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Nutcracker syndrome can be diagnosed with:
- Left renal venography—considered to be the gold standard test.
- Computed tomography (CT).
- Abdominal ultrasonography—not definitive but has been found to be useful.
This is based on MRI scan, magnetic resonance angiography and CT scan. A cerebral digital subtraction angiography (DSA) enhances visualization of the fistula.
- CT scans classically show an enlarged superior ophthalmic vein, cavernous sinus enlargement ipsilateral (same side) as the abnormality and possibly diffuse enlargement of all the extraocular muscles resulting from venous engorgement.
- Selective arteriography is used to evaluate arteriovenous fistulas.
- High resolution digital subtraction angiography may help in classifying CCF into dural and direct type and thus formulate a strategy to treat it either by a balloon or coil or both with or without preservation of parent ipsilateral carotid artery.
Management of the underlying defect is proportional to the severity of the clinical presentation. Leg swelling and pain is best evaluated by vascular specialists (vascular surgeons, interventional cardiologists, interventional radiologists) who both diagnose and treat arterial and venous diseases to ensure that the cause of the extremity pain is evaluated. The diagnosis needs to be confirmed with some sort of imaging that may include magnetic resonance venography, venogram and usually confirmed with intravascular ultrasound because the flattened vein may not be noticed on conventional venography. In order to prevent prolonged swelling or pain from the consequences of the backed up blood from the compressed iliac vein, flow needs to be improved out of the leg. Uncomplicated cases may be managed with compression stockings.
Severe May-Thurner syndrome may require thrombolysis if there is a recent onset of thrombosis, followed by angioplasty and stenting of the iliac vein after confirming the diagnosis with a venogram or an intravascular ultrasound. A stent may be used to support the area from further compression following angioplasty. As the name implies, there classically is not a thrombotic component in these cases, but thrombosis may occur at any time.
If the patient has extensive thrombosis, it may be appropriate to consider pharmacologic and/or mechanical (also known as pharmacomechanical) thrombectomy. This is currently being studied to determine whether this will decrease the incidence of post-thrombotic syndrome.
Median arcuate ligament syndrome is a diagnosis of exclusion. That is, the diagnosis of MALS is generally considered only after patients have undergone an extensive evaluation of their gastrointestinal tract including upper endoscopy, colonoscopy, and evaluation for gallbladder disease and gastroesophageal reflux disease (GERD).
The diagnosis of MALS relies on a combination of clinical features and findings on medical imaging. Clinical features include those signs and symptoms mentioned above; classically, MALS involves a triad of abdominal pain after eating, weight loss, and an abdominal bruit, although the classic triad is found in only a minority of individuals that carry a MALS diagnosis.
Diagnostic imaging for MALS is divided into screening and confirmatory tests. A reasonable screening test for patients with suspected MALS is duplex ultrasonography to measure blood flow through the celiac artery. Peak systolic velocities greater than 200 cm/s are suggestive of celiac artery stenosis associated with MALS.
Further evaluation and confirmation can be obtained via angiography to investigate the anatomy of the celiac artery. Historically, conventional angiography was used, although this has been largely replaced by less invasive techniques such as computed tomography (CT) and magnetic resonance (MR) angiography. Because it provides better visualization of intraabdominal structures, CT angiography is preferred to MR angiography in this setting. The findings of focal narrowing of the proximal celiac artery with poststenotic dilatation, indentation on the superior aspect of the celiac artery, and a hook-shaped contour of the celiac artery support a diagnosis of MALS. These imaging features are exaggerated on expiration, even in normal asymptomatic individuals without the syndrome.
Proximal celiac artery stenosis with poststenotic dilatation can be seen in other conditions affecting the celiac artery. The hook-shaped contour of the celiac artery is characteristic of the anatomy in MALS and helps distinguish it from other causes of celiac artery stenosis such as atherosclerosis. This hooked contour is not entirely specific for MALS however, given that 10-24% of normal asymptomatic individuals have this anatomy.
Treatment depends on the severity and symptoms. Treatments include:
- Endovascular stenting.
- Renal vein re-implantation.
- Gonadal vein embolization.
Diagnosis is very difficult, and usually one of exclusion. SMA syndrome is thus considered only after patients have undergone an extensive evaluation of their gastrointestinal tract including upper endoscopy, and evaluation for various malabsorptive, ulcerative and inflammatory instestinal conditions with a higher diagnostic frequency. Diagnosis may follow x-ray examination revealing duodenal dilation followed by abrupt constriction proximal to the overlying SMA, as well as a delay in transit of four to six hours through the gastroduodenal region. Standard diagnostic exams include abdominal and pelvic computed tomography (CT) scan with oral and IV contrast, upper gastrointestinal series (UGI), and, for equivocal cases, hypotonic duodenography. In addition, vascular imaging studies such as ultrasound and contrast angiography may be used to indicate increased bloodflow velocity through the SMA or a narrowed SMA angle.
Despite multiple case reports, there has been controversy surrounding the diagnosis and even the existence of SMA syndrome since symptoms do not always correlate well with radiologic findings, and may not always improve following surgical correction. However, the reason for the persistence of gastrointestinal symptoms even after surgical correction in some cases has been traced to the remaining prominence of reversed peristalsis in contrast to direct peristalsis.
Since females between the ages of 10 and 30 are most frequently afflicted, it is not uncommon for physicians to initially and incorrectly assume that emaciation is a choice of the patient instead of a consequence of SMA syndrome. Patients in the earlier stages of SMA syndrome often remain unaware that they are ill until substantial damage to their health is done, since they may attempt to adapt to the condition by gradually decreasing their food intake or naturally gravitating toward a lighter and more digestible diet.
Treatment depends on the anatomy of the malformation as determined by angiography or Magnetic Resonance Imaging (MRI).
Testing for a malformed vein of Galen is indicated when a patient has heart failure which has no obvious cause. Diagnosis is generally achieved by signs such as cranial bruits and symptoms such as expanded facial veins. The vein of Galen can be visualized using ultrasound or Doppler. A malformed Great Cerebral Vein will be noticeably enlarged. Ultrasound is a particularly useful tool for vein of Galen malformations because so many cases occur in infancy and ultrasound can make diagnoses prenatally. Many cases are diagnosed only during autopsy as congestive heart failure occurs very early.
It can be diagnosed with CT scan, angiography, transesophageal echocardiography, or cardiac MRI. Unfortunately, less invasive and expensive testing, such as transthoracic echocardiography and CT scanning are generally less sensitive.
As the cause of the ischemia can be due to embolic or thrombotic occlusion of the mesenteric vessels or nonocclusive ischemia, the best way to differentiate between the etiologies is through the use of mesenteric angiography. Though it has serious risks, angiography provides the possibility of direct infusion of vasodilators in the setting of nonocclusive ischemia.
There is a recent optical test, but it requires endoscopy (see Diagnosis). There are no specific blood tests for ischemic colitis. The sensitivity of tests among 73 patients were:
- The white blood cell count was more than 15,000/mm3 in 20 patients (27%)
- The serum bicarbonate level was less than 24 mmol/L in 26 patients (36%)
Plain X-rays are often normal or show non-specific findings. In a series of 73 patients, plain abdominal radiography (56%) showing colic distension in 53% or a pneumoperitoneum in 3%.
CT scans are often used in the evaluation of abdominal pain and rectal bleeding, and may suggest the diagnosis of ischemic colitis, pick up complications, or suggest an alternate diagnosis.
Endoscopic evaluation, via colonoscopy or flexible sigmoidoscopy, is the procedure of choice if the diagnosis remains unclear. Ischemic colitis has a distinctive endoscopic appearance; endoscopy can also facilitate alternate diagnoses such as infection or inflammatory bowel disease. Biopsies can be taken via endoscopy to provide more information. Visible light spectroscopy, performed using catheters placed through the 5 mm channel of the endoscope, is diagnostic (see Diagnosis).
History and examination by a physician with characteristic signs and symptoms are sufficient in many cases in ruling out systemic causes of venous hypertension such as hypervolemia and heart failure. An ultrasound (usually a lower limbs venous ultrasonography) can detect venous obstruction or valvular incompetence as the cause, and is used for planning venous ablation procedures, but it is not necessary in suspected venous insufficiency where surgical intervention is not indicated.
There are few studies of the long-term outcomes of patients treated for MALS. According to Duncan, the largest and more relevant late outcomes data come from a study of 51 patients who underwent open surgical treatment for MALS, 44 of whom were available for long-term follow-up at an average of nine years following therapy. The investigators reported that among patients who underwent celiac artery decompression and revascularization, 75% remained asymptomatic at follow-up. In this study, predictors of favorable outcome included:
- Age from 40 to 60 years
- Lack of psychiatric condition or alcohol use
- Abdominal pain that was worse after meals
- Weight loss greater than 20 lb (9.1 kg)
The mainstay of treatment for CCF is endovascular therapy. This may be transarterial (mostly in the case of direct CCF) or transvenous (most commonly in indirect CCF). Occasionally, more direct approaches, such as direct transorbital puncture of the cavernous sinus or cannulation of the draining superior orbital vein are used when conventional approaches are not possible. Spontaneous resolution of indirect fistulae has been reported but is uncommon. Staged manual compression of the ipsilateral carotid has been reported to assist with spontaneous closure in selected cases.
Direct CCF may be treated by occlusion of the affected cavernous sinus (coils, balloon, liquid agents), or by reconstruction of the damaged internal carotid artery (stent, coils or liquid agents).
Indirect CCF may be treated by occlusion of the affected cavernous sinus with coils, liquid agents or a combination of both.
A "Partial anomalous pulmonary venous connection" (or "Partial anomalous pulmonary venous drainage" or "Partial anomalous pulmonary venous return") is a congenital defect where the left atrium is the point of return for the blood from some (but not all) of the pulmonary veins.
It is less severe than total anomalous pulmonary venous connection which is a life-threatening anomaly requiring emergent surgical correction, usually diagnosed in the first few days of life. Partial anomalous venous connection may be diagnosed at any time from birth to old age. The severity of symptoms, and thus the likelihood of diagnosis, varies significantly depending on the amount of blood flow through the anomalous connections. In less severe cases, with smaller amounts of blood flow, diagnosis may be delayed until adulthood, when it can be confused with other causes of pulmonary hypertension. There is also evidence that a significant number of mild cases are never diagnosed, or diagnosed incidentally. It is associated with other vascular anomalies, and some genetic syndromes such as Turner syndrome.
Computed tomography (CT scan) is often used. The accuracy of the CT scan depends on whether a small bowel obstruction (SBO) is present.
SBO absent
- prevalence of mesenteric ischemia 23%
- sensitivity 64%
- specificity 92%
- positive predictive value (at prevalence of 23%) 79%
- negative predictive value (at prevalence of 23%) 95%
SBO present
- prevalence of mesenteric ischemia 62%
- sensitivity 83%
- specificity 93%
- positive predictive value (at prevalence of 62%) 93%
- negative predictive value (at prevalence of 62%) 61%
Findings on CT scan include:
- Mesenteric edema
- Bowel dilatation
- Bowel wall thickening
- Intramural gas
- Mesenteric stranding
Since it is a rare disease, it remains a diagnosis of exclusion of other conditions with similar symptoms. The diagnosis is supported by the results of imaging studies such as computed tomography or magnetic resonance imaging, ultrasound of the abdomen (with or without doppler imaging) or intravenous urography.
Specialist vascular ultrasonographers should routinely look for left ovarian vein reflux in patients with lower limb varices especially if not associated with long or short saphenous reflux. The clinical pattern of varices differs between the two types of lower limb varices.
CT scanning is used to exclude abdominal or pelvic pathology. CT-Angiography/Venography can often demonstrate left ovarian vein reflux and image an enlarged left ovarian vein but is less sensitive and much more expensive than duplex Doppler ultrasound examination. Ultrasound requires that the ultrasonographer be experienced in venous vascular ultrasound and so is not always readily available. A second specialist ultrasound exam remains preferable to a CT scan.
As a wide range of pelvic and abdominal pathology can cause symptoms consistent with those symptoms due to left ovarian vein reflux, prior to embolisation of the left ovarian vein, a careful search for such diagnoses is essential. Consultation with general surgeons, gynaecologists, and possibly CT scanning should always be considered.
With acutely ill patients, consider emergency surgery laparotomy if there is a high index of suspicion.
Plain radiography may demonstrate signs of duodenal obstruction with dilatation of the proximal duodenum and stomach but it is often non-specific. Upper gastrointestinal series is the modality of choice for the evaluation of malrotation as it will show an abnormal position of the duodeno-jejunal flexure (ligament of Treitz). In cases of malrotation complicated with volvulus, it demonstrates a corkscrew appearance of the distal duodenum and jejunum. In cases of obstructing Ladd bands, it will reveal a duodenal obstruction.
In equivocal cases, contrast enema, may be helpful by showing the caecum at an abnormal location.
It is usually discovered near birth, but in some cases is not discovered until adulthood. In adults, the "whirlpool sign" of the superior mesenteric artery can be useful in identifying malrotation.
Delay in the diagnosis of SMA syndrome can result in fatal catabolysis (advanced malnutrition), dehydration, electrolyte abnormalities, hypokalemia, acute gastric rupture or intestinal perforation (from prolonged mesenteric ischemia), gastric distention, spontaneous upper gastrointestinal bleeding, hypovolemic shock, and aspiration pneumonia.
A 1-in-3 mortality rate for Superior Mesenteric Artery syndrome has been quoted by a small number of sources. However, after extensive research, original data establishing this mortality rate has not been found, indicating that the number is likely to be unreliable. While research establishing an official mortality rate may not exist, two recent studies of SMA syndrome patients, one published in 2006 looking at 22 cases and one in 2012 looking at 80 cases, show mortality rates of 0% and 6.3%, respectively. According to the doctors in one of these studies, the expected outcome for SMA syndrome treatment is generally considered to be excellent.
May-Thurner syndrome (MTS) is thought to represent between two and five percent of lower-extremity venous disorders. May-Thurner syndrome is often unrecognized; however, current estimates are that this condition is three times more common in women than in men. The classic syndrome typically presents in the second to fourth decades of life. In the 21st century in a broader disease profile, the syndrome acts as a permissive lesion and becomes symptomatic when something else happens such as, following trauma, a change in functional status such as swelling following orthopaedic joint replacement.
It is important to consider May-Thurner syndrome in patients who have no other obvious reason for hypercoagulability and who present with left lower extremity thrombosis. To rule out other causes for hypercoagulation, it may be appropriate to check the antithrombin, protein C, protein S, factor V Leiden, and prothrombin G20210A.
Venography will demonstrate the classical syndrome when causing deep venous thrombosis.
May-Thurner syndrome in the broader disease profile known as nonthrombotic iliac vein lesions (NIVLs) exists in the symptomatic ambulatory patient and these lesions are usually not seen by venography. Morphologically, intravascular ultrasound (IVUS) has emerged as the best current tool in the broader sense. Functional testing such as duplex ultrasound, venous and interstitial pressure measurement and plethysmography may sometimes be beneficial. Compression of the left common iliac vein may be seen on pelvic CT.
Diagnosis of gastric varices is often made at the time of upper endoscopy.
The Sarin classification of gastric varices identifies four different anatomical types of gastric varices, which differ in terms of treatment modalities.
Unlike oesophageal varices, rectal varices are less prone to bleeding, are less serious when a bleed does occur, and are easier to treat because of the more accessible location.
Typically, treatment consists of addressing the underlying portal hypertension. Some treatments include portosystemic shunting, ligation, and under-running suturing. Insertion of a transjugular intrahepatic portosystemic shunt (TIPS) has been shown to alleviate varices caused by portal hypertension. Successful treatment of portal hypertension that subsequently reduces anorectal varices provides a confirmation of the initial diagnosis, allowing for a distinction between varices and hemorrhoids, which would not have been alleviated by reduction of portal hypertension.
The exact incidence of ischemic colitis is difficult to estimate, as many patients with mild ischemia may not seek medical attention. Ischemic colitis is responsible for about 1 in 2000 hospital admissions, and is seen on about 1 in 100 endoscopies. Men and women are affected equally; ischemic colitis is a disease of the elderly, with more than 90% of cases occurring in people over the age of 60.
Surgical decompression can be achieved by opening the abdominal wall and abdominal fascia anterior in order to physically create more space for the abdominal viscera. Once opened, the fascia can be bridged for support and to prevent loss of domain by a variety of medical devices (Bogota bag, artificial bur, and vacuum devices using negative pressure wound therapy ).
Venous Insufficiency Conservative, Hemodynamic and Ambulatory treatment" is an ultrasound guided, minimally invasive surgery strategic for the treatment of varicose veins, performed under local anaesthetic. CHIVA is an abbreviation from the French "Cure Conservatrice et Hemodynamique de l'Insufficience Veineuse en Ambulatoire".