Emergency laparoscopy. Technical support for the laparoscopic diagnosis of intestinal ischemia

Abdominal emergencies: diagnostic and therapeutic laparoscopy

BACKGROUND

Laparoscopy has been practiced in the management of emergencies resulting from inflammatory conditions, lumenal obstruction, perforation, vascular occlusion, and trauma. This article identifies and discusses controversial areas in the field, in particular surrounding the efficacy, cost effectiveness, and perceived advantages of laparoscopy in the evaluation and treatment of patients with acute abdominal conditions.

MATERIALS AND METHODS

Review and commentary on pertinent articles in the English language literature are presented.

RESULTS

Prospective randomized trials have been reported in the treatment of some disorders, but a lack of recommendations that are evidence-based has hindered more widespread usage of laparoscopy in an emergency setting. In addition, concerns have been raised that the creation of capnoperitoneum in the patient with established peritonitis may be detrimental with respect to potentiation of bacteremia and severe sepsis, and experimental studies have yielded conflicting data in this regard.

CONCLUSION

As such issues are resolved, utilization of laparoscopy is likely to increase substantially as expertise is acquired. A minimal-access approach carries less morbidity and may offer other practical advantages in terms of surgical technique and application. When surgical intervention is appropriate, laparoscopy is now preferred for acute biliary disease. Female patients of reproductive age with acute appendicitis may benefit, particularly if there is preoperative diagnostic uncertainty. Selected cases of intestinal obstruction and visceral perforation presenting soon after symptom onset and in whom shock is absent may also be amenable to laparoscopic repair. Its use in the treatment of most trauma patients and patients with generalized peritonitis or hemodynamic instability is not recommended at present.

Tomographic bioluminescence imaging by use of a combined optical-PET (OPET) system: a computer simulation feasibility study

The feasibility and limits in performing tomographic bioluminescence imaging with a combined optical-PET (OPET) system were explored by simulating its image formation process. A micro-MRI based virtual mouse phantom was assigned appropriate tissue optical properties to each of its segmented internal organs at wavelengths spanning the emission spectrum of the firefly luciferase at 37 degrees C. The TOAST finite-element code was employed to simulate the diffuse transport of photons emitted from bioluminescence sources in the mouse. OPET measurements were simulated for single-point, two-point and distributed bioluminescence sources located in different organs such as the liver, the kidneys and the gut. An expectation maximization code was employed to recover the intensity and location of these simulated sources. It was found that spectrally resolved measurements were necessary in order to perform tomographic bioluminescence imaging. The true location of emission sources could be recovered if the mouse background optical properties were known a priori. The assumption of a homogeneous optical property background proved inadequate for describing photon transport in optically heterogeneous tissues and led to inaccurate source localization in the reconstructed images. The simulation results pointed out specific methodological challenges that need to be addressed before a practical implementation of OPET-based bioluminescence tomography is achieved.