Laser speckle imaging to evaluate scalp flap blood flow during closure in neurosurgical procedures

Background: To measure the degree of relative ischemia caused by skin closure, we explored the potential utility of intraoperative surface blood flow measurement with laser speckle imaging (LSI). Methods: Prospective observational study of eight subjects that underwent intraoperative LSI during elective cranial neurosurgical procedures at the time of skin closure. Results: Seven 1st time incisions, with closure techniques including sutures (n = 3), staples (n = 3), and one after galeal sutures. When compared to the control region, there was a mean 63.7% reduction in flow across all seven subjects (range 18.7–95.32%). Comparing by closure type, a higher flow reduction in the three subjects with suture closure (80.7% reduction) compared to staples (61.9% reduction, P = 0.0379). One subject had a complex wound where tightening and loosening of sutures were performed to ensure adequate perfusion. Suturing resulted in significantly more local decreased flow compared to staples (P < 0.0001). Conclusion: These findings demonstrate the relative feasibility of using LSI for preoperative vascular flow assessment in planning complex incision closure. These data also provide preliminary support for the hypothesis that skin closure itself causes relative ischemia compared to deep approximation or cautery of the skin edge and that the relative ischemia from staples closure is generally less than from suture closure.

Graves’ Disease Following Subacute Thyroiditis

Subacute thyroiditis is an inflammatory thyroid disease caused by viral infection. Graves’ disease is an autoimmune thyroid disease caused by thyrotropin (TSH) receptor antibody (TRAb). Graves’ disease following subacute thyroiditis is rare, and only a few cases have been reported. A 58-year-old woman presented with anterior neck pain and swallowing difficulty. Laboratory tests showed elevated FT4, low TSH, normal TRAb, and elevated erythrocyte sedimentation rate. Thyroid ultrasonography (US) revealed focal, ill-defined hypoechoic areas in both thyroid lobes. The patient was treated with corticosteroid, and symptoms subsided after 1 month. Three months later, she complained of tremor and palpitation. Thyroid function testing showed hyperthyroidism with the positive conversion of TRAb, indicating Graves’ disease. Doppler US showed increased vascular flow in both thyroid lobes. She started treatment for hyperthyroidism with methimazole.

Bilateral Testicular Torsion: A Case Report

Bilateral testicular torsion is a rare condition. We report a case of a male newborn with bilateral enlarged and firm testes. Color-Doppler revealed no evidence of vascular flow in both testes. Although intraoperative findings were in favor of bilateral infarcted and gangrenous testes, the patient underwent bilateral orchiopexy after conferring with his parents. At sixmonth follow-up, both testicles were atrophic. Management of bilateral neonatal testicular torsion is controversial and includes conservative management, orchiopexy, and orchiectomy. The possibility of salvaging testis in neonatal testicular torsion is very low in each treatment modality.

Liposomal Nanocarriers Designed for Sub-Endothelial Matrix Targeting under Vascular Flow Conditions

Vascular interventions result in the disruption of the tunica intima and the exposure of sub-endothelial matrix proteins. Nanoparticles designed to bind to these exposed matrices could provide targeted drug delivery systems aimed at inhibiting dysfunctional vascular remodeling and improving intervention outcomes. Here, we present the progress in the development of targeted liposomal nanocarriers designed for preferential collagen IV binding under simulated static vascular flow conditions. PEGylated liposomes (PLPs), previously established as effective delivery systems in vascular cells types, served as non-targeting controls. Collagen-targeting liposomes (CT-PLPs) were formed by conjugating established collagen-binding peptides to modified lipid heads via click chemistry (CTL), and inserting them at varying mol% either at the time of PLP assembly or via micellar transfer. All groups included fluorescently labeled lipid species for imaging and quantification. Liposomes were exposed to collagen IV matrices statically or via hemodynamic flow, and binding was measured via fluorometric analyses. CT-PLPs formed with 5 mol% CTL at the time of assembly demonstrated the highest binding affinity to collagen IV under static conditions, while maintaining a nanoparticle characterization profile of ~50 nm size and a homogeneity polydispersity index (PDI) of ~0.2 favorable for clinical translation. When liposomes were exposed to collagen matrices within a pressurized flow system, empirically defined CT-PLPs demonstrated significant binding at shear stresses mimetic of physiological through pathological conditions in both the venous and arterial architectures. Furthermore, when human saphenous vein explants were perfused with liposomes within a closed bioreactor system, CT-PLPs demonstrated significant ex vivo binding to diseased vascular tissue. Ongoing studies aim to further develop CT-PLPs for controlled targeting in a rodent model of vascular injury. The CT-PLP nanocarriers established here show promise as the framework for a spatially controlled delivery platform for future application in targeted vascular therapeutics.

Management of Hemorrhoids with Doppler-Guided Hemorrhoidal Artery Ligation

Background An innovative therapy for symptomatic hemorrhoids has been recently proposed it relies on the reduction of hemorrhoidal vascular flow by suturing hemorrhoidal arteries, which are previously located by means of an ultrasound transducer. Objective To evaluate retrospectively the outcome of Doppler-guided hemorrhoidal artery ligation in the management of symptomatic hemorrhoids. Patients and Methods Aretrospective study. The study conducted in Ain Shams University Hosptial (El Demerdash) under supervision of these supervisors. Study period: Six months. Results In our series, the HAL technique has achieved complete control of symptoms in 93.3% of patients after six-monthes follow-up. Conclusion Hemorrhoid ligation with mucopexy is a simple, safe and cost-effective ambulatory treatment for the patients of symptomatic hemorrhoids. It can be performed on an outpatient or day care basis on all grades of hemorrhoids to control bleeding and prolapsing hemorrhoids. Overall the results of hemorrhoid ligation and mucopexy were satisfactory with good control of patients complains.

Uncontrolled bleeding during tooth extraction from an undiagnosed arteriovenous malformation

Arteriovenous malformations (AVMs) are rare congenital disorders of vascular morphogenesis. These lesions are characterised by high vascular flow with risk of severe bleeding from accidental trauma or surgical manipulation. Although infrequent, potentially life-threatening and fatal oral bleeding has been reported during extraction of tooth associated with AVM. This paper presents a case of uncontrolled bleeding in an adult female patient undergoing mandibular anterior tooth extraction. The bleeding was related to undiagnosed soft tissue AVM in gingivobuccal space. Management of the case with review of previously reported similar cases is presented.

Analysis of 3-Dimensional Arch Anatomy, Vascular Flow, and Postnatal Outcome in Cases of Suspected Coarctation of the Aorta Using Fetal Cardiac Magnetic Resonance Imaging

Background: Identifying fetuses at risk of severe neonatal coarctation of the aorta (CoA) can be lifesaving but is notoriously challenging in clinical practice with a high rate of false positives. Novel fetal 3-dimensional and phase-contrast magnetic resonance imaging (MRI) offers an unprecedented means of assessing the human fetal cardiovascular system before birth. We performed detailed MRI assessment of fetal vascular morphology and flows in a cohort of fetuses with suspected CoA, correlated with the need for postnatal intervention. Methods: Women carrying a fetus with suspected CoA on echocardiography were referred for MRI assessment between 26 and 36 weeks of gestation, including high-resolution motion-corrected 3-dimensional volumes of the fetal heart and phase-contrast flow sequences gated with metric optimized gating. The relationship between aortic geometry and vascular flows was then analyzed and compared with postnatal outcome. Results: Seventy-two patients (51 with suspected fetal CoA and 21 healthy controls) underwent fetal MRI with motion-corrected 3-dimensional vascular reconstructions. Vascular flow measurements from phase-contrast sequences were available in 53 patients. In the CoA group, 25 of 51 (49%) required surgical repair of coarctation after birth; the remaining 26 of 51 (51%) were discharged without neonatal intervention. Reduced blood flow in the fetal ascending aorta and at the aortic isthmus was associated with increasing angulation ( P =0.005) and proximal displacement ( P =0.006) of the isthmus and was seen in both true positive and false positive cases. A multivariate logistic regression model including aortic flow and isthmal displacement explained 78% of the variation in outcome and correctly predicted the need for intervention in 93% of cases. Conclusions: Reduced blood flow though the left heart is associated with important configurational changes at the aortic isthmus in fetal life, predisposing to CoA when the arterial duct closes after birth. Novel fetal MRI techniques may have a role in both understanding and accurately predicting severe neonatal CoA.

Red Blood Cells: Tethering, Vesiculation, and Disease in Micro-Vascular Flow

The red blood cell has become implicated in the progression of a range of diseases; mechanisms by which red cells are involved appear to include the transport of inflammatory species via red cell-derived vesicles. We review this role of RBCs in diseases such as diabetes mellitus, sickle cell anemia, polycythemia vera, central retinal vein occlusion, Gaucher disease, atherosclerosis, and myeloproliferative neoplasms. We propose a possibly unifying, and novel, paradigm for the inducement of RBC vesiculation during vascular flow of red cells adhered to the vascular endothelium as well as to the red pulp of the spleen. Indeed, we review the evidence for this hypothesis that links physiological conditions favoring both vesiculation and enhanced RBC adhesion and demonstrate the veracity of this hypothesis by way of a specific example occurring in splenic flow which we argue has various renderings in a wide range of vascular flows, in particular microvascular flows. We provide a mechanistic basis for membrane loss and the formation of lysed red blood cells in the spleen that may mediate their turnover. Our detailed explanation for this example also makes clear what features of red cell deformability are involved in the vesiculation process and hence require quantification and a new form of quantitative indexing.

Integrated transcriptomic and neuroimaging brain model decodes biological mechanisms in aging and Alzheimer’s disease

Both healthy aging and Alzheimer’s disease (AD) are characterized by concurrent alterations in several biological factors. However, generative brain models of aging and AD are limited in incorporating the measures of these biological factors at different spatial resolutions. Here, we propose a personalized bottom-up spatiotemporal brain model that accounts for the direct interplay between hundreds of RNA transcripts and multiple macroscopic neuroimaging modalities (PET, MRI). In normal elderly and AD participants, the model identifies top genes modulating tau and amyloid-β burdens, vascular flow, glucose metabolism, functional activity, and atrophy to drive cognitive decline. The results also revealed that AD and healthy aging share specific biological mechanisms, even though AD is a separate entity with considerably more altered pathways. Overall, this personalized model offers novel insights into the multiscale alterations in the elderly brain, with important implications for identifying effective genetic targets for extending healthy aging and treating AD progression.