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Harry J Cloft

Publications and source records attributed to Harry J Cloft.

At least 19 recordsLinked to original sources
PubMed2006

Balloon-assisted coiling through a 5-French system.

INTRODUCTION: We present a catheter technique that utilizes a 5F system for the purpose of balloon-assisted coiling in the setting of intracranial aneurysms. METHODS: A standard 5F short sheath is placed in the common femoral artery, and a 5F diagnostic catheter is placed through the sheath and used for selective vessel angiography. When endovascular intervention is pursued, the diagnostic catheter is placed in the appropriate vessel and systemic heparinization is ensured. Over an exchange length wire, the 5F vertebral catheter and 5F short sheath are exchanged for a 5F Shuttle (Cook) sheath. We then routinely place a 10, 14 or 18 microcatheter over an appropriately gauged microguidewire into the aneurysm. As needed, balloon catheters are then placed across the neck of the aneurysm for remodeling purposes. During the course of the procedure, control angiography is performed through the Shuttle sheath. Following the placement of coils, the microcatheter and balloon catheter are removed and a final biplane image is obtained via the 5F Shuttle sheath. RESULTS: This technique has been employed in 15 patients who required balloon-assisted coiling of an intracranial aneurysm. There were no technical difficulties or arterial access site complications from the procedures. Catheter mobility and torque were not affected, nor was the quality of our imaging. CONCLUSION: We conclude that this small-diameter system provides ample "room" for catheter placement and interventional treatment while reducing the known risks of postprocedural complications. Angiographic images remain excellent and are comparable to those obtained by larger catheters.

Balloon Occlusion↗
PubMed2006

Endovascular treatment of experimental aneurysms by use of fibroblast-coated platinum coils: an angiographic and histopathologic study.

BACKGROUND AND PURPOSE: The purpose of this study was to determine whether implanting exogenous fibroblasts on platinum coils could enhance intra-aneurysmal fibrosis. Hypotheses included: (1) fibroblast-coated (FBC) platinum coils can improve angiographic results after embolization; and (2) FBC platinum coils can accelerate histological healing of embolized aneurysms. METHODS: Experimental aneurysms in rabbits were embolized with control platinum coils (n=18) or FBC coils (n=18). Subjects were euthanized at 14 days, 1 month, 3 months and 6 months after implantation. Digital subtraction angiography was used to evaluate stability after embolization. Histological samples were examined with a grading system (range, 0 to 12) based on neck and dome healing. RESULTS: Histology total scores and fibrosis ratio at 14 days were significantly greater in the FBC coil group compared with controls (6.6+/-1.9 versus 2.5+/-1.1, 1.2+/-0.6% versus 0.2+/-0.3%, respectively; P=0.0090). Cavities embolized with FBC coils showed cellular proliferation and thrombus organization, with an endothelialized membrane bridging the neck. There were no differences between groups in the later timepoints. The FBC coil group showed radiographic stability in 11 (61%) cases, coil compaction in 2 (11%) cases, and progressive occlusion in 5 (28%) cases. No progressive occlusion was seen in controls; 3 (17%) of 18 control cases exhibited coil compaction (P=0.0546). CONCLUSIONS: FBC coils can accelerate early histological healing compared with control coils in the rabbit aneurysm model.

Actins↗
PubMed2006

Modified technique to create morphologically reproducible elastase-induced aneurysms in rabbits.

INTRODUCTION: The purpose of this study was to create morphologically reproducible elastase-induced model aneurysms in rabbits. METHODS: We created 120 elastase-induced aneurysms in rabbits using two different methods: the standard technique (group 1, n=62) and a modified technique (group 2, n=58). In the standard technique a small cutdown with a focal area of exposure of the mid-right common carotid artery (RCCA) was employed, while in the modified technique the RCCA was completely exposed to its origin. We measured aneurysm sizes (neck diameter, width and height) in the two groups. The aneurysm sizes were compared between the two groups using Student's t test, and the standard deviations of the aneurysm sizes were compared between the groups using the F test. RESULTS: The mean aneurysm neck size, width and height in group 1 were 3.4+/-1.2 mm, 3.8+/-1.0 mm and 8.0+/-1.7 mm, respectively, and in group 2, were 3.2+/-0.9 mm, 3.7+/-0.6 mm and 9.1+/-1.8 mm, respectively. The differences in mean aneurysm neck and width between the two groups were not significant (P>0.05). However, there were significant differences in the standard deviation of these two parameters between the two groups (P<0.05 and P<0.01, respectively). The mean aneurysm height in group 2 was larger than in group 1 (P<0.001), but no significant difference in the standard deviation of this parameter between the two groups was found (P>0.05). CONCLUSION: The results indicate that more consistent aneurysm diameters can be created using the modified technique.

Animals↗
PubMed2006

Expanding the treatment window with mechanical thrombectomy in acute ischemic stroke.

INTRODUCTION: Acute ischemic stroke is a common disease associated with high mortality and significant long-term disability. Treatment options for acute ischemic stroke continue to evolve and include pharmaceutical and mechanical therapies. With the recent US Food and Drug Administration approval of a new device for mechanical thrombectomy, the options available for treatment of acute ischemic stroke have been expanded. Thrombolytic therapy is generally given intravenously in the first 3 h and up to 6 h via the intraarterial route for pharmacological clot disruption. The maximum time-frame for mechanical thrombectomy devices has yet to be determined. METHODS: A 78-year-old female presented to the emergency room with a dense right hemiparesis, leftward gaze preference and dense global aphasia. Eight hours after symptom onset, left carotid angiography confirmed a left internal carotid artery terminus occlusion. A single pass was made through the clot with an X6 Merci Retriever device. RESULTS: After a single pass, the vessel was reopened and normal flow in the left internal carotid artery was demonstrated. At the time of discharge, her neurological deficits had improved significantly. Furthermore, the final infarct area, as demonstrated on magnetic resonance imaging, was probably much smaller than it would have been if the vessel had not been recanalized. CONCLUSION: We report the use of a new mechanical thrombectomy device 8 h after onset of ischemic symptoms, with substantial subsequent improvement in neurological outcome. In selected cases, use of the Merci Retriever can result in improved outcomes beyond the traditional 6-h window used for intraarterial pharmacological thrombolysis.

Aged↗
PubMed2006

Use of the Perclose ProGlide device with the 9 French Merci retrieval system.

INTRODUCTION: Closure devices are commonly used in neurointerventional procedures to achieve groin hemostasis. These devices are particularly useful in procedures requiring anticoagulation and larger catheters. The suture-mediated Perclose ProGlide device is intended for use with 5F to 8F sheaths. We describe the use of the ProGlide device with 9F sheaths in acute stroke treatment using the Merci retrieval device. METHODS: The ProGlide device is advanced over a wire until the wire exit port is at the skin surface. The wire is removed and the device is advanced until pulsatile blood flow is encountered. The footplates are opened and the stitch is deployed. The footplates are then closed and the device is removed. After advancing the suture to the vessel, it is locked and trimmed. Firm pressure is necessary during deployment to prevent oozing around the device. If continued bleeding is encountered, direct manual pressure is used to achieve hemostasis. RESULTS: We have successfully used the Perclose ProGlide device in four patients following the Merci retriever without groin or extremity complication. The Perclose ProGlide device can be successfully used after placement of a 9F system in patients who have undergone mechanical thrombectomy. CONCLUSION: This technique may be of interest to endovascular surgical neuroradiologists because it affords fast hemostasis in large access sites following mechanical thrombectomy with the Merci retrieval device. Compared to the "Preclose" technique, it saves valuable time at the beginning of the case.

Aged, 80 and over↗
PubMed2006

Predictors of ischemic stroke in the territory of a symptomatic intracranial arterial stenosis.

BACKGROUND: Antithrombotic therapy for intracranial arterial stenosis was recently evaluated in the Warfarin versus Aspirin for Symptomatic Intracranial Disease (WASID) trial. A prespecified aim of WASID was to identify patients at highest risk for stroke in the territory of the stenotic artery who would be the target group for a subsequent trial comparing intracranial stenting with medical therapy. METHODS AND RESULTS: WASID was a randomized, double-blinded, multicenter trial involving 569 patients with transient ischemic attack or ischemic stroke due to 50% to 99% stenosis of a major intracranial artery. Median time from qualifying event to randomization was 17 days, and mean follow-up was 1.8 years. Multivariable Cox proportional hazards models were used to identify factors associated with subsequent ischemic stroke in the territory of the stenotic artery. Subsequent ischemic stroke occurred in 106 patients (19.0%); 77 (73%) of these strokes were in the territory of the stenotic artery. Risk of stroke in the territory of the stenotic artery was highest with severe stenosis > or =70% (hazard ratio 2.03; 95% confidence interval 1.29 to 3.22; P=0.0025) and in patients enrolled early (< or =17 days) after the qualifying event (hazard ratio 1.69; 95% confidence interval 1.06 to 2.72; P=0.028). Women were also at increased risk, although this was of borderline significance (hazard ratio 1.59; 95% confidence interval 1.00 to 2.55; P=0.051). Location of stenosis, type of qualifying event, and prior use of antithrombotic medications were not associated with increased risk. CONCLUSIONS: Among patients with symptomatic intracranial stenosis, the risk of subsequent stroke in the territory of the stenotic artery is greatest with stenosis > or =70%, after recent symptoms, and in women.

Aged↗
PubMed2006

Vascular anatomic variation in rabbits.

PURPOSE: To explore the vascular anatomic variation along the aortic arch in New Zealand White rabbits with the goal of highlighting potential anatomic configurations that might be encountered in the performance of preclinical endovascular research in rabbits. MATERIALS AND METHODS: Digital subtraction angiography images of the brachiocephalic artery (BCA) and aortic arch in New Zealand White rabbits were obtained after creation of elastase-induced aneurysms at the origin of the right common carotid artery (RCCA) in 214 animals. The patterns of origin of the RCCA and left common carotid artery (LCCA), right subclavian artery (RSCA) and left subclavian artery (LSCA), and right vertebral artery (RVA) and left vertebral artery (LVA) were analyzed. RESULTS: Five predominant variations of vessel origin were identified. In 200 of 214 cases (93%), the LCCA originated from the bifurcation of the BCA and aorta. In eight cases (4%), the LCCA directly originated from the aorta. In two cases (1%), the LCCA originated from the BCA. Aberrant RSCA anatomy in which the RSCA originated from the aortic arch instead of the BCA was found in three cases (1.5%). In a single case (0.5%), aberrant RSCA anatomy with the RVA originating from the BCA was encountered. CONCLUSIONS: Anatomic variation of the BCA in New Zealand White rabbits is similar to that seen in humans. Understanding of the normal and variant anatomy of the rabbit will aid investigators who use the rabbit model for endovascular research.

Angiography, Digital Subtraction↗
PubMed2005

Intra-venous digital subtraction angiography: an alternative method to intra-arterial digital subtraction angiography for experimental aneurysm imaging.

Conventional intra-arterial digital subtraction angiography (IADSA), which necessitates surgical exposure and ligation of the femoral artery, is an invasive and expensive method of evaluation for experimental elastase-induced aneurysms in rabbits. The purpose of this study was to examine and validate intra-venous digital subtraction angiography (IVDSA) as an alternative to IADSA by comparing their diagnostic accuracies. We performed both IVDSA and IADSA for 24 elastase-induced saccular aneurysms in a rabbit model, 1 month following creation. Aneurysm sizes (neck, width and height) from both the IVDSA and IADSA procedures were evaluated and measured. Comparison of the aneurysm sizes between IVDSA and IADSA were performed with the Wilcoxon paired signed-rank test. All the aneurysms were seen clearly in both the IVDSA and IADSA techniques. Mean sizes of the IVDSA aneurysm neck, width and height were 3.41 +/- 0.80 mm, 3.61 +/- 0.93 mm and 8.07 +/- 2.11 mm, respectively. Mean sizes of the IADSA aneurysm neck, width and height were 3.43 +/- 0.80 mm, 3.66 +/- 0.92 mm and 8.16 +/- 2.25 mm, respectively. No significant difference was found in the sizes of the aneurysm neck, width and height between the two groups (P = 0.311, P = 0.086 and P = 0.258, respectively). IVDSA appears to be an alternative method for evaluating elastase-induced aneurysms in rabbits.

Angiography, Digital Subtraction↗
PubMed2005

Natural history, evaluation, and management of intracranial vascular malformations.

Intracranial vascular malformations are seen increasingly in clinical practice, primarily because of advances in cross-sectional brain and spinal cord imaging. Commonly encountered lesion types include arteriovenous malformations, cavernous malformations, venous malformations, dural arteriovenous fistulas, and capillary telangiectasias. Patients can experience various symptoms and signs at presentation. The natural history of vascular malformations depends on lesion type, location, size, and overall hemodynamics. The natural history for each lesion subtype is reviewed, with special consideration of the risk of hemorrhage or other adverse outcomes after the lesion is detected and any known predictors of hemorrhage or other outcomes. In practice, these data are compared with the risk of available treatment options as the optimal management is clarified. A multidisciplinary approach including neurosurgery, radiosurgery, interventional neuroradiology, and vascular neurology is most useful in determining the best management strategy.

Arteriovenous Fistula↗
PubMed2005

Angiographic and histologic analysis of experimental aneurysms embolized with platinum coils, Matrix, and HydroCoil.

BACKGROUND AND PURPOSE: A report directly comparing platinum coils, Matrix coils, and HydroCoils in a single animal model does not currently exist. We evaluated and compared the performance of these three products in the embolization of experimental aneurysms. METHODS: Thirty-three elastase-induced saccular aneurysms were created in rabbits. Aneurysms were embolized with Matrix coils (n = 15), HydroCoils (n = 9), or platinum coils (n = 9). The groups were compared with respect to the following parameters: aneurysm size, procedure duration, number and total length of devices deposited, angiographic occlusion score, and volumetric occlusion percentage. Follow-up angiographic and histologic features at 2, 6, and 10 weeks after embolization were analyzed. Groups were compared by using analysis of variance and chi2 tests. RESULTS: No significant differences were found among groups regarding aneurysm size, total device length, initial angiographic occlusion score, or procedure time. The mean number of devices for Matrix subjects was less than that for platinum coils (P = .02) and HydroCoil (P = .03). Volumetric occlusion for HydroCoil (76%) was significantly greater (P < .0001) than both platinum coils (31%) and Matrix (23%). Angiographic durability was significantly increased in the HydroCoil group compared with Matrix (P = .03). Coil compaction was found more frequently in the Matrix group (five cases, 33%) than the HydroCoil (no cases, 0%), or platinum coil groups (two cases, 22%). The Matrix group showed greater tissue reaction compared with platinum coils (P < .05). CONCLUSION: In the rabbit model, the use of HydroCoils results in improved long-term occlusion rates compared with Matrix and platinum coils. The Matrix group showed an increase in inflammation and coil compaction compared with HydroCoils and platinum coils.

Animals↗
PubMed2005

3D cerebral angiography: radiation dose comparison with digital subtraction angiography.

BACKGROUND AND PURPOSE: As the use of 3D rotational angiography (3D RA) for the evaluation of cerebral vasculature becomes more widespread, it is important to evaluate this imaging method's effect on patient radiation dose. The purpose of the study is to measure 3D RA radiation dose as compared with biplanar digital subtraction angiography (DSA). METHODS: The distribution and peak skin dose were measured for 3D RA and biplanar DSA by using an anthropomorphic skull phantom. In addition, the cumulative incident dose, summed over all images in each acquisition, was determined. Measurements were acquired for our facility's standard 3D RA acquisition mode (25 degrees /s rotational speed; 162 total frames) and other available acquisition mode selections. RESULTS: For 3D RA, the skin dose was found to be distributed across the back and sides of the skull with the peak skin dose located at the center of the back of the skull. The peak skin dose for the standard 3D RA acquisition mode was 15 mGy. For a biplanar DSA run, the peak skin dose was 58 mGy, also located at the back of the skull. The cumulative incident dose for the standard 3D RA acquisition mode was 33 mGy, compared with 53 mGy for biplanar DSA. CONCLUSION: The patient radiation dose for 3D RA is significantly lower than for biplanar DSA, by nearly a factor of 4 in peak skin dose and 40% lower in cumulative incident dose.

Angiography, Digital Subtraction↗
PubMed2005

Modified histologic technique for processing metallic coil-bearing tissue.

We developed a modified paraffin-embedding histologic technique for processing metallic coil-bearing aneurysm tissues. This modified technique was successfully employed for processing platinum coil-bearing tissue for 30 rabbit aneurysms and 6 swine aneurysms. This technique for sectioning coil-bearing aneurysms resulted in little or no tissue distortion and permitted good preservation of morphology and application of multiple advanced staining techniques. This technique is considered beneficial for studying the molecular mechanisms of aneurysm healing after coiling.

Animals↗
PubMed2005

Can neck size in elastase-induced aneurysms be controlled? A prospective study.

BACKGROUND AND PURPOSE: An earlier retrospective study indicated that the neck size of elastase-induced aneurysms could be controlled by adjusting the position of the inflated balloon. We report the current prospective study to confirm our previous work. METHODS: Ninety elastase-induced aneurysms were created in rabbits. Group 1 (n = 62) included cases in which the occlusion balloon resided low, completely within the brachiocephalic/subclavian arteries. Group 2 (n = 28) included cases in which the balloon resided high, within both the common carotid artery and brachiocephalic/subclavian arteries. Follow-up digital subtraction angiography was performed. The aneurysm sizes were measured and compared between groups. The Student t test and the Fisher exact test were used for statistical analysis. RESULTS: The mean aneurysm neck diameter and width for group 1 was significantly larger than that of group 2 (3.4 +/- 1.2 and 2.3 +/- 0.9 mm, P < .001; 3.8 +/- 1.0 and 3.3 +/- 0.9 mm, P < .05, respectively). The proportion of wide-necked aneurysms in group 1 was significantly larger than that in group 2 (29% vs 4%; P < .005). Mean dome-to-neck ratios were 1.2 +/- 0.4 and 1.7 +/- 0.7 for groups 1 and 2 (P < .005). There was no significant difference in aneurysm height between groups 1 and 2 (8.0 +/- 1.7 and 7.5 +/- 2.2 mm; P > .05). CONCLUSION: The neck size of elastase-induced aneurysm models in rabbits can be controlled by adjusting the position of the inflated balloon.

Angiography, Digital Subtraction↗
PubMed2004

Cost of treating high-risk symptomatic carotid artery stenosis: stent insertion and angioplasty compared with endarterectomy.

OBJECT: Definitive data characterizing the safety and efficacy of carotid angioplasty with stent placement (CAS) for symptomatic, occlusive carotid artery (CA) disease require further refinements and standardization of techniques as well as large prospective studies on a par with the North American Symptomatic Carotid Endarterectomy Trial (NASCET). Despite the absence of such data, many surgeons have performed angioplasty and stent placement in patients with clinical or anatomical features known to add significant perioperative risk and capable of disqualifying the patients from participation in NASCET: There exists no cost analysis comparing high-risk endarterectomy with percutaneous angioplasty and stent insertion. METHODS: Forty-five patients (29 men and 16 women) with high-risk, symptomatic CA stenosis have been treated with CAS at the authors' institution since 1996. Indications for this procedure included symptomatic recurrent stenosis following CA endarterectomy (CEA), active coronary disease, high CA bifurcation, and severe medical comorbidities. A longstanding CEA computer database was screened for control patients with similar risk factors; 391 patients (276 men and 115 women) were identified. Actual cost data, duration of hospital stay, and relevant clinical data from the time of treatment until hospital discharge were collected in each patient. The median total cost of CAS was dollar 10,628, whereas that for CEA was dollar 10,148 (p = 0.495). CONCLUSIONS: In patients with high-risk, NASCET-ineligible CA stenosis there was no overall statistically significant cost difference between CEA and CAS. Given that there may not be a cost advantage for either procedure, procedural risk, efficacy, and durability should be key factors in determining the optimal treatment strategy.

Aged↗