A case of diaphragmatic hernia incarceration after a heart transplant operation

We report a case of a diaphragmatic hernia after a heart transplant operation. A 43-year-old woman, who underwent orthotropic heart transplantation for hypertrophic cadiomyopathy two year earlier, presented with vomiting and epigastric pain. A computed tomography scan showed that the stomach and transverse colon were dislocated in the left thoracic cavity. We diagnosed left diaphragmatic hernia incarceration and performed laparoscopic repair of the diaphragmatic hernia. A 12 × 8 cm diaphragmatic defect was found intraoperatively on the ventrolateral aspect of the left diaphragm, and the stomach with volvulus had herniated into the thorax through the defect. The hernia was considered to be iatrogenic. The diaphragmatic defect was large, and the diaphragm was thinning. We closed the defect by mesh repair. Laparoscopic mesh repair of the diaphragmatic hernia could be performed safely and with minimal invasiveness.     

In vivo oxidative cleavage of a pyridine-carboxylic acid ester metabolite of nifedipine

The pharmacokinetics of the primary pyridine metabolite of nifedipine (2,6-dimethyl-4-(2-nitrophenyl)-3,5-pyridinecarboxylic acid dimethylester) (M-0) and its [2H6]dimethylester analog ([2H6]M-0) were studied in male rats. A large, 5.8-fold deuterium isotope effect for the formation clearance of the monomethylester (M-1) was observed, which is strongly indicative for an oxidative reaction mechanism involving the abstraction of a hydrogen atom, presumably by cytochrome P-450. M-0 exhibited a high systemic blood clearance (104 +/- 27 ml/min/kg) (mean +/- SD) which was not significantly influenced by deuterium substitution (125 +/- 13 ml/min/kg). Its systemic clearance is presumably flow limited, and extrahepatic metabolism can be anticipated. The major metabolic pathway for M-0 in male rats seems to be a direct oxidation at the 2-methyl position and subsequently a rapid conversion of the unstable 2-hydroxymethyl-dimethylester to the lactone of the monomethylester (M-2), as has been shown by others in vitro. Non-oxidative ester cleavage of M-0 in our rats was negligible. Deuterium substitution of M-0 at the ester methyl groups induced "metabolic switching" in favor of the direct oxidation of M-0 to M-2.     

Localization and expression of chondromodulin-I in the rat cornea

The localization and expression in the rat cornea of chondromodulin-I (ChM-I), an inhibitory angiogenesis factor, were examined by immunohistochemistry, Western blot analysis, ribonuclease protection assay, and real-time PCR assay. We found immunoreactivity for ChM-I in the epithelial layer but not the stromal layer or endothelial layer in the cornea, in addition to the positive ChM-I immunoreactivity in other sites in the eye such as the sclera, retina, and ciliary body. The ChM-I immunoreactivity was most intense at the outside of the basal cells and in their cytoplasm while the intensity of the immunoreactivity decreased gradually from the wing cells to the superficial cells in the corneal epithelial layer. No reactivity however, was detected in the Bowman's membrane or conjunctival epithelial cells which had continuity with the corneal epithelial cells. The expression of ChM-I mRNA was demonstrated in the cornea at one-third less intensity than that in the sclera with choroids and retinal pigment epithelium by ribonuclease protection assay and real-time PCR. ChM-I in the corneal epithelial layer may prevent neovascularization and maintain avascularity in the cornea.     

Microsurgical anatomy of the abducens nerve

The aim of this study is to demonstrate and review the detailed microsurgical anatomy of the abducens nerve and surrounding structures along its entire course and to provide its topographic measurements. Ten cadaveric heads were examined using ×3 to ×40 magnification after the arteries and veins were injected with colored silicone. Both sides of each cadaveric head were dissected using different skull base approaches to demonstrate the entire course of the abducens nerve from the pontomedullary sulcus to the lateral rectus muscle. The anatomy of the petroclival area and the cavernous sinus through which the abducens nerve passes are complex due to the high density of critically important neural and vascular structures. The abducens nerve has angulations and fixation points along its course that put the nerve at risk in many clinical situations. From a surgical viewpoint, the petrous tubercle of the petrous apex is an intraoperative landmark to avoid damage to the abducens nerve. The abducens nerve is quite different from the other nerves. No other cranial nerve has a long intradural path with angulations and fixations such as the abducens nerve in petroclival venous confluence. A precise knowledge of the relationship between the abducens nerve and surrounding structures has allowed neurosurgeon to approach the clivus, petroclival area, cavernous sinus, and superior orbital fissure without surgical complications. Clin. Anat. 25:1030–1042, 2012. © 2012 Wiley Periodicals, Inc.     

Cortical Distribution of Fragile Periventricular Anastomotic Collateral Vessels in Moyamoya Disease: An Exploratory Cross-Sectional Study of Japanese Patients with Moyamoya Disease

BACKGROUND AND PURPOSE:Collateral vessels in Moyamoya disease represent potential sources of bleeding. To test whether these cortical distributions vary among subtypes, we investigated cortical terminations using both standardized MR imaging and MRA.MATERIALS AND METHODS:Patients with Moyamoya disease who underwent MR imaging with MRA in our institution were enrolled in this study. MRA was spatially normalized to the Montreal Neurological Institute space; then, collateral vessels were measured on MRA and classified into 3 types of anastomosis according to the parent artery: lenticulostriate, thalamic, and choroidal. We also obtained the coordinates of collateral vessel outflow to the cortex. Differences in cortical terminations were compared among the 3 types of anastomosis.RESULTS:We investigated 219 patients with Moyamoya disease, and a total of 190 collateral vessels (lenticulostriate anastomosis, n = 72; thalamic anastomosis, n = 21; choroidal anastomosis, n = 97) in 46 patients met the inclusion criteria. We classified the distribution patterns of collateral anastomosis as follows: lenticulostriate collaterals outflowing anteriorly (P < .001; 95% CI, 67.0–87.0) and medially (P < .001; 95% CI, 11.0–24.0) more frequently than choroidal collaterals; lenticulostriate collaterals outflowing anteriorly more frequently than thalamic collaterals (P < .001; 95% CI, 34.0–68.0); and choroidal collaterals outflowing posteriorly more frequently than thalamic collaterals (P < .001; 95% CI, 14.0–34.0). Lenticulostriate anastomoses outflowed to the superior or inferior frontal sulcus and interhemispheric fissure. Thalamic anastomoses outflowed to the insular cortex and cortex around the central sulcus. Choroidal anastomoses outflowed to the cortex posterior to the central sulcus and the insular cortex.CONCLUSIONS:Cortical distribution patterns appear to differ markedly among the 3 types of collaterals.

Collateral vessels in Moyamoya disease develop as the disease progresses.¹ Lenticulostriate arteries (LSAs), perforators from the posterior communicating artery (PcomA), and anterior and posterior choroidal arteries (choAs) are representative collateral vessels that supply the cortex.^2-4 Development of such collateral vessels represents a risk factor for intracerebral hemorrhage,^3,5-7 and these vessels have frequently been considered as the vessels responsible for bleeding in recent reports.^8-10 These collateral vessels connect with medullary arteries near the lateral ventricle and thus supply the cortex via the medullary arteries.^3,4 However, no reports have addressed the cortical distributions of these collateral vessels.Bypass surgery reduces the risk of rebleeding in patients with hemorrhagic onset of Moyamoya disease^7,11-13 and also shrinks collateral vessels in Moyamoya disease.^7,12,14,15 Augmentation of cerebral blood flow via bypass seems to decrease the necessity for development of collateral flow and shrinks existing collaterals.¹⁵ To shrink risky collateral vessels effectively and prevent hemorrhage, well-designed and planned bypass surgeries may be required.¹⁶ Comprehension of the nature and cortical distribution of collateral vessels may thus be clinically useful.MRA performed using a 3T scanner has proved useful for detecting the abnormally extended collateral vessels in Moyamoya disease.² We investigated the cortical distribution of collateral vessels using 3T MR imaging and MRA to clarify whether cortical distributions vary among anastomotic subtypes and to better understand collateral networks.     

Interventional Radiologic Treatment of Hepatocellular Carcinoma—A Cost Analysis from the Payer Perspective

PurposeTo determine whether there is a cost advantage for one of the three commonly performed interventional radiology (IR) procedures (chemoembolization, selective internal radiation therapy [SIRT], radiofrequency ablation [RFA]) in the treatment of hepatocellular carcinoma (HCC).Materials and MethodsA cost analysis from the payer perspective was performed. Primary data were collected from a university hospital, and sensitivity testing was done by comparing coding information obtained at two other tertiary care medical facilities. Medicare allowable reimbursements were used to estimate costs. Decision analytic models using decision tree analysis and Monte Carlo simulations were used to compare alternatives. Simulations were performed comparing all three procedures, followed by a two-way comparison of chemoembolization and SIRT.ResultsSimple decision tree analyses showed that RFA was less expensive compared with chemoembolization and SIRT. Monte Carlo simulations showed average reimbursements for each of the three procedures that was largely dependent on the number of repeat procedures required ($9,362 vs $30,107 vs $35,629 for RFA, chemoembolization, and SIRT; P < .001). When comparing only chemoembolization and SIRT, chemoembolization was the lower cost strategy in most scenarios, but SIRT was lower in cost in more than one-third of the simulations.ConclusionsRFA was the least costly of the three IR strategies in nearly all scenarios studied in these models. Although chemoembolization was less expensive than SIRT in most instances, Monte Carlo simulation showed a preference for SIRT in more than one-third of all scenarios. Sensitivity analyses showed that the most important variables assessed were the need for repeat procedures.