PubMed Health⌕ Search

Biomedical subjects

Pedro Lylyk

Publications and source records attributed to Pedro Lylyk.

17 recordsLinked to original sources

Moyamoya syndrome in an adolescent with essential thrombocythemia: successful intracranial carotid stent placement.

BACKGROUND: Essential thrombocythemia (ET) is a chronic myeloproliferative disorder with increased frequency of thrombotic events, including transient ischemic attacks (TIAs) and stroke. Moyamoya syndrome is a rare cerebrovascular disease characterized by progressive occlusion of intracerebral arteries with a typical "puff of smoke" angiographic pattern. We report the development of moyamoya syndrome in a patient with ET. CASE DESCRIPTION: The patient is an 18-year-old female who presented at age 13 with recurrent TIAs. Persistent thrombocytosis was found, a diagnosis of ET was made, and treatment with anagrelide was started. Despite normal platelet counts, she experienced recurrent TIAs and stroke. Severe stenosis of the supraclinoid segment of the left internal carotid artery (LICA) and abnormal collateral vessels were found, and moyamoya syndrome was diagnosed on the basis of the characteristic angiographic appearance. An intracranial stent was placed in the LICA, and since then, she has had an uneventful outcome after a 46-month follow-up. CONCLUSIONS: To our knowledge, the development of moyamoya phenomenon has not been reported in ET, and the relationship between these 2 disorders remains unclear. Besides, this is the first intracranial carotid stent implanted successfully in a patient with moyamoya.

Adolescent↗

Protected stent-assisted angioplasty in radiation-induced carotid artery stenosis.

OBJECTIVE: The surgical treatment of radiation-induced carotid stenosis is challenging and presents a high rate of complications. This has led several investigators to propose stent-assisted angioplasty as the treatment of choice for this condition. The aim of this study is to evaluate the potential risks of intra-procedural embolic stroke in this setting using cerebral protection devices. METHODS: We describe our recent experience in the endovascular treatment by means of stent-assisted angioplasty with the aid of a filter cerebral protection device of eight patients presenting with radiation-induced carotid stenosis. RESULTS: Procedural success, defined as residual stenosis of less than 30% was obtained in all cases. The mean percentage stenosis was reduced from mean 80+/-6.3% (range 70-90%) to 13+/-4% (range 10-20%). Predilation was performed in five cases, post-dilation in all the cases. Mild-to-moderate bradycardia while inflating the balloon was present in three cases and was severe in one case. No patient sustained myocardial infarction, stroke or TIA during the procedure or hospital stay. During a mean clinical follow-up of 16+/-7.3 months (range 5-25) there were no neurological events. On sonographic follow-up, no patient presented in-stent de novo stenosis. DISCUSSION: Carotid angioplasty with cerebral protection can be performed safely in radiation-induced carotid stenosis with a high technical success rate. With the recent innovations and improvements in angioplasty technique, its indications and results will have to be redefined. Given the complexity and complications of surgical approaches for this condition, and the encouraging results obtained with endovascular techniques, carotid angioplasty emerges as the preferred treatment option.

Adult↗

Stent-assisted arterial reconstruction of traumatic extracranial carotid dissections.

OBJECTIVES: Dissection of the internal carotid artery is a well-recognized complication of craniocervical trauma with potentially grave neurological outcome in patients with significant ischemic symptoms. Traditional anticoagulation therapy may not be applicable, since anticoagulation is contraindicated in multiple trauma or penetrating injuries. In these circumstances, rapid stenting followed by antiplatelet therapy may be performed. METHODS: Patients with angiographically proven traumatic carotid artery dissection were prospectively selected for endovascular stenting according to clinical and radiological criteria. Essentially, patients with hemodynamic significant hemispheric hypoperfusion (as indicated by angiography or perfusion MRI), or in whom anticoagulant therapy failed clinically, or anticoagulation was contraindicated, were considered at high risk for stroke and were selected for stenting. Twelve patients were selected for stenting. RESULTS: In seven patients, multiple stents were implanted. Endovascular treatment reduced mean dissection stenosis from mean 65+/-33% (range, 10-100%) to mean 7+/-9% (range, 20-0%). In a mean clinical follow-up of 11.5+/-6.3 months (range 3-24 months), eight patients improved and four remained stable, and none of the patients had a TIA or stroke. Doppler U/S studies did not detect any signs of de novo in-stent stenosis in any of the patients at a mean follow-up time of 9.2+/-6.4 months. CONCLUSIONS: In selected cases of traumatic dissections of the carotid artery, endovascular stent-assisted angioplasty may immediately restore the integrity of the vessel lumen, even of acutely occluded arteries. This approach efficiently prevented the occurrence of new ischemic events, without additional anticoagulation.

Adolescent↗

Endovascular reconstruction by means of stent placement in symptomatic intracranial atherosclerotic stenosis.

OBJECTIVE: Patients with intracranial atherosclerosis who fail antithrombotic therapy have a poor prognosis. The high rate of recurrent stroke warrants testing alternative treatments such as intracranial angioplasty. METHODS: We present our experience in the treatment of 104 patients (age range, 54-82 years; mean age, 67 years) with symptomatic intracranial atherosclerotic stenoses despite medical therapy who underwent stent-assisted angioplasty. Patient records were retrospectively analysed for location and degree of stenosis, regimen of antiplatelet agents, devices used, procedure-related complications and adverse events. Clinical (Modified Rankin Scale) and radiographic outcomes were obtained 24 hours, 1 month and 3-6 months after treatment. Sixty-five lesions (62.5%) were located in the posterior circulation. Mean stenosis was 75.4%. RESULTS: In all patients, the angiographic degree of stenosis was reduced to less than 30%. One stent was implanted in 66 patients (63%), and two or more in 38 patients (37%). Modified Rankin Scale (mR) was 1-2 in 67.5% of the cases, 3-4 in 25.9%, 5 in 2.8%, 6 in 3.8%. Procedural morbidity was 5.7% and procedural mortality was 3.8%. Angiographic follow-up was available in 58 patients (55.7%) and the restenosis rate was 12.5%. DISCUSSION: In selected patients, endovascular revascularization of intracranial arteries by means of stent-assisted angioplasty is technically feasible, effective and safe.

Aged↗

Partial aortic obstruction improves cerebral perfusion and clinical symptoms in patients with symptomatic vasospasm.

OBJECTIVE: Stroke studies in animals showed that aortic obstruction increases cerebral blood flow (CBF) and reduces infarct size. In this study we evaluate the safety and efficacy of a device providing partial and transitory aortic obstruction. METHODS: We report the results in 24 selected patients with symptomatic vasospasm by aneurysmal subarachnoid hemorrhage treated by partial and transitory aortic obstruction with a novel device (NeuroFlo, CoAxia, MN). Aneurysms were secured by coils prior to the procedure. We studied the adverse effects related to the aorta-obstructing device, and changes in CBF and neurological outcome. RESULTS: Mean flow velocity increased in both middle cerebral arteries over 15%, and the score in the National Institute of Health Stroke Scale decreased >or=2 point in 20 patients (83%). During the procedure, three patients developed symptoms that were controlled. At 30 days follow-up, three patients had 6 points (unrelated death), three had 3 points, six had 1 point, and 12 had 0 points, in the modified Rankin scale. DISCUSSION: Partial aortic obstruction was safe, the cerebral blood flow increased without inducing significant hypertension and the neurological defects improved in most of the patients. Efficacy with a better level of evidence will be determined by a randomized study.

Adult↗

Buenos Aires experience with the Neuroform self-expanding stent for the treatment of intracranial aneurysms.

OBJECT: The authors report their experience with the use of the Neuroform Microdelivery System for intravascular reconstruction. They assess the technical feasibility of the system, the efficacy of the combined application of stent and detachable coils, and the follow-up findings. METHODS: Fifty patients found to harbor a complex wide-necked intracranial aneurysm were selected for the study. Different strategies were chosen and the performance and technical success of the device were evaluated. Stent placement was recorded as optimal or suboptimal with respect to the stent position. Clinical and angiographic follow-up examinations were obtained. Forty-six patients with 48 intracranial aneurysms were treated, leading to a technical success rate of 92%. Forty-two lesions were located in the anterior circulation. In every case the dome/neck ratio was less than 2 and the mean aneurysm size in these patients was 8.8 mm. The most frequent clinical presentation was subarachnoid hemorrhage in 48% of cases. Stent placement was optimal in 81.2% of cases and suboptimal in 18.8%. In 31% of cases, the investigators encountered difficulties in placing the Neuroform stent. Clinical follow up was recorded in all patients and angiographic follow up was obtained in 63%. There were no cases of repeated hemorrhage. In a single case in which only the stent was implanted progressive thrombosis was identified during the follow-up period. The procedure-related morbidity and mortality rates were 8.6 and 2.1%, respectively. CONCLUSIONS: On the basis of the results, the authors conclude that the Neuroform self-expanding stent is a flexible and useful device that can be readily and safely maneuvered through tortuous intracranial vessels, enabling the endovascular treatment of complex wide-necked aneurysms. Early in the authors' experience, stent delivery presented difficulties; however, a second generation of devices has resolved this limitation. Although the early results are promising, the long-term benefit of this technique has to be proved by angiographic and clinical follow-up examinations.

Adult↗

Percutaneous vertebroplasty: technique and results in 192 procedures.

Percutaneous vertebroplasty with acrylic cement (usually polymethylmethacrylate) consists of injecting cement into vertebral bodies weakened by osseous lesions. The objective of this procedure is to obtain an analgesic effect by mechanical stabilization in destructive lesions of the spine. The three major indications are aggressive vertebral hemangiomas, severe or refractory pain related to osteoporotic vertebral fractures, and malignant vertebral tumors. Complications are infrequent, but occur essentially in patients with vertebral malignant tumors. We present our experience with 148 patients that underwent 192 percutaneous PMMA vertebroplasties for the treatment of painful osteoporotic compression fractures (76 patients, 105 vertebral levels), hemangiomas (31 patients, 43 vertebral levels) and neoplasms (31 patients, 43 vertebral levels). In a vast majority of appropriately selected cases and especially in osteoporotic cases, vertebroplasty constitutes a relatively simple procedure with a very high rate of success.

Adult↗

Carotid stent angioplasty: the role of cerebral protection devices.

Carotid endarterectomy has been validated with results of several randomized controlled trials in which its effectiveness has been demonstrated over that of the best nonsurgical therapy. However, in the past several years, carotid angioplasty with stent placement has emerged as a potential safe and effective alternative to carotid endarterectomy. In this article we examine the current status of carotid angioplasty with the recent introduction of innovative cerebral protection devices and improved endovascular devices. We present a brief description of the current randomized trials evaluating carotid endarterectomy compared to carotid angioplasty as well as our combined experience in 262 patients.

Angioplasty↗

Covered stent as an innovative tool for tumor devascularization and endovascular arterial reconstruction.

A temporal paraganglioma was pre-operatively embolised with particles and due to the fact that the internal carotid artery was encased by the tumor and that multiple petrous feeders precluded safe embolization, we decided to implant a balloon-expandable covered stent. On immediate post-procedural angiography, the arterial diameter was restored and a complete devascularization of the tumor was achieved. The tumor was operated with minimal blood loss and the carotid artery was released from surrounding tumor using the frame of the stent as a surgical limit. Covered stents may become a valuable tool for pre-operative tumor devascularization and arterial reconstruction especially when dealing with hypervascular tumors of the cranial base that encase the carotid artery.

Adult↗

Reconstructive endovascular approach for a cavernous aneurysm in infancy.

We report a unique case of endovascular arterial reconstruction using stent and coils in a symptomatic cavernous aneurysm presented in infancy. A 3-year-old infant presented with a partial cavernous sinus syndrome secondary to a bilobulate cavernous aneurysm with subarachnoid extension. Direct clipping represented a considerable challenge and trapping after bypass grafting was considered to risky. A combined endovascular approach using stent and coils was performed. A 4 x 18 mm balloon-expandable stent was then placed across the aneurysm orifice allowing the complete obliteration of the remnant with coils implanted through the stent mesh. Digital substraction angiography documented patency of the ICA lumen and complete obliteration of the aneurysm. A 24-months angiographic follow-up was performed confirming persistent aneurysm exclusion and patency of the parent vessel with no signs of in-stent de novo stenosis. Reconstructive endovascular technique using stent and coils allowed the treatment of a complex vascular condition. The cavernous lesion was excluded from the circulation while preserving normal flow through the parent vessel and its branches. Long-tern follow up is a major concern, specially in pediatric patients but the 24 months angiographic follow-up is encouraging.

Carotid Artery Diseases↗

Carotid artery stenting protected with an emboli containment system.

BACKGROUND AND PURPOSE: Fear of distal embolization and stroke has aroused concern regarding carotid stenting. Devices to protect the cerebral circulation may make carotid stenting safer. METHODS: A multidisciplinary study group tested a balloon occlusion-aspiration emboli entrapment device in conjunction with carotid stenting. The device consists of an elastomeric balloon on a steerable wire with a detachable adapter that inflates and deflates the distal temporary occlusion balloon. An aspiration catheter is used to remove trapped emboli after stenting and before occlusion balloon deflation. RESULTS: Seventy-five patients with severe internal carotid artery stenosis were treated with stents deployed with this cerebrovasculature protection system. All 75 patients (100%) had grossly visible particulate material aspirated, and all were treated successfully without major or minor stroke or death at 30 days. Preintervention stenosis was 81+/-10%, and residual stenosis was 5+/-7%. Nine patients (12%) had angiographic evidence of thrombus before intervention, but no patient had thrombus or vessel cutoff after the procedure. Four patients (5%) developed transient neurological symptoms during protection balloon occlusion, but symptoms resolved with balloon deflation. The 22 to 667 particles aspirated per patient ranged from 3.6 to 5262 microm in maximum diameter (mean, 203+/-256 microm). These particles included fibrous plaque debris, lipid or cholesterol vacuoles, and calcific plaque fragments. CONCLUSIONS: Protected carotid stenting was performed successfully and safely in this study early in the experience with cerebrovascular protection devices. Particulate emboli are frequent with stenting, and cerebral protection will likely be necessary to minimize stroke. Randomized trials comparing protected carotid stenting with endarterectomy are warranted.

Aged↗

Partially clipped intracranial aneurysm obliterated with combined stent and coil implantation.

PURPOSE: To report a case of endovascular stent placement to assist stable coil deployment in a symptomatic, wide-necked, partially clipped aneurysm. CASE REPORT: A 48-year-old woman presented for endovascular treatment of a symptomatic posterior communicating artery aneurysm remnant that was surgically clipped 10 years ago. A 3.5-mm x 12-mm balloon-expandable stent was placed across the aneurysm orifice followed by complete obliteration of the remnant with coils implanted through the stent mesh. Digital subtraction angiography documented continued patency of the arterial lumen and complete obliteration of the aneurysm at 11 months. CONCLUSIONS: Partial aneurysm clipping may assist or complicate secondary interventional procedures and interfere with correct visualization of the neck. Stent placement obviates the need for the balloon-assist method of coil embolization for wide-necked aneurysm remnants, acting as a mechanical barrier to hold the coils in a very unfavorable anatomy.

Angiography, Digital Subtraction↗

Endovascular reconstruction of intracranial arteries by stent placement and combined techniques.

OBJECT: The authors investigated the feasibility, safety, and short-term outcome of stent treatment for intracranial aneurysms, stenoses, and dissections. METHODS: One hundred twenty-three consecutive patients with intracranial saccular, dissecting, and fusiform aneurysms, atherosclerotic lesions, and dissections were selected for intracranial stent implantation with or without adjunctive coil placement. One hundred eleven patients (mean age 47 years, range 3-73 years) underwent stent treatment; 12 patients (9.8%) were not treated. These 111 patients were divided into four groups: in Group 1 there were 62 patients with saccular aneurysms; Group 2 included nine patients (10 lesions) with dissecting or fusiform aneurysms; in Group 3 there were 36 patients with symptomatic intracranial atheromatous stenoses of more than 50%; and Group 4 included four patients with symptomatic intracranial dissections. All patients underwent computerized tomography scanning and/or magnetic resonance imaging and cerebral digital subtraction angiography preoperatively. Of the 72 aneurysms in Groups 1 and 2, 59 (82%) were treated with combined endovascular stent implantation and endosaccular coil placement. In 67 aneurysms (93%) we achieved complete or nearly complete obliteration. All patients with arterial narrowing achieved residual stenoses of less than 30% postangioplasty. One patient required repeated angioplasty. The morbidity rate in the series was 10.9% and the mortality rate was 6.3%. CONCLUSIONS: These findings indicate that stent treatment is feasible and seems to be an effective modality for arterial reconstruction. This versatile tool allows the treatment of a wide variety of challenging intracranial lesions.

Adolescent↗

Angioplasty and stent placement in intracranial atherosclerotic stenoses and dissections.

BACKGROUND AND PURPOSE: Stent placement has been shown to increase the safety and effectiveness of balloon angioplasty in cervical carotid disease. Here, the authors investigated the feasibility, safety, and short-term outcome of stent-assisted angioplasty for the treatment of intracranial stenoses. METHODS: Thirty-four patients (age range, 12-77 years; mean age, 54 years) with symptomatic intracranial atherosclerotic lesions and dissections that produced stenosis of more than 50% were selected and treated with stents. Eighteen lesions (53%) were located in the anterior circulation, and 16 (47%) were in the vertebrobasilar complex. The mean stenosis was 75%. RESULTS: At follow up, 21 patients (62%) improved clinically, 11 (32%) remained stable, and the condition of two patients (6%) deteriorated. In all patients, the angiographic degree of stenosis was reduced to less than 30%. In 10 patients (29%), two or more stents were implanted: Two stents were implanted in six patients, and three, in four patients. The transient procedural morbidity rate was 12%, and the transient neurologic morbidity rate was 6%. One patient had hemorrhagic transformation due to reperfusion and died, and another patient had a massive myocardial infarction after 5 months. Twenty patients were followed up with angiography for at least 6 months, and none required repeat angioplasty. CONCLUSION: Endovascular revascularization of intracranial arteries by means of stent-assisted angioplasty is technically feasible, effective, and safe in selected patients.

Adolescent↗

From patient to model: stereolithographic modeling of the cerebral vasculature based on rotational angiography.

We developed a method to produce tubular in vitro models of the cerebral vessels from real patient data. Three-dimensional data sets obtained from patients undergoing rotational angiography were used for stereolithographic biomodeling by using rapid prototyping technology. In a second step, tubular reproductions of the cerebral vessels were obtained by using the lost-wax technique. These reproductions can be useful for hemodynamic research and for the development and preclinical evaluation of new endovascular treatment methods.

Blood Vessels↗