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Pulmonary artery dissection: MR findings.

We report a case of pulmonary artery dissection imaged by MR. Dissection of a markedly dilated pulmonary artery is a rare and usually fatal complication of chronic pulmonary arterial hypertension. The diagnosis is made at autopsy, with only two cases having previously been documented (by Doppler echocardiography) during life. The hallmark of an arterial dissection is the finding of an intimal flap and a false lumen. In our case, spin echo MR imaging failed to show either the intimal flap or any intraluminal signal defects. The dissection was presumably obscured by nonhomogeneous intraluminal signal caused by the slow blood flow associated with severe pulmonary arterial hypertension. Cine MR imaging, however, demonstrated different signal intensity within the true and false lumens of the dissection, thereby outlining the intimal flap between the two channels.

Adult↗

Exercise-related dissection of craniocervical arteries: CT, MR, and angiographic findings.

OBJECTIVE: Our goal was to demonstrate the spectrum of neuroradiologic (CT, MR, and angiographic) findings in craniocervical arterial dissection (CAD) related to exercise or sporting activities and compare the diagnostic utility of CT, MRI, and MR angiography (MRA). MATERIALS AND METHODS: The neuroradiologic examinations of 11 patients with CAD was performed: CT was performed in 10 patients, cranial MRI in 9, cranial and cervical MRA in 4, and contrast angiography in 10. The CT examinations were assessed for the presence of an infarction or a hyperdense artery (consistent with intraluminal thrombus), MRI examinations for the presence of infarction or abnormal periarterial signal, and contrast angiograms for arterial stenosis or occlusion, luminal irregularity, pseudoaneurysm, intimal flap, or distal branch occlusions. RESULTS: Computed tomography demonstrated infarction in four patients. At contrast angiography, a dissection was found in the artery supplying the region of infarction in all cases. A hyperdense artery was found by CT in two patients, which correlated with dissection of the artery or its parent artery on contrast angiography. Cranial MRI findings were seen in six patients (infarction in five, periarterial signal abnormality in five). Dissection was confirmed in all four patients with abnormal periarterial signal who underwent contrast angiography. Two patients with abnormal intracranial periarterial signal had corresponding abnormalities on MRA. False-negative cranial and cervical MRI and MRA studies were performed in one patient because the imaging volumes used for the cervical and intracranial MR examinations did not overlap. Four patients with normal intracranial arterial signal had dissection in the neck demonstrated by contrast angiography. CONCLUSION: Neuroradiologic findings of CAD can include infarction, a hyperdense artery on CT, abnormal periarterial signal on MRI, and a narrowed arterial signal column on MRA. Computed tomography is an insensitive screening examination. Proper use of MRI and MRA involves examination of both the head and the neck with overlapping imaging volumes of the two regions.

Adolescent↗

Planned early neck dissection before radiation for persistent neck nodes after induction chemotherapy.

Optimal management of advanced neck metastases as part of an organ preservation treatment approach for head and neck squamous carcinoma (HNSC) is unclear. Since 1989, our management paradigm for patients on organ preservation was modified to incorporate planned early neck dissection before radiation therapy for patients who did not achieve a complete response (CR) of neck nodes after induction chemotherapy (IC). The purpose of this study was to determine if planned early neck dissection is a safe and effective approach in the management of advanced nodal disease as part of organ preservation. Fifty-eight consecutive patients with advanced HNSC who were entered in organ preservation trials using induction chemotherapy and radiation with surgical salvage were studied. Median follow-up was 26 months. Of the 58 patients, 71% were stage IV. Patients were grouped by nodal response to chemotherapy and N class, and were analyzed with respect to patterns of recurrence, complications, and survival. Overall, the rate of CR of neck nodes was 49%. Fifty-one percent had less than a complete response of neck nodes after IC and required planned early neck dissection. There were no significant differences in patterns of recurrence, complications, interval time to start of radiation, recurrence, or survival rates between the CR and less than CR groups. These data suggest that planned early neck dissection for patients with less than CR in the neck after IC is not detrimental with respect to neck relapse or overall survival. We believe that planned early neck dissection can be safely incorporated into future organ preservation treatment protocols for patients with advanced head and neck carcinoma.

Adult↗

External beam radiation followed by planned neck dissection and brachytherapy for base of tongue squamous cell carcinoma.

BACKGROUND: Surgical resection of tongue base cancer can leave the patient with significant functional deficits. Other therapies, such as external beam radiation followed by neck dissection and radiation implants, have shown equal tumor control with good functional outcome. METHODS: Between March 1991 and July 1999, 12 patients at Oregon Health Sciences University, the Portland Veterans Administration Medical Center and West Virginia University School of Medicine Hospital were treated with external beam radiation followed by neck dissection and Ir192 implants. Two patients had T1 disease, two had T2, five patients had T3 tumors, and three had T4 tumors. Six had N2a necks, three had N2b necks, and three had N2c. Follow-up ranged from 13 months to 8 years. RESULTS: After external beam radiation, five patients had complete response and seven had partial response in the neck without complications. One patient underwent a unilateral radical neck dissection, eight had unilateral selective neck dissections involving levels I to IV, and three had dissections involving levels I to III. One of the five patients who had a complete clinical response in the neck had pathologically positive nodes. One patient had a pulmonary embolus that was treated and had no permanent sequelae. There were three complications from brachytherapy. Two patients had soft tissue necrosis at the primary site and one patient had radionecrosis of the mandible. All healed without further therapy. One patient had persistent disease and underwent a partial glossectomy but died of local disease. Distant metastasis developed in two patients. All others show no evidence of disease and are able to eat a normal diet by mouth. CONCLUSION: This combination of therapies should be considered when treating tongue base cancer.

Aged↗

Combined radiotherapy with planned neck dissection for small head and neck cancers with advanced cervical metastases.

BACKGROUND: We have previously described our treatment algorithm for patients with small head and neck cancers with advanced cervical metastases (stage N2 or greater). Primary radiotherapy is given to the primary site and neck, followed 6 weeks later with endoscopy and biopsy of the primary site. If biopsy of the primary site is negative by frozen section, an immediate neck dissection is performed even when no clinical residual neck disease is present. Our initial review found that 36% of patients with a complete clinical response to radiotherapy had positive nodes on histological examination. STUDY DESIGN: Retrospective. METHODS: The medical records of 71 patients treated at UCLA Medical Center from 1986 to 1999 by this algorithm were reviewed. RESULTS: After radiotherapy, 69 of 71 patients had a complete response at their primary site. Forty-two patients had a complete clinical response in the neck. Seventy-one neck dissections were performed. Overall, 31 of 71 neck dissections (44%) had positive nodes. Among the 42 patients with a complete response to radiotherapy, 13 (31%) had positive histological nodes. Among the 29 patients with a partial response to radiotherapy, 17 (59%) had positive nodes. Follow-up and incidence of neck recurrence are discussed. CONCLUSION: Planned neck dissection for advanced cervical metastases remains controversial for patients with a complete clinical response to radiotherapy. However, our results suggest that clinical assessment after radiotherapy cannot assure the absence of neck disease. Until there are reliable methods to distinguish which patients are truly free of neck disease, we believe the benefits of a planned neck dissection outweigh the low morbidity of this procedure.

Adult↗

Selective neck dissection for the treatment of neck metastasis from squamous cell carcinoma of the head and neck.

OBJECTIVE: Our objective was to determine the proportion of patients disease free in the neck, with the primary site controlled, who have been treated with a selective neck dissection (SND) for squamous cell carcinoma (SCCa) of the upper aerodigestive tract, and who had cervical metastasis less than 3 cm. STUDY DESIGN: A cohort of patients who fit the inclusion/exclusion criteria was identified retrospectively. Then all surviving patients were followed for a minimum of 2 years. METHODS: A group of 52 patients who had 58 selective neck dissections for cervical metastases from SCCa of the upper aerodigestive tract were identified. The mean age was 56 years (range, 20-85 y), there were 40 males and 12 females, and mean follow-up was 24.5 months (range, 1-64 mo). Twenty-six patients had clinically negative (cNo) neck examinations and 26 had clinically positive neck examinations. Postoperative radiation was given for extracapsular spread, greater than 2 positive nodes, T3, T4, or recurrent disease if the patient had not received radiation before surgery. These radiation criteria excluded 18 patients from postoperative radiation treatment. RESULTS: Kaplan-Meier survival analysis showed that the regional control rate with the primary site controlled was 0.94. Six patients developed recurrent neck disease. Three of these 6 patientswere surgically salvaged. Four recurrences were in the dissected field and 2 were out of the dissected field (level V). CONCLUSIONS: With similar indications for radiation therapy, the regional control rate in this cohort is comparable to control rates obtained with modified radical neck dissection.

Adult↗

Safety of modified radical neck dissection for differentiated thyroid carcinoma.

OBJECTIVES/HYPOTHESIS: The management of cervical metastases from differentiated thyroid carcinoma (DTC) remains controversial. Most surgeons perform a neck dissection (ND) for clinically apparent disease. The extent of nodal dissection varies from regional to comprehensive. Morbidity from ND in the setting of DTC remains high, particularly when performed in the setting of a thyroidectomy (TT). To determine complications from ND for DTC, we retrospectively reviewed our surgical experience of modified radical neck dissection for nodal metastases. STUDY DESIGN: Retrospective chart review. METHODS: Between 1997 and 2002, 39 consecutive patients (31 females and 8 males) underwent 44 comprehensive NDs of levels II-V for DTC. Central compartment dissection (CCD) (levels VI and VII) was also performed during 23 of these procedures. Twenty (45.5%) patients had prior treatment elsewhere. Preoperative pathology revealed papillary carcinoma in 22 patients (56.4%), tall cell variant in 11 (28.2%), and follicular variant in 6 (15.4%). RESULTS: Ten patients (20%) underwent ND alone, whereas 6 (14%) underwent simultaneous ND and TT. Fifteen patients underwent simultaneous ND, TT, and CCD (30%). Temporary hypocalcemia occurred after 21% of NDs that were performed in the setting of either TT or CCD or both. There were no cases of permanent hypoparathyroidism. Transient regional lymph node (RLN) paresis occurred in two patients and was associated with a concomitant central compartment nodal dissection; there were no permanent RLN palsies. Transient spinal accessory nerve paresis developed after 27% of NDs performed. Two patients developed chyle leaks. CONCLUSIONS: When ND is necessary for the treatment of thyroid malignancies, the procedure can be performed safely with acceptable morbidity.

Adolescent↗

Cervicocranial arterial dissection.

Dissection of the cervicocranial arteries is becoming more frequently recognized as a cause of neurological disorders. Typical clinical features seen with dissection include unilateral headache, oculosympathetic palsy, amaurosis fugax, and symptoms of focal brain ischemia. The diagnosis of carotid or intracranial dissection is usually best confirmed by angiography, although magnetic resonance imaging and computed tomography have been shown to visualize intimal dissection. The prognosis in cases of spontaneous dissection is generally benign unless the initial manifestation involves infarction with substantial deficit. The best approach to treatment appears to be the administration of the anticoagulant, heparin, followed by warfarin or antiplatelet therapy. Surgical intervention is reserved for cases of progressive or recurrent ischemic complication that occurs despite the administration of adequate doses of anticoagulants.

Aortic Dissection↗

Intracranial aneurysms and cervicocephalic arterial dissections associated with congenital heart disease.

OBJECTIVE: The number of patients with congenital heart disease who survive to adolescence and adulthood continues to increase. We review our experience with noninfectious intracranial aneurysms and cervicocephalic arterial dissections in patients with congenital heart disease, expanding the clinical spectrum of the cerebrovascular abnormalities that may be encountered in this group of patients. METHODS: All patients with congenital heart disease and intracranial aneurysms of cervicocephalic arterial dissections, who were evaluated at the Mayo Clinic between 1969 and 1992, were identified. RESULTS: Congenital heart disease was diagnosed in 3 (8%) of 36 children with intracranial aneurysms, in 5 (0.3%) of 1994 adults with intracranial aneurysms, in 1 (4%) of 25 children with cervicocephalic arterial dissections, and in 5 (2%) of 250 adults with cervicocephalic arterial dissections. The mean age of the 14 patients was 32 years (range, 13-58 yr). The congenital heart disorders consisted of complex cardiac anomalies in three patients (truncus arteriosus, transposition of the great arteries, and tricuspid atresia in one patient each), pulmonic valve or arterial stenosis in two patients, aortic coarctation in four patients, and bicuspid aortic valve in five patients. Only one patient had an intracranial aneurysm and coarctation of the aorta. CONCLUSION: Individuals with a variety of congenital heart disorders may be at an increased risk of intracranial aneurysm development and cervicocephalic arterial dissection, particularly in adolescence. The muscular arteries of the head and neck are derived from neural crest cells and the neural crest is also of major importance in early cardiac development, suggesting that an abnormality of the neural crest may be the common pathogenetic factor explaining this association.

Adolescent↗

A dissecting aneurysm of the posteroinferior cerebellar artery: case report.

OBJECTIVE AND IMPORTANCE: We present a patient who experienced a subarachnoid hemorrhage secondary to a dissecting aneurysm of the right posteroinferior cerebellar artery (PICA). The use of an encircling clip in treating the aneurysm while preserving supply to brain stem perforators originating near the dissecting segment and the distal PICA territory was key in the operative management. CLINICAL PRESENTATION: A 48-year-old patient with a history of hypertension presented with subarachnoid hemorrhage confirmed by computed tomography of the brain. Successive cerebral angiography revealed a dynamic change in the configuration of the dissection, with expansion of the associated focal ectasia. OPERATIVE MANAGEMENT: At surgery, three brain stem perforators adjacent to the aneurysm were visualized. The dissecting segment was reconstructed with an encircling Sundt clip and muslin wrap, which preserved the flow through the PICA and brain stem perforators. CONCLUSION: A patient suffering from a dissecting PICA aneurysm and subarachnoid hemorrhage was successfully treated with direct surgical reconstruction of the parent artery, sparing the perforators to the medulla.

Aortic Dissection↗

Treatment of symptomatic cervical carotid dissections with endovascular stents.

OBJECTIVE: Symptomatic dissections of the cervical carotid artery (CCA) can be spontaneous or secondary to trauma and may be associated with pseudoaneurysms. Surgical treatment is often difficult or unavailable. We report the successful use of endovascular stents in the treatment of symptomatic dissection of the CCA. METHODS: Five consecutive patients with symptomatic CCA dissection were seen at our institution. There were four female patients and one male patient, ranging in age from 19 to 56 years. One dissection was spontaneous. The others were secondary to a gunshot wound (one patient), blunt neck trauma (two patients), and endovascular treatment of atherosclerotic carotid bifurcation disease (one patient). Balloon-expandable and self-expanding stents were placed via a transfemoral approach. RESULTS: Success in restoring the carotid lumen with two to five stents in each patient was angiographically demonstrated. There were no procedure-related complications. All patients experienced significant clinical improvement within the first 24 hours and complete long-term recovery. CONCLUSION: Symptomatic dissections of the CCA can be successfully treated by using endovascular stents.

Adult↗

Tandem intracranial stent deployment for treatment of an iatrogenic, flow-limiting, basilar artery dissection: technical case report.

OBJECTIVE AND IMPORTANCE: Intimal dissection constitutes one of the complications associated with angioplasty of intracranial vessels. We present a case of iatrogenic dissection of the entire basilar artery, which was induced by angioplasty and stenting of symptomatic, focal, intracranial vertebral artery stenosis, and its successful treatment with tandem deployment of a downstream stent. CLINICAL PRESENTATION: A 61-year-old, hypertensive, renal transplant recipient presented with orthostatic vertebrobasilar insufficiency that was refractory to medical management, including anticoagulation therapy. Angiography revealed an occluded right vertebral artery and focal, high-grade, left intracranial vertebral artery stenosis. Magnetic resonance imaging showed multiple posterior fossa infarctions. The left intracranial vertebral artery stenosis was successfully treated with primary stent deployment and balloon angioplasty, with symptom resolution. On postprocedure Day 2, the patient noted worsening right hemiparesis. INTERVENTION: Subsequent angiography revealed a flow-limiting, windsock-type, basilar artery dissection beginning at the distal end of the left vertebral artery stent and extending to the origin of the left posterior cerebral artery. A tandem stent was navigated intracranially and deployed past the first one, successfully sealing the dissection inflow zone and reconstituting normal flow to the top of the basilar artery. A clinical follow-up examination at 3 months revealed no further orthostatic symptoms and only mild residual right-sided weakness. CONCLUSION: This is the first description of iatrogenic stent-induced dissection of the entire basilar artery that was successfully treated by inflow zone control via tandem intracranial stent deployment.

Aortic Dissection↗

Long-term outcomes after carotid stent placement treatment of carotid artery dissection.

OBJECTIVE: To assess the long-term outcomes after stent placement for the treatment of carotid artery dissections. METHODS: Between 1992 and 1998, seven patients underwent stenting procedures for treatment of extracranial carotid artery dissections resulting from various causes, including trauma (n = 2), iatrogenesis (n = 2), spontaneous development (n = 2), and fibromuscular dysplasia (n = 1). Stenting procedures were performed for large, nonhealing, dissection-induced pseudoaneurysms (four cases) or severe preocclusive stenosis (three cases). A total of 11 stents were placed (Palmaz stents, n = 8; Wallstents, n = 3). Radiological follow-up examinations were performed after a mean period of 17.7 months (range, 1-67 mo), using conventional or computed tomographic angiography. Clinical follow-up data were obtained after a mean period of 42.9 months (range, 13-72 mo). RESULTS: All stent placements resulted in complete resolution of dissection-induced stenosis. For two of the four patients with aneurysms, the lesions occluded spontaneously at the time of the procedure. The third patient required coil embolization of the pseudoaneurysm. One patient exhibited progressive shrinkage of the aneurysm in serial follow-up examinations, with healing after 18 months. No clinical complications were associated with the procedures. One patient exhibited progression to asymptomatic occlusion 3 months after stenting. The remaining six patients exhibited no significant changes in luminal diameters. All patients remained in clinically stable condition, with no ischemic symptoms, during more than 3.5 years (mean period) of follow-up monitoring. CONCLUSION: This experience suggests that stents placed for treatment of extracranial carotid artery dissections remain patent and patients remain free of symptoms on a long-term basis. Additional studies will be required to determine the optimal types of stents and intervals for follow-up monitoring using imaging.

Adolescent↗

Management of intracranial vertebral artery dissections initially presenting without subarachnoid hemorrhage.

OBJECTIVE: The clinical and angiographic follow-up results for intracranial vertebral artery (VA) dissections that initially presented without subarachnoid hemorrhage (SAH) were retrospectively investigated, to clarify their management. METHODS: Twenty-one patients with VA dissections that initially presented without SAH were studied. Initial angiography revealed aneurysmal dilation in 11 cases (typical pearl-and-string sign in 8 cases, aneurysmal dilation only in 2, and aneurysmal dilation with double-lumen sign in 1), occlusion in 7, double-lumen sign in 2, and string-like stenosis in 1. Nine patients (six with pearl-and-string sign, one with occlusion with aneurysmal dilations, and two with double-lumen sign), including three patients who experienced subsequent SAH, underwent endovascular proximal parent artery occlusion. The other 12 patients were treated conservatively. All patients were monitored with magnetic resonance angiography or digital subtraction angiography. RESULTS: Three patients experienced subsequent SAH, 1 day (two patients) or 51 months after onset. Follow-up angiographic assessments of the 20 patients demonstrated complete resolution in five cases, reduction of aneurysmal dilation in one case, and partial recanalization in one case. However, enlargement or formation of an aneurysmal dilation was recognized in four cases and progression of dissection was observed in one case. Eighteen patients experienced good recoveries, and three patients demonstrated moderate disabilities as a result of the initial ischemic insult. CONCLUSION: The risk of bleeding from unruptured VA dissections is higher than previously considered. Therefore, endovascular treatment should be considered for patients with VA dissections with relatively large or growing aneurysmal dilations.

Adult↗

A 5-year study of the transmalar subperiosteal midface lift with minimal skin and superficial musculoaponeurotic system dissection: a durable, natural-appearing lift with less surgery and recovery time.

The transmalar subperiosteal midface lift is a simple, direct-approach procedure to be performed with a meloplasty. The entry into the midface is at the site of maximum suture tension, which allows for more elevation. The skin is elevated enough to expose the entry site, which is on the zygoma just cephalad to the origins of the zygomaticus muscles. Through a small hole at that site, a periosteal elevator is used for the midface dissection. This is a blind dissection, and the technique is described. The advantages of the technique are that there is (1) no lower-lid incision or risk of an ectropion, (2) a resultant tightening and elevation of the lower lid, (3) more elevation and durability because the zygomaticus muscle origins are elevated with the periosteum and are sutured to the very substantial deep temporal fascia, (4) a simple and fast procedure, and (5) no telltale sign of a face lift. Both the superficial musculoaponeurotic system (SMAS) and the skin are substantially elevated with the transmalar subperiosteal midface lift to the extent that they should be only minimally dissected. In the author's opinion, the extended dissection of the skin and/or the SMAS does not increase the amount of tissue lift and probably reduces it in most cases, considering that the goal is a natural look and not one that appears pulled or stretched. The skin is elevated only for exposure, and the SMAS is elevated only enough to create a preauricular SMAS-platysma flap to tighten the neck. With two fewer layers of dissection, there is significantly less postoperative swelling and recovery time. The article presents the technique, the results on 272 patients over a period of 5 years, and a discussion. No patients described have had secondary procedures such as lasers, so the transmalar subperiosteal midface lift can be evaluated on its own merit.

Dissection↗

Risk factors and precipitating neck movements causing vertebrobasilar artery dissection after cervical trauma and spinal manipulation.

STUDY DESIGN: Potential precipitating events and risk factors for vertebrobasilar artery dissection were reviewed in an analysis of the English language literature published before 1993. OBJECTIVES: To assess the literature pertaining to precipitating neck movements and risk factors for vertebrobasilar artery dissection in an attempt to determine whether the incidence of these complications can be minimized. SUMMARY OF BACKGROUND DATA: Vertebrobasilar artery dissection and occlusion leading to brain stem and cerebellar ischemia and infarction are rare but often devastating complications of cervical, manipulation and neck trauma. Although various investigators have suggested potential risk factors and precipitating events, the basis for these suggestions remains unclear. METHODS: A detailed search of the literature using three computerized bibliographic databases was performed to identify English language articles from 1966 to 1993. Literature before 1966 was identified through a hand search of Index Medicus. References of articles obtained by database search were reviewed to identify additional relevant articles. Data presented in all articles meeting the inclusion criteria were summarized. RESULTS: The 367 case reports included in this study describe 160 cases of spontaneous onset, 115 cases of onset after spinal manipulation, 58 cases associated with trivial trauma, and 37 cases caused by major trauma (3 cases were classified in two categories). The nature of the precipitating trauma, neck movement, or type of manipulation that was performed was poorly defined in the literature, and it was not possible to identify a specific neck movement or trauma that would be considered the offending activity in the majority of cases. There were 208 (57%) men and 158 (43%) women (gender data not reported in one case) with an average age of 39.3 +/- 12.9 years. There was an overall prevalence of 13.4% hypertension, 6.5% migraines, 18% use of oral contraception (percent of female patients), and 4.9% smoking. In only isolated cases was specific vascular disease such as fibromuscular hyperplasia noted. CONCLUSIONS: The literature does not assist in the identification of the offending mechanical trauma, neck movement, or type of manipulation precipitating vertebrobasilar artery dissection or the identification of the patient at risk. Thus, given the current status of the literature, it is impossible to advise patients or physicians about how to avoid vertebrobasilar artery dissection when considering cervical manipulation or about specific sports or exercises that result in neck movement or trauma.

Aortic Dissection↗

Epineural dissection is a safe technique that facilitates limb salvage surgery.

UNLABELLED: Epineural dissection has been used in our center for the past 19 years as a means of preserving the sciatic nerve when it is closely applied to a soft tissue sarcoma. Our aim in doing this study was to establish if this technique resulted in increased local or systemic recurrence of the tumor. In addition, we assessed functional outcomes. Forty-three patients had an epineural dissection done during primary resection of a malignant thigh tumor. These patients were compared with 44 patients with tumors that were of similar size and grade but distant from the nerve. We also analyzed seven patients who required nerve resection. There was no difference in local or systemic recurrence rates or functional outcomes when epineural dissection was done. Those with nerve resection had worse Musculoskeletal Tumor Society scores but equivalent Toronto Extremity Salvage Scores to those with an epineural dissection. We conclude that epineural dissection (when combined with radiotherapy in a planned multidisciplinary approach to limb salvage) is both a safe and effective procedure to preserve the sciatic nerve and that nerve resection should be limited to situations where the nerve is completely encased in tumor. LEVEL OF EVIDENCE: Prognostic study, Level II-2 (retrospective cohort study). See the Guidelines for Authors for a complete description of levels of evidence.

Cohort Studies↗

Dynamic aortic obstruction in a patient with acute type B dissection.

There are at least 7000 aortic dissections diagnosed in the United States each year. Type B dissections accounted for 38% of cases enrolled in the prospective International Registry of Aortic Dissection. We report a case of a 48-year-old hypertensive woman with an acute type B aortic dissection causing significant dynamic obstruction of the aorta. Intravascular ultrasound of her aorta revealed a mobile intimal flap nearly obliterating the true lumen with each systolic contraction. Simultaneous pressure tracings obtained from her ascending aorta and femoral artery demonstrated a systolic pressure gradient in excess of 100 mm Hg. The patient developed progressive renal failure and ultimately underwent successful operative replacement of the proximal descending thoracic aorta with a Dacron graft. In this case presentation, we highlight the unusual physiology exemplified by this case and explore contemporary management strategies for complicated type B aortic dissection, including surgery and catheter-based techniques.

Aortic Dissection↗