Rabih G. Tawk

Transforaminal lumbar interbody fusion: surgical technique and results in 24 patients.

OBJECTIVEThe advantage of anterior column support and fusion in addition to pedicle fixation in patients with degenerative spinal disorders has become increasingly clear. With the increase in popularity of this treatment, a variety of techniques have been used to achieve the goal of anterior column support, fusion, and segmental instrumentation. Posterior lumbar interbody fusion has been used since the late 1940s in the treatment of degenerative lumbar spine. We evaluated a modification to posterior lumbar interbody fusion called transforaminal lumbar interbody fusion (TLIF). METHODSA retrospective analysis was performed on 24 patients (9 women, 15 men) who underwent TLIF. The approach involved a unilateral laminectomy and inferior facetectomy at the level of fusion. The interbody fusion was achieved from this unilateral approach by performing discectomy, arthrodesis, and insertion of one or two titanium cages packed with autologous bone. The average age of the patients in this study was 42.6 ± 12.5 years. Five patients were smokers. Five cases were related to workmen’s compensation. Seventeen patients’ original symptoms were a combination of low back pain and radiculopathy. Ten patients had had a previous spine operation. RESULTSEleven patients had L4–S1 TLIFs. The rest of the patients had a single-level TLIF (L2–S1). Average intensive care unit and floor days were 1.1 ± 1.0 and 5.8 ± 2.2 days, respectively. The number of days to ambulation was 2.8 ± 1.6 days. There were a total of six self-limited complications in 24 patients (including one transient neurological complication). The average follow-up time was 16.9 ± 9.1 months. Twenty-two patients had solid fusions. A modified Prolo scale (4 worst, 20 best) was used to evaluate the clinical outcome. The average score was 16.1 ± 4.1. CONCLUSIONTLIF is a reliable and safe technique for interbody support that can be performed with excellent clinical outcome. In the authors’ experience, TLIF offers excellent exposure with minimal risk. This applies particularly in cases of repeat spine surgery, in which the presence of scar tissue makes traditional posterior lumbar interbody fusion techniques difficult or impossible. In addition, TLIF seems to be a viable alternative to anteroposterior circumferential fusion and/or anterior lumbar interbody fusion.

Trapping and revascularization for a dissecting aneurysm of the proximal posteroinferior cerebellar artery: Technical case report and review of the literature

OBJECTIVE AND IMPORTANCE Subarachnoid hemorrhage caused by an isolated dissection of the proximal portion of the posteroinferior cerebellar artery (PICA) is a rare problem. The optimal treatment to use for patients presenting with this clinical scenario varies and therefore is controversial in the literature. We report a patient in whom this problem was treated effectively with trapping of the diseased segment and revascularization of the PICA. We report this case to review this rare topic and to present our perspective on the indications for and the effectiveness of trapping and revascularization for proximal PICA dissections that cause hemorrhage. CLINICAL PRESENTATION A 55-year-old man was transferred to our institution and admitted for Hunt and Hess Grade IV subarachnoid hemorrhage, which improved to Hunt and Hess Grade III after ventricular drainage. Imaging revealed the source of the hemorrhage to be a pseudoaneurysm related to the dissection of the proximal portion of the PICA. INTERVENTION Three days after the initial bleeding episode, we operated on the patient. After the occipital artery was prepared for bypass, the diseased segment was trapped. The occipital artery-to-PICA anastomosis was then immediately performed distal to the trapped segment. CONCLUSION On the basis of our experience, the literature regarding this topic, and the anatomy of the perforators of the PICA, we think that the best treatment for a pseudoaneurysm located within the first three segments of the PICA is trapping of the diseased segment followed by revascularization distal to the trapped segment. This approach should prevent rehemorrhage and should avoid iatrogenic ischemic complications of the brainstem.

Feasibility and Safety of Pipeline Embolization Device in Patients With Ruptured Carotid Blister Aneurysms

BACKGROUND Treatment of internal carotid ruptured blister aneurysms (IC-RBA) presents many challenges to neurosurgeons because of the high propensity for rebleeding during intervention. The role of a Pipeline Embolization Device (PED) in the treatment of this challenging aneurysm subtype remains undefined despite theoretical advantages. OBJECTIVE To present a series of 11 patients treated with a PED and to discuss the management and results of this novel application of flow diverters. METHODS Medical records of patients who presented with IC-RBA from May 2011 to March 2013 were retrospectively reviewed at 6 institutions in the United States. All relevant data were independently compiled. RESULTS A total of 12 IC-RBAs in 11 patients were treated during the study period. Nine (75%) were treated with a single PED; 1 was treated with 2 PEDs; 1 was treated with coils and 1 PED; and 1 was treated with coils and 2 PEDs. Three (27%) had major perioperative complications: middle cerebral artery territory infarction, vision loss, and death. Seven patients demonstrated complete obliteration of the aneurysm in postoperative imaging. Early clinical outcomes were favorable (modified Rankin Scale score, 0-2) in all 10 survivors. CONCLUSION This study demonstrates the feasibility and safety of using the PED to treat IC-RBA with fair initial results. The proper introduction and management of antiplatelet regimen are key for successful results. Bleeding complications related to dual antiplatelet therapy were similar to those in previous studies of stent-assisted coiling for the same population. Larger cohort analysis is needed to define the precise role of flow diverters in the treatment of IC-RBA.

Solitaire flow restoration thrombectomy for acute ischemic stroke: Retrospective multicenter analysis of early postmarket experience after FDA approval

BACKGROUND The promising results of the Solitaire Flow Restoration (FR) With the Intention for Thrombectomy (SWIFT) trial recently led to Food and Drug Administration (FDA) approval of the Solitaire FR stent retriever device for recanalization of cerebral vessels in patients with acute ischemic stroke. OBJECTIVE To report the early postmarket experience with this device since its FDA approval in the United States, which has not been previously described. METHODS We conducted a retrospective analysis of consecutive acute ischemic strokes cases treated between March 2012 and July 2012 at 10 United States centers where the Solitaire FR was used as a single device or in conjunction with other intraarterial endovascular approaches. RESULTS A total of 101 patients were identified (mean age, 64.7 years; mean admission National Institutes of Health Stroke Scale [NIHSS] score, 17.6). Intravenous thrombolysis was administered in 39% of cases; other endovascular techniques were utilized in conjunction with the Solitaire FR in 52%. Successful recanalization (Thrombolysis in Myocardial Infarction 2/3) was achieved in 88%. The rate of symptomatic intracranial hemorrhage within the first 24 hours was 15%. In-hospital mortality was 26%. At 30 days, 38% of patients had favorable functional outcome (modified Rankin scale score ≤2). Severity of NIHSS score on admission was a strong predictor of poor outcome. CONCLUSION Our study shows that a variety of other endovascular approaches are used in conjunction with Solitaire FR in actual practice in the United States. Early postmarket results suggest that Solitaire FR is an effective tool for endovascular treatment of acute ischemic stroke.

Aneurysm Study of Pipeline in an Observational Registry (ASPIRe)

Background and Objective: Few prospective studies exist evaluating the safety and efficacy of the Pipeline Embolization Device (PED) in the treatment of intracranial aneurysms. The Aneurysm Study of Pipeline In an observational Registry (ASPIRe) study prospectively analyzed rates of complete aneurysm occlusion and neurologic adverse events following PED treatment of intracranial aneurysms. Materials and Methods: We performed a multicenter study prospectively evaluating patients with unruptured intracranial aneurysms treated with PED. Primary outcomes included (1) spontaneous rupture of the Pipeline-treated aneurysm; (2) spontaneous nonaneurysmal intracranial hemorrhage (ICH); (3) acute ischemic stroke; (4) parent artery stenosis, and (5) permanent cranial neuropathy. Secondary endpoints were (1) treatment success and (2) morbidity and mortality at the 6-month follow-up. Vascular imaging was evaluated at an independent core laboratory. Results: One hundred and ninety-one patients with 207 treated aneurysms were included in this registry. The mean aneurysm size was 14.5 ± 6.9 mm, and the median imaging follow-up was 7.8 months. Twenty-four aneurysms (11.6%) were small, 162 (78.3%) were large and 21 (10.1%) were giant. The median clinical follow-up time was 6.2 months. The neurological morbidity rate was 6.8% (13/191), and the neurological mortality rate was 1.6% (3/191). The combined neurological morbidity/mortality rate was 6.8% (13/191). The most common adverse events were ischemic stroke (4.7%, 9/191) and spontaneous ICH (3.7%, 7/191). The complete occlusion rate at the last follow-up was 74.8% (77/103). Conclusions: Our prospective postmarket study confirms that PED treatment of aneurysms in a heterogeneous patient population is safe with low rates of neurological morbidity and mortality. Patients with angiographic follow-up had complete occlusion rates of 75% at 8 months.

Isolated dissections and dissecting aneurysms of the posterior inferior cerebellar artery: topic and literature review.

Abstract Isolated dissections of the posterior inferior cerebellar artery (PICA) are rare. Thus, no large series of cases have been reported in the literature. Due to limited knowledge regarding the natural history of these lesions and the lack of high-quality evidence supporting various treatment options, management is controversial and practice parameters are ill defined. In order to offer a comprehensive reference for the diagnosis and management of isolated PICA dissections, the authors reviewed the National Library of Medicine from 1966 to October 2001. Twenty-seven patients averaging 43.6 years of age and including 14 males and 13 females were reported. Subarachnoid hemorrhage occurred in 20 patients, and two died. Dissections were located in the proximal PICA in 22 patients and were three times more common on the left side (left:right=3:1). Six patients were managed conservatively, and four with endovascular techniques. Seventeen had open surgery: five underwent resection, two went through trapping, and two had proximal clipping. Wrapping with muscle was performed in two patients, encasement with Sundt clips in two, and four had occipital artery (OA)-PICA bypass surgery. A meticulous analysis of reported cases with regard to clinical and pathological features, management strategies, and outcomes is presented.

Surgical decompression and coil removal for the recovery of vision after coiling and proximal occlusion of a clinoidal segment aneurysm : Technical case report

OBJECTIVE:We present the case of a patient with continued deterioration of vision after endovascular treatment of an unruptured clinoidal segment aneurysm. In conjunction with a review of the literature, the findings in this case highlight the need for further refinements in our understanding of pathophysiological changes induced by coiling of cerebral aneurysms, especially those in aneurysms producing signs and symptoms relating to mass effect. CLINICAL PRESENTATION:The patient is a 45-year-old man who presented with progressive vision loss. Imaging studies revealed a large, clinoidal segment aneurysm. The patient continued to experience progressive vision loss despite treatment with endovascular coiling, proximal occlusion, and high-dose steroid medication. INTERVENTION:The patient underwent a craniotomy for decompression of the optic nerve and for salvage of vision. Clipping of the distal vessel was performed, and the coil mass was removed. The patient experienced marked improvement of central vision after the surgical procedure. CONCLUSION:Although endovascular treatment of aneurysms protects most patients from aneurysm rupture, this case illustrates the fact that coiling, followed by proximal occlusion, might fail to alleviate symptoms related to mass effect. Our experience in this case suggests that early surgical decompression may be indicated for patients presenting with progressive visual deterioration.Received, September 8, 2005. Accepted, January 31, 2006. OBJECTIVE: We present the case of a patient with continued deterioration of vision after endovascular treatment of an unruptured clinoidal segment aneurysm. In conjunction with a review of the literature, the findings in this case highlight the need for further refinements in our understanding of pathophysiological changes induced by coiling of cerebral aneurysms, especially those in aneurysms producing signs and symptoms relating to mass effect. CLINICAL PRESENTATION: The patient is a 45-year-old man who presented with progressive vision loss. Imaging studies revealed a large, clinoidal segment aneurysm. The patient continued to experience progressive vision loss despite treatment with endovascular coiling, proximal occlusion, and high-dose steroid medication. INTERVENTION: The patient underwent a craniotomy for decompression of the optic nerve and for salvage of vision. Clipping of the distal vessel was performed, and the coil mass was removed. The patient experienced marked improvement of central vision after the surgical procedure. CONCLUSION: Although endovascular treatment of aneurysms protects most patients from aneurysm rupture, this case illustrates the fact that coiling, followed by proximal occlusion, might fail to alleviate symptoms related to mass effect. Our experience in this case suggests that early surgical decompression may be indicated for patients presenting with progressive visual deterioration.

Safety and efficacy of ticagrelor for neuroendovascular procedures. A single center initial experience

Introduction Although platelet response testing is controversial, up to one-third of neuroendovascular patients are ‘resistant’ to clopidogrel and are at risk for in stent thrombotic complications and may require alternative antiplatelet therapy. Ticagrelor is a new reversible ADP P2Y12 platelet receptor inhibitor with no known resistance. We describe the clinical experience with ticagrelor for neuroendovascular procedures as an alternative in clopidogrel P2Y12 platelet resistant patients. Methods We reviewed our cerebrovascular database for all patients who were non-responders to clopidogrel, defined as P2Y12% inhibition <30%, despite repeat clopidogrel loading dose of at least 600 mg, and who were then administered ticagrelor. Results 18 patients were non-responders to clopidogrel; 10 (56%) were men, eight (44%) were women, with a median age of 61 years (range 38–84). All patients received loading doses of at least 600 mg of clopidogrel and showed P2Y12 levels below 20% prior to ticagrelor administration. Patients were loaded with 180 mg of ticagrelor, and all but one patient showed an initial P2Y12 response above 60%. 11 patients underwent stenting, two underwent coiling, and five underwent treatment by pipeline embolization device. No patient experienced any adverse effects in the postoperative period related to the use of ticagrelor. Conclusions Ticagrelor offers an effective alternative to clopidogrel non-responders. All of our patients showed immediate platelet inhibition after a loading dose of 180 mg of ticagrelor, with no adverse effects. The cost of medication, patient compliance (twice a day doses), and reversible inhibition should be taken into consideration when using ticagrelor.

Use of the outreach distal access catheter as an intracranial platform facilitates coil embolization of select intracranial aneurysms: technical note.

Objective The Outreach distal access catheter (DAC; Concentric Medical, Mountain View, California, USA) has been designed to assist the Merci device (Concentric Medical) with clot retrieval in the setting of acute stroke. Its application for coil embolization of intracranial aneurysms was investigated. Methods Between December 2008 and January 2010, 150 aneurysms were treated with endovascular methods. In 18 cases of small aneurysms and/or increased parent vessel tortuosity, the DAC was used for additional support. Merits and complications related to the use of this catheter are reviewed. Results The mean aneurysm size was 7.1 mm (range 3.5–25). In each case, the DAC was used as an intracranial platform catheter in close proximity to the target aneurysm. This catheter (outer diameter 3.9 or 4.3 French) increased the stability and reduced the redundancy of the microcatheter. As a result, handling and control of the microcatheter were improved. In three cases, the coiling procedure could not be completed because of difficulties not related to the DAC. Aneurysms in the remaining patients were treated successfully with complete (n=12) or near complete (n=3) angiographic occlusion. Conclusion For smaller or distal intracranial aneurysms with difficult access, use of the DAC as an additional platform in close proximity to the target aneurysm subjectively enhanced microcatheter control and safety.

Endovascular Treatment of Ruptured Paraclinoid Aneurysms: Results, Complications, and Follow-Up

BACKGROUND AND PURPOSE: Paraclinoid aneurysms are an uncommon cause of aneurysmal SAH, and their treatment is challenging. To assess the effectiveness and safety of endovascular treatment of ruptured paraclinoid aneurysms, we performed a retrospective analysis of 33 patients. MATERIALS AND METHODS: Clinical and radiologic information on 33 patients undergoing endovascular therapy between 1999 and 2010 was retrospectively reviewed. Angiographic results were evaluated with the modified Raymond grading system, whereas clinical outcomes were evaluated with the mRS scale. RESULTS: Seventeen (52%) aneurysms were classified as clinoid segment aneurysms, and 16 (48%), as ophthalmic segment aneurysms. Twenty-six (79%) aneurysms were small, 6 (18%) were large, 1 was (3%) giant, and 39% were wide-neck. Coiling was done with balloon assistance in 36% of cases and stent-assistance in 6%. Technical complications occurred in 1 patient, contributing to death. Early clinical complications causing permanent disability occurred in 3% of cases. One patient (3%) had fatal rebleeding 18 days after treatment. Overall, procedure-related morbidity and mortality were, respectively, 3% and 6%. Complete occlusion of the aneurysm was achieved in 36% of patients after initial treatment and in 65% during follow-up (average, 29.3 months). Seven patients had recurrences requiring retreatment (30%). Clinical outcome (average, 32.9 months) was good in 75% of patients and poor in 25%. No delayed complications related to treatment and/or the aneurysm occurred. CONCLUSIONS: Ruptured paraclinoid aneurysms are challenging lesions from an endovascular and surgical point of view. Despite the high rate of recurrences, good clinical results and protection against rebleeding can be achieved with current endovascular techniques.