The diagnosis of benign hepatic tumors as hepatic adenoma (HA) and focal nodular hyperplasia (FNH) remains a challenge for clinicians and surgeons. The importance of differentiating between these lesions is based on the fact that HA must be surgically resected and FNH can be only observed. A series of 23 female patients with benign liver tumors (13 FNH, 10 HA) were evaluated, and a radiologic diagnostic algorithm was employed with the aim of establishing preoperative criteria for the differential diagnosis. All patients were submitted to surgical biopsy or hepatic resection to confirm the diagnosis. Based only on clinical and laboratory data, distinction was not possible. According to the investigative algorithm, the diagnosis was correct in 82.6% of the cases; but even with the development of imaging methods, which were used in combination, the differentiation was not possible in four patients. For FNH cases scintigraphy presented a sensitivity of 38.4% and specificity of 100%, whereas for HA the sensitivity reached 60% and specificity 85.7%. Magnetic resonance imaging, employed when scintigraphic findings were not typical, presented sensitivities of 71.4% and 80% and specificities of 100% and 100% for FNH and HA, respectively. Preoperative diagnosis of FNH was possible in 10 of 13 (76.9%) patients and was confirmed by histology in all of them. In one case, FNH was misdiagnosed as HA. The diagnosis of HA was possible in 9 of 10 (90%) adenoma cases. Surgical biopsy remains the best method for the differential diagnosis between HA and FNH and must be performed in all doubtful cases. Surgical resection is the treatment of choice for all patients with adenoma and can be performed safely. With the evolution of imaging methods it seems that the preoperative diagnosis of FNH may be considered reliable, thereby avoiding unnecessary surgical resection.

To define the role of the renal nerves in renal sodium-retaining edema-forming states, experiments were conducted in conscious chronically instrumented rats with congestive heart failure (myocardial infarction), nephrotic syndrome (adriamycin injection), and hepatic cirrhosis (common bile duct ligation). In each experimental model, renal excretion, as water or sodium, of an acutely administered oral or intravenous isotonic saline load was significantly less than that in control rats. Bilateral renal denervation of the experimental rats restored their renal excretory response to that of the control rats. In addition, in response to the acute administration of a standard intravenous isotonic saline load, the decrease in efferent renal sympathetic nerve activity was significantly less in all three experimental models compared with that of control rats. These results suggest that the impaired ability to excrete an acute isotonic saline load in these experimental models is partially dependent on an increase in basal efferent renal sympathetic nerve activity that fails to suppress normally in response to the isotonic saline load.

No abstract

The indications for segmental liver resections are increasing. This type of procedure can be performed by deep wedge transparenchymal transection or by the intrahepatic approach, reaching the portal pedicle through the hilar plate. We devised a systematized way to perform such an operation.Design: Original surgical technique.Patients and Methods: Fourteen consecutive patients (8 men and 6 women; mean age, 55 years) underwent right segmental liver resections between July 1, 2001, and July 31, 2002. Seven patients had liver metastasis, 3 had primary liver cancer, 3 had benign lesions, and 1 had gallbladder cancer. The surgery was performed by making 3 small incisions around the hilar plate. With a stan-

Laparoscopic liver resection (LLR) has been progressively developed along the past two decades. Despite initial skepticism, improved operative results made laparoscopic approach incorporated to surgical practice and operations increased in frequency and complexity. Evidence supporting LLR comes from case-series, comparative studies and meta-analysis. Despite lack of level 1 evidence, the body of literature is stronger and existing data confirms the safety, feasibility and benefits of laparoscopic approach when compared to open resection. Indications for LLR do not differ from those for open surgery. They include benign and malignant (both primary and metastatic) tumors and living donor liver harvesting. Currently, resection of lesions located on anterolateral segments and left lateral sectionectomy are performed systematically by laparoscopy in hepatobiliary specialized centers. Resection of lesions located on posterosuperior segments (1, 4a, 7, 8) and major liver resections were shown to be feasible but remain technically demanding procedures, which should be reserved to experienced surgeons. Hand-assisted and laparoscopy-assisted procedures appeared to increase the indications of minimally invasive liver surgery and are useful strategies applied to difficult and major resections. LLR proved to be safe for malignant lesions and offers some short-term advantages over open resection. Oncological results including resection margin status and long-term survival were not inferior to open resection. At present, surgical community expects high quality studies to base the already perceived better outcomes achieved by laparoscopy in major centers' practice. Continuous surgical training, as well as new technologies should augment the application of laparoscopic liver surgery. Future applicability of new technologies such as robot assistance and image-guided surgery is still under investigation.