Right Posterior Retroperitoneoscopic Adrenalectomy (PRA) for Adrenocortical Adenoma
Table of Contents
Posterior retroperitoneoscopic adrenalectomy (PRA) allows the surgeon to approach the adrenal gland through the back rather than the more traditional laparoscopic transabdominal adrenalectomy (LTA) approach. This technique was popularized in Germany but is being used increasingly throughout the United States. Our institution was one of the early adopters of this technique in the US, and we present such an operation here.
Given their location, deep in the retroperitoneal cavity, the adrenal glands are ideal targets for minimally invasive surgery to avoid the rather large incision an open technique would require. This began first with laparoscopic transabdominal adrenalectomy (LTA), but these also had limitations. As such, it led to the development of the posterior retroperitoneoscopic adrenalectomy (PRA) as an alternative approach, first described in 1995.1, 2 This approach allows for a direct approach to the adrenal glands without entering the peritoneal cavity, without the mobilization of adjacent organs, and avoiding potential hostile abdominal cavities from previous surgical interventions. Insufflation of the retroperitoneum does not affect a patient’s cardiovascular or respiratory parameters as much as intraperitoneal insufflation. Additionally, this approach allows access to bilateral adrenal glands if necessary, without repositioning.1, 3, 4
The patient is a 50-year-old female with biochemically unequivocal subclinical hypercortisolism and a right-sided adrenal tumor. She had symptoms of fatigue, palpitations, proximal muscle weakness, abdominal pain, and nausea. Her workup was significant for an AM cortisol level of 9.4 ug/dl (reference range 7.0–25.0 ug/dl). She had two dexamethasone suppression tests performed. After 11 PM administration of dexamethasone, her AM cortisol levels were measured at 8.0 ug/dl and 9.0 ug/dl indicative of a failure to suppress on both occasions. In addition, her ACTH was suppressed with an elevated 24h urine cortisol level. Urine catecholamines were normal.
Preoperative imaging included a CT and MRI of the abdomen. CT revealed a 2.9 x 3.1 x 3.8-cm right adrenal nodule in intracellular fat and characteristics of a benign adrenal adenoma. MRI showed a 3.4 x 3.2 x 0.9-cm right adrenal mass with signal dropout on opposed phase images.
CT and MRI are both widely accepted radiologic techniques for imaging normal and abnormal adrenal glands. Adrenal masses are commonly incidentally discovered on abdominal CT. CT densitometry is beneficial in these cases because it can distinguish an adrenal adenoma from metastases based on the attenuation of the masses. MRI is also useful in evaluating the characteristics of adrenal nodules. Specifically, chemical shift MRI is valuable in characterizing these nodules. Relative loss in signal intensity when comparing opposed phase and in phase images helps characterize these masses as benign. These techniques have comparable sensitivity and specificity for diagnosis.5, 6
We prefer the patient to undergo either adrenal protocol CT or MRI within approximately 3–6 months of planned operative intervention for operative planning. This patient was referred after having both CT and MRI showing a unilateral right adrenal mass with a normal-appearing left adrenal gland. That coupled with the hormonal workup negated the need for any further imaging.
With improvements in imaging modalities, what appear to be clinically silent adrenal tumors are found incidentally during cross-sectional imaging for unrelated issues. These adenomas may have autonomous secretion of cortisol only partially blocked by pituitary feedback leading to subclinical hypercortisolism or subclinical Cushing’s syndrome. It is possible that this is also a preclinical Cushing’s syndrome since these patients may progress to overt hypercortisolism.7 Since these patients are without overt symptoms, they are at risk for having had chronic exposure to mild cortisol excess, which can lead to classic symptoms of overt Cushing’s syndrome with time.8 Studies have shown consistently an association between subclinical Cushing’s syndrome and a manifestation of metabolic syndrome, hypertension, diabetes, and obesity being the most commonly seen.9, 10
Standard practice dictates adrenal nodules that are hormonally active are surgically removed to prevent the consequences of persistent hormone overproduction. Surgical resection of the culprit gland prevents sustained exposure to elevated hormone levels. In subclinical hypercortisolism, the benefit of that resection varies on the level of hypersecretion present. These patients have a higher incidence of hypertension, obesity, decreased bone density, and metabolic syndrome. Adrenalectomy ameliorates the biochemical abnormalities and as such, decreases the cardiovascular risk factors.8 In mild cases, observation is an option.11
The rationale for the surgical treatment of subclinical Cushing’s is to prevent the known sequelae of overt hypercortisolism. Those who have suppressed plasma ACTH and elevated urinary cortisol are close to progressing to overt hypercortisolism and as such, should be managed with surgical resection. Those with a milder disease but evidence of some metabolic syndrome, young age, or symptomatic bone disease should also have surgical management because of the risks of persistent exposure to elevated cortisol levels.11
LTA was first described in 1992. The first method described used conventional laparoscopic techniques with a transperitoneal approach. When compared with open surgery, this resulted in reduced postoperative pain, decreased blood loss, fewer wound complications, shorter hospital stays, and shortened recovery times.12 The PRA was then developed for more direct access to the adrenal glands. It was first described in 1995 and then further developed in Germany through the experience of Walz and his colleagues.2, 4, 13 Retrospective studies comparing LTA with PRA showed decreased operative times, decreased blood loss, and no difference in long-term outcomes with the posterior approach.
The direct approach into the retroperitoneum allows operators to avoid entering the peritoneum and the complications that could bring including adhesions, postoperative bowel obstructions, injury to intraperitoneal structures, and peritoneal carcinosis.4 The higher carbon dioxide insufflation pressures used for this approach have been shown to increase stroke volume, cardiac output, and mean arterial pressure. It also compresses small veins and minimizes bleeding, which aids in operative visualization.1 There is no distinct tumor size cutoff for PRA, but tumors over 4–6 cm can prove difficult.
This has been our institution’s preferred technique for minimally invasive adrenalectomy. The current patient had no complications following her PRA.
Since prone positioning is required for this procedure, it is performed under general anesthesia with endotracheal intubation.
PRA requires the patient to be placed in the prone jackknife position after induction of general anesthesia and endotracheal intubation. A Cloward table with Cloward Surgical Saddle is used to allow the abdomen to hang anteriorly. That, combined with the jackknife positioning, opens and decreases the pressure of the retroperitoneum. The face, arms, legs, and pressure points are all padded with the elbows, knees, and hips bent at 90 degrees. The external landmarks identified for optimal port placement are the iliac crest, the tip of the 12th rib, and the edge of the perispinous muscles. The initial incision is placed just inferior to the tip of the 12th rib. Scissors are used to sharply divide the soft tissue and enter the retroperitoneum. Dissection is just past the mandible, with care being taken not to dissect to superficial penetrating skin. The operator’s finger is then used to bluntly clear a space and guide the placement of 5-mm ports medially and laterally, both angled at about 30 degrees and aimed toward the position of the adrenal gland. A 10-mm balloon port is then placed in the initially placed middle incision. The retroperitoneum is then insufflated with carbon dioxide through high flow tubing with an insufflation pressure of 25 mmHg.
A 5-mm 30-degree scope is inserted in the central port, and a LigaSure device is used to create the retroperitoneal space. Creating the space, the operator then reveals the paraspinous muscles medially and then the kidney. The camera is then moved to the medial port, and the operator uses the LigaSure and a bowel grasper through the lateral and central ports. Dissecting over the superior pole of the kidney and along the paraspinal muscles medially, the adrenal gland is identified. The adrenal gland is mobilized, starting inferiorly, retracting the kidney downward. On the right, this dissection reveals the IVC off which the adrenal must be carefully dissected to reveal the adrenal vein. The vein is clipped and divided. The adrenal gland is mobilized medially and laterally, keeping the superior attachments to suspend the adrenal gland up during dissection. Finally, the superior attachments are taken to completely free the gland from surrounding tissue. It is then placed in an Endo Catch bag and removed through the central port site. The operative bed is inspected for hemostasis after decreased pressure, the ports are removed, and the incision is closed. If visual difficulties occur, other authors have described an additional incision above the hyoid bone, but we have not required this; additional ports do not fit within the vestibulum.
Final pathology revealed a 4.0 x 3.8 x 2.7-cm adrenocortical adenoma. Postoperative cosyntropin test performed on postoperative day one showed inadequate cortisol production confirming excess cortisol production. She was temporarily placed on low dose oral steroids and weaned off with recovery of adrenal function.
Andrew frame, Cloward Surgical Saddle, LigaSure device, and Endo Catch retrieval bag.
Nothing to Disclose.
The patient referred to in this video article has given their informed consent to be filmed and is aware that information and images will be published online.
- Callender GG, Kennamer DL, Grubbs EG, Lee JE, Evans DB, Perrier ND. Posterior retroperitoneoscopic adrenalectomy. Adv Surg. 2009;43(1):147-157. doi:10.1016/j.yasu.2009.02.017.
- Walz MK, Peitgen K, Hoermann R, Giebler RM, Mann K, Eigler FW. Posterior retroperitoneoscopy as a new minimally invasive approach for adrenalectomy: results of 30 adrenalectomies in 27 patients. World J Surg. 1996;20(7):769-774. doi:10.1007/s002689900117.
- Perrier ND, Kennamer DL, Bao R, Jimenez C, Grubbs EG, Lee JE, Evans DB. Posterior retroperitoneoscopic adrenalectomy: preferred technique for removal of benign tumors and isolated metastases. Ann Surg. 2008;248(4):666-674. doi:10.1097/SLA.0b013e31818a1d2a.
- Walz MK, Peitgen K, Walz MV, et al. Posterior retroperitoneoscopic adrenalectomy: lessons learned within five years. World J Surg. 2001;25(6):728-734. doi:10.1007/s00268-001-0023-6.
- Jhaveri KS, Wong F, Ghai S, Haider MA. Comparison of CT histogram analysis and chemical shift MRI in the characterization of indeterminate adrenal nodules. Am J Roentgenol. 2006;187(5):1303-1308. doi:10.2214/AJR.05.1022.
- Korobkin M. CT characterization of adrenal masses: the time has come. Radiology. 2000;217(3):629-632. doi:10.1148/radiology.217.3.r00dc52629.
- Terzolo M, Reimondo G, Bovio S, Angeli A. Subclinical Cushing's syndrome. Pituitary. 2004;7(4):217-223. doi:10.1007/s11102-005-4024-6.
- Starker LF, Kunstman JW, Carling T. Subclinical Cushing syndrome: a review. Surg Clin North Am. 2014;94(3):657-668. doi:10.1016/j.suc.2014.02.008.
- Terzolo M, Bovio S, Pia A, Osella G, Boretta G, Angeli A, Reimondo G. Subclinical Cushing's syndrome. Arq Bras Endocrinol Metabol. 2007;51(8):1272-1279. doi:10.1590/S0004-27302007000800013.
- De Leo M, Cozzolino A, Colao A, Pivonello R. Subclinical Cushing's syndrome. Best Pract Res Clin Endocrinol Metab. 2012;26(4):497-505. doi:10.1016/j.beem.2012.02.001.
- Reincke M. Subclinical Cushing's syndrome. Endocrinol Metab Clin North Am. 2000;29(1):43-56. doi:10.1016/S0889-8529(05)70115-8.
- Lairmore TC. Posterior retroperitoneoscopic adrenalectomy. In: Howe JR, ed. Endocrine and Neuroendocrine Surgery. Springer Nature; 2017:195-208.
- Mercan S, Seven R, Ozarmagan S, Tezelman S. Endoscopic retroperitoneal adrenalectomy. Surgery. 1995;118(6):1071-1076. doi:10.1016/S0039-6060(05)80116-3.
Cite this article
Erinjeri N, Carling T. Right posterior retroperitoneoscopic adrenalectomy (pra) for adrenocortical adenoma. J Med Insight. 2022;2022(244). doi:10.24296/jomi/244.
Table of Contents
- Patient positioning
- Mark Incisions
- Placement of Ports
- Development of Retroperitoneal Space
- Mobilization of Superior Pole of Right Kidney
- Mobilization of Plane Towards Liver
- IVC Exposure
- Approach Adrenal Vein Medially
- Approach Adrenal Vein Laterally if Necessary
- Adrenal Vein Ligation
- Port Site Hemostasis
- Suture Deep Layer
- Injection of Lidocaine
- Suture Superficial Layer
So posterior retroperitoneoscopic adrenalectomy was really popularized by Martin Waltz in - in Germany, and I spent some time working with him in Germany. It's now becoming a more common technique in the United States. It's been used for the last at least 15-20 years almost now at select centers in Europe. We've been using it for almost 8 years here at Yale, and we were one of the early adopters. This patient had subclinical Cushing's syndrome. She had an elevated urinary cortisol as well as had failed a 1-mg, low-dose dexamethasone suppression test twice. She had signs and symptoms that were consistent with slight cortisol overproduction, and this is her CT scan. So as you can see, on the right side, you have a homogeneous mass that measures about 4 cm. She had a previous MRI, and it actually showed some interval increase in the size of the tumor. So this particular case was relatively straightforward. There was a couple of modification to the technique; usually, I identify and ligate the right adrenal vein from the medial side, meaning towards the muscle, but the way the tumor was lying - I released the superior attachments first, such that I then could get good visualization of the adrenal vein, which was really the very last part of the operation where the adrenal vein was clipped, which was then done from the lateral side, meaning the liver side.
So we're doing a right posterior retroperitoneoscopic adrenalectomy. As you can see, the patient is in the prone position, intubated, all the paddings to make sure she doesn't have any neurovascular injuries during the operation. She's on what's called an Andrew Frame and the Cloward Saddle, so the key is to try to make sure that her back is in a flat position. Her legs are down here. She has a Foley catheter in place.
So we're marking out - so this is the midline of her back here - the lumbar spine. This is the iliac crest. This is the paraspinous muscle that goes all the way up here, and here I marked out the 11th and the 12th rib. So the 10-mm port is going to be right underneath the ribs, so I'm feeling for the rib right there. And then we're going to make a 10-mm incision right here, and then the 5-mm incision is going to be about here and the other 5-mm incision here. So the adrenal gland is going to be located up here, so it's important when you place these ports that, especially for the 5-mm port, that you have a little angle up towards the adrenal. So you don't want to place them straight in, 90°, but rather about 30° like so. And this port points towards the adrenal, so this is an about 30° angle as well.
So we're starting. Incision. So this incision is done about 5 mm below that rib, and I need to make it big enough so I can fit my finger. And then so I'm feeling for the rib right there. So that's a perfect location. So now I'm getting down through the retroperitoneal - layers here. Just need to go a little deeper. And a little bit deep. Okay, so this is all done by feel, and it's important to go straight down, but then - now I got my finger in here, so point it up towards the adrenal gland. I can feel for the edge of the paraspinous muscle. So the 5-mm port is going to be in here, and I can do a fair amount of this dissection bluntly with my finger just to break up some of the adhesions here. Okay? So I'll take the Bovie now. So I want to try to put this port as lateral as I can but not into the muscle. So right there - and then this port, again, pointing towards the adrenal gland. Okay.
And the key is to place this into my finger but without sticking my finger, so this is all done by palpation, so that's perfect right there. So I don't want to put the ports too far in because there's not a lot of working space. So same thing here, okay. Very nice, okay. And then we're going to use this port that has a little balloon, so we always want to check that first. That's for it to keep - stay in place. Okay, so - again, placing that. Because that will make sure it doesn't move around. Make sure that that's tight there, and then we'll take the port cleaner. Okay. All right, so I'll take the camera now. Okay, nice.
Okay, so the first order of business again here is just to identify your instruments. So as you can see, now I start seeing the paraspinous muscle, which is exactly what I want to see. Okay, so the first part of the dissection is just to identify the paraspinous muscle. Then, we start seeing the kidney right here. And then I'm just going to open up a few more of these cells here, so I'm going to switch the camera view around, and then just take down some of these attachments here. So sometimes patients with cortisol production can, you know, classically have some obesity, this particular patient is relatively slender, but she also doesn't have a massive amount of cortisol overproduction.
So as you can see, I'm just mobilizing the superior pole of the kidney right here, coming around on each side. Okay, so I got that quite, quite well done, so now we have the retroperitoneal space mobilized. So now we're going to switch that camera into the lateral 5 port, so let's clean that up. All right, so - we got a great view here now. So I want you to do that same thing when I come in and out - just when I come in and out - yeah. Yep. So we do a whole lot of dissection here on the kidney without even seeing the adrenal. It's important to mobilize the entire superior pole. Okay, now we start - I'm just going to move that a little bit.
All right, so just show me here a little bit. All right, so now we're mobilizing the plane towards the liver. All right, let me move that kidney a little bit there. Yep. All right, just come in and show me here. All right, so just follow the paraspinous muscle up here. Okay, so come back here. Okay. We just want to stay right here. We're going to mobilize the plane on the liver here a little bit more.
Okay, so - all right, so we start seeing the tumor right there. Come in and show me there. All right, so we start seeing the adrenal tumor right there, so we're going to - so the IVC is going to be down here. Let's have some suction now. All right, so - okay. So we stay - here you see the edge of the adrenal, so the key is to stay below that so you don't get into the adrenal gland. Okay. All right, let's switch to suction. Yeah, stay right there. We've got a good view here. Yep, yep, yep. Now down here is the vena cava, so we're going to stay - yep, you find that mobilized branch. You very gently dissect on top of the IVC here. And I'm sort of moving the tissue and lift it away from the IVC as I do that.
Same thing - and then, now we can start taking all these small vessels going into the adrenal. All right, come back now. Again, I'm avoiding whenever I can to grab the actual adrenal. You're bumping into me a little bit now, so maybe come back a little bit then - let's change your angle. So now we start seeing the mass here. Let's see right down here. So I gently lift that tissue. Yeah, come in a little bit. So I can free this up following the muscle, it'll help me move the whole mass medially. Take down some more of these attachments here. All right, come back now. We're making some good progress here, so then the adrenal vein is going to be up underneath the mass, so I'll patiently follow the IVC up. Again, gentle dissection. If you do have a tear into the IVC, it can be relatively easily fixed with a clip. Come a little closer. The key is to maintain the high CO2 pressure because as soon as you release, the patient bleeds out, so you maintain the pressure and then - clip it, or suture it, or whatever you got to do. Okay. All right, I'll start thinking we're getting up. Can you sneak underneath there? That looks like the vein is going to come up - off up there, but we need a little bit more mobilization to do that safely. So, come back. We're going to do a little bit more mobilization on this side here. Okay, so come a little closer here. Okay. So tumor is heading up there, so - come back here. Okay, and swing it along, so switch it all the way up like that. I want to see the top of it. Push this down, Connie - push this down. All right, so we got the mass here, and then I'm just gently going to lift the mass up, and then - all right, so I need you to sneak underneath. Underneath you? Well, I need to see - get a - I need to get an ex - I need to see that from - I need to see the corner there. Yeah. It's too fussy, it's not… Okay. Okay. Yeah, stay where we are - don't jump around. Okay, come back a bit. I don't love that angle yet, so come back - get clean. Okay. This looks like a typical benign adrenocortical adenoma. As you can see, it separates nicely. Okay, there's a little abnormal adrenal above it there, so… Okay. Okay, so can you sneak in under - so you got to figure out a way to sneak in underneath and show me the corner there. All right, so stay right there, now don't give up on this view. Yeah. All right, come - so let's do that again. Let's try to get that… Yeah, so I need to see that. All right, so… So where is the IVC heading, you know? I just want to make sure I'm not pulling up the whole IVC. So, you know, I want to sort of come here, right? But, where - where is the - so can you follow this up? Is the edge heading down right there? I think it's sort of heading down right there. Yeah, let's flip it around and see.
Yeah, okay. So I'm going to do something I don't usually do, but with this particular case, just to delineate - push, push this in - I'm going to mobilize it from superiorly first just to see that vein better. All right, come in. Okay. Now, we can see the vein better from this angle. Usually, it's easier to see it from the other angle, but her anatomy is such that the vein in this particular case is going to be easier to just do last here. So come back a little bit. Just because of this nodularity here. All right, so slide around. So here is the IVC heading down there and adrenal vein heading in right here. All right, so… Okay. All right, so slide that in there. Yep, okay. So…
Yep. Okay. Okay, LigaSure. Your clips are closed. No, they're perfect. Oh. Okay, so come back now. I think we're free. Okay.
So again, when I grab the gland, I never - I don't want to grab the tumor. I just grab the fat around it, so switch that over. I'll take an Endo Catch. Slide it in there. Push down on it - the angle - yep, there we go - beautiful. Okay now - yeah, okay. Okay. All right, so gas off and all that. Gas off, please. Hold this. Yep. Okay. All right, lights on. Get this out. Yeah, so get rid of all that stuff. There we go. All right, so right adrenal for permanent.
So at the end of the case now, we're just checking for hemostasis as well as those clips on the IVC. All good. There's just a little bit of bleeding from the muscle there. So here's the completed adrenalectomy on the right side. So her right adrenal vein just came a little bit more lateral, so it was actually easier to ligate it from the lateral side - i.e. the liver side - as opposed to the muscle side. But here, you see that the IVC is completely dissected out. You had the two clips on the - on the adrenal vein sitting right there. And the entire adrenal gland is removed. All right, we're all done.
So here is the right adrenal vein. All right, so we're ligating the right adrenal vein here. And then I'm just going to ligate that side.
So as you can see, this was a right posterior retroperitoneoscopic adrenalectomy for about a 4-cm right adrenal tumor. Posterior retroperitoneoscopic adrenalectomy has several advantages versus traditional laparoscopic transabdominal approaches. As you can see, the dissection is more direct as you put in the ports, you get right on top of the kidney and can dissect out the adrenal so you don't need to - as you have to do it laparoscopically - dissect out and mobilize the entire liver on the right side, and on the left side, the spleen and the pancreatic tail. It's especially advantageous in patients that have had previous abdominal operations and have a lot of adhesions, and you can stay in the retroperitoneum away from those adhesions. Another advantage is for bilateral tumors. So as you can see, the operation is fast. It's remarkable how little pain the patients have compared to laparoscopic procedures. So whenever possible, our preferred technique here at Yale is through the posterior retroperitoneoscopic approach because of less pain for the patient, swifter operation. As you can see, we're doing three adrenalectomies today, and we'll be done just after lunch. The laparoscopic transabdominal adrenalectomy is still a good operation, and is particularly used for larger tumors where the retroperitoneal space is too small to have good mobility. In terms of training for this technique, many endocrine surgery fellowships around the country offer this technique, so that's a great way to learn posterior approaches to the adrenal gland. Spending some time in a proctoring setting is always a possibility. If a surgeon has significant experience with laparoscopic surgery, the learning curve is pretty quick. It does require some new anatomical thinking and getting used to working in the - in a very small space. After having done 10 to 20 of these operations, I think most well-trained laparoscopic endocrine surgeons can adopt this technique, and the learning curve flattens out. In terms of outcomes, most published studies show similar outcomes in terms of complication rates compared to transabdominal surgery, but clearly, the operative length is shorter, and it seems like the patient has less pain and returns faster to work postoperatively.