Appendix-preserving elective herniorrhaphy for de Garengeot hernia: two case reports

Background Emergency appendectomy is often performed for de Garengeot hernia. However, in some cases, there may be a chance to perform an appendix-preserving elective surgery. Case description A 76-year-old woman presented to our hospital with complaints of a right inguinal swelling, which we diagnosed as a de Garengeot hernia using computed tomography (CT). B-mode ultrasonography (US) of the mass showed an appendix 4–6 mm in diameter with a clear wall structure; color Doppler US showed pulsatile blood flow signal in the appendiceal wall. Twenty-eight days later, herniorrhaphy with transabdominal preperitoneal repair (TAPP) was performed without appendectomy. Another 70-year-old woman presented to our hospital with complaints of a painful bulge in the right inguinal region. The diagnosis of de Garengeot hernia was made using CT. B-mode US showed an appendix 5 mm in diameter with a clear wall structure. Color Doppler US showed a pulsatile blood signal in the appendiceal wall. Seven days later, herniorrhaphy with TAPP was performed without appendectomy. Conclusion De Garengeot hernia is often associated with appendicitis; however, an appendix-preserving elective herniorrhaphy can be performed if US and intraoperative findings do not suggest appendicitis or circulatory compromise in the appendix.

Monitoring free flaps and replanted digits via perfusion index –A proof of concept study

BACKGROUND: Early detection and treatment of vascular complications in replanted digits is essential for the survival. The perfusion index (PI) represents a marker of peripheral perfusion as it shows the ratio of pulsatile to non-pulsatile blood flow. OBJECTIVE: To evaluate the feasibility and applicability of the PI as a monitoring tool for free flaps and replanted digits by measuring the inter- and intraindividual changes in PI. METHODS: Five patients were postoperatively monitored according to intern standards by hourly clinical evaluation. Additionally, a pulse oximeter with SET-technology® (Masimo Radial 7, Masimo Corporation, Irvine, USA) was added with a LNCS® Red TFA-1 SpO2 sensor (Masimo Corporation, Irvine, USA) and respectively a LNCS® Neo-3 neonatal finger clip to evaluate the perfusion via PI and SpO2. RESULTS: All patients showed sufficient perfusion in clinical controls. There was no detectable vascular complication during follow-up. Mean perfusion index was 0.93 with a median of 0.44. The patients showed a mean SpO2 of 90.59%with a median of 89.21%. CONCLUSION: Our results show a great intra- and interindividual range of PI and SpO2. SpO2 provided an even greater range than PI. Trends in intraindividual PI changes may be a promising monitoring tool for free flaps and replanted digits.

A Nitric Oxide–Modulated Variable-Order Fractional Maxwell Viscoelastic Model of Cerebral Vascular Walls

It is well known that the mechanical behavior of arterial walls plays an important role in the pathogenesis of vascular diseases. Most studies existing in the literature focus on the mechanical interactions between the blood flow and wall’s deformations. However, in the brain, the smaller vessels experience not only oscillatory forces due to the pulsatile blood flow but also structural and morphological changes controlled by the surrounding brain cells. In this study, the mechanical deformation of the cerebral arterial wall caused by the pulsatile blood flow and the dynamics of the neuronal nitric oxide (NO) is investigated. NO is a small diffusive gaseous molecule produced by the endothelial cells and neurons, which is involved in the regulation of cerebral blood flow and pressure. The cerebral vessel is assumed to be a hollow axial symmetric cylinder whose wall thickness is much smaller than the cylinder’s radius and longitudinal length is much less than the propagating wavelength. The wall is an isotropic, homogeneous linear viscoelastic material described by an NO-modulated variable-order fractional Maxwell model. A fractional telegraph equation is obtained for the axial component of the displacement. Patterns of wall’s deformation are investigated through numerical simulations. The results suggest that a significantly decreased inactivation of the neuronal NO may cause a reduction in the shear stress at the blood-vessel interface, which could lead to a decrease in the production of shear-induced endothelial NO and neurovascular disease.

A Hydromechanical Perspective to Study the Effect of Body Acceleration through Stenosed Artery

The spread of numerous deadly diseases such as Thrombosis, Diabetes, Atherosclerosis and other cardiac diseases, carry on to be major root of demise and growing public curiosity about the prevention and treatment of such fatal disorders. Body acceleration has very important role on the flow through stenosed artery. In this research work a problem for irregular development in the inner wall of the artery is known atherosclerosis that settled as a result of buildup due to cholesterol on the arterial wall has been discussed. In this work the effects of body acceleration, slip velocity in presence of catheter on the wall shear, velocity profile and flow rate reveal the graphical finding for pulsatile blood flow in narrow blood vessels. Here it is shown that flow rate, velocity and shear stress escalate as body acceleration increases.

In vitro investigation of the impact of pulsatile blood flow on the vascular architecture of decellularized porcine kidneys

A method was established using a scaffold-bioreactor system to examine the impact pulsatile blood flow has on the decellularized porcine kidney vascular architecture and functionality. These scaffolds were subjected to continuous arterial perfusion of whole blood at normal physiological (650 ml/min and 500 ml/min) and pathophysiological (200 ml/min) rates to examine dynamic changes in venous outflow and micro-/macrovascular structure and patency. Scaffolds subjected to normal arterial perfusion rates observed drops in venous outflow over 24 h. These reductions rose from roughly 40% after 12 h to 60% after 24 h. There were no apparent signs of clotting at the renal artery, renal vein, and ureter. In comparison, venous flow rates decreased by 80% to 100% across the 24 h in acellular scaffolds hypoperfused at a rate of 200 ml/min. These kidneys also appeared intact on the surface after perfusion. However, they presented several arterial, venous, and ureteral clots. Fluoroscopic angiography confirmed substantial alterations to normal arterial branching patterns and patency, as well as parenchymal damage. Scanning electron microscopy revealed that pulsatile blood perfusion significantly disrupted glomerular microarchitecture. This study provides new insight into circumstances that limit scaffold viability and a simplified model to analyze conditions needed to prepare more durable scaffolds for long-term transplantation.

Pulsation of anastomotic vortex veins in pachychoroid spectrum diseases

Accumulating evidence points to pachychoroid possibly being caused by vortex vein congestion which results in remodeling of choroidal drainage routes via intervortex vein anastomosis. This hypothesis prompted us to investigate vortex vein hemodynamics by studying videos of indocyanine green angiography (ICGA) in a retrospective case series of 295 eyes with pachychoroid spectrum diseases. In the early phase of the video-ICGA, pulsatile vortex venous flow was observed in 76 eyes (25.8%) at the vortex veins connected with anastomosis between superior and inferior vortex veins. The patients with pulsatile vortex venous flow were significantly older than those without pulsatile vortex venous flow (67.8 ± 13.2 vs. 63.9 ± 14.5 years, P < 0.05). Pulsatile vortex venous flow was 1.84 times more common in the inferior quadrants than in the superior quadrants. Interestingly, 14 of 76 eyes (18.4%) with pulsatile vortex venous flow showed retrograde pulsatile blood flow in the vortex veins. This retrograde pulsatile blood flow was 2.50 times more common in the inferior than in the superior quadrants. These findings indicate altered vortex vein hemodynamics due to vortex vein congestion in pachychoroid spectrum diseases.