Treatment of cold intolerance following finger pulp amputations: a case comparison between immediate finger replantation and delayed pulp and digital arterial arch reconstruction with flow-through free hypothenar flap

Study of flow through arteries is gaining importance in the recent times due to onset of several cardio-vascular diseases like atherosclerosis (block in artery), aneurysms (bulging of artery), hypertension etc. The application of CFD will be useful in demonstrating the underlying mechanism of flow past the diseased arteries. In the present study, initially an approximate eccentric and concentric 50% stenosed carotid model is generated in ANSYS 12.0 based on patient data obtained from ultrasound Doppler scan. Later the percentage of stenosis is increased to 60%, 70%, 80% and 90% in both the cases. A transient analysis has been performed for several pulse cycles in ANSYS FLOTRAN for various percentage cases. The results obtained from ECN and CCN cases are compared to observe the changes in flow behavior in the downstream of stenosis as compared with normal case. The formation of vortices and flow separation zone in downstream in eccentric case is higher than in concentric case. Comparison of results concludes that, with the increase in severity of stenosis, the flow changes abruptly causing an increase in velocity and WSS at throat region. The simulation results obtained agree well with clinically observed data and available literature.

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The Dorsal Middle Phalangeal Finger Flap

Journal of Hand Surgery (European Volume) ◽

10.1016/s0266-7681(97)80403-2 ◽

1997 ◽

Vol 22 (3) ◽

pp. 362-371 ◽

Cited By ~ 25

Author(s):

P. LEUPIN ◽

J. WEIL ◽

U. BÜCHLER

Keyword(s):

Digital Artery ◽

Digital Nerve ◽

Venous Flow ◽

Cold Intolerance ◽

Dorsal Vein ◽

Neurovascular Flap ◽

Dorsal Branch ◽

Flow Through ◽

A Prospective Study

The dorsal middle phalangeal finger (DMF) flap is a (neuro)vaseular island flap based on one palmar proper digital artery, its venae comitantes (and/or a separate dorsal vein) and the dorsal branch(es) of the palmar digital nerve. The main nerve supply of the donor finger is left undisturbed. The flap may be raised on a short antegrade, long antegrade or a retrograde pedicle, and used as a free, arterial and/or venous flow-through or neurovascular flap. In a prospective study (mean follow-up of 50 months), the results of 43 DMF flaps were analysed. All flaps survived, retained patency of their vascular pedicles and fulfilled their goals. Neurovascular flaps provided sensate coverage at the S3+ level with static 2-point discrimination values of about 10 mm. Dissection between the proper digital nerve and the rest of the neurovascular bundle induced a 5% incidence of cold intolerance and a 12% occurrence of S3+ hypaesthesia. Advantages, drawbacks and indications of DMF flaps are outlined.

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Development of apical pits in chloride cells of the gills of Pimephales promelas after chronic exposure to acid water

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100076044 ◽

1983 ◽

Vol 41 ◽

pp. 462-463

Author(s):

Richard L. Leino ◽

Jon G. Anderson ◽

J. Howard McCormick

Keyword(s):

Confidence Interval ◽

Chronic Exposure ◽

Lake Superior ◽

Pimephales Promelas ◽

Chloride Cells ◽

Fathead Minnows ◽

Secondary Lamellae ◽

Untreated Water ◽

Water Ph ◽

Flow Through

Groups of 12 fathead minnows were exposed for 129 days to Lake Superior water acidified (pH 5.0, 5.5, 6.0 or 6.5) with reagent grade H2SO4 by means of a multichannel toxicant system for flow-through bioassays. Untreated water (pH 7.5) had the following properties: hardness 45.3 ± 0.3 (95% confidence interval) mg/1 as CaCO3; alkalinity 42.6 ± 0.2 mg/1; Cl- 0.03 meq/1; Na+ 0.05 meq/1; K+ 0.01 meq/1; Ca2+ 0.68 meq/1; Mg2+ 0.26 meq/1; dissolved O2 5.8 ± 0.3 mg/1; free CO2 3.2 ± 0.4 mg/1; T= 24.3 ± 0.1°C. The 1st, 2nd and 3rd gills were subsequently processed for LM (methacrylate), TEM and SEM respectively.Three changes involving chloride cells were correlated with increasing acidity: 1) the appearance of apical pits (figs. 2,5 as compared to figs. 1, 3,4) in chloride cells (about 22% of the chloride cells had pits at pH 5.0); 2) increases in their numbers and 3) increases in the % of these cells in the epithelium of the secondary lamellae.

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