Diagnostic ultrasound ( PDFDrive )

CHAPTER 18 Organ Transplantation 641
A
B
FIG. 18.18 Inferior Vena Cava (IVC) Infrahepatic Anastomosis: Normal and Abnormal in Two Patients. Sagittal sonograms of IVC show
(A) a normal caliber at the anastomosis (arrows) and (B) narrowing at the anastomosis (arrows).
FIG. 18.19 Inferior Vena Cava (IVC) Suprahepatic Anastomotic
Stricture. Sagittal color Doppler sonogram of a stenosed segment of
the IVC shows aliasing produced by high-velocity turbulent low in both
the IVC and the hepatic vein. Spectral tracing shows a greater than
threefold velocity increase at the stenotic region (left arrow).
essential to facilitate early resection, ablation, or chemotherapy 26,43
(Fig. 18.27). As in the general population, transplant recipients
can develop any type of primary or secondary neoplasm within
the liver.
RENAL TRANSPLANTATION
Transplantation is the treatment of choice for many patients
with chronic renal failure (CRF) severe enough to warrant
dialysis. he only contraindications to transplantation are unsuitability
for general anesthesia or surgery, preexisting infection or
malignancy, and a risk of recurrent renal disease (e.g., active
vasculitis or oxalosis). Before transplantation, a suitable donor
must be obtained with appropriate human lymphocyte antigen
(HLA) matching with the recipient. 44
As the number of patients with CRF continues to rise, the
major limitation for expanding transplant programs is the shortage
of suitable donor kidneys. his organ shortage has resulted in
an increasing number of renal transplantations from living related
donors. hese donors may include family members or close
friends with a long-standing relationship with the recipient. he
average life expectancy for a cadaveric allograt is 7 to 10 years,
whereas that for a live donor allograt is 15 to 20 years. 44
Regardless of whether a cadaveric or live donor allograt is
used, the cost-beneit ratio of a functioning successful transplant
far outweighs that of a patient with persistent CRF, so multiple
health care resources are targeted to ensure high rates of success.
Ultrasound is the most valuable noninvasive imaging modality
in monitoring the renal transplant.
Surgical Technique
Detailed sonography of the renal transplant requires knowledge
of the surgical procedure used in most institutions as well as the
postsurgical anatomic relationships. he right or let lower
quadrant is selected for the incision, based on the patient’s prior
surgical history and the surgeon’s preference. Usually, the right
lower quadrant is selected because the right iliac vein is more
supericial and horizontal on this side of the pelvis, facilitating
creation of a vascular anastomosis. 45,46
he type of arterial anastomosis used depends on whether
the allograt is cadaveric or living related and on the number