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41.

Background:

Reconstruction with microvascular free flaps is considered the reconstructive option of choice in cancer of the head and neck regions and breast. Rarely, there is paucity of vessels, especially the veins, at the recipient site. The cephalic vein with its good caliber and constant anatomy is a reliable recipient vein available in such situations.

Materials and Methods:

It is a retrospective study from January 2010 to July 2012 and includes 26 patients in whom cephalic vein was used for free-flap reconstruction in head and neck (3 cases) and breast cancers (23 cases).

Results:

All flaps in which cephalic vein was used survived completely.

Conclusion:

Cephalic vein can be considered as a reliable source of venous drainage when there is a non-availability/unusable of veins during free-flap reconstruction in the head and neck region and breast and also when additional source of venous drainage is required in these cases.KEY WORDS: Breast reconstruction, cephalic vein, free flap, head and neck reconstruction  相似文献   
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Multiple disorders may cause chronic pancreatitis (CP) through recurrent inflammation of the pancreatic parenchyma. Chronic calcifying pancreatitis caused by excessive alcohol intake accounts for most cases of CP. However, there are multiple other causes of CP, including obstructive chronic pancreatitis, autoimmune pancreatitis, groove pancreatitis, tropical, and hereditary pancreatitis. This article reviews the multiple imaging techniques, some of which are accepted as first-line modalities in patients with suspected CP, and the imaging features associated with the different causes of CP.  相似文献   
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Introduction  The aim of this study is to assess the results of retrograde flow of internal mammary artery and vein (IMA/V) as a donor vessel for free flap microvascular anastomosis (MVA). This need arises with bipedicle deep inferior epigastric perforator (DIEP) flaps, when all four zones with extra fat need to be harvested for unilateral breast reconstruction coupled with poor midline crossover of circulation naturally or because of midline scar. Large anterolateral thigh flaps for chest wall cover, with multiple perforators from separate pedicles, also need supercharging. This needs an additional source of donor vessels, antegrade IMA/V being the first one. Materials and Methods  Retrospective study of microvascular breast reconstruction using retrograde internal mammary donor vessels. Results  Out of 35 cases, 20 cases had distal IMA/V, with retrograde flow, as donor vessel for second set of arterial and venous anastomosis. In two cases, retrograde IMA/V was used for the solitary set of MVA. In remaining 13 cases, either retrograde IMA or V was utilized either as a principal or accessory donor. No flap was lost. Venous and arterial insufficiency happened in one case each, both were salvaged. Two cases developed partial necrosis, needing debridement and suturing. One case developed marginal necrosis. Only one case developed fat necrosis with superadded infection on follow-up. Conclusion  Distal end of IMA and IMV on retrograde flow is safe for MVA as an additional or sole pedicle. It is convenient to use being in the same field. It enables preservation of other including thoracodorsal pedicle and latissimus dorsi flap for use in case of a complication or recurrence.  相似文献   
46.
Cholangiocarcinoma is an adenocarcinoma that arises from the bile duct epithelium and is the second most common primary hepatobiliary cancer, after hepatocellular cancer, with approximately 2,500 cases annually in the U.S. However, cholangiocarcinoma remains a relatively rare disease, accounting for <2% of all human malignancies. Although the entire biliary tree is potentially at risk, tumors involving the biliary confluence or the right or left hepatic ducts (hilar cholangiocarcinoma) are most common and account for 40%-60% of all cases. Most patients present with advanced disease that is not amenable to surgical treatment. The median survival time for patients with intrahepatic cholangiocarcinoma without involvement of the hilum varies among centers from 18-30 months. The median survival time for patients with perihilar cholangiocarcinoma is slightly less, varying from 12-24 months. Despite the overall poor prognosis, survival after surgical treatment of hilar cholangiocarcinoma has improved during the past 10-15 years. This review highlights the imaging features of cholangiocarcinoma, with particular emphasis on the imaging techniques that can best assess tumor resectability and guide the surgeon regarding the potential extent of resection required in operable candidates.  相似文献   
47.

Purpose

To demonstrate the sensitivity of low temperature synchrotron X-ray diffractometry (SXRD) for detecting solute crystallization in frozen sodium phosphate buffer solutions. To determine the effect of annealing on solute crystallization in frozen solutions.

Materials and Methods

Sodium phosphate buffer solutions, at initial buffer concentrations ranging from 1 to 100 mM (pH 7.4) were cooled to ?50°C. The crystallization of disodium hydrogen phosphate dodecahydrate (Na2HPO4 ?12H2O) was monitored using a laboratory as well as a synchrotron source. At selected concentrations, the effect of annealing (at ?20°C) was investigated.

Results

With the laboratory source, solute crystallization, based on the appearance of one diagnostic peak with a d-spacing of 5.4 Å, was evident only when the initial buffer concentration was at least 50 mM. In contrast, using SXRD, crystallization was detected at initial buffer concentrations down to 1 mM. In addition, the use of a high-resolution 2D detector enabled the visualization of numerous diffraction rings of the crystalline solute. At both 10 and 100 mM buffer concentration, there was no increase in solute crystallization due to annealing.

Conclusion

By using synchrotron radiation, solute crystallization was detected with substantially increased sensitivity, making the technique useful for freeze-drying cycles of practical and commercial importance. Since numerous peaks of the crystalline solute appeared, the technique has potential utility in complex, multi-component systems.  相似文献   
48.
BACKGROUND: The lipophilicity of propofol has required dispersion in a soybean macroemulsion. The authors hypothesized that the anesthetic properties of propofol are preserved when reformulated as a transparent microemulsion rather than as a turbid macroemulsion and that the dose-response relation can be selectively modified by altering the microemulsion's surfactant type and concentration. METHODS: Microemulsions of propofol were formulated using purified poloxamer 188 (3%, 5%, 7%), and sodium salt of fatty acids (C(8), C(10), C(12)) in saline and characterized using ternary/binary diagrams, particle sizing, and stability upon dilution. Rats received propofol (10 mg . kg(-1) . min(-1)) as either a microemulsion or a conventional macroemulsion to determine these end points: induction (dose; stunned; loss of lash reflex, righting reflex, withdrawal to toe pinch) and recovery (recovery of lash, righting, withdrawal reflexes). After a 14-day recovery period, rats were crossed over into the opposite experimental limb. RESULTS: Forty-eight microemulsions (diameter, 11.9-47.7 nm) were formulated. Longer carbon chain length led to a marked increase in the volume of diluent necessary to break these microemulsions. All rats experienced anesthetic induction with successful recovery, although significantly greater doses of propofol were required to induce anesthesia with microemulsions irrespective of surfactant concentration or type than with macroemulsions. The sodium salt of C10 fatty acid microemulsion required the greatest dose and longest time for anesthetic induction. CONCLUSION: Propofol microemulsions cause induction in rats similar to that from macroemulsions. The surfactant concentration and type markedly affect the spontaneous destabilization and anesthetic properties of microemulsions, a phenomenon suggesting a mechanism whereby dose-response relation can be selectively modified.  相似文献   
49.

Purpose  

To evaluate the effect of CT perfusion (CTp) protocol modifications on quantitative perfusion parameters, radiation dose and data processing time.  相似文献   
50.
Flaps from temporal region have been used for mid face, orbital and peri-orbital reconstruction. The knowledge of the vascular anatomy of the region helps to dissect and harvest the muscle/fascia/skin/combined tissue flaps from that region depending upon the requirement. Suprastructure maxillectomy defects are usually covered with free flaps to fill the cavity. Here we report an innovative idea in which a patient with a supra structure maxillectomy with external skin defect was covered with chimeric flap based on the parietal and frontal branches of superficial temporal artery and the temporalis muscle flap based on deep temporal artery.KEY WORDS: Chimeric flap, orbital floor defect, suprastructure maxillectomy, superficial temporal artery  相似文献   
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