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Journal of Neurointerventional Surgery Aug 2023Collateral circulation is an important determinant of outcome in people with acute ischemic stroke due to large vessel occlusion (LVO).
BACKGROUND
Collateral circulation is an important determinant of outcome in people with acute ischemic stroke due to large vessel occlusion (LVO).
OBJECTIVE
To explore the impact of the circle of Willis (CW) anatomical characteristics ipsilateral to the occlusion site, particularly the posterior communicating artery (PComA) and the A1-portion of the anterior cerebral artery (A1-ACA), on stroke outcomes in a cohort of patients with LVO and middle cerebral artery (MCA) occlusion, undergoing endovascular thrombectomy (EVT).
METHODS
This is a retrospective cohort study performed in a comprehensive tertiary stroke center. The study population consisted of consecutive patients with LVO with proximal MCA occlusion (M1) between June 2016 and April 2021, undergoing EVT. Demographic, clinical, and imaging information was extracted from patient files. Patency and diameters of ipsilateral A1-ACA and PComA were manually measured on admission CT angiography images in the core laboratory.
RESULTS
One hundred and five patients with LVO comprised the study cohort, mean age 72.3 years, 43.8% were male, mean National Institutes of Health Stroke Scale score at admission 15.2. The cohort was grouped according to CW vessel characteristics. On univariate analysis, a well-developed PComA was associated with lower rates of hemorrhagic transformation (1.8% vs 14.3%, P=0.01) and a trend towards lower mortality rates (8.9% vs 20.4%, P=0.08).On multivariable regression analysis a well-developed PComA emerged as an independent predictor for survival (aOR=0.09, 95% CI 0.01 to 0.4 for survival at discharge, P=0.009, aOR=0.22, 95% CI 0.05 to 0.8 for survival at 90 days, P=0.02).
CONCLUSIONS
In a cohort of patients with LVO due to M1 occlusion undergoing EVT, a well-developed PComA was associated with significantly lower hemorrhagic transformation rates, a trend towards better functional outcomes, and independently predicted survival. Larger studies are needed to understand the differential effect of CW collateral conduits on stroke outcome and evaluate the practicality of incorporating such factors in the clinical decision-making process prior to EVT.
PubMed: 37527929
DOI: 10.1136/jnis-2023-020326 -
Rhode Island Medical Journal (2013) Aug 2023Urinary diversion in renal transplant patients can take a variety of forms - bladder augmentation, continent cutaneous pouch, or intestinal conduits, to name a few....
Urinary diversion in renal transplant patients can take a variety of forms - bladder augmentation, continent cutaneous pouch, or intestinal conduits, to name a few. Herein, we present a unique case of an appendicocecal urinary diversion in a patient with history of end stage renal disease, pelvic radiation, and complex surgical history who underwent deceased-donor renal transplantation. During the renal transplant, the transplant ureterovesical anastomosis could not be performed due to inherent anatomical hindrances. A temporary modified cutaneous ureterostomy using a single-J stent was therefore used for drainage of the transplant kidney. Given that the cutaneous ureterostomy was not a durable, long-term option, we sought to develop a creative surgical solution. This report presents a unique case of urinary diversion post renal transplant and reviews the literature of renal transplantation in patients with anatomical abnormalities.
Topics: Humans; Urinary Diversion; Kidney; Ureterostomy; Ureter; Kidney Transplantation
PubMed: 37494618
DOI: No ID Found -
Tomography (Ann Arbor, Mich.) Jun 2023The skull base provides a platform for supporting the brain while serving as a conduit for major neurovascular structures. In addition to malignant lesions originating... (Review)
Review
The skull base provides a platform for supporting the brain while serving as a conduit for major neurovascular structures. In addition to malignant lesions originating in the skull base, there are many benign entities and developmental variants that may simulate disease. Therefore, a basic understanding of the relevant embryology is essential. Lesions centered in the skull base can extend to the adjacent intracranial and extracranial compartments; conversely, the skull base can be secondarily involved by primary extracranial and intracranial disease. CT and MRI are the mainstay imaging methods and are complementary in the evaluation of skull base lesions. Advances in cross-sectional imaging have been crucial in the management of patients with skull base pathology, as this represents a complex anatomical area that is hidden from direct clinical exam. Furthermore, the clinician must rely on imaging studies for therapy planning and to monitor treatment response. It is crucial to have a thorough understanding of skull base anatomy and its various pathologies, as well as to recognize the appearance of treatment-related changes. In this review, we aim to describe skull base tumors and tumor-like lesions in an anatomical compartmental approach and present imaging methods that aid in diagnosis, management, and follow-up.
Topics: Humans; Skull Base Neoplasms; Diagnostic Imaging; Brain
PubMed: 37489465
DOI: 10.3390/tomography9040097 -
Journal of Vascular Surgery Nov 2023The purpose of this study is obtain robust objective data from the Vascular Quality Initiative on physician work in infrainguinal artery bypass surgery. Operative time,...
OBJECTIVE
The purpose of this study is obtain robust objective data from the Vascular Quality Initiative on physician work in infrainguinal artery bypass surgery. Operative time, patient comorbidities, anatomical complexity, consequences of adverse outcomes, and postoperative length of stay all factor into procedure relative value unit assignment and physician reimbursement.
METHODS
Baseline demographics and comorbidities were identified among 74,920 infrainguinal bypass surgeries in Vascular Quality Initiative between 2003 and 2022. Investigation into areas of progressive complexity over time was conducted. Bypasses were divided into 10 cohorts based on inflow and target arteries and conduit type. Mean operative times, lengths of stay, major morbidity rates, and 90-day mortality rates were identified across the various bypasses. Comparison of relative value unit per minute service time during the acute inpatient hospital admission was performed between the most 4 common bypasses and 14 commonly performed highly invasive major surgeries across several subdisciplines.
RESULTS
Patients undergoing infrainguinal arterial bypass have an advanced combination of medical complexities highlighted by diabetes mellitus in 40%, hypertension in 88%, body mass index >30 in 30%, coronary artery disease that has clinically manifested in 31%, renal insufficiency in 19%, chronic obstructive pulmonary disease in 27%, and prior lower extremity arterial intervention (endovascular and open combined) in >50%. The need for concomitant endarterectomy at the proximal anastomosis site of infrainguinal bypasses has increased over time (P < .001). The indication for bypass being limb-threatening ischemia as defined by ischemic rest pain, pedal tissue loss, or acute ischemia has also increased over time (P < .001), indicating more advanced extent of arterial occlusion in patients undergoing infrainguinal bypass. Finally, there has been a significant (P < .001) progression in the percentage of patients who have undergone a prior ipsilateral lower extremity endovascular intervention at the time of their bypass (increasing from 9.9% in 2003-2010 to 31.9% in the 2018-2022 eras). Among the 18 procedures investigated, the 4 most commonly performed infrainguinal bypasses were included in the analysis. These ranked 14th, 16th, 17th and 18th as the most poorly compensated per minute service time during the acute operative inpatient stay.
CONCLUSIONS
Infrainguinal arterial bypass surgery has an objectively undervalued physician work relative value unit compared with other highly invasive major surgeries across several subdisciplines. There are elements of progressive complexity in infrainguinal bypass patients over the past 20 years among a patient cohort with a very high comorbidity rate, indicating escalating intensity for infrainguinal bypass.
PubMed: 37482140
DOI: 10.1016/j.jvs.2023.07.009 -
The Pan African Medical Journal 2023Type A aortic dissection (TAAD) is associated with high mortality in the absence of appropriate surgical therapy. The involvement of the aortic root by the intimal tear...
Type A aortic dissection (TAAD) is associated with high mortality in the absence of appropriate surgical therapy. The involvement of the aortic root by the intimal tear and the presence of severe aortic insufficiency will require a more radical approach with composite root replacement (CRR) in most of the patients. We briefly report our surgical experience following CRR in 12 patients presenting with TAAD in our department. Between November 2009 and January 2022, a total of twelve (n=12) patients diagnosed with TAAD were operated in our institution. Clinical data and surgical outcomes were retrospectively reviewed. The mean age at admission was 51.1 ± 12.43 years (range: 34-72). One patient met the criteria for Marfan´s disease (1/12, 8.3%). The operative mortality was 16.66% (2/12). Composite root replacement with a mechanical valved conduit was performed in the majority (11/12, 91.66%;) whereas a separated supracoronary graft replacement and aortic valve replacement were performed in one patient. Concomitant aortic arch surgery (hemi or total) was done in 9/12 patients (75%). The commonest postoperative complications were: chest re-exploration for bleeding in 2/12 (16.66%), transitory cerebral ischemia in 1/12 (8.33%) and low cardiac output syndrome in 2/12 (16.66%). The mean length of stay in the Intensive Care Unit (ICU) was 4.8±3.8 days (range: 2-17). Delayed referral of patients with TAAD was observed in the majority of patients as they were operated in the subacute or chronic phase. Composite root replacement in these patients is associated with acceptable outcomes despite complex anatomic-pathological lesions.
Topics: Humans; Adult; Middle Aged; Aged; Aortic Valve; Retrospective Studies; Aortic Dissection; Aorta; Blood Vessel Prosthesis Implantation; Treatment Outcome
PubMed: 37426463
DOI: 10.11604/pamj.2023.45.18.37147 -
Frontiers in Plant Science 2023Vessel traits are key in understanding trees' hydraulic efficiency, and related characteristics like growth performance and drought tolerance. While most plant hydraulic...
Vessel traits are key in understanding trees' hydraulic efficiency, and related characteristics like growth performance and drought tolerance. While most plant hydraulic studies have focused on aboveground organs, our understanding of root hydraulic functioning and trait coordination across organs remains limited. Furthermore, studies from seasonally dry (sub-)tropical ecosystems and mountain forests are virtually lacking and uncertainties remain regarding potentially different hydraulic strategies of plants differing in leaf habit. Here, we compared wood anatomical traits and specific hydraulic conductivities between coarse roots and small branches of five drought-deciduous and eight evergreen angiosperm tree species in a seasonally dry subtropical Afromontane forest in Ethiopia. We hypothesized that largest vessels and highest hydraulic conductivities are found in roots, with greater vessel tapering between roots and equally-sized branches in evergreen angiosperms due to their drought-tolerating strategy. We further hypothesized that the hydraulic efficiencies of root and branches cannot be predicted from wood density, but that wood densities across organs are generally related. Root-to-branch ratios of conduit diameters varied between 0.8 and 2.8, indicating considerable differences in tapering from coarse roots to small branches. While deciduous trees showed larger branch xylem vessels compared to evergreen angiosperms, root-to-branch ratios were highly variable within both leaf habit types, and evergreen species did not show a more pronounced degree of tapering. Empirically determined hydraulic conductivity and corresponding root-to-branch ratios were similar between both leaf habit types. Wood density of angiosperm roots was negatively related to hydraulic efficiency and vessel dimensions; weaker relationships were found in branches. Wood density of small branches was neither related to stem nor coarse root wood densities. We conclude that in seasonally dry subtropical forests, similar-sized coarse roots hold larger xylem vessels than small branches, but the degree of tapering from roots to branches is highly variable. Our results indicate that leaf habit does not necessarily influence the relationship between coarse root and branch hydraulic traits. However, larger conduits in branches and a low carbon investment in less dense wood may be a prerequisite for high growth rates of drought-deciduous trees during their shortened growing season. The correlation of stem and root wood densities with root hydraulic traits but not branch wood points toward large trade-offs in branch xylem towards mechanical properties.
PubMed: 37377798
DOI: 10.3389/fpls.2023.1127292 -
Journal of Experimental Botany Sep 2023The size-related xylem adjustments required to maintain a constant leaf-specific sapwood conductance (KLEAF) with increasing height (H) are still under discussion....
The size-related xylem adjustments required to maintain a constant leaf-specific sapwood conductance (KLEAF) with increasing height (H) are still under discussion. Alternative hypotheses are that: (i) the conduit hydraulic diameter (Dh) at any position in the stem and/or (ii) the number of sapwood rings at stem base (NSWr) increase with H. In addition, (iii) reduced stem elongation (ΔH) increases the tip-to-base conductance through inner xylem rings, thus possibly the NSWr contributing to KLEAF. A detailed stem analysis showed that Dh increased with the distance from the ring apex (DCA) in all rings of a Picea abies and a Fagus sylvatica tree. Net of DCA effect, Dh did not increase with H. Using sapwood traits from a global dataset, NSWr increased with H, decreased with ΔH, and the mean sapwood ring width (SWrw) increased with ΔH. A numerical model based on anatomical patterns predicted the effects of H and ΔH on the conductance of inner xylem rings. Our results suggest that the sapwood/heartwood transition depends on both H and ΔH, and is set when the carbon allocation to maintenance respiration of living cells in inner sapwood rings produces a lower gain in total conductance than investing the same carbon in new vascular conduits.
Topics: Trees; Xylem; Plant Leaves; Water
PubMed: 37352139
DOI: 10.1093/jxb/erad227