Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “FENESTRATION”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,729 records · Page 96Linked to original sources
PubMed2001

Endoscopic surgery for large posterior fossa arachnoid cysts.

The authors report two cases of large arachnoid cysts of the posterior fossa treated by endoscopic surgery. One patient underwent a successful endoscopic cyst fenestration by burr hole approach after several procedures of shunt revision. In another an endoscope-assisted microsurgical intervention was necessary. Lateral (cerebellar or cerebellopontine angle) cysts, as two reported cases, may be treated through a lateral retromastoid approach by fenestration into the prepontine cistern and eventually into the cisterna magna. We advise to start the operation through a burr hole and to try to realize the fenestration by endoscopy only. If this attempt fails, an endoscope-assisted microsurgical technique may be performed by enlarging the craniectomy. In this last instance the endoscope is useful particularly deeply to fenestrate the anterior cyst wall in the prepontine or ambient cisterns, where it provides more illumination and helps to identify the nervous and vascular structures.

Adult↗
PubMed2003

Giant cyst of the cavum septi pellucidi, cavum Vergae and veli interpositi.

The authors report a case study of a giant cyst of the cavum septi pellucidi, cavum Vergae and veli interpositi spreading to the posterior fossa, and initially treated elsewhere by ventriculoperitoneal shunt, with no resolution of the symptomatology. A few months later the patient was successfully treated by fenestration into the ventricular system through a neuroendoscopic technique, at the Pediatric Neurosurgical Center of the Meyer Children's Hospital in Florence. Symptomatic midline cysts are quite rare and different techniques have been proposed for their treatment, i. e., direct craniotomy, conventional shunting, stereotactic approaches as well as endoscopic fenestration. In such cases neuroendoscopy obtains a good symptom resolution level, avoiding at the same time the risks of damage to endoventricular structures and often eliminates the need for a definitive ventriculoperitoneal shunt. In the present research the authors analyze the anatomy of the midline cavities and the mechanism through which a cyst may become symptomatic. The surgical endoscopic technique and the clinical and radiological assessments which confirmed the patency of the fenestration are also discussed. The authors conclude that endoscopic ventricular fenestration may represent the treatment of choice for this pathology.

Central Nervous System Cysts↗
PubMed2005

Endoscopic treatment of quadrigeminal cistern arachnoid cysts.

Five patients with arachnoid cysts of the quadrigeminal cistern treated by endoscopic fenestration are reported and another eleven well-documented cases from the literature are reviewed. Among the five personal cases four were children and one was adult; the cyst fenestration was performed from the lateral ventricle in three cases and from the third ventricle in two. In four patients the endoscopic treatment resulted in clinical remission, whereas a two-month-old baby later required a shunt. The lateral ventricle-cystostomy and the third ventricle-cystostomy (according to the cyst extent) are the best endoscopic procedures, whereas the cyst fenestration through a suboccipital supracerebellar approach is no longer used. The rate of cured or improved patients after endoscopic surgery (14/16 or 87.5%) was rather similar to that of a group of twenty patients treated by traditional surgery (craniotomy and cyst excision and/or shunt) (85%). These data confirm that endoscopic fenestration of quadrigeminal cistern cysts must be performed as the first procedure because it is less invasive and avoids shunt dependency.

Arachnoid Cysts↗
PubMed2002

Predictors of outcome after the Fontan operation: is hypoplastic left heart syndrome still a risk factor?

OBJECTIVE: This study was undertaken to evaluate factors contributing to a decrease in early mortality and morbidity after the Fontan procedure between January 1, 1992, and December 31, 1999. METHODS: Outcomes evaluated were early survival, duration of pleural effusions, and duration of hospitalization. Potential predictors evaluated included anatomic diagnosis, presence of a common atrioventricular valve, preoperative pulmonary artery pressure, type of Fontan operation, type of intentional right-to-left shunt or baffle fenestration, and use of modified ultrafiltration. RESULTS: The modified Fontan procedure was performed in 332 patients at a median age of 22 months (range, 11-380 months) and a median weight of 11 kg (range, 5.8-120 kg). Prior stage I reconstructive surgery for classic or variant hypoplastic left heart syndrome had been performed in 205 (53%) of 332 patients, and 318 (96%) had undergone an interim superior cavopulmonary connection. A lateral-tunnel Fontan operation was performed in 281 patients, and an extracardiac conduit Fontan operation was performed in 51 patients. An intentional right-to-left shunt was created in 298 (90%) patients. Between 1992 and 1999, the outcome after the modified Fontan operation improved significantly. Overall mortality was 6.6% (22/332), with only 2 deaths since 1994. Morbidity was also reduced, with a decreased duration of pleural effusions and decreased hospital stay. In a multivariable analysis of the entire cohort, only the presence of a common atrioventricular valve (odds ratio, 7.64; 95% confidence limits, 2.07-28.14; P =.0002) and increased preoperative pulmonary artery pressure (odds ratio, 1.46/1 mm Hg increase; 95% confidence limits, 1.2-1.78; P <.001) increased the risk of early death, whereas use of a single-punch fenestration in a lateral-tunnel Fontan (odds ratio, 0.06; 95% confidence limits, 0.01-0.65; P =.02) and use of modified ultrafiltration (odds ratio, 0.14; 95% confidence limits, 0.03-0.72; P =.019) decreased the risk of death. The risk of prolonged pleural effusions (>3 days) was increased in patients with hypoplastic left heart syndrome (odds ratio, 1.73; 95% confidence limits, 1.07-2.81; P =.03) and was decreased by use of a single-punch fenestration in a lateral-tunnel Fontan operation (odds ratio, 0.17; 95% confidence limits, 0.07-0.4; P <.001), as well as by the use of modified ultrafiltration (odds ratio, 0.25; 95% confidence limits, 0.15-0.40; P <.01). CONCLUSIONS: In a contemporary series of Fontan operations performed largely in patients with hypoplastic left heart syndrome or variants, systemic ventricle morphology had no effect on mortality. Some patient characteristics, however, continue to influence outcome. The decrease in mortality and morbidity in the current era is attributed to changes in management strategies, specifically the use of modified ultrafiltration and baffle fenestration.

Cohort Studies↗
PubMed1996

Morphological changes of capillaries associated with muscle-fiber atrophy in the extensor digitorum longus muscle of aged rats.

We examined the structural changes of continuous capillaries in the extensor digitorum longus muscle of 6, 12 and 24-month-old normal rats. Capillaries around each muscle fiber in the sixth month were of the continuous type. In the 12th month, muscle fibers appeared almost normal except for widened intercellular spaces and degenerative changes in the subneural sarcoplasm. In the 24th month, many muscle fibers atrophied having greatly reduced diameter and irregular cross sectional profiles. Capillaries in the widened interstices, both in the 12th and 24th months, were embedded in an abundant amount of connective tissue components, including collagen fibrils and amorphous substances, and were surrounded by basal laminae arranged in concentric lamellae. Capillaries in the abundant connective tissues were mostly of the continuous type, while 10% in the 12th month and 20% in the 24th month consisted of endothelial cells with fenestrations bridged by a single-layered diaphragm. In some of the fenestrated capillaries in the 12th month, endothelial cells became partially disrupted and formed pores at the fenestrated portions. These findings confirm that intramuscular capillaries degenerate following the partial atrophy of muscle fibers, and suggest that the occurrence of fenestrations in the endothelial cells represent a first step in the degeneration of continuous capillaries.

Animals↗
PubMed1999

The effect of a right-to-left intracardiac shunt on the rate of rise of arterial and end-tidal halothane in children.

UNLABELLED: In this prospective study, we evaluated the effect of a right-to-left intracardiac shunt on the rate of rise of end-tidal and arterial halothane concentration in children. Six children aged 23-43 mo undergoing surgical closure of atrial fenestration after Fontan procedure were given 0.8% inspired halothane. End-tidal halothane was recorded at 1-min intervals after the introduction of halothane. Arterial halothane concentrations were determined 0, 1, 3, 5, 10, and 15 min after the introduction of halothane. The sampling was performed before and after closure of the atrial fenestration. The ratio of pulmonary to systemic blood flow (Qp/Qs) increased in this patient population, from 0.58 +/- 0.04 to 0.88 +/- 0.12 (P = 0.01). The rate of rise of end-tidal halothane did not change significantly with a decrease in the magnitude of the right-to-left intracardiac shunt after closure of the atrial fenestration. The ratio of arterial to inspired halothane concentrations at 1, 3, 5, 10, and 15 min were lower before closure of the atrial fenestration compared with after closure (P < 0.05). We conclude that the presence of a right-to-left intracardiac shunt significantly slows the rate of rise of arterial halothane in the face of a constant inspired concentration. The rate of rise of end-tidal halothane is not significantly affected in the presence of a right-to-left intracardiac shunt. IMPLICATIONS: In this prospective study, we found a slower rate of rise of halothane in arterial blood in children with right-to-left intracardiac shunting. Induction of anesthesia by inhalation of volatile anesthetics may therefore be slower in these children.

Anesthesia, General↗
PubMed1994

Failure of synthes anterior cervical fixation device by fracture of Morscher screws: a biomechanical study.

Anterior cervical fixation using the Synthes system has become increasingly popular. Two screw types for anchoring the plates include a "solid" titanium expansion screw and a plasma-sprayed fenestrated expansion screw that permits bony ingrowth. These screws were compared clinically and in the laboratory. In our first 20 cases using Synthes plates secured by Morscher fenestrated screws, 3 failures were observed, unilaterally in 1 patient and bilaterally in 2 others. In the unilateral screw failure, the contralateral screw was "solid" and did not fail. In the mechanical studies, screws were secured in the Synthes plate and embedded into methylmethacrylate and subjected to a sinusoidal bending moment to the mid-shaft of the screw. Load deflection data and cycles to failure were recorded. Fenestrated screws were found to demonstrate nearly twice as much deformation at failure and tolerated significantly fewer cycles to failure than did "solid" screws (p < 0.05). Because benefits of bony ingrowth into the screw are not well identified, the risks of fenestrated screw failure should preclude their routine use.

Adult↗
PubMed2000

Hearing preservation with labyrinthine ablation in otitis media.

OBJECTIVES: Iatrogenic fenestration of the inner ear in the presence of otitis media is commonly associated with permanent hearing loss. Hearing can generally be preserved when the vestibular labyrinth is ablated in a controlled manner in noninflamed ears. The purpose of this study was to examine the feasibility of hearing preservation with violation of the inner ear in the presence of middle ear inflammation. STUDY DESIGN: Prospective and controlled animal model. METHODS: Otitis media was induced bilaterally in pigmented guinea pigs with transtympanic injection of Streptococcus pneumoniae, nontypeable Haemophilus influenzae, or formalin-killed nontypeable H influenzae. Two to 4 days after injection, the horizontal canal of one ear was transected and sealed. Hearing was tested before and after labyrinthine ablation. RESULTS: Otitis media was induced in all ears. Bacterial cultures were positive in 19 of 20 S pneumoniae-injected ears, and in 10 of 16 nontypeable H influenzae-injected ears. One week after surgery, elevation of click thresholds (> 15 dB) was encountered in none of the fenestrated or unfenestrated S pneumoniae-infected ears, in two of six unfenestrated and three of six fenestrated nontypeable H influenzae-infected ears, and in one of five killed-nontypeable H influenzae-injected ears both with and without fenestration. CONCLUSIONS: These data suggest that ablation of a semicircular canal in the presence of middle ear inflammation or infection does not necessarily lead to profound sensorineural hearing loss. Hearing loss associated with iatrogenic violation of the semicircular canals may be more dependent on factors other than the presence of nonspecific middle ear inflammation.

Animals↗
PubMed2001

Value of constructive interference in steady-state three-dimensional, Fourier transformation magnetic resonance imaging for the neuroendoscopic treatment of hydrocephalus and intracranial cysts.

OBJECTIVE: To assess the value of constructive interference in steady-state, three-dimensional, Fourier transformation (CISS) magnetic resonance imaging in the endoscopic management of hydrocephalus and intracranial cysts. METHODS: CISS imaging and T2-weighted imaging were performed for 14 consecutive patients before and after fenestration procedures, using a flexible endoscope, to treat loculated or multiloculated hydrocephalus (4 patients), aqueductal stenosis or obstruction (4 patients), arachnoid cysts (4 patients), a cyst of the velum interpositum (1 patient), or an ependymal cyst (1 patient). Fifteen fenestration procedures were performed, including one reoperation. RESULTS: Preoperative CISS imaging demonstrated intracystic intraventricular septa not observed with conventional T2-weighted imaging for 11 of 15 procedures and provided better brain tissue/cerebrospinal fluid contrast, allowing better understanding of the cause of hydrocephalus and the nature of the cysts. CISS imaging and T2-weighted imaging were equally useful for monitoring postoperative changes in the sizes of ventricles or cysts and the presence of flow voids after third ventriculostomies. However, only CISS imaging clearly demonstrated the site of fenestration for six of the nine patients who underwent fenestration procedures. CONCLUSION: CISS imaging provides excellent cerebrospinal fluid/brain tissue contrast, allowing detailed study of the anatomic features of the ventricular system and cystic lesions. CISS imaging is valuable for both preoperative decision-making and postoperative evaluation.

Brain Diseases↗
PubMed2001

Three-dimensional analysis of syncytial-type cell plates during endosperm cellularization visualized by high resolution electron tomography.

The three-dimensional architecture of syncytial-type cell plates in the endosperm of Arabidopsis has been analyzed at approximately 6-nm resolution by means of dual-axis high-voltage electron tomography of high-pressure frozen/freeze-substituted samples. Mini-phragmoplasts consisting of microtubule clusters assemble between sister and nonsister nuclei. Most Golgi-derived vesicles appear connected to these microtubules by two molecules that resemble kinesin-like motor proteins. These vesicles fuse with each other to form hourglass-shaped intermediates, which become wide (approximately 45 nm in diameter) tubules, the building blocks of wide tubular networks. New mini-phragmoplasts also are generated de novo around the margins of expanding wide tubular networks, giving rise to new foci of cell plate growth, which later become integrated into the main cell plate. Spiral-shaped rings of the dynamin-like protein ADL1A constrict but do not fission the wide tubules at irregular intervals. These rings appear to maintain the tubular geometry of the network. The wide tubular network matures into a convoluted fenestrated sheet in a process that involves increases of 45 and 130% in relative membrane surface area and volume, respectively. The proportionally larger increase in volume appears to reflect callose synthesis. Upon fusion with the parental plasma membrane, the convoluted fenestrated sheet is transformed into a planar fenestrated sheet. This transformation involves clathrin-coated vesicles that reduce the relative membrane surface area and volume by approximately 70%. A ribosome-excluding matrix encompasses the cell plate membranes from the fusion of the first vesicles until the onset of the planar fenestrated sheet formation. We postulate that this matrix contains the molecules that mediate cell plate assembly.

Arabidopsis↗
PubMed1993

Blood-nerve barrier: ultrastructural and endothelial surface charge alterations following nerve crush.

Nerve crush results in an enhanced vascular permeability of the endoneurial vessels distal to the lesion. Vascular permeability at the blood-nerve barrier (BNB) to serum proteins is influenced by many factors, including anionic surface charge, endothelial vesicular transcytosis and the presence or absence of fenestrated vessels. Using mice and rats, the present ultrastructural investigation examined the effect of nerve crush (axonotmesis) on: (1) the distribution of endothelial anionic sites and (2) the appearance of fenestrations in endoneurial vessels after 4 and 14 day intervals as demonstrated with cationic probes. Transient anionic fenestrations developed in a minority of mouse endoneurial vessels in 4-day crushed nerves, but were not found in 14-day crushed nerves of mice nor in crushed nerves of rats. The known increase in the permeability of endoneurial vessels in rats and mice was not associated with reduced luminal labelling with cationic ferritin at physiological pH. At pH 2.0 the labelling of glycocalyx moieties (such as sialic acid) with cationic colloidal gold was disrupted in some epi- and endoneurial vessels of 4-day rats, but in a greater proportion after 14 days. The enhanced permeability of the BNB during degeneration and regeneration is related to the formation of anionic fenestrations in endoneurial vessels of mice and to the reduced and uneven distribution of endothelial glycocalyx moieties that are anionic at pH 2.0 in rats.

Animals↗
PubMed2000

True-lumen collapse in aortic dissection: part II. Evaluation of treatment methods in phantoms with pulsatile flow.

PURPOSE: To discover and evaluate the effective treatment methods to prevent or relieve true-lumen collapse in models of aortic dissection. MATERIALS AND METHODS: Two phantoms were built to simulate type B aortic dissection. After true-lumen collapse was induced, experiments were conducted to evaluate the effectiveness of clinically relevant variables in relieving the collapse. Variables included entry-tear size, branch-vessel flow distribution, distal reentry communication between the true and false limbs, aortic fenestrations, and pump output. To test the effect of closing the entry tear, a stent-graft was deployed over the entry tear under physiologic conditions in a mock-flow loop. The difference in the effect of each variable on the prevention and relief of true-lumen collapse was also investigated. RESULTS: It was more difficult to relieve true-lumen collapse than it was to prevent it. Placement of a stent-graft over the entry tear was the most effective method of relieving true-lumen collapse. Less-effective procedures included opening a false-lumen outflow branch and opening the distal reentry branch. Opening the fenestration-branch loops, meant to simulate the creation of artificial fenestrations in the intimal flap, did not relieve true-lumen collapse. CONCLUSION: The definitive treatment for true-lumen collapse in aortic dissection is direct repair of the entry tear to decrease false-lumen inflow. Otherwise, increasing the false-lumen outflow and/or creating distal fenestrations between the true and false lumina distal to the level of the compromised aortic branch are less-effective alternatives.

Aortic Dissection↗
PubMed2000

Interstitial flow through the internal elastic lamina affects shear stress on arterial smooth muscle cells.

Interstitial flow through the tunica media of an artery wall in the presence of the internal elastic lamina (IEL), which separates it from the subendothelial intima, has been studied numerically. A two-dimensional analysis applying the Brinkman model as the governing equation for the porous media flow field was performed. In the numerical simulation, the IEL was modeled as an impermeable barrier to water flux, except for the fenestral pores, which were uniformly distributed over the IEL. The tunica media was modeled as a heterogeneous medium composed of a periodic array of cylindrical smooth muscle cells (SMCs) embedded in a fiber matrix simulating the interstitial proteoglycan and collagen fibers. A series of calculations was conducted by varying the physical parameters describing the problem: the area fraction of the fenestral pore (0. 001-0.036), the diameter of the fenestral pore (0.4-4.0 microm), and the distance between the IEL and the nearest SMC (0.2-0.8 microm). The results indicate that the value of the average shear stress around the circumference of the SMC in the immediate vicinity of the fenestral pore could be as much as 100 times greater than that around an SMC in the fully developed interstitial flow region away from the IEL. These high shear stresses can affect SMC physiological function.

Arteries↗
PubMed1984

Microvascular architecture of the enamel organ in the rat-incisor maturation zone. Scanning and transmission electron microscopic studies.

In order to clarify the microvascular architecture and ultrastructural features of the capillary vessels related to transendothelial transport of metabolites, scanning electron microscopy of tissues digested by HCl-collagenase and of vascular corrosion casts as well as thin-section, tracer, and freeze-fracture replications were employed to study the maturation zone of rat-incisor enamel organ. The enamel-organ maturation zone was shown to have a well-developed, dense capillary plexus. The capillary vessels were distributed along furrows formed by the enamel-organ papillary ridges. In central regions they formed a regular, blindlike network; in the peripheral regions, however, they formed an irregular, circular network. Everywhere except in the nuclear and perinuclear regions, the very thin capillary-vessel endothelial walls were pierced with numerous fenestrations. Such fenestrations were evident in endothelial walls facing the ameloblast-layer site. In tracer experiments, intravenously injected horseradish peroxidase passed through the fenestrations in the endothelial walls to diffuse throughout the enamel-organ extracellular spaces. It did not, however, pass through intercellular spaces or transendothelial channels. The dense, regular distribution of highly fenestrated capillaries in the enamel organ is thought to make possible the rapid transcapillary exchange of various metabolites between the vascular system and the ameloblast and papillary layers that is necessary for enamel maturation.

Aging↗
PubMed1991

Capillary permeability and basolateral endocytic pathway of the epithelium in the mouse endolymphatic sac in vivo.

The capillary permeability and the basolateral endocytic pathway of the mouse endolymphatic sac (ES) epithelium were examined in vivo using intravenous injection of horseradish peroxidase (HRP). The capillaries of the ES were classified as either fenestrated or non-fenestrated. Because dense reaction products were observed soon after injection of HRP in macrophages near both types of capillaries, they were both considered to be permeable to macromolecules. In non-fenestrated capillaries, the basement membrane and small vesicles of the endothelium of the ES were stained with reaction product. These non-fenestrated capillaries were considered to be of muscle type. After 15 min, ES epithelial cells absorbed HRP basolaterally, and the multivesicular bodies and lysosomes of epithelial cells were stained with reaction product. The process of basolateral absorption in the ES epithelium was similar to that in the intestinal epithelium. Our results provide further evidence that the ES is a metabolically active organ which plays an important role in fluid transport in the inner ear.

Absorption↗
PubMed1995

Elastic lamina growth in the developing mouse aorta.

The growth and development of elastic laminae in the mouse aortic media were investigated by light and electron microscopic autoradiography after a single SC injection of L-[3,4-3H]-valine. Because of the remarkable stability of elastin, radiolabel incorporated into the elastic laminae during early stages of aortic development can be identified in the mature vessel. Light microscopic autoradiographs of aortae from mice injected with radiolabeled valine at 3, 14, or 21 days of postnatal age and sacrificed at 4 months of age showed silver grains evenly distributed around the circumference of the vessel, suggesting uniform elastic lamina growth. Electron microscopic autoradiographs of aortae from mice injected at 3 and 14 days' postnatal age and killed at 4 months of age showed the elastin initially deposited at 3 days to be in the center of the lamina, whereas the elastin deposited at 14 days remained peripherally located. These observations suggest that elastin deposited early in development does not undergo any significant redistribution during growth of the vessel. Because the aorta continues to increase in diameter after the elastic laminae are essentially complete, the fenestrations in the laminae were investigated as possible sites of further expansion of the laminae. In aortae from mice injected at 3 days and sacrificed at 4 days of postnatal age, the edges of the elastic lamina that border on fenestrations showed a large number of silver grains. Regions of the elastic lamina at some distance from the fenestration, however, appeared to be associated with fewer grains. Results from this study not only present unique observations of elastin deposition in developing elastic laminae but also provide evidence that the fenestrations in the elastic laminae may play a role in their continued expansion during later stages of aortic development.

Aging↗
PubMed2006

Orthogonal interlocking tandem clipping technique for the reconstruction of complex middle cerebral artery aneurysms.

OBJECTIVE: Complex aneurysms arising at the middle cerebral artery (MCA) bifurcation frequently present a microsurgical challenge to effectively obliterate while maintaining patency of the distal MCA branches. These aneurysms are often multilobed, with their long axis aligned with the long axis of the M1 trunk, placing the dome of the aneurysm in the surgeons' line of sight, preventing an unobstructed view of the entire bifurcation and proximal M1 segment. MCA aneurysms often have a broad neck, splaying the bifurcation. An orthogonal interlocking tandem clipping technique, maximizing the use of fenestrated aneurysm clips, is presented as a means to completely obliterate the aneurysm and simultaneously "reconstruct" the MCA bifurcation. CLINICAL PRESENTATIONS AND INTERVENTION: Fifteen complex MCA aneurysms were treated using an interlocking tandem clipping technique. In its simplest application, the blades of the initial aneurysm clip are incorporated into the fenestration of the second clip. Obliteration of the residual aneurysm is achieved with the blades of the second, fenestrated clip. RESULTS: Satisfactory aneurysm obliteration and reconstruction of the MCA bifurcation was achieved in all cases using this technique, with excellent neurological outcomes. CONCLUSION: Morphologically complex multilobed MCA aneurysms can be effectively clipped with "reconstruction" of the normal vascular anatomy using a tandem interlocking clipping technique. A fenestrated clip is used to incorporate the blades of the initial clip, while obliterating the remainder of the aneurysm.

Adult↗
PubMed2004

Novel intravascular ultrasound-guided method to create transintimal arterial communications: initial experience in peripheral occlusive disease and aortic dissection.

PURPOSE: To report our experience using a commercially available catheter-based system equipped with an intravascular ultrasound (IVUS) transducer to achieve controlled true lumen re-entry in patients undergoing subintimal angioplasty for chronic total occlusions (CTO) or aortic dissections. METHODS: During an 8-month period, 10 patients (6 men; mean age 73.4 years) with lower extremity (LE) ischemia from CTOs (n=7) or true lumen collapse from aortic dissections (n=3) were treated. Subintimal access and controlled re-entry of the CTOs were performed with a commercially available 6.2-F dual-lumen catheter, which contained an integrated 64-element phased-array IVUS transducer and a deployable 24-G needle through which a guidewire was passed once the target lumen was reached. The occluded segments were balloon dilated; self-expanding nitinol stents were deployed. In the aortic dissections, fenestrations were performed using the same device, with the IVUS unit acting as the guide. The fenestrations were balloon dilated and stented to support the true lumen. RESULTS: Time to effective re-entry ranged from 6 to 10 minutes (mean 7) in the CTOs; antegrade flow was restored in all 7 CTOs, and the patients were free of ischemic symptoms at up to 8-month follow-up. In the aortic dissection cases, the fenestrations equalized pressures between the lumens and restored flow into the compromised vessels. There were no complications related to the use of this device in any of the 10 patients. CONCLUSIONS: Our preliminary results demonstrate the feasibility of using this catheter-based system for subintimal recanalization with controlled re-entry in CTOs and for aortic flap fenestrations in aortic dissections. This approach can improve the technical success rate, reduce the time of the procedure, and minimize potential complications.

Aged↗