotation. The procedure is simple and effective enough to have been performed laparoscopically in four patients, three of whom became asymptomatic.35 We follow this concept and technique with one modification: to also mobilize the colon to the left of the AMA. There are two major advantages of this modification. First, mobilizing the right colon and the mesentery off the right gutter would facilitate the access to the inferior aspect of the third duodenal portion, which in turn, facilitates the derotation process. Second, by fixation of the ascending colon to the transverse colon along the anterior free tenia starting with attaching the cecum to the splenic flexure and suturing toward the hepatic flexure, we theoretically reduce the pendulum length, which subsequently reduces the angular torque caused by the weight of the colon on the duodenum if an incomplete or unsuccessful derotation is to occur. The fixation also prevents the potential risk of a volvulus of the free segment of the colon. Despite the fact that it has never been done, we believe that this procedure is laparoscopically feasible.
There were only two long-term surgical complications observed in our study. One patient experienced mild symptoms of heart burn which were temporary and successfully treated with a proton pump inhibitor. Two patients with small bowel obstructions were found to have intra-abdominal adhesions which were successfully lysed. Although being a theoretical risk, no volvulus complication has been observed to date.
The major limitation of our study is the data on long-term follow- up. We attempt to correct this problem by monitoring the new cohort of patients diagnosed by 3D CT as long as we can. However, as with any observational study in the pediatric population, it is extremely difficult to obtain long-term data. Our surgical practice routinely follows our patients up to 21 years of age. However, most will be lost in followup due to family relocation, departure for college, marriage, and transfer of care to general surgeons.
Conclusion
With the availability of 3D CT as the new gold standard for the diagnosis of SMAS, we expect a more general acceptance of this disease entity. It is therefore important to distinguish between the primary and secondary conditions because the treatment options may vary depending on that distinction. In our opinion, SMAS in elderly patients should be considered as a sign rather than a disease, and an extensive workup should be undertaken to find the underlying cause. All patients with SMAS should have a trial of at least 4 to 6 weeks of conservative treatment with optimal nutritional support. A derotation procedure should be offered as an option for the patients with primary SMAS, especially the pediatric patients in whom the disease is mostly temporary. If the derotation fails to resolve the symptoms, a duodenojejunostomy or gastrojejunostomy is always possible at a later time.
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CHI D. HA, M.D., DOMINGO T. ALVEAR, M.D., F.A.C.S., DAVID C. LEBER, M.D., F.A.C.S.
From the Departments of Surgery, Pinnacle Health Hospitals, 201 S. Front Street, BMAB-9, Harrisburg, Pennsylvania
Presented at the Annual Scientific Meeting and Postgraduate Course Program, Southeastern Surgical Congress, Birmingham, AL, February 9-12, 2008.
Address correspondence and reprint requests to Chi D. Ha, M.D., Department of Surgery, Pinnacle Health Hospitals, 201 South Front Street, BMAB-9, Harrisburg, PA 17104. E-mail: ha_md@ surgeonsknot.com.
Copyright Southeastern Surgical Congress Jul 2008
(c) 2008 American Surgeon, The. Provided by ProQuest LLC. All rights Reserved.
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