A method for coronary bifurcation centerline reconstruction from angiographic images based on focalization optimization.

A method for the reconstruction of a vessel centerline from angiographic images is outlined in this work. A typical coronary artery segment with bifurcations was emulated with a 3D printed static phantom and several angiograms were acquired at various angular positions on the C-Arm. The effectiveness of the reconstruction turned out to be largely influenced by the intrinsic parameters of the angiographic system, particularly the homogeneous coordinates system scaling factor λ. Therefore, recourse was made to a heuristic optimization method to estimate the optimal value of λ for each view. We measured the reliability of the reconstruction method by varying the fitness function of the optimization step and measuring the distances of 8 test points in comparison to the corresponding points identified in the µCT centerline. Preliminary results showed that, with an adequate number of views, the adoption of the optimal fitness function allowed the median distance error to be decreased below the acceptance threshold of 10%. As expected, the reliability of the method is improved by increasing the number of processed views.

On the electrical intestine turbulence induced by temperature changes.

Paralytic ileus is a temporary syndrome with impairment of peristalsis and no passage of food through the intestine. Although improvements in supportive measures have been achieved, no therapy useful to specifically reduce or eliminate the motility disorder underlying postoperative ileus has been developed yet. In this paper, we draw a plausible, physiologically fine-tuned scenario, which explains a possible cause of paralytic ileus. To this aim we extend the existing 1D intestinal electrophysiological Aliev-Richards-Wikswo ionic model based on a double-layered structure in two and three dimensions. Thermal coupling is introduced here to study the influence of temperature gradients on intestine tissue which is an important external factor during surgery. Numerical simulations present electrical spiral waves similar to those experimentally observed already in the heart, brain and many other excitable tissues. This fact seems to suggest that such peculiar patterns, here electrically and thermally induced, may play an important role in clinically experienced disorders of the intestine, then requiring future experimental analyses in the search for possible implications for medical and physiological practice and bioengineering.

Chronic oesophagitis in the cat.

BACKGROUND: Our understanding of the pathophysiology of gastro-oesophageal reflux disease (GERD) in man is limited. The aim of the present study was to establish a long-term (>1 year) animal model for reflux oesophagitis which would allow us to study various aspects of the development of chronic reflux oesophagitis. METHODS: Myotomy was carried out in the gastro-oesophageal junction in eight cats; seven other cats were sham-operated. Before the operation, and every 2 months thereafter, oesophagoscopy was carried out, biopsies were taken for histology, and manometry was performed to determine the lower oesophageal sphincter pressure (LESP). The cats were killed 1 year after the operation. RESULTS: The myotomy operation resulted in a significantly decreased LESP. In oesophageal biopsies from these cats, there was a varying degree of oesophagitis starting already 2 months after surgery. In six of the eight myotomized cats there was hyperplasia of the stratum basale, and cardiac type metaplasia was observed in two cats. The control cats showed no significant changes in LESP or in the histology of the oesophagus. CONCLUSIONS: In cats followed for more than a year, myotomy in the gastro-oesophageal junction results in reflux oesophagitis similar to that seen in patients with chronic gastro-oesophageal reflux.

Laparoscopic adrenalectomy for benign adrenal neoplasms.

BACKGROUND: Since first reported in 1992, laparoscopic adrenalectomy has been used to remove a wide variety of adrenal neoplasms. Indications for use of this technique have not been clearly defined, nor has it been demonstrated to be more cost effective than open adrenalectomy. METHODS: A retrospective comparison was made of 19 consecutive laparoscopic and open adrenalectomies performed in patients with benign adrenal neoplasms in a tertiary-care university teaching hospital over a 3-year period. RESULTS: The two groups were well matched for side of tumor and age. Laparoscopic adrenalectomy was completed in 11 of 12 patients in whom it was attempted. The laparoscopic group had significantly smaller tumor size; shorter operative time, postoperative ileus, and postoperative stay; and decreased operative blood loss and postoperative narcotic requirement. There were no significant differences between groups for operating room or hospital charges. CONCLUSIONS: Laparoscopic adrenalectomy is cost effective and should be the preferred treatment for patients with small benign adrenal neoplasms.

Laparoscopic complete excision of a splenic epidermoid cyst.

Splenic epidermoid cysts are rare lesions traditionally treated by splenectomy. Concerns about overwhelming postsplenectomy sepsis have led to the development of splenic preservation procedures in the treatment of cystic diseases of the spleen. We present the first case report of successful laparoscopic complete excision of a splenic epidermoid cyst.