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Cardiovascular Diagnosis and Therapy Oct 2021Nutcracker syndrome (NCS) is an extrinsic compression of the left renal vein (LRV) by the superior mesenteric artery (SMA) anteriorly and aorta posteriorly resulting in... (Review)
Review
Nutcracker syndrome (NCS) is an extrinsic compression of the left renal vein (LRV) by the superior mesenteric artery (SMA) anteriorly and aorta posteriorly resulting in renal vascular congestion manifesting as hematuria, proteinuria, orthostatic hypotension, pain, or even renal dysfunction. Long-standing venous compression can encourage collateral drainage pathways through gonadal and pelvic veins, which may explain reported symptom and syndrome overlap with pelvic congestion syndrome. Diagnosis can be challenging and variable, frequently involving a combination of ultrasound Doppler, cross-sectional, and invasive imaging. Often, intravascular pressure measurements are required to prove a renocaval pressure gradient to aid in a definitive diagnosis. Conservative management is appropriate, especially in children, who tend to outgrow the disorder. In the interim, medical management with angiotensin converting enzyme inhibitors (ACEIs) is a useful therapy to manage orthostatic hypotension in the pediatric population. In adults, invasive therapies are more frequently pursued. These are aimed at relieving the extrinsic compression on the LRV. The standard of care is renal vein transposition, with renal autotransplantation reserved for recalcitrant cases. Endovascular stenting is a less invasive option. Laparoscopic placement of an exovascular stent is a newer therapy intended to minimize trauma to the LRV. In this review, we will discuss the clinical manifestations, diagnostic criterion, imaging features, and conservative and surgical therapies for this condition.
PubMed: 34815965
DOI: 10.21037/cdt-20-160 -
European Urology Dec 2015A detailed understanding of renal surgical anatomy is necessary to optimize preoperative planning and operative technique and provide a basis for improved outcomes. (Review)
Review
CONTEXT
A detailed understanding of renal surgical anatomy is necessary to optimize preoperative planning and operative technique and provide a basis for improved outcomes.
OBJECTIVE
To evaluate the literature regarding pertinent surgical anatomy of the kidney and related structures, nephrometry scoring systems, and current surgical strategies for partial nephrectomy (PN).
EVIDENCE ACQUISITION
A literature review was conducted.
EVIDENCE SYNTHESIS
Surgical renal anatomy fundamentally impacts PN surgery. The renal artery divides into anterior and posterior divisions, from which approximately five segmental terminal arteries originate. The renal veins are not terminal. Variations in the vascular and lymphatic channels are common; thus, concurrent lymphadenectomy is not routinely indicated during PN for cT1 renal masses in the setting of clinically negative lymph nodes. Renal-protocol contrast-enhanced computed tomography or magnetic resonance imaging is used for standard imaging. Anatomy-based nephrometry scoring systems allow standardized academic reporting of tumor characteristics and predict PN outcomes (complications, remnant function, possibly histology). Anatomy-based novel surgical approaches may reduce ischemic time during PN; these include early unclamping, segmental clamping, tumor-specific clamping (zero ischemia), and unclamped PN. Cancer cure after PN relies on complete resection, which can be achieved by thin margins. Post-PN renal function is impacted by kidney quality, remnant quantity, and ischemia type and duration.
CONCLUSIONS
Surgical renal anatomy underpins imaging, nephrometry scoring systems, and vascular control techniques that reduce global renal ischemia and may impact post-PN function. A contemporary ideal PN excises the tumor with a thin negative margin, delicately secures the tumor bed to maximize vascularized remnant parenchyma, and minimizes global ischemia to the renal remnant with minimal complications.
PATIENT SUMMARY
In this report we review renal surgical anatomy. Renal mass imaging allows detailed delineation of the anatomy and vasculature and permits nephrometry scoring, and thus precise, patient-specific surgical planning. Novel off-clamp techniques have been developed that may lead to improved outcomes.
Topics: Humans; Kidney; Nephrectomy
PubMed: 25911061
DOI: 10.1016/j.eururo.2015.04.010 -
Blood Advances Nov 2018Despite an increasing incidence of venous thromboembolism (VTE) in pediatric patients in tertiary care settings, relatively few pediatric physicians have experience with...
BACKGROUND
Despite an increasing incidence of venous thromboembolism (VTE) in pediatric patients in tertiary care settings, relatively few pediatric physicians have experience with antithrombotic interventions.
OBJECTIVE
These guidelines of the American Society of Hematology (ASH), based on the best available evidence, are intended to support patients, clinicians, and other health care professionals in their decisions about management of pediatric VTE.
METHODS
ASH formed a multidisciplinary guideline panel that included 2 patient representatives and was balanced to minimize potential bias from conflicts of interest. The McMaster University GRADE Centre supported the guideline-development process, including updating or performing systematic evidence reviews (up to April of 2017). The panel prioritized clinical questions and outcomes according to their importance for clinicians and patients. The panel used the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach, including GRADE Evidence-to-Decision frameworks, to assess evidence and make recommendations, which were subject to public comment.
RESULTS
The panel agreed on 30 recommendations, covering symptomatic and asymptomatic deep vein thrombosis, with specific focus on management of central venous access device-associated VTE. The panel also addressed renal and portal vein thrombosis, cerebral sino venous thrombosis, and homozygous protein C deficiency.
CONCLUSIONS
Although the panel offered many recommendations, additional research is required. Priorities include understanding the natural history of asymptomatic thrombosis, determining subgroup boundaries that enable risk stratification of children for escalation of treatment, and appropriate study of newer anticoagulant agents in children.
Topics: Anticoagulants; Antithrombins; Central Venous Catheters; Child; Evidence-Based Medicine; Humans; Portal Vein; Pulmonary Embolism; Purpura Fulminans; Renal Veins; Risk Factors; Venous Thromboembolism; Venous Thrombosis
PubMed: 30482766
DOI: 10.1182/bloodadvances.2018024786 -
Experimental and Clinical... Apr 2017Transplant renal vein thrombosis usually occurs early after surgery with a reported prevalence of 0.1% to 4.2%. It is a devastating event that ultimately leads to graft... (Review)
Review
Transplant renal vein thrombosis usually occurs early after surgery with a reported prevalence of 0.1% to 4.2%. It is a devastating event that ultimately leads to graft loss in almost all cases. There are many predisposing factors related to donor, recipient, surgery, and immunosuppression, with mechanical factors being considered the most common causes of transplant renal vein thrombosis. The clinical manifestations of acute renal vein thrombosis are nonspecific and are not dissimilar to the features of urine leak, urinary obstruction, or severe acute rejection. The diagnosis of transplant renal vein thrombosis depends on a high index of clinical suspicion and duplex ultrasonographic scans. Although venography remains the criterion standard, this procedure is invasive and nephrotoxic, due to use of ionizing contrast agents and also due to exposure to ionizing radiation. There are 2 therapies that have been described in the literature for salvaging a renal allograft with transplant renal vein thrombosis: thrombolytic therapy and surgical thrombectomy. The usual end result is renal allograft.
Topics: Allografts; Humans; Immunosuppressive Agents; Kidney Transplantation; Magnetic Resonance Angiography; Nephrectomy; Predictive Value of Tests; Prevalence; Renal Veins; Risk Factors; Thrombectomy; Thrombolytic Therapy; Time Factors; Treatment Outcome; Ultrasonography, Doppler, Duplex; Venous Thrombosis
PubMed: 28338457
DOI: 10.6002/ect.2016.0060 -
Medicina 2019Nutcracker syndrome is a vascular anomaly consisting in the compression of the left renal vein between the superior mesenteric artery and the aorta. Clinical features in...
Nutcracker syndrome is a vascular anomaly consisting in the compression of the left renal vein between the superior mesenteric artery and the aorta. Clinical features in nutcracker syndrome include pelvic pain, flank pain, haematuria, gonadal varices or simply asymptomatic. We are presenting two cases, one of them with macroscopic haematuria and flank pain and the other was studied for hypertension but with previous antecedents of left renal vein embolization in the setting of varicocele. We discuss the clinical presentation as well as diagnostic and therapeutic aspects related to this syndrome.
Topics: Adolescent; Adult; Computed Tomography Angiography; Female; Hematuria; Humans; Renal Nutcracker Syndrome; Renal Veins
PubMed: 31048282
DOI: No ID Found -
Cancers Nov 2023Cancer is associated with an increased risk of developing venous thromboembolism, due to its direct influence on the three pillars of Virchow's triad (e.g., compression... (Review)
Review
Cancer is associated with an increased risk of developing venous thromboembolism, due to its direct influence on the three pillars of Virchow's triad (e.g., compression on the blood vessels by the tumour, blood vessels invasion, and cytokine release), together with the effect of exogenous factors (such as chemotherapy, radiotherapy, surgery). In cancer patients, the risk of thrombosis at unusual sites, such as splanchnic, ovarian and renal vein thrombosis, is also increased. Abdominal vein thromboses are frequently incidental findings on abdominal imaging performed as part of the diagnostic/staging workup or the follow-up care of malignancies. There is little evidence on the management of unusual site venous thromboembolism in cancer patients since there are only a few specific recommendations; thus, the management follows the general principles of the treatment of cancer-associated deep vein thrombosis and pulmonary embolism. This narrative review summarises the latest evidence on cancer-associated abdominal vein thrombosis, i.e., thrombosis of the splanchnic, ovarian and renal veins.
PubMed: 37958466
DOI: 10.3390/cancers15215293 -
Journal of Radiology Case Reports May 2022Nutcracker syndrome (NCS) is a rare condition caused by the compression of the left renal vein between the abdominal aorta and the superior mesenteric artery. NCS may...
Nutcracker syndrome (NCS) is a rare condition caused by the compression of the left renal vein between the abdominal aorta and the superior mesenteric artery. NCS may present with unexplained hematuria. This case report presents a 43-year-old healthy female without any complaints who had newly-detected hematuria in urinalysis during her annual examination. Her physical examination and the whole abdominal ultrasonography failed to explain the cause of hematuria. Further investigation with contrast-enhanced upper abdominal computed tomography revealed a NCS. In unexplained cases of asymptomatic hematuria NCS should be taken into account after excluding other preliminary diagnoses.
Topics: Adult; Female; Hematuria; Humans; Mesenteric Artery, Superior; Renal Veins; Syndrome; Tomography, X-Ray Computed
PubMed: 35711687
DOI: 10.3941/jrcr.v16i5.4339 -
Seminars in Cell & Developmental Biology Jul 2019The kidney vasculature has a unique and complex architecture that is central for the kidney to exert its multiple and essential physiological functions with the ultimate... (Review)
Review
The kidney vasculature has a unique and complex architecture that is central for the kidney to exert its multiple and essential physiological functions with the ultimate goal of maintaining homeostasis. An appropriate development and coordinated assembly of the different vascular cell types and their association with the corresponding nephrons is crucial for the generation of a functioning kidney. In this review we provide an overview of the renal vascular anatomy, histology, and current knowledge of the embryological origin and molecular pathways involved in its development. Understanding the cellular and molecular mechanisms involved in renal vascular development is the first step to advance the field of regenerative medicine.
Topics: Animals; Gene Expression Regulation, Developmental; Humans; Kidney; Neovascularization, Physiologic; Nephrons; Regenerative Medicine; Renal Artery; Renal Veins
PubMed: 29879472
DOI: 10.1016/j.semcdb.2018.06.001