Drug Administration Investigational Device Exemption Research Articles

SF-36 PCS Benefit-Cost Ratio of Lumbar Fusion Comparison to Other Surgical Interventions

A retrospective review of prospectively collected data. To review systematically the SF-36 PCS outcomes of a large data set, including several randomized clinical trials for lumbar spine fusion at 1 and 2 years after surgery. We also present for comparison a review of typical changes in SF-36 PCS in other surgical interventions (total knee replacement, total hip replacement, and coronary artery bypass surgery) to define the average reimbursement costs per PCS improvement with each of these interventions. Data from 11 prospective multicenter studies (9 Food and Drug Administration Investigational Device Exemption, Randomized Prospective Clinical Trials, class 1 data) accounted for the lumbar spine fusion group (n = 1826). Data for total knee replacement, total hip replacement, and coronary artery bypass surgery were obtained from a comprehensive review of the literature. Comparisons of SF-36 PCS improvements were made at defined postoperative time points and with published study findings of other medical conditions. Reimbursement estimates (not including estimated physician and rehabilitation fees) for each surgical intervention were based on Centers for Medicare and Medicaid Services Medicare Provider Analysis and Review and All Payer Data (2002). Cost estimates were calculated for a minimal clinical important improvement (reimbursement dollars/mean PCS change *5.42 point PCS improvement). SF-36 PCS significantly improved at both 1 and 2 years following lumbar spine fusion surgery (P < 0.0001), and was comparable to the control surgical outcomes. With the use of data from Centers for Medicare and Medicaid Services Medicare Provider Analysis and Review and All Payer Data, hospital reimbursement averaged $15.2-18.2K for lumbar spine fusion, $9.8-11.3K for total knee replacement, $9.6-11.3K for total hip replacement, and $9.8-11.3K for coronary artery bypass surgery. Calculations of reimbursement dollars to elicit minimum clinically important change in PCS of 5.42 points following surgery ranged from $6.1 to $7.3K for lumbar spine fusion, $5.7 to $6.6K for total knee arthroplasty, $3.9 to $4.5K for total hip replacement, and $18.2 to $22.5K for coronary artery bypass surgery. While the exact numbers may vary for each treatment based on the population studied and the cost estimates used, lumbar fusion cost per benefit achieved was very comparable to other well-accepted medical interventions (total hip replacement, total knee replacement, and coronary artery bypass surgery).

Results of the Prospective, Randomized, Multicenter Food and Drug Administration Investigational Device Exemption Study of the ProDisc®-L Total Disc Replacement Versus Circumferential Fusion for the Treatment of 1-Level Degenerative Disc Disease

A prospective, randomized, multicenter, Food and Drug Administration-regulated Investigational Device Exemption clinical trial. To evaluate the safety and effectiveness of the ProDisc-L (Synthes Spine, West Chester, PA) lumbar total disc replacement compared to circumferential spinal fusion for the treatment of discogenic pain at 1 vertebral level between L3 and S1. As part of the Investigational Device Exemption clinical trial, favorable single center results of lumbar total disc replacement with the ProDisc-L have been reported previously. Two hundred eighty-six (286) patients were treated on protocol. Patients were evaluated before and after surgery, at 6 weeks, 3, 6, 12, 18, and 24 months. Evaluation at each visit included patient self-assessments, physical and neurologic examinations, and radiographic evaluation. Safety of ProDisc-L implantation was demonstrated with 0% major complications. At 24 months, 91.8% of investigational and 84.5% of control patients reported improvement in the Oswestry Low Back Pain Disability Questionnaire (Oswestry Disability Index [ODI]) from preoperative levels, and 77.2% of investigational and 64.8% of control patients met the > or =15% Oswestry Disability Index improvement criteria. Overall neurologic success in the investigational group was superior to the control group (91.2% investigational and 81.4% control; P = 0.0341). At 6 weeks and 3 months follow-up time points, the ProDisc-L patients recorded SF-36 Health Survey scores significantly higher than the control group (P = 0.018, P = 0.0036, respectively). The visual analog scale pain assessment showed statistically significant improvement from preoperative levels regardless of treatment (P < 0.0001). Visual analog scale patient satisfaction at 24 months showed a statistically significant difference favoring investigational patients over the control group (P = 0.015). Radiographic range of motion was maintained within a normal functional range in 93.7% of investigational patients and averaged 7.7 degrees. ProDisc-L has been found to be safe and efficacious. In properly chosen patients, ProDisc-L has been shown to be superior to circumferential fusion by multiple clinical criteria.

Complications of Lumbar Artificial Disc Replacement Compared to Fusion: Results From the Prospective, Randomized, Multicenter US Food and Drug Administration Investigational Device Exemption Study of the Charité Artificial Disc

Background Previous reports of lumbar total disc replacement (TDR) have described significant complications. The US Food and Drug Administration (FDA) investigational device exemption (IDE) study of the Charité artificial disc represents the first level I data comparison of TDR to fusion. Methods In the prospective, randomized, multicenter IDE study, patients were randomized in a 2:1 ratio, with 205 patients in the Charité group and 99 patients in the control group (anterior lumbar interbody fusion [ALIF] with BAK cages). Inclusion criteria included confirmed single-level degenerative disc disease at L4-5 or L5-S1 and failure of nonoperative treatment for at least 6 months. Complications were reported throughout the study. Results The rate of approach-related complications was 9.8% in the investigational group and 10.1% in the control group. The rate of major neurological complications was similar between the 2 groups (investigational = 4.4%, control = 4.0%). There was a higher rate of superficial wound infection in the investigational group but no deep wound infections in either group. Pseudarthrosis occurred in 9.1% of control group patients. The rate of subsidence in the investigational group was 3.4%. The reoperation rate was 5.4% in the investigational group and 9.1% in the control group. Conclusions The incidence of perioperative and postoperative complications for lumbar TDR was similar to that of ALIF. Vigilance is necessary with respect to patient indications, training, and correct surgical technique to maintain TDR complications at the levels experienced in the IDE study.

Comparison of LionHeart LVAD-Implanted Calves Based on Renal Infarctions

Calves implanted with the LionHeart left ventricular assist device during the Food and Drug Administration Investigational Device Exemption (IDE) trial had fewer renal infarctions than calves implanted after this trial (post-IDE). Since a decrease in renal infarctions indicates a favorable outcome, we compared nine IDE with 16 post-IDE implantations. Renal infarct severity was graded (0 to 4) on the basis of necropsy reports, histopathology reports, and photographs. Implants were compared for duration of support, anticoagulation, device flow, percent fill, device rate, free plasma hemoglobin, fibrinogen, platelet count, nonsteroidal anti-inflammatory drug use, inlet cannula shape, and outlet graft-to-graft anastomosis technique. IDE calves had lower renal pathology scores (1.8 vs. 2.8, p = 0.03), mean device percent fill (88.5% vs. 94.0%, p = 1 x 10), and median free plasma hemoglobin (2.6 vs. 4.4 mg/dL, p = 0.01). IDE animals also had a higher mean device rate (108 vs. 98 bpm, p = 0.04), received low-molecular-weight dextran in the early postoperative period, began oral warfarin earlier, had straighter inlet cannulae, and had factory-sewn outlet graft-to-graft anastomoses. Duration of support did not predict severity of renal infarction, and there were no differences in device flow, international normalized ratio, platelet count, or nonsteroidal anti-inflammatory drug use. These results could assist future implantations.

Complications of Lumbar Artificial Disc Replacement Compared to Fusion: Results From the Prospective, Randomized, Multicenter US Food and Drug Administration Investigational Device Exemption Study of the Charité Artificial Disc.

BackgroundPrevious reports of lumbar total disc replacement (TDR) have described significant complications. The US Food and Drug Administration (FDA) investigational device exemption (IDE) study of the Charité artificial disc represents the first level I data comparison of TDR to fusion.MethodsIn the prospective, randomized, multicenter IDE study, patients were randomized in a 2:1 ratio, with 205 patients in the Charité group and 99 patients in the control group (anterior lumbar interbody fusion [ALIF] with BAK cages). Inclusion criteria included confirmed single-level degenerative disc disease at L4-5 or L5-S1 and failure of nonoperative treatment for at least 6 months. Complications were reported throughout the study.ResultsThe rate of approach-related complications was 9.8% in the investigational group and 10.1% in the control group. The rate of major neurological complications was similar between the 2 groups (investigational = 4.4%, control = 4.0%). There was a higher rate of superficial wound infection in the investigational group but no deep wound infections in either group. Pseudarthrosis occurred in 9.1% of control group patients. The rate of subsidence in the investigational group was 3.4%. The reoperation rate was 5.4% in the investigational group and 9.1% in the control group.ConclusionsThe incidence of perioperative and postoperative complications for lumbar TDR was similar to that of ALIF. Vigilance is necessary with respect to patient indications, training, and correct surgical technique to maintain TDR complications at the levels experienced in the IDE study.

Magnetic Mini-Mover Procedure for pectus excavatum: I. Development, design, and simulations for feasibility and safety

Background/Purpose Correction of pectus excavatum (PE) results in measurable improvement in lung capacity and cardiac performance as well as improved appearance and self-image. The Nuss and modified Ravitch approaches attempt to correct the chest wall deformity by forcing the sternum forward in 1 step and holding it in place using a metal strut. The initial operation requires extensive manipulation under general anesthesia and results in postoperative pain, requiring hospitalization and regional anesthesia. Pain and disability may last for weeks. Both procedures are expensive. A better principle would be a gradual bit-by-bit repair via small increments of pressure applied over many months. We developed the Magnetic Mini-Mover Procedure and applied this strategy to correct PE. Methods The Magnetic Mini-Mover Procedure uses magnetic force to pull the sternum forward. An internal magnet implanted on the sternum and an external magnet in a nonobtrusive custom-fitted anterior chest wall orthosis produce an adjustable outward force on the sternum. Outward force is maintained until the abnormal costal cartilages are remodeled and the pectus deformity is corrected. Results We implanted a magnet in human skeletons and measured the force applied to the sternum when the distance between the internal and external magnets was varied in increments. With the 2 magnets 1 cm apart, the outward force was adequate to move the sternum at least 1 cm. We also mapped the magentic field in the two-magnet configuration and found that maximum field strengths at the surface of the heart and at the outer surface of the orthosis were at safe levels. Conclusions The Magnetic Mini-Mover Procedure allows correction of PE by applying magnetic force over a period of months. Crucial questions raised during our design, redesign, and simulation testing have been satisfactorily answered, and we have received a Food and Drug Administration Investigation Device Exemption (G050196/A002) to proceed with a phase I to II clinical trial.

Clinical outcomes of the Dynesys dynamic neutralization system: 1-year preliminary results

In this study the authors present the preliminary clinical outcomes of dynamic stabilization with the Dynesys spinal system as part of a multicenter randomized prospective Food and Drug Administration (FDA) investigational device exemption (IDE) clinical trial. This study included 101 patients from six IDE sites (no participants were omitted from the analysis) who underwent dynamic stabilization of the lumbar spine with the Dynesys construct. Patient participation was based on the presence of degenerative spondylolisthesis or retrolisthesis (Grade I), lateral or central spinal stenosis, and their physician's determination that the patient required decompression and instrumented fusion for one or two contiguous spinal levels between L-1 and S-1. Participants were evaluated preoperatively, postoperatively at 3 weeks, and then at 3-, 6-, and 12-month intervals. The 100-mm visual analog scale was used to score both lower-limb and back pain. Patient functioning was evaluated using the Oswestry Disability Index (ODI), and the participants' general health was assessed using the Short Form-12 questionnaire. Overall patient satisfaction was also reported. One hundred one patients (53 women and 48 men) with a mean age of 56.3 years (range 27-79 years) were included. The mean pain and function scores improved significantly from the baseline to 12-month follow-up evaluation, as follows: leg pain improved from 80.3 to 25.5, back pain from 54 to 29.4, and ODI score from 55.6 to 26.3%. The early clinical outcomes of treatment with Dynesys are promising, with lessening of pain and disability found at follow-up review. Dynesys may be preferable to fusion for surgical treatment of degenerative spondylolisthesis and stenosis because it decreases back and leg pain while avoiding the relatively greater tissue destruction and the morbidity of donor site problems encountered in fusion. However, long-term follow-up care is still recommended.

Evaluation of Surgical Volume and the Early Experience With Lumbar Total Disc Replacement as Part of the Investigational Device Exemption Study of the Charité Artificial Disc

A prospective, randomized, multicenter, Food and Drug Administration regulated Investigational Device Exemption (IDE) clinical trial. To discern whether there is a correlation between surgical volume and clinical outcomes, as well as the complication rate and perioperative data points, for lumbar total disc replacement. To examine the early experience for lumbar total disc replacement as part of an IDE study. To our knowledge, an analysis of the effect of surgical volume has not been performed for any spine surgical procedure. Prior reports of the early experience with lumbar total disc replacement consist of retrospective reviews with nonspecific indications. An analysis was performed of the Food and Drug Administration IDE Study of the Charité Artificial Disc (DePuy Spine, Inc., Raynham, MA). Patients enrolled in the control group were omitted from the analysis. Up to 5 nonrandomized cases (representing the early experience) were performed at each site before beginning the randomized arm of the study. There were 3 comparisons performed: nonrandomized cases (71) versus randomized cases (205); randomized cases performed by high-enrolling surgeons versus low-enrolling surgeons; and randomized cases at high-volume institutions versus low-volume institutions. The high-enrolling groups had a significantly lower mean hospital stay and operating time compared to the low-enrolling groups (P < 0.05). High-enrolling surgeons and institutions showed significantly shorter operating times, length of hospital stay, and complication rates. High-enrolling surgeons had significantly fewer device failures and cases of neurologic deterioration. Mean operating time and hospital stay were significantly lower in the randomized group (P < 0.05) compared to the nonrandomized group. Blood loss and approach-related complications were similar between the 2 groups. Device failure requiring removal was 4.2% in the nonrandomized group and 1.5% in the randomized group. Surgeons and institutions with a high volume of lumbar total disc replacement cases have a reduction in key perioperative and postoperative parameters that provide a clinical and/or economic benefit. Surgeons may expect longer hospital stays, higher blood loss, and a higher rate of certain complications in their early experience with total disc replacement procedures, but there was no effect on clinical outcomes.

A Prospective, Randomized, Multicenter Food and Drug Administration Investigational Device Exemption Study of Lumbar Total Disc Replacement With the CHARITÉ™ Artifiical Disc Versus Lumbar Fusion: Part II: Evaluation of Radiographic Outcomes and Correlation of Surgical Technique Accuracy With Clinical Outcomes

A Prospective, Randomized, Multicenter Food and Drug Administration Investigational Device Exemption Study of Lumbar Total Disc Replacement With the CHARITÉ™ Artifiical Disc Versus Lumbar Fusion: Part II: Evaluation of Radiographic Outcomes and Correlation of Surgical Technique Accuracy With Clinical Outcomes

Disc Prosthesis for Lumbar Degenerative Disease and Axial Instability—ProDisc

The Prodisc-L artificial disc replacement is a useful tool in the treatment of discogenic pain syndrome. The semi-constrained design allows for near anatomic motion while diminishing shear forces on the facets. The surgical technique is reproducible and allows for a minimally invasive safe approach. The sixteen year European experience has been excellent. Under the stringent criteria set forth by the United States Food and Drug Administration investigational device exemption trial, early reports of the Prodisc-L have shown at least equivalence to circumferential fusion with important short term benefits.

Complications of Lumbar Artificial Disc Replacement versus Fusion: Results from the Randomized, Multicenter Food and Drug Administration Investigational Device Exemption Study of the CHARITÉ Artificial Disc

Complications of Lumbar Artificial Disc Replacement versus Fusion: Results from the Randomized, Multicenter Food and Drug Administration Investigational Device Exemption Study of the CHARITÉ Artificial Disc

A Prospective, Randomized, Multicenter Food and Drug Administration Investigational Device Exemption Study of Lumbar Total Disc Replacement With the CHARITÉ ™ Artificial Disc Versus Lumbar Fusion

A prospective, randomized, multicenter, Food and Drug Administration-regulated, investigational device exemption clinical trial. To compare the safety and effectiveness of lumbar total disc replacement (TDR) with the CHARITE artificial disc (DePuy Spine, Raynham, MA) to anterior lumbar interbody fusion for the treatment of single-level degenerative disc disease from L4-S1 unresponsive to nonoperative treatment. In addition, to evaluate the radiographic outcomes of lumbar artificial disc replacement at either L4-L5 or L5-S1 with the CHARITE artificial disc as compared to anterior lumbar interbody fusion with cylindrical cages and iliac crest bone graft; and to determine if a correlation exists between clinical outcomes and surgical accuracy of TDR placement within the disc space. Prior investigators have reported excellent radiographic results with the CHARITE artificial disc for the treatment of lumbar degenerative disc disease. These encouraging results are the product of retrospective reviews without a control. Very few studies have reported on the segmental motion of an intervertebral level implanted with an artificial disc, and no studies have reported a correlation of radiographic and clinical outcomes. A prospective, randomized, multicenter, US Food and Drug Administration, investigational device exemption study with 24-month follow-up was performed at 14 centers throughout the United States. A total of 304 subjects were randomized in a 2:1 ratio, with 205 in the investigational group (TDR with the CHARITE artificial disc) and 99 in the control group (anterior lumbar interbody fusion with BAK cages and iliac crest bone graft). A total of 71 TDR training cases were performed (up to 5 at each site) before randomization beginning at each site. Plain radiographs were analyzed for each subject in both groups regarding range of motion (ROM) in flexion/extension, restoration of disc space height, and subsidence. Prosthesis placement in the coronal and midsagittal planes was analyzed for the 276 patients with TDR. Correlations were performed between prosthesis placement and clinical outcomes. Patients in the investigational group had a 13.6% mean increase, and those in the control group an 82.5% decrease in mean flexion/extension ROM at 24 months postoperatively compared to baseline. Patients in the investigational group had significantly better restoration of disc height than the control group (P < 0.05). There was significantly less subsidence in the investigational group compared to the control group (P < 0.05). The surgical technical accuracy of CHARITE artificial disc placement was divided into 3 groups: I, ideal (83%); II, suboptimal (11%); and III, poor (6%), and correlated with clinical outcomes. The flexion/extension ROM and prosthesis function improved with the surgical technical accuracy of radiographic placement (P = 0.003). Preoperative ROM in flexion/extension was restored and maintained in patients receiving a TDR. TDR with the CHARITE artificial disc resulted in significantly better restoration of disc space height, and significantly less subsidence than anterior interbody fusion with BAK cages. Clinical outcomes and flexion/extension ROM correlated with surgical technical accuracy of CHARITE artificial disc placement. In the majority of cases, placement of the CHARITE artificial disc was ideal.

Disc arthroplasty: lessons learned from total joint arthroplasty

Background context With the rapid emergence of new disc arthroplasty designs and ongoing clinical trials, there is great anticipation among clinicians. Inevitably there will be challenges associated with adoption of this new technology. Potential lessons learned from the extensive experience with extremity arthroplasty may predict some of the perils and pitfalls associated with motion-preserving devices in spinal applications. Purpose To review the extremity total joint literature for lessons that may be transferable to disc arthroplasty and anticipate predictable problems that will occur. Study design/setting A literature review and conjectural analysis of key lessons learned from the experience of extremity total joint arthroplasty and anterior lumbar interbody fusion devices with subsequent application of these lessons to disc arthroplasty in the lumbar spine. Methods Limited data are available on disc arthroplasty. Results Particular areas of controversy and uncertainty exist. The ongoing US Food and Drug Administration Investigational Device Exemption clinical trials may provide additional insight into these questions. Conclusions Complications will occur. These will be approach related, device related and patient-selection related. Studying the experience of extremity joint arthroplasty may accelerate the learning curve for lumbar disc arthroplasty.

Historical review of cervical arthroplasty

Early attempts at spinal arthroplasty in the 1950s yielded limited success. A revival of this procedure occurred in the 1980s and became a realistic treatment option in the 1990s. Both lumbar and cervical arthroplasties have been introduced in the US since 2000 for randomized, prospective studies in accordance with the Food and Drug Administration (FDA) investigational device exemption provisions. In June 2004 the first lumbar arthroplasty device was approved by the FDA for use in the US. It is likely that cervical arthroplasty will soon follow and may be available for widespread use as early as 2006. In this paper the authors review the historical development of cervical arthroplasty.

Pediatrics and social policy: Advocating for children's rights

We performed a prospective, single-arm clinical trial approved under a Food and Drug Administration Investigational Device Exemption to assess safety and efficacy of Perceval, a sutureless bovine pericardial aortic valve representing the initial US experience.From June 2013 to January 2015, 300 patients (mean age 76.7 ± 7.7 years, 54.3% men, 37.3% ≥80 years, median Society of Thoracic Surgeons Predicted Risk of Mortality 2.8%), underwent Perceval valve implantation at 18 centers across the United States. Twenty patients (6.7%) had a bicuspid aortic valve and 5 (1.7%) patients had previous aortic valve replacement. A minimally invasive approach was used in 80 (26.7%) and concomitant procedures were performed in 113 (37.8%) patients.Two hundred eighty-nine patients (96.3%) were successfully implanted. Operative mortality (≤30 days) was 1.3% (n = 4) (observed to expected ratio of 0.40). One-year results included all-cause mortality in 5.2% (n = 15), stroke in 1% (n = 3), and endocarditis in 1.7% (n = 5). New permanent periprocedural pacemaker rate was 10.7% (n = 30/281); 2.5% (n = 7/281) resulted from third-degree atrioventricular block. One-year valve-related reoperation was 2.1% (n = 6). At 1-year follow-up, 98% of patients were in New York Heart Association class I/II, left ventricular mass index decreased from 103.5 ± 30.1 g/m2 at discharge to 95.8 ± 27.1 g/m2 (P = .001), and 3 (1.3%) moderate paravalvular leaks were identified. Health-related quality of life score increased from 62.7 ± 21.8 before surgery to 85.5 ± 17.8 at 1 year (P < .001).These results confirm the safety and effectiveness of the Perceval sutureless aortic valve replacement in study patients with lower mortality than expected from a risk prediction model. Persistent hemodynamic benefit and improvement in quality of life at 1 year support the importance of this device in the management of aortic valve disease.

Clinical experience with an implantable, intracardiac, continuous flow circulatory support device: physiologic implications and their relationship to patient selection

Background We have been investigating continuous-flow circulatory support devices for 20 years. Unlike pulsatile assist devices, continuous-flow pumps have a simplified pumping mechanism and they do not require compliance chambers or valves. In the 1980s, clinical experience with the Hemopump proved a high-speed, intravascular, continuous-flow pump could safely augment the circulation. Subsequently, a decade of animal experiments with a larger, longer-term continuous-flow pump (the Jarvik 2000) confirmed the safety and efficacy of intraventricular placement, leading to its clinical application. Methods We analyzed the physiologic and anatomic effect of using the Jarvik 2000 pump for cardiac support in 23 patients in whom the device was applied as a bridge to transplant under the protocol approved by the Food and Drug Administration Investigational Device Exemption. The device was used as a bridge to transplantation in 20 patients and as destination therapy in 3 patients. Results In the bridge-to-transplant group, 14 patients underwent transplantation, 5 died during the circulatory support period and 1 is in an ongoing study. The support period lasted an average of 90 days. For the survivors, the follow-up period has averaged 16 months. Within the first 48 postoperative hours, the average cardiac index increased by 65% (from 1.77 ± 0.24 to 2.92 ± 0.60 L · min −1 · m −2, p = 0.00000002), the systemic vascular resistance decreased by 42% (from 1604 ± 427 to 930 ± 330 dynes/sec per cm 2, p = 0.00001), and the pulmonary capillary wedge pressure (PCWP) decreased by 41.8% (from 23 ± 5.1 to 13.4 ± 6.6 mm Hg, p = 0.00009). Similar results were seen for the patients undergoing destination therapy. Cardiac index increased 89.5% (from 1.9 ± 0.1 to 3.6 ± 0.6, p = 0.046) and PCWP decreased by 52.2% (from 23 ± 10 to 11 ± 2, p = 0.22). In that group, 1 patient died unexpectedly from an accident 382 days after device implantation. The 2 survivors remain in New York Heart Association (NYHA) functional class I at 700 to 952 days after implantation. Conclusions The Jarvik 2000 can offer effective long-term support for patients with chronic heart failure and NYHA class IV status. However, the new physiology produced by continuous offloading of the heart throughout the cardiac cycle has introduced unique clinical problems. The understanding of the problems generated by this biotechnological interface is essential for obtaining optimal clinical outcomes.

4:04 Retrograde ejaculation after anterior lumbar interbody fusion: transperitoneal versus retroperitoneal

Purpose of study: One of the most devastating complications of anterior lumbar interbody fusion (ALIF) in the young male patient is retrograde ejaculation. The purpose of this study is to compare the incidence of retrograde ejaculation in a group of patients undergoing ALIF through either a transperitoneal or retroperitoneal approach.Methods used: A total of 279 patients were entered into a randomized, prospective US Food and Drug Administration investigational device exemption (IDE) study evaluating recombinant human bone morphogenic protein (rhBMP)-2 in a tapered titanium cylindrical cage placed through an open anterior approach for treatment of symptomatic degenerative disc disease. Choice of retroperitoneal or transperitoneal approach was at the surgeon's discretion. All procedures were at the L4–L5 or L5–S1 level. The investigation group received rhBMP-2 and the control group autograft iliac crest bone in the cage. Of the 143 patients in the rhBMP-2 group, 78 were male. A retroperitoneal approach was performed on 61 and transperitoneal on 17. In the control group, 68 of 136 patients were male. Fifty-five had a retroperitoneal approach, and 13 had a transperitoneal approach. There is no reported influence of type of bone graft on retrograde ejaculation, so the groups were combined for evaluation. A total of 146 male patients were included in this study with 116 undergoing a retroperitoneal approach and 30 a transperitoneal approach. All male patients were advised preoperatively of the risk of retrograde ejaculation. Patients were questioned postoperatively about adverse events. If a patient reported retrograde ejaculation had occurred postoperatively, they were questioned at each subsequent visit to determine if it was a transient or permanent condition.of findings: Six of 146 male patients reported retrograde ejaculation. Two occurred in the retroperitoneal group (2 of 116) for a 1.7% rate. Four occurred in the transperitoneal group (4 of 30) for a 13.3% rate. This was statistically significant using the Fisher's exact test (p=.017). One patient who developed retrograde ejaculation had an L4–L5 fusion using a retroperitoneal approach and five had an L5–S1 fusion, four with a transperitoneal approach and one with a retroperitoneal approach. Two patients had resolution of their condition at the 1-year postoperative interval, one from the retroperitoneal group and one from the transperitoneal approach. One patient with transient symptoms had an L4–L5 fusion through the retroperitoneal approach, and one patient had an L5–S1 fusion through a transperitoneal approach. At the 2-year postoperative evaluation, four patients had persistent retrograde ejaculation. One was in the retroperitoneal group (1 of 116) for a rate of 0.86% and three in the transperitoneal group (3 of 30) for a rate of 10%. The difference in the rate of permanent retrograde ejaculation is statistically significant between the retroperitoneal and transperitoneal groups using the Fisher's exact test (p=.027)Relationship between findings and existing knowledge: The first reports of retrograde ejaculation after ALIF were made in the 1960s. Although a rare complication, concern arose in the 1990s when a higher rate was noted with laparoscopic procedures. The results of this study show a statistically significant higher rate of permanent retrograde ejaculation in men undergoing a transperitoneal compared with a retroperitoneal approach (10% vs. 0.86%).Overall significance of findings: Transperitoneal approaches to the lumbar spine at L4–L5 and L5–S1 have a 10 times higher chance of retrograde ejaculation compared with retroperitoneal approaches in male patients.Disclosures: No disclosures.Conflict of interest: Rick Sasso, MD, grant research support; Rick Sasso, MD, consultant; Kenneth Burkus, MD, grant research support; Kenneth Burkus, MD, consultant; Jean Charles LeHuec, MD, grant research support; Jean Charles LeHuec, MD, consultant.

Artisan phakic intraocular lens for myopia: Short-term results of a prospective, multicenter study

Purpose To evaluate the safety and efficiency of the Artisan iris-supported phakic intraocular lens (Ophtec BV, Groningen, Netherlands) for the correction of high myopia. Study design Nonrandomized, prospective, multicenter trial conducted under a United States Food and Drug Administration (FDA) Investigational Device Exemption. Participants One hundred fifty-five eyes of 155 patients with myopia from −5.5 to −22.5 diopters (D) underwent implantation of an Artisan lens, as part of a phase I, II, or III FDA trial. Methods Eyes were examined at 1 day (154 eyes), 2 weeks (142 eyes), 2 months (130 eyes), and 6 months (84 eyes). Intraocular pressure and presence of flare and cell on slit-lamp biomicroscopy were recorded at each visit. Main outcome measures Achieved correction, stability of spherical equivalent refraction, change in astigmatism, postoperative uncorrected vision, change in best spectacle-corrected acuity, and change in endothelial cell count. Results Mean spherical equivalent manifest refraction stabilized on postoperative day 1. Mean difference between attempted and achieved correction at 2 months was −0.32 ± 0.95 D (mean ± standard deviation; range, −4.42 to +2.2 D). At 6 months, 85% of eyes saw 20/40 or better uncorrected, and 90% of eyes were within 1 D of the attempted correction. Refractive astigmatism increased in 4.8% of eyes and decreased in 17% of eyes at 6 months. At 2 months, six eyes (4.8%) lost two or more lines of best spectacle-corrected visual acuity; by 6 months, no eyes lost two or more lines of best-corrected visual acuity. Endothelial cell count was unchanged at 6 months compared with the preoperative count. Nonprogressive lens opacities developed in four eyes as a result of surgical trauma. Chronic inflammation was not detected in any eye by slit-lamp biomicroscopy, nor did any eye develop angle closure or glaucoma. Conclusions Short-term results suggest that the Artisan lens is an accurate and safe method for the correction of high myopia. Surgical skill is important in avoiding lens opacities. Longer-term data are needed to assess the impact of the lens on the endothelium, the crystalline lens, and the iris.

Increasing incidence of midterm and long-term complications after endovascular graft repair of abdominal aortic aneurysms: a note of caution based on a 9-year experience.

To analyze the late complications after endovascular graft repair of elective abdominal aortic aneurysms (AAAs) at the authors' institution since November 1992. Recently, the use of endovascular grafts for the treatment of AAAs has increased dramatically. However, there is little midterm or long-term proof of their efficacy. During the past 9 years, 239 endovascular graft repairs were performed for nonruptured AAAs, many (86%) in high-risk patients or in those with complex anatomy. The grafts used were Montefiore (n = 97), Ancure/EVT (n = 14), Vanguard (n = 16), Talent (n = 47), Excluder (n = 20), AneuRx (n = 29), and Zenith (n = 16). All but the AneuRx and Ancure repairs were performed as part of a U.S. phase 1 or phase 2 clinical trial under a Food and Drug Administration investigational device exemption. Procedural outcomes and follow-up results were prospectively recorded. The major complication and death rates within 30 days of endovascular graft repair were 17.6% and 8.5%, respectively. The technical success rate with complete AAA exclusion was 88.7%. During follow-up to 75 months (mean +/- standard deviation, 15.7 +/- 6.3 months), 53 patients (22%) died of unrelated causes. Two AAAs treated with endovascular grafts ruptured and were surgically repaired, with one death. Other late complications included type 1 endoleak (n = 7), aortoduodenal fistula (n = 2), graft thrombosis/stenosis (n = 7), limb separation or fabric tear with a subsequent type 3 endoleak (n = 1), and a persistent type 2 endoleak (n = 13). Secondary intervention or surgery was required in 23 patients (10%). These included deployment of a second graft (n = 4), open AAA repair (n = 5), coil embolization (n = 6), extraanatomic bypass (n = 4), and stent placement (n = 3). With longer follow-up, complications occurred with increasing frequency. Although most could be managed with some form of endovascular reintervention, some complications resulted in a high death rate. Although endovascular graft repair is less invasive and sometimes effective in the long term, it is often not a definitive procedure. These findings mandate long-term surveillance and prospective studies to prove the effectiveness of endovascular graft repair.

Ventricular assist devices as a bridge to cardiac transplantation. A prelude to destination therapy.

Ventricular assist devices (VADs) have been used for temporary circulatory support pending transplantation or recovery of the native heart. Outcome in 38 patients treated at the authors' institution with VADs pending transplantation was analyzed to provide information relevant to the future use of VADs as permanent implants. Thoratec (Thoratec Laboratories, Pleasanton, CA) or HeartMate (Thermo Cardiosystems, Woburn, MA) VADs were used in all cases. Patients were considered for VAD placement if they were candidates for cardiac transplantation and fulfilled the criteria for the Food and Drug Administration investigational Device Exemption trials. The following adverse events were included in the analysis; death during VAD support, device malfunction, bleeding, neurologic events, support-related events that preclude transplantation, and device-related infections. Patient survival and complication rates were quantified using the Kaplan-Meier method, competing risk analysis, and hazard functions. Nineteen patients had transplantation. Three patients had VAD removal after cardiac recovery and 16 died without transplantation. The duration of VAD support ranged from 0 to 279 days. The hazard function for death during VAD support had an early phase that lasted for 2 weeks after VAD placement, and early death was related to the preimplant condition of the patient. Device-related infections were noted in 11 patients. Seven of these patients had transplantation after clearing the infection, whereas four died without transplantation. Neurologic events occurred in seven patients. There were no device malfunctions that led to patient death. The absence of fatal device malfunctions suggests that longer term support with current VAD designs is feasible. Appropriate patient selection, infection control, and avoidance of thromboembolic neurologic complications will be crucial to the success of permanent VAD use.