Combination of electrohydraulic lithotripsy and laparoscopy for gallbladder access in type III Mirizzi syndrome.

INTRODUCTION: A 50-year-old Japanese man presented with obstructive jaundice. We performed endoscopic retrograde biliary drainage before biliary decompression. CT showed a thickened gallbladder wall with low-density areas and a 35-mm gallstone; the stone was impacted in the gallbladder neck and cystic duct. The patient was therefore diagnosed with Mirizzi syndrome (type II or III) and scheduled for laparoscopic treatment. We performed subtotal cholecystectomy and intraoperative choledochoscopy because we recognized a fistula between the gallbladder and common bile duct preoperatively. MATERIALS AND SURGICAL TECHNIQUE: We opened the ductus choledochus, and a choledochoscope was introduced under laparoscopic guidance. An electrohydraulic lithotripsy probe with irrigation was passed through the choledochoscope to extract the gallstone. DISCUSSION: This fragmentation technique is effective for impacted large stones observed in Mirizzi syndrome. Therefore, electrohydraulic lithotripsy with laparoscopy is effective in cases of difficult gallbladder access such as that that occurs in type II or III Mirizzi syndrome.

A case of multiple inflammatory hepatic pseudotumor protruding from the liver surface after colonic cancer.

INTRODUCTION: Inflammatory hepatic pseudotumor (IHPT) is an important benign liver disease because it is difficult to clinically and radiologically distinguish from malignant tumors. PRESENTATION OF CASE: Here, we describe a case of a 67-year-old male patient diagnosed with multiple inflammatory hepatic pseudotumors. The patient had undergone left hemicolectomy for descending colonic cancer (T3 N0 M0 stage IIA) 2 years prior. He underwent segment 6 and segment 7 partial hepatectomy because of suspected liver metastasis. The patient had an unremarkable postoperative course and was discharged 7days after surgery. Marked infiltration of inflammatory cells was observed on histological examination. The patient was finally diagnosed with IHPT of the fibrohistiocytic type. DISCUSSION: Repeated imaging studies over 1 month showed the spontaneous regression of the hepatic tumors. Therefore, knowledge regarding this condition is necessary to allow for treatment, even in the absence of experience. During examination, it may be important to ascertain lesion size. Moreover, percutaneous needle biopsy and follow-up examinations are necessary for cases of suspected IHPT. CONCLUSION: Hepatectomy should be considered if the lesion is suspected to be an IHPT.

Free boundary problem for cell protrusion formations: theoretical and numerical aspects.

In this paper, a free boundary problem for cell protrusion formation is studied theoretically and numerically. The cell membrane is precisely described thanks to a level set function, whose motion is due to specific signalling pathways. The aim is to model the chemical interactions between the cell and its environment, in the process of invadopodia or pseudopodia formation. The model consists of Laplace equation with Dirichlet condition inside the cell coupled to Laplace equation with Neumann condition in the outer domain. The actin polymerization is accounted for as the gradient of the inner signal, which drives the motion of the interface. We prove the well-posedness of our free boundary problem under a sign condition on the datum. This criterion ensures the consistency of the model, and provides conditions to focus on for any enrichment of the model. We then propose a new first order Cartesian finite-difference method to solve the problem. We eventually exhibit the main biological features that can be accounted for by the model: the formation of thin and elongated protrusions as for invadopodia, or larger protrusion as for pseudopodia, depending on the source term in the equation. The model provides the theoretical and numerical grounds for single cell migration modeling, whose formulation is valid in 2D and 3D. In particular, specific chemical reactions that occurred at the cell membrane could be precisely described in forthcoming works.