The document discusses renal vascular anatomy and its implications for surgery. It notes that the renal arteries typically enter the kidney through the hilum and branch into segmental arteries that do not anastomose. It also describes variations such as accessory renal arteries. The segmental arteries further branch within the kidney and an avascular plane exists between anterior and posterior branches. Venous drainage parallels the arterial supply. Imaging like CTA can accurately map the vasculature preoperatively to aid surgery. Understanding variations and collateral circulation is important for procedures like donor nephrectomy.

1. RENAL VASCULAR ANATOMY:
SURGICAL CONSIEDERATIONS
Dr. Prateek Laddha
CMC Ludhiana

2. Body wall
• Perirenal
fat capsule
Renal
artery
Renal
vein
Inferior vena cava
Aorta
• Fibrous
capsule
• Renal fascia
anterior
posterior
Supportive
tissue layers
Body of
vertebra L2
Peritoneum
Peritoneal cavity
(organs removed)
Anterior
Posterior

3. Aorta
Renal artery
Segmental artery
Interlobar artery
Arcuate artery
Cortical radiate artery
Afferent arteriole
Glomerulus (capillaries)
Nephron-associated blood vessels
Inferior vena cava
Renal vein
Interlobar vein
Arcuate vein
Cortical radiate
vein
Peritubular
capillaries
and vasa recta
Efferent arteriole
Path of blood flow through renal blood vessels

4. Cortical radiate vein
Cortical radiate artery
Arcuate vein
Arcuate artery
Interlobar vein
Interlobar artery
Segmental arteries
Renal artery
Renal vein
Renal medulla
Renal cortex
Frontal section illustrating major blood vessels

5. RENAL VASCULAR ANATOMY
• The renal pedicle classically consists of a single artery and a single
vein that enter the kidney via the renal hilum .
• The renal arteries arise from the aorta at the level of the
intervertebral disk between the L1 and L2 vertebrae where the longer
right renal artery passes posterior to the inferior vena cava (IVC).
• Renal arteries give branches to the adrenal glands, renal pelves, and
proximal ureters.

6. • Blood supply of the kidney. A
and B, Segmental branches of
the right renal artery
demonstrated by renal
angiogram. C, Segmental
circulation of the right kidney
shown diagrammatically. Note
that the posterior segmental
artery is usually the first branch
of the main renal artery and it
extends behind the renal pelvis.
a, artery

7. • Figure 91.12 Segmental arterial
anatomy of the right kidney. (By
permission from Walsh PC, Retik
AB, Vaughan ED et al (eds) 2002
Campbell's Urology, 8th edn.
Philadelphia: Saunders.)

8. • After entering the hilum, each artery divides into five segmental end
arteries that do not anastomose significantly with other segmental
arteries.
• Therefore occlusion or injury to a segmental branch will cause
segmental renal infarction.
• Nevertheless, the area supplied by each segmental artery could be
independently surgically resected.
• The renal artery usually divides to form anterior and posterior
divisions.

9. • The anterior division supplies roughly the anterior two thirds of the
kidney, and the posterior division supplies the posterior one third of
the kidney.
• Typically, the anterior division divides into four anterior segmental
branches:
• apical
• upper
• middle and
• lower

10. • The posterior segmental artery represents the first and most constant
branch, which separates from the renal artery before it enters the
renal hilum.
• A small apical segmental branch might originate from this posterior
branch, but it arises most commonly from the anterior division.
• The posterior segmental artery from the posterior division passes
posterior to the renal pelvis while the others pass anterior to the
renal pelvis.

11. • If the posterior segmental branch passes anterior to the ureter,
UPJO may occur.
• In 25% to 40% of kidneys, anatomic variations in the renal vasculature
have been reported.
• Supernumerary renal arteries are the most common variation, with
reports of up to five arteries, especially on the left side.
• The main renal artery may manifest early branching after originating
from the abdominal aorta and before entering the renal hilum.

12. • These perhilar arterial branches should be detected in patients
undergoing evaluation for donor nephrectomy.
• An accessory renal artery may arise from the aorta, between T11 and
L4, and terminate in the kidney.
• Rarely, it may also originate from the iliac arteries or superior
mesenteric artery.

13. ACCESSORY RENAL ARTERIES
• Accessory renal arteries are seen in 25% to 28% of patients and are
considered the sole arterial supply to a specific portion of the renal
parenchyma, commonly the lower and occasionally the upper pole of
the kidney.
• These accessory renal arteries may contraindicate laparoscopic donor
nephrectomy and result in severe bleeding if they are injured during
endopyelotomy for UPJO.
• Multiple renal arteries that arise from the aorta or iliac arteries are
frequently seen in horseshoe and pelvic kidneys. In approximately 5%
of patients, the main and accessory right renal arteries pass anterior
to the IVC.

14. AVASCULAR PLANE OF BRODEL
• There is a longitudinal avascular plane (line of Brodel) between the
posterior and anterior segmental arteries just posterior to the lateral
aspect of the kidney through which incision results in significantly less
blood loss.
• However, this plane may have various locations that necessitate its
delineation before incision either by preoperative angiography or
intraoperative segmental arterial injection of methylene blue.
• This has important surgical implications. For example, during percutaneous
access into the kidney, posterior calyces along the line of Brodel are
preferred.
• Furthermore, during anatrophic nephrolithotomy (Boyce procedure), an
incision is made through this avascular plane.

16. • At the renal sinus, each segmental artery branches into lobar
arteries, which further subdivide in the renal parenchyma to form
interlobar arteries.
• These interlobar arteries progress peripherally within the cortical
columns of Bertin to give the arcuate arteries at the base of the renal
pyramids at the corticomedullary junction.

18. • Note the close relationship of the interlobar arteries to the infundibuli
of minor calyces. Interlobular arteries branch off the arcuate arteries
and move radially, where they eventually divide to form the afferent
arterioles to the glomeruli.
• Each afferent arteriole supplies a glomerulus, one of approximately 2
million glomeruli, where urinary filtrate leaves the arterial system and
is collected in the glomerular (Bowman) capsule.
• Blood returns from the glomerulus via the efferent arteriole and
continues as either secondary capillary networks around the urinary
tubules in the cortex or descends into the renal medulla as the vasa
recta.

19. VEINOUS DRAINAGE
• The renal venous drainage correlates closely with the arterial supply
• The exception that unlike the arterial supply, has extensive collateral
communication through the venous collars around minor calyceal
infundibula.
• Furthermore, the interlobular veins that drain the post-glomerular
capillaries also communicate freely with perinephric veins through
the subcapsular venous plexus of stellate veins.
• The interlobular veins progress through the arcuate, inter-lobar,
lobar, and segmental veins paralleling their corresponding arteries.

20. • Three to five segmental renal veins eventually unite to form the renal
vein. Because the venous drainage communicates freely forming
extensive collateral venous drainage of the kidney, occlusion of a
segmental venous branch has little effect on venous outflow.
• The right and left renal veins lie anterior to the right and left renal
arteries and drain into the IVC.
• Whereas the right renal vein is 2 to 4 cm long, the left renal vein is 6
to 10 cm. The longer left renal vein receives the left suprarenal
(adrenal) vein and the left gonadal (testicular or ovarian) vein.

21. • The left renal vein also may receive a lumbar vein, which could be
easily avulsed during surgical manipulation of the left renal vein.
• The left renal vein traverses the acute angle between the superior
mesenteric artery anteriorly and the aorta posteriorly.
• In thin adolescents, the left renal vein may get compressed between
the superior mesenteric artery and aorta, causing nutcracker
syndrome.
• In approximately 15% of the patients, supernumerary renal veins are
seen and often are retroaortic when present on the left.

22. • Accessory renal veins are more common on the right side, and the
most common anomaly of the left renal venous system is the
circumaortic renal vein, reported in 2% to 16% of patients.
• The retroaortic renal vein is less commonly seen than the
circumaortic vein, in which the left renal vein bifurcates into ventral
and dorsal limbs, which encircle the abdominal aorta.
• In retroaortic renal vein, the single left renal vein courses posterior to
the aorta and drains into the lower lumbar segment of the IVC.

25. IMAGING FOR RENAL VASCULAR ANATOMY:
• Doppler ultrasonography clearly identifies renal arteries at their origin
from the abdominal aorta .
• However, the main renal artery is often difficult to identify at baseline
ultrasonography.
• (CTA) is currently considered the gold standard to assess renal
arteries, with 100% sensitivity for identification of renal arteries and
veins.
• The 3D volume-rendered CTA has emerged as a fast, reliable, and
noninvasive modality that can reliably and accurately depict
• the number, size, course, and relationship of the renal vasculature.

26. • Arterial branches down to the segmental branches could be
identified, but vessels smaller than 2 mm could be missed.
• Magnetic resonance arteriography uses no ionizing radiation, does
not require arterial access, and includes different imaging techniques
to visualize renal vasculature.
• Contrast material can give faster, better resolution and more accurate
images without artifacts, inferior mesenteric artery and diaphragm),
with occasional additional drainage into the retrocrural nodes or
directly into the thoracic duct above the diaphragm.

27. • Right renal lymphatic drainage primarily goes into the right
interaortocaval and right paracaval lymph nodes (between common
iliac vessels and diaphragm), with occasional additional drainage from
the right kidney into the retrocrural nodes or the left lateral para-
aortic lymph nodes.

28. Vascular Complications
• Preoperative patient preparation
• history and physical exam to elicit any signs or symptoms of bleeding
dyscrasias
• work-up as needed by hematology should be performed as an uncorrected
coagulopathy is the only absolute contraindication for percutaneous renal
surgery
• Preoperative labs
• should include a prothrombin time/partial thromboplastin time
(PT/PTT),international normalized ratio (INR), complete blood count, and
serum electrolytes; and cross-matched blood should be available,
depending on the type of case.
• A preoperative urine culture should be negative.

29. • increased risk of hemorrhage are those with cardiac stents who are
unable to discontinue their antiplatelet medication prior to surgery
• The recommendations are as follows:
• antiplatelet agents, such as acetylsalicylic acid and clopidogrel, should be
stopped 10 days prior,
• warfarin 5 days prior, intravenous heparin 6 h prior, and low molecular weight
heparin 24 h prior to surgery.

30. Risk of hemorrhage with
renal procedures
Percutaneous renal biopsy
• A recent series reports the incidence of postbiopsy hemorrhage
(subcapsular and perinephric) to be lower (38.4%, 28 of 73) when
18G core needle biopsies are performed
• All hemorrhagic complications were managed conservatively; no
embolization or blood products were required in this series.

31. Percutaneous cryotherapy/radiofrequency ablation
• tumor size directly correlated with incidence of bleeding. Tumors with
a
• median size of 4.2 cm were associated with increased rates of
postablation hemorrhage when compared to tumors with a median
size of 2.6 cm (P > .05)
• When only a single probe is used, the rate of bleeding decreases to
0%.
• The use of multiple probes increases the degree of renal trauma and,
hence, the incidence of bleeding complications

32. Percutaneous nephrolithotomy
• that balloon dilators could decrease the risk of hemorrhage
associated with PCNL.
• factors associated with blood transfusions post PCNL and reported an
association with
• multiple punctures,
• renal pelvic perforation, inexperience,
• preoperative anemia and
• total blood loss
• Complications decrease with experience.

33. Management
• Venous haemorrhage
• Usually conservative
• AMPLATZ Sheath
• Nephrostomy tube 24 Fr .
• Kaye tamponade balloon catheter
• Perinephric hematoma
• triphasic abdominal CT scan to distinguish it from urinary leak
• transfusion of crystalloids and blood products
• conservative measures fail, then renal angiography and superselective
embolization should be performed in an attempt to identify and embolize the
bleeding arterial branches
• a return to the operating room for open exploration could be warranted

34. Post PCNL Haematuria
Before embolization After Embolization

35. Laparoscopic partial nephrectomy
• The majority of the literature regarding the complications of renal surgery
focuses on the comparison of open to laparoscopic techniques.
• When evaluating the hemorrhage associated with laparoscopic renal
surgery, it is important to keep it in perspective, because authors define
the term “hemorrhage” in multiple ways.
• For example, a hemorrhage that requires a blood transfusion differs
significantly from a hemorrhage that requires reoperative management or
embolization.
• Patients with immediate hemorrhaging postoperatively were managed
conservatively 2% (4 of 200), and delayed hemorrhaging occurred in 4% (8
of 200) of the patient.

36. ROBOTIC PARTIAL NEPHRECTOMY

37. • Arterial haemorrhage
• stabilization with crystalloids and blood products, patients should undergo
renal angiography and super-selective embolization
• The most common findings on angiography are
• arteriovenous fistulas,
• pseudoaneurysms, and
• lacerated renal segmental arteries (vessel cut-off)
• Grade V renal trauma still requires surgical exploration.

38. Vascular anatomy of the ureteropelvic
junction: importance for endopyelotomy
• Today, endopyelotomy is a common procedure for both primary and
secondary UPJO.
• The risk of injuring a large vessel during endopyelotomy can be
greatly reduced or even eliminated if the endourologist understands
and keeps in mind the 3D vascular relationships to the UPJ [44, 45,
51]. This section describes the vascular anatomy of the UPJ and this
should be used to perform endopyelotomy safely and efficiently.

39. Figure 6.41
(A) Anterior view of a right kidney
endocast (pelviocalyceal system
together with the intrarenal arteries)
shows a close relationship between
the inferior segmental artery and the
anterior surface of the ureteropelvic
junction (UPJ; arrow). u, ureter. (B)
Anterior view of a right kidney
endocast (pelviocalyceal system
together with the intrarenal veins)
shows a close relationship between a
vein draining the lower pole and the
UPJ (arrow). RV, renal vein; u, ureter
(reproduced from Sampaio and
Favorito [44], with permission).

40. • Anterior vascular ureteropelvic junction relationshiAps
• 65% of the endocasts there was a prominent artery, vein, or both vessels in
close relationship with theventral surface of the UPJ (Figures 6.41 and 6.42).
• Among these endocasts, the relationship was with the inferiorsegmental
artery in 45%

41. • To protect the arteries
from lesion, it has
been recommended
to examine via
intrarenal endoscopy
the area to be incised
for any arterial
pulsation and, if
detected, to avoid
incising that site.

42. • the exact role of crossing vessels
in obstruction and the success of
endopyelotomy are yet to be
determined.

43. • Thank You