The Long Magenstrasse with pyloroplasty as functional gastric bypass: 6-years experience, 308 operations

doi:10.4236/health.2010.28138

Paper Menu >>

Journal Menu >>

Vol.2, No.8, 935-940 (2010)

doi:10.4236/health.2010.28138

HEALTH

Openly accessible at

The Long Magenstrasse with pyloroplasty as functional

gastric bypass: 6-years experience, 308 operations

Carlo Vassallo1*, Giovanni Berbiglia1, Matteo Carena2

1Centro Multidisciplinare per la cura dell’Obesità, Istituto di Cura “Città di Pavia”, Unità operativa di Chirurgia Generale IIa, Pavia,

Italy; *Corresponding Author: carlo.vassallo@grupposandonato.it

2Centro Multidisciplinare per la cura dell’Obesità, Istituto di Cura “Città di Pavia”, Pavia, Italia

Received 8 March 2010; revised 12 April 2010; accepted 13 April 2010.

ABSTRACT

Background: The Long Magenstrasse with py-

loroplasty as functional Gastric Bypass (briefly

LMGBP) procedure for morbid obesity may re-

duce the incidence of side effects associated

with gastric restrictive and malabsorptive sur-

gery, particularly on quality of life and long-term

nutritional insufficiency. In follow-up to pre-

liminary findings in 34 patients, we report the

results of an additional 274 LMGBPs performed

over the past 3 years. Methods: Between Octo-

ber 2003 and 2009, 308 patients were treated

with the LMGBP. 149 patients underwent open

procedures; 74, hand-assisted laparoscopic sur-

gery (HALS); and 85 were operated laparo-

scopically. 17% had ≥ 125 mg/dl glycemia, 43%

sleep apnea, 38% hyperlipidemia, 12% hyperu-

ricemia, and 58% arterial hypertension under

treatment. Results: The mean BMI of 256 pre-

operatively normoglycemic patients at 1 year

was 29 (range 26-31); 27 (25-30) in 45 patients at

3 years; and 27.5 (26-30) in 12 patients at 5 years.

Mean BMI of 53 preoperatively hyperglycemic

patients (≥ 125 mg/dl) at 1 year (21 patients) was

32 (29-34), and at 3 years (9 patients), 32.5 (30-

33). 15 patients with preoperative type 2 diabe-

tes under oral treatment required no therapy 3-6

months after surgery. Patients reported consid-

erable appetite reduction with rapid satiety but

maintained good nutrition with no supplemen-

tation. There was no mortality. Conclusions:

Safe and effective sustained weight loss, posi-

tive metabolic changes, and appetite diminution

with rapid satiety were seen after LMGBP.

Keywords: Morbid Obesity Bariatric Surgery Partial

Vagotomy Pyloroplasty Magenstrasse and Mill

Gastric Bypass

1. INTRODUCTION

Relative to the bariatric/metabolic surgical technique

employed, morbidly obese patients may experience

long-term side effects that negatively influence their

metabolism and quality of life; these include vomiting,

diarrhea, osteoporosis, anemia, and malnutrition. Bariat-

ric surgeons have long sought an operation that results in:

steady weight loss that approaches the patient’s goal

weight between 12 and 18 months; technical simplicity

with only moderate risk with laparoscopy; freedom to

consume most foods with reduced hunger and early sati-

ety; and nutritional sufficiency, requiring no supplemen-

tation.

In our institute we have performed bariatric surgery

for 32 years. During this time, we have operated with

different techniques, both gastric restrictive and malab-

sorptive, on 2,419 morbidy obese and super-obese pa-

tients [1-6], with an average of 103 patients each year

from 1988 through 2009. During the last 6 years, we

have increasingly performed the Long Magenstrasse

with pyloroplasty as functional Gastric Bypass (briefly

LMGBP) (Figure 1), an operation comprised of 2 out-

moded surgical techniques augmented for use in combi-

nation in the LMGBP. The Magenstrasse and Mill

(M&M) procedure [7-9] originated in 1987 by Johnston

et al., in which a vertical gastric tunnel (the “magen-

strasse,” or street of the stomach) is created from the

angle of His to the antral mill (the “mill”) 6 cm from the

pylorus, is extended in the “Long Magenstrasse” to 3 cm

from the pylorus [10]. A pyloroplasty pneumatic or digi-

toclassic completes the LMGBP.

Our choice to continue performing the LMGBP has

been reinforced by the good results obtained to date, the

relative simplicity of this technique, and patient satisfac-

tion with an improved quality of life. In comparison with

the Roux-en-Y gastric bypass (RYGB) technique, the

LMGBP is performed only on the stomach and involves

no anastomosis to the small intestine, minimizing time in

C. Vassallo et al. / HEALTH 2 (2010) 935-940

936

the operating room and surgical risk. Compared to the

sleeve gastrectomy (SG) technique, the LMGBP requires

no destruction of tissues, and no formation of a distal

gastric pouch, thus, reducing the probability of progres-

sive pouch dilatation with could need to be correct with

duodenal swich procedure.

This study aimed to confirm, after more than 300

LMGBP operations on morbidly obese and super-obese

patients, what we optimistically observed after the first

34 operations [10]: that safe and effective weight loss

could be achieved with the LMGBP in concert with ex-

cellent reduction or resolution of the comorbidities of

obesity, few and mild complications in the perioperative

period and long term, and an improved quality of life for

patients.

2. MATERIALS AND METHODS

2.1. Patients

Between October 2003 and October 2009, 308 morbidly

obese and super-obese patients were operated with the

LMGBP technique (14 to rectify failed gastric restrictive

operations). In a population comprised of 72% females,

patients’ mean preoperative body mass index (BMI,

kg/m2) was 45 and their mean age was 39 years. Seven-

teen percent of the 308 patients before surgery had gly-

cemia ≥ 125 mg/dl: Five percent (15 patients) had type 2

diabetes mellitus (T2DM) by standard criteria [12-14]

under oral treatment, 1% (3 patients) had type 1 diabetes

under insulin treatment, and the remaining 11% (35 pa-

tients) had glycemia that fluctuated between 125 mg/dl

and 150 mg/dl, not under any pharmacologic treatment.

During the first year of our experience we excluded as a

precaution the overt T2DM patients, for whom we be-

lieved another kind of operation was preferable. Thus,

for this group, pertinent data are available only for the

last 5 years.

Forty-three percent of all patients had obstructive

sleep apnea, 38% hyperlipidemia, 12% hyperuricemia,

and 58% arterial hypertension under treatment. All pa-

tients underwent presurgical internal screening. Forty-

five percent of patients could not progress directly to

bariatric surgery, requiring prior pneumologic-metabolic

rehabilitation for a period of 6 months to 1 year, some-

times with intermittent hospitalization and use of a con-

tinous positive airway pressure (C-PAP) machine.

2.2. Surgical Technique

The technical features of this operation are the ones de-

scribed in our 2007 study [10]; we summarize them here,

as this procedure has not been widely performed.

The LMGBP is initiated with the performance of a

pyloroplasty. We carried out the pyloroplasty using a

variety of access techniques. In the 74 hand-assisted

laparoscopy (HALS) cases and 149 open operations

performed with median paraxiphoid or left sub costal

mini-laparotomy, a digitoclassic approach (i.e., applica-

tion of external pressure to interrupt the pyloric muscle

by manipulating it between the thumb and index finger)

[15,20] was used to effect the pyloroplasty. In the 85

laparoscopic cases, a pneumatic endoscopic approach

(i.e., pyloric dilatation balloon introduced through the

gastroscope and inflated up to 2 cm in diameter with an

internal pressure of 6 atmospheres) was employed gen-

erally on the day before the surgical procedure. With this

approach you must use a balloon with uniform dilatation

without clepsydra effect.

A 36-Fr. endogastric bougie was introduced to cali-

brate the Long magenstrasse against the lesser curvature

of the stomach. A gastric window was subsequently cre-

ated beside the bougie approximately 9-10 cm proximal

to the pylorus using a 21-mm circular stapler. Gastric

division was accomplished first, distally, from the gastric

window to 3 cm proximal to the pylorus with Echelon-

60 2.0-mm green reloads performing a alimentary way

and a secretory way (Figure 1), and next, proxi- mally,

from the window up to the angle of His with 3-4 addi-

tional Echelon-60 1.8-mm golden reloads.

The gastric division to the angle of His creates a sev-

erance of the left vagus nerve and its innervation of the

greater curvature of the stomach. This, in essence, con-

stitutes a partial vagotomy.

2.3. Experiences and Specific Remarks to

Make the Carrying Out of the

Operating Procedure ‘Long

Magenstrasse’ Simpler.

1) In the open technique the patient should be placed

on the operating table in anti-trendelemburg position,

almost in orthostatic.

2) For a better surgical field and a smaller percentage

of after surgery laparocele (from 6% to 2 %), it is pref-

erable in open surgery to use a left sub-costal laparo-

tomy with section of the rectus muscle instead of the

median xipho-umbilical.

3) In the H.A.L.S. for the introduction of the hand we

carry out a right sub- costal laparotomy of 6-7 cm and

three left accesses with two trocars of 10-12 mm and one

of 15 mm through which, removing momentarily the

trocar, the 21 circular enters for the making of the gastric

antrum window at 10 cm from the pylorus.

4) In video laparoscopy five accesses are necessary

with two troncars of 5 mm, two of 10-12 mm and one of

15 mm.

PS: If you consider it opportune we can send you the

video tapes of the H.A.L.S. technique (3) and of the

video laparoscopy (4).

C. Vassallo et al. / HEALTH 2 (2010) 935-940

937

3. RESULTS

3.1. Weight Loss and Comorbidity Resolution

The best weight-loss results were seen in the 256 pa-

tients with a mean initial BMI of 45 and normal presur-

gical glycemia. These patients’ BMI dropped under 30

(range 26-30) after 1 year with a sustained effect at 3 and

5 years in those individuals available for follow-up

(Figure 2). In the 53 patients with presurgical hypergly-

cemia ( ≥ 125 mg/dl), 21 cases at 1 year and 9 cases at 3

years had a mean BMI of 32 and 32.5, respectively

(Figure 3). All 35 patients with glycemia between 125

mg/dl and 150 mg/dl not under treatment and the 15

patients with overt T2DM experienced normalization of

their glycemia and were able to suspend therapy com-

pletely within 6 months of the operation. The value of

HbA1c in those 15 patients within 6 months of the op-

eration have stabilized at the mean of 5.8 %. The 3 pa-

tients with type 1 diabetes were able to halve their insu-

lin dose within 6 months of surgery (Table 1).

The effects on other comorbidities 1 year after surgery

included complete resolution in 90% of patients of sleep

apnea syndrome, in 68% of those with arterial hyperten-

sion, in 93% of those with hyperlipidemia, in 91% with

hyperuricemia (Table 2), and in 100% of those with

oligo-amenorrhea.

3.2. Nutrition

At 1-, 3-, and 5-year time points, no substantive meta-

bolic-nutritional sequelae, such as anemia, bone disease,

or peptic ulceration, were observed. Iron, calcium, pro-

teins, vitamin B12, and folates remained consistently in

the normal range (Table 2), despite patient reports of

decreased appetite, rapid satiety, and limitation of food

intake. There was also no increase in parathormone at 1,

3, and 5 years following surgery. There has been no need

for mineral or vitamin supplementation in any patient.

3.3. Mortality and Morbidity

There have been no mortalities within the series of

LMGBP patients over the course of our 6-year experi-

ence. No postoperative nasogastric tube was used fol-

lowing the LMGBP procedures. Only 12 patients re-

quired a subhepatic drain.

Two perisurgical complications occurred. The first

complication was a 2-3-cm dehiscence of the suture in

the antrum in 1 of the first operated cases. This patient

required reoperation on postoperative day 4 to incorpo-

rate a manual suture. (Initially, we used a green 45-mm

endoscopic stapler with a double line of staples; today,

mechanical suturers with 3 lines of staples are more re-

liable, even at the antral level, where the gastric wall is

thicker.) The second complication was in a patient with

Table 1 Patients with glycemia ≥ 125 mg/dl (17%) operated

with the Long Magenstrasse with pyloroplasty as functional

Gastric Bypass (LMGBP).

Before

operation

N. patients

= 53 (%)

months

N. pa-

tients =

1 year

N. pa-

tients =

3 years

N. patients

= 9

T2DM

under oral

treatment

15 (5%) 13 sus-

pended

7 sus-

pended

3 sus-

pended

DM1

under insulin

treatment

3 (1%) 3 halved 2 halved 1 halved

Intolerance

of glucose

not under

treatment

35 (11%)

27 gly-

cemia

< 110

mg/dl

12 gly-

cemia

< 110

mg/dl

5 glyce-

mia

< 110

mg/dl

T2DM, type 2 diabetes; DM1, type 1 diabetes.

Table 2 Comorbidities in 308 patients operated with the

LMGBP

Before

opera-

tion

N. pa-

tients

6 months

N. patients

At follow-up

(% resolu-

tion)

1 year

N. patients

at follow-up

(% resolu-

tion)

3 years

N. patients

at follow-up

(% resolu-

tion)

Hyperten-

sion 179 145 (62%) 85 (68%) 29 (73%)

Sleep ap-

nea 132 107 (88%) 64 (90%) 19 (94%)

Hyperlipi-

demia 116 93 (82%) 56 (93%) 16 (93%)

Hyperu-

ricemia 36 29 (86%) 19 (91%) 7 (80%)

an increasingly severe stenosis of the Long Magen-

strasse (alimentary way) at the third distal that required a

latero-lateral anastomosis with the gastric antrum (sec-

retory way) on day 7, transforming the operation into a

M&M. In the immediate post-surgical period, the patient

had 20% atelectasis at the base of the lungs with moder-

ate hyperthermia; this was resolved on day 3-4 by means

of antibiotic therapy and respiratory care. There was no

thrombophlebitis or pulmonary embolism, probably ow-

ing to the short length of the operation (about 1 hour),

early ambulation to void in the afternoon, and heparin

prophylaxis.

We had 1 complication at 1 year, due to insufficient

digitoclassic pyloroplasty. In this patient, we had to per-

form a surgical pyloroplasty. Finally, our rate of ventral

hernia in the “open” operations was 9%.

4. DISCUSSION

A BMI reduction from 45 to approximately 30 at 1 year

C. Vassallo et al. / HEALTH 2 (2010) 935-940

938

Figure. 1. The Long Magenstrasse Gastric Bypass (LMGBP).

Figure 2. Mean BMI before LMGBP surgery and at follow-up in patients with normoglycemia

Figure 3. Mean BMI before LMGBP surgery and at follow-up in patients with hyperglycemia.

Openly accessible at

C. Vassallo et al. / HEALTH 2 (2010) 935-940

939

Table 3. Average nutritional levels before and after LMGBP.

Before

Opera-

tion

months

year

years 5 years

N. patients 308 251 147 55 12

Iron (µg/dl) 74.81 76.27 74.75 81.83 78.24

Ca (mg/dl) 8.98 9.42 9.24 9.25 8.91

Vit. B12

(pg/ml) 414.12 405.75345.13 304.25321.36

Folic acid

ng/ml) 5.94 5.70 4.18 5.15 4.90

Total pro-

teins (g/dl) 7.3 6.8 7.6 7.1 6.9

following LMGBP surgery in both normoglycemic and

hyperglycemic patients was achieved; this is comparable

to the weight reduction attained with other primary bari-

atric/metabolic procedures. In patients who were avail-

able for follow-up, weight loss appeared to be sustained

at 3 and 5 years, while established T2DM was resolved

(i.e., requiring no medication) in all cases. LMGBP was

associated with resolution of 68% to 100% of all other

comorbid disease.

Significant weight loss with LMGBP, coupled with its

moderate surgical risk, very low complication profile,

and the satisfaction of patients, suggests a viable ad-

vance in bariatric surgical technique. This procedure can

be employed to advantage and perhaps may be prefer-

able to the technically more complex RYGBP, which is

not without nutritional-metabolic side effects, or the SG

[21,22], which, though conferring the benefit of restric-

tion without a foreign body, involves tissue destruction

and creation of a distal gastric pouch subject to possible

dilatation. In its most radical and effective form, the SG

is a real sub-total gastrectomy that, in the instance of

intercurrent illnesses requiring added nourishment,

makes restoration impossible.

The LMGBP technique may not be readily embraced

by surgeons due to its incorporation of the pyloroplasty,

particularly digitoclassic pyloroplasty, a procedure in-

volving manipulations of the pyloric muscle that are

difficult to calibrate and that require the introduction of a

hand into the abdomen. Since acquiring the technology

to perform endoscopic pneumatic pyloroplasty, inde-

pendent of the primary surgery, it is no longer necessary

to perform pyloroplasty manually. We have had to repeat

the pneumatic pyloroplasty procedure in only 3 patients

6 months after the operation.

An effective pyloroplasty is essential for the LMGBP

to work. It is the digitoclassic or pneumatic pyloroplasty

in an antrum subjected to vagotomy to 3 cm from the

pylorus that enables partially digested food to freely pass

through the duodenum in a modulated way, without the

exaggerated movement induced by some surgical py-

loroplasties that can result in the dumping syndrome. A

smoother transit of food prevents reflux of the alimen-

tary bolus into the gastric corpus/fundus, effecting a true

bypassing of the stomach and reduction of the secretion

of ghrelin [23-26]. Moreover, recent studies seem to

show that the increased speed of food transit through the

jejunum induces an increased peptide YY (PYY) secre-

tion [27], an early feeling of satiety, and stimulation of

increased secretion of glucagon-like peptide (GLP-1) at

the ileal level [13,28], lessening insulin resistance. Duo0

denal biliary reflux into the stomach is nonexistent be-

cause of the narrowness of alimentary and secretory way

wich convly in the prepyloric mill (Figure 1). One year

after the surgery the gastroscopy routine do not show

bile o phlogosis in the praepiloric “Mill”.

The correct functioning of the LMGBP also relies

upon extension of the partial vagotomy from the angle of

His to 3 cm from the pylorus. This added length, we

believe, secures a dramatic decrease of 60% to 80% in

hydrochloric peptic secretion [15-20]. The small per-

centage of residual hydrochloric peptic secretion main-

tains digestive activity, mixing ingested food at the level

of the prepyloric mill. Patients report that their interest in

food is diminished.

A limitation of this study was its loss to follow-up of a

number of patients. In addition, few patients in our series

have been followed yet for more than 3 years. Continued

study is required on a meaningful number of patients

over the long term, the results of which should be com-

pared with those of other primary bariatric/metabolic

procedures.

After 6 years of experience performing the LMGBP

and following patients, some out to 3 and 5 years, we

can confirm that the technique has some very definite

assets: For the surgeon, LMGBP is relatively straight-

forward to perform open or laparoscopically, no foreign

bodies need to be introduced, and there is no potentially

dilatable gastric pouch. For the anesthetist, LMGBP is

an efficient procedure (50-90 minutes), and it rarely re-

quires post-surgical intensive care. For the follow-up

team, LMGBP produces a patient who is uncomplicated

to care for. And, most important, for the patient, LMGBP

is a relatively positive experience; he or she achieves a

weight loss that is satisfactory and sustainable with easy

food compliance, no observable metabolic and nutri-

tional imbalance, and no need for supplementation [29].

In conclusion, the patient operated with a LMGBP

does not become a formerly morbidly obese patient, but

rather, a person whose metabolism functions more like

that of a normal-weight individual. This form of func-

tional gastric bypass appears to achieve and maintain

weight loss safely without marked nutritional perturba-

tion, and without the psychological and behavioral strain

C. Vassallo et al. / HEALTH 2 (2010) 935-940

940

Openly accessible at

of treating the nutritional imbalances that often accom-

pany restrictive or malabsorptive surgery.

REFERENCES

[1] Baltazar, A., Bou, R., Cipagauta, L.A., et al. (1995) “Hy-

brid” bariatric surgery: Biliopancreatic diversion and

duodenal swich-preliminary experience. Obesity Surgery,

5(4), 419-423.

[2] Bastaroli, E., Della Valle, A., Vassallo, C., et al. (1993)

Reflections on 4 years’ activity of an interdisciplinary

center for the treatment of obese patients. Obesity

Surgery, 3(3), 285-288.

[3] Marceau, P., Biron, S., Bourque, R.A., et al. (1992)

Biliopancreatic diversion with a new type of gastrectomy.

Obesity Surgery, 3(1), 29-35.

[4] Vassallo, C., Andreoli, M., La Manna, A., et al. (2001) 60

reoperations on 890 patients after gastric restrictive sur-

gery. Obesity Surgery, 11(6), 752-756.

[5] Vassallo, C., Negri, L., Della Valle, A., et al. (1999) Di-

vided vertical banded gastroplasty either for correction or

as a first-choice operation. Obesity Surgery, 9(2), 177-

179.

[6] Vassallo, C., Negri, L, Berbiglia, G., et al. (2004) Bilio-

pancreatic diversion with transitory gastric restriction

and duodenal bulb preservation: 88 patients since 1992.

Obesity Surgery, 14(6), 773-776.

[7] Johnston, D., Dachtler, J., Sue-Ling, H., et al. (2003) The

Magenstrasse and Mill operation for morbid obesity.

Obesity Surgery, 13(1), 10-16.

[8] Johnston, D. and Sue-Ling, H. (1995) Surgical treatment

of morbid obesity. In: Cushieri, A., Moosa, A.R., Giles,

G.R., Eds., Essential Surgical Practice. Butterworth-

Heinemann, London, 1036-1044.

[9] Robinson, J., Sue-Ling, H. and Johnston, D. (2006) The

Magenstrasse and Mill procedure can be combined with

a Roux-en-Y gastric bypass to produce greater and sus-

tained weight loss. Obesity Surgery, 16(7), 891-896.

[10] Vassallo, C., Berbiglia, G., et al. (2007) The Long Ma-

genstrasse and Mill operation with pyloroplasty: Pre-

liminary results. Obesity Surgery, 17(8), 1080-1083.

[11] Carmichael, A.R., Sue-Ling, H.M. and Johnston, D.

(2001) Quality of life after the Magenstrasse and Mill

procedure for morbid obesity. Obesity Surgery, 11(6),

708-715.

[12] Mason, E.E. (2005) The mechanisms of surgical treat-

ment of type 2 diabetes. Obesity Surgery, 15(4), 459-461.

[13] Rubino, F., Forgione, A., Cummings, D.E., et al. (2006)

The mechanism of diabetes control after gastrointestinal

bypass surgery reveals a role of the proximal small intes-

tine in the pathophysiology of type 2 diabetes. Annals of

Surgery, 244(5), 741-749.

[14] Scopinaro, N., Papadia, F., et al. (2008) A comparison of

a personal series of biliopancreatic diversion and litera-

ture data and gastric bypass help to explain the mecha-

nisms of resolution of type 2 diabetes by the two opera-

tions. Obesity Surgery, 18(8), 1035-1038.

[15] Siewert, J.R. and Muller, C.. (1983) Terapia chirurgica

dell’ulcera duodenale non complicata. In: Allgöwer, M.,

Harder, F., Hollender, L.F., Peiper, H.J. and Siewert, J.R.,

Eds. Trattato di Gastroenterologia Chirurgica. Antonio

Delfino Editore, Rome, 2, 463-466.

[16] Amdrup, E. and Jensen, H.E. (1973) One hundred pa-

tients five years after selective gastric vagotomy and

drainage for duodenal ulcer. Surgery, 74, 321-325.

[17] Goligher, J.C., Pulvertaft, C.N., et al. (1972) Five to

eight years results of truncal vagotomy and pyloroplasty

for duodenal ulcer. British Medical Journal, 1(5791),

7-13.

[18] Johnston, D., Humphrey, C.S., et al. (1970) Should the

gastric antrum be vagally denervated if it is well drained

and in the acid stream? British Journal of Surgery,

58(10), 725-731.

[19] Thompson, J.D. and Galloway, J.B.W. (1979) Vagotomy

and pyloric dilatation in chronic duodenal ulceration.

British Medical Journal, 1(6176), 1453-1455.

[20] Taylor, T.V., Lythgoe, J.P., et al. (1990) Anterior lesser

curve seromyotomy and posterior truncal vagotomy versus

truncal vagotomy and pyloroplasty in the treatment of

chronic duodenal ulcer. British Journal of Surgery, 77,

1007-1009.

[21] Almogy, G. Crookes, P.F., Anthone, G.I., et al. (2004)

Longitudinal gastrectomy as a treatment for the high-risk

super-obese patient. Obesity Surgery, 14(4), 492-497.

[22] Morínigo, R., Lacy, A.M., et al. (2006) GLP-1 and

changes in glucose tolerance following gastric bypass

surgery in morbidly obese subjects. Obesity Surgery,

16(12), 1594-1601.

[23] Conce, M.E., Cottam, D. and Esplen, J. (2006) Is ghrelin

the culprit for weight loss after gastric bypass surgery? A

negative answer. Obesity Surgery, 16(7), 870-878.

[24] Frühbeck, G., Diaz-Caballero, A., Gil, M.J., et al. (2004)

The decrease in plasma ghrelin concentrations following

surgery depends on the functional integrity of the fundus.

Obesity Surgery, 14(5), 606-612.

[25] Garcia-Fuentes, E., Garrido-Sanchez, L., et al. (2008)

Different effect of laparoscopic Roux-en-Y gastric by-

pass and open biliopancreatic diversion of Scopinaro on

serum PYY and ghrelin levels. Obesity Surgery, 18,

1424-1429.

[26] Roth, C.L., Reinehr, T., et al. (2009) Ghrelin and obes-

tatin levels in severely obese women before and after

weight loss after Roux-en-Y gastric bypass surgery.

Obesity Surgery, 19(1), 29-35.

[27] Reinehr, T., Roth, C.L., et al. (2007) Peptide YY and

glucagon-like peptide-1 in morbidly obese patients be-

fore and after surgically induced weight loss. Obesity

Surgery, 17(12), 1571-1577.

[28] Reavis, K.M., Hinojosa, M.W., et al. (2008) Single lapar-

oscopic incision transabdominal surgery sleeve gastrec-

tomy. Obesity Surgery, 18(11), 1492-1494.

[29] Schweitzer, D.H. and Posthuma, E.F. (2008) Prevention

of vitamin and mineral deficiencies after bariatric surgery:

Evidence and algorithms. Obesity Surgery, 18(11), 1485-

1488.