Platelet-rich plasma as an effective treatment for proximal hamstring injuries

Proximal hamstring injuries can be disabling, and several traditional conservative treatments, including physiotherapy and nonsteroidal anti-inflammatory drugs, have been inconsistent. Corticosteroid injections have demonstrated success but can adversely affect local tissues. Platelet-rich plasma (PRP) has emerged as a safe, effective treatment for several orthopedic pathologies. The authors propose a PRP injection at the muscle origin as a novel treatment for proximal hamstring injuries. A retrospective review yielded 15 patients with 17 proximal hamstring injuries. Twelve injuries failed traditional conservative treatment and were ultimately treated with a PRP injection at the hamstrings muscle origin. Five patients were treated with traditional conservative treatment alone. Analysis included pre- and posttreatment visual analog scale scores, Nirschl Phase Rating Scale scores, and return to sport. No significant difference existed between the groups' pretreatment visual analog scale scores (P=.28) and Nirschl Phase Rating Scale scores (P=.15) and their posttreatment visual analog scale scores (P=.38) and Nirschl Phase Rating Scale scores (P=.22). The PRP group demonstrated a reduction in visual analog scale scores (P<.01) and Nirschl Phase Rating Scale scores (P<.01), but the traditional conservative treatment group did not demonstrate the same reduction (P=.06 and .06, respectively). All athletes returned to their desired activity level with no major complications.

All-arthroscopic iliotibial band autograft harvesting and labral reconstruction technique

The labrum is essential for stability, movement, and prevention of arthritis in the hip. In cases of labral damage where repair of a labral tear is not possible, reconstruction can be a useful alternative. Several different autografts have been used, including the iliotibial band (ITB), the ligamentum teres capitis, and the gracilis tendon. Authors have reported both open and arthroscopic techniques for reconstruction with good preliminary results. However, an all-arthroscopic labral reconstruction technique including the graft harvest and reconstruction portions of a labral reconstruction procedure using an ITB autograft has not been previously described. We describe a technique for an all-arthroscopic labral reconstruction performed using a novel method for arthroscopic harvest of the ITB. The decreased invasiveness of our described technique for labral reconstruction may potentially minimize scarring, bodily disfigurement, infection, and postoperative pain associated with the graft harvesting incision.

Efficacy of preoperative home use of 2% chlorhexidine gluconate cloth before shoulder surgery

HYPOTHESIS

Deep infection after shoulder surgery is a rare but devastating problem. This study tested the hypothesis that the home application of a 2% chlorhexidine gluconate cloth before shoulder surgery would be more efficacious than a standard shower of soap and water at decreasing the preoperative cutaneous levels of pathogenic bacteria on the shoulder.

MATERIALS AND METHODS

This randomized, prospective study evaluated 100 consecutive patients undergoing shoulder surgery. Patients were randomly assigned to use 2% chlorhexidine gluconate-impregnated cloths (treatment group) or to shower with soap and water before surgery (control group). Cutaneous cultures were taken from the patients'shoulders in the preoperative holding area. Patients were monitored for 2 months postoperatively for clinical signs of infection.

RESULTS

In the treatment group vs the control group, the overall positive culture rate was 66% vs 94% (P = .0008), and the positive culture rate for coagulase-negative Staphylococcus was 30% vs 70% (P = .0001). The positive culture rate for Propionibacterium acnes was 46% in the treatment group vs 58% in the control group (P = .32). No infections occurred in any patients at a minimum of 2-months after surgery.

DISCUSSION

The use of the 2% chlorhexidine cloth was effective at decreasing overall bacterial culture rates before shoulder surgery and was particularly effective at decreasing the quantity of coagulase-negative Staphylococcus, a known causative agent of postoperative shoulder infections.

CONCLUSION

Use of chlorhexidine impregnated cloths prior to shoulder surgery may be a useful adjunct to presently used infection prevention strategies.

The Professional Athlete Spine Initiative: outcomes after lumbar disc herniation in 342 elite professional athletes

BACKGROUND CONTEXT

Although clinical outcomes after lumbar disc herniations (LDHs) in the general population have been well studied, those in elite professional athletes have not. Because these athletes have different measures of success, studies on long-term outcomes in this patient population are necessary.

PURPOSE

This study seeks to define the outcomes after an LDH in a large cohort of professional athletes of American football, baseball, hockey, and basketball.

STUDY DESIGN/SETTING

Retrospective cohort study.

PATIENT SAMPLE

A total of 342 professional athletes from four major North American sports from 1972 to 2008 diagnosed with an LDH were identified via a previously published protocol. Two hundred twenty-six players underwent lumbar discectomy, and 116 athletes were treated nonoperatively. Only those players who had at least 2 years of follow-up were included.

OUTCOME MEASURES

Functional outcome measures as defined by successful return-to-play (RTP), career games, and years played for each player cohort were recorded both before and after treatment. Conversion factors based on games/regular season and expected career length (based on individual sport) were used to standardize the outcomes across each sport.

METHODS

Using Statistical Analysis Software v. 9.1, outcome measures were compared in each cohort both before and after treatment using linear and mixed regression analyses and Cox proportional hazards models. A Kaplan-Meier survivorship curve was calculated for career length after injury. Statistical significance was defined as p<.05.

RESULTS

After the diagnosis of an LDH, professional athletes successfully returned to sport 82% of the time, with an average career length of 3.4 years. Of the 226 patients who underwent surgical treatment, 184 successfully returned to play (81%), on average, for 3.3 years after surgery. Survivorship analysis demonstrated that 62.3% of players were expected to remain active 2 years after diagnosis. There were no statistically significant differences in outcome in the surgical and nonoperative cohorts. Age at diagnosis was a negative predictor of career length after injury, whereas games played before injury had a positive effect on outcome after injury. Major League Baseball (MLB) players demonstrated a significantly higher RTP rate than those of other sports, and conversely, National Football League (NFL) athletes had a lower RTP rate than players of other sports (p<.05). However, the greatest positive treatment effect from surgery for LDH was seen in NFL players, whereas for MLB athletes, a lumbar discectomy led to a shorter career compared with the nonoperative cohort (p<.05).

CONCLUSIONS

Professional athletes diagnosed with an LDH successfully returned to play at a high rate with productive careers after injury. Whereas older athletes have a shorter career length after diagnosis of LDH, experienced players (high number of games played) demonstrate more games played after treatment than inexperienced athletes. Notably, surgical treatment in baseball players led to significantly shorter careers, whereas for NFL athletes, posttreatment careers were longer than those of the corresponding nonoperative cohort. The explanation for this is likely multifactorial, including the age at diagnosis, respective contractual obligations, and different physical demands imposed by each individual professional sport.

Cyclic testing of 3 all-inside meniscal repair devices: a biomechanical analysis

BACKGROUND

Despite the growing popularity of all-inside meniscal repair devices, concerns remain about their fixation strength. It is also unclear which of these devices have the most ideal biomechanical properties.

PURPOSE

To compare the biomechanical properties of 3 all-inside meniscal repair devices: the Meniscal Cinch, Ultra FAST-FIX, and MaxFire.

STUDY DESIGN

Controlled laboratory study.

METHODS

Twenty-seven human cadaveric menisci (3 groups of 9) were repaired using 3 different meniscal repair devices. The repaired menisci were then subjected to cyclic loading and load-to-failure testing. Gap formation and ultimate load to failure were measured.

RESULTS

Six of the devices failed during cyclic testing, 4 in the MaxFire group (44%), 1 in the Ultra FAST-FIX group (11%), and 1 in the Meniscal Cinch group (11%). After 1 cycle, there was a trend toward larger gap formation in the MaxFire group (3.65 mm) compared with the Meniscal Cinch group (2.12 mm, P = .05). After 100 cycles, group differences were found in gap formation (P = .03), with the MaxFire group exhibiting greater displacement (6.70 mm) than the Ultra FAST-FIX group (3.59 mm). After 500 cycles, group differences in gap formation (Meniscal Cinch, 5.94; Ultra FAST-FIX, 4.74 mm; Max Fire, 7.19 mm) did not reach statistical significance (P = .20). A trend was found toward higher ultimate load to failure in the Ultra FAST-FIX (86.1 N) and Meniscal Cinch (85.3 N) groups compared with the MaxFire group (64.5 N, P = .06). Stiffness was also higher in the Ultra FAST-FIX (25.2 N/mm) and Meniscal Cinch (25.5 N/mm) groups than the MaxFire group (16.3 N/mm, P = .02).

CONCLUSION

The Meniscal Cinch and Ultra FAST-FIX devices have more desirable biomechanical properties than the MaxFire as demonstrated by higher stiffness and a lower failure rate during cyclic testing.

CLINICAL RELEVANCE

The Meniscal Cinch and Ultra FAST-FIX devices may be more desirable implants for use during all-inside meniscal repair as they have superior biomechanical properties when compared with the MaxFire device.

Biomechanical evaluation of a rotator cuff defect model augmented with a bioresorbable scaffold in goats

A bioresorbable patch used for augmentation of rotator cuff repair was evaluated to determine if it would increase strength of cuff repairs associated with tendon defects and also show histologic incorporation over time. Forty goats underwent rotator cuff repairs of the infraspinatus tendon bilaterally. Tendons were detached and a defect was created prior to repair. One side was repaired and augmented with a 4 cm2 polylactic acid patch in each animal. On the other side, the same size defect was repaired in the same manner but without the patch to serve as a control. Animals were sacrificed at 3, 6, 12, and 24 weeks. Ultimate load to failure and histology were reported. No significant difference in load to failure was found between groups. A cellular fibrous tissue occupied the patch at 6 weeks, which over time matured into a dense, homogeneous fibrous tissue with alignment of collagen between the scaffold bundles.

Measurement variance in limb length discrepancy: clinical and radiographic assessment of interobserver and intraobserver variability

The purpose of this study was to assess interobserver and intraobserver variability in the assessment of clinical and radiographic measurement of lower limb length discrepancy. Clinical measurements included direct measurement with a tape measure from anterior superior iliac spine (ASIS) to lateral malleolus and ASIS to medial malleolus as well as block measurement. Slit scanogram radiographic measurement was also evaluated. All three clinical measurements had excellent reliability, but the relatively large mean differences and the large 95% confidence intervals for clinical measurements limit the usefulness of these techniques. Slit scanogram measurement was the most reliable measurement technique. The intraobserver variance of direct slit scanogram measurement included intraclass correlation coefficient of 0.99, mean difference of 0.1 cm, and 95% confidence interval of 0.4 cm. Results were not influenced by patient age or body mass index. Slit scanogram measurement is the preferred method for assessment of limb length discrepancy. The direct slit scanogram measurement described in the text follows the mechanical axis line of the leg in the "at ease" standing position described by Paley. Direct measurement using a measuring tape on a full-length slit scanogram is more reliable than indirect measurement using horizontal lines drawn to a radiolucent ruler that is positioned by a technician, since direct measurement avoids errors due to nonparallel positioning of the limb relative to the ruler, and direct measurement also avoids errors due to non-horizontal lines drawn from standard bony landmarks to the ruler. The ideal radiographic measurement technique would have high reliability and accuracy and would minimize or eliminate radiation.

Thromboembolic disease prophylaxis in patients with hip fracture: a multimodal approach

OBJECTIVES

To assess if pneumatic compression in conjunction with chemoprophylaxis is an effective way to reduce the incidence of deep vein thrombosis in orthopedic trauma patients sustaining fragility hip fractures.

DESIGN

Two hundred patients admitted to the authors' institution between May 1998 and June 2002 for fractures of the hip were prospectively studied. All patients were treated operatively and received the VenaFlow calf compression device on both lower extremities immediately following surgery. Chemical prophylaxis of either aspirin (n = 67) or warfarin (n = 133) was administered in addition to mechanical compression. A noninvasive serial color flow duplex scan was performed 1 to 11 days postoperatively (mean 4.5 days) to determine the presence or absence of deep vein thrombosis. All patients were followed clinically 3 months postoperatively for a clinical evaluation of symptomatic deep vein thrombosis or pulmonary embolism.

RESULTS

Overall, the incidence of deep vein thrombosis was 3.5% (7 of 200) and included only 1 proximal thrombosis (1 out of 200, or 0.5%) and no pulmonary embolism. Five of the 7 patients positive for deep vein thrombosis were in the mechanical compression and warfarin prophylaxis group and 2 were in the aspirin arm of the study. For patients with deep vein thrombosis, the average number of risk factors was 3.71, whereas patients without clots averaged 1.75 clinical risk factors (P < or = 0.05). Three patients in the warfarin group developed bleeding complications (1 with a gastrointestinal bleed and 2 with minor bleeding not at the operative site). No evidence of a symptomatic deep vein thrombosis or pulmonary embolism was reported within a 3-month period following hospitalization.

CONCLUSIONS

Our findings suggest mechanical compression with the VenaFlow calf compression device in conjunction with chemoprophylaxis is an effective means of reducing thromboembolic disease in this high-risk population.

Deep lamellar endothelial keratoplasty (DLEK): pursuing the ideal goals of endothelial replacement

Endothelial dysfunction is a leading cause of corneal vision loss and treatment requires surgical replacement with donor endothelium. Standard penetrating keratoplasty (PK) suffers from the inherent problems of surface corneal incisions and sutures and poor wound healing of vertical stromal wounds. This often results in high irregular astigmatism, unpredictable corneal power, and the risk of long-term visual loss from suture-induced vascularization, ulceration, rejection, and late wound rupture. This paper delineates five ideal goals of endothelial replacement, which include: (1) a smooth surface topography without significant change in astigmatism from preoperative to postoperative; (2) a highly predictable and stable corneal power; (3) a healthy donor endothelium that resolves all oedema; (4) a tectonically stable globe, safe from injury and infection; and (5) an optically pure cornea. Deep lamellar endothelial keratoplasty (DLEK) is a surgical method of endothelial replacement that is performed through a limbal scleral incision that leaves the surface of the recipient cornea untouched. The early results of this innovative surgery are discussed and compared to the results of PK in terms of fulfillment of the five ideal goals of endothelial replacement. With further refinement of interface creation, DLEK surgery may be the ideal method for endothelial replacement.

Dry eye in the elderly

Dry eye in the elderly population is a condition with a multitude of contributing factors and a wide spectrum of severity. The complex tear film is made up of layers of oil, aqueous and mucin, produced by the meibomian glands, main and accessory lacrimal glands, and by the goblet cells, respectively. Alteration in the normal function of any of these structures by disease, trauma or the environment can cause dysfunction of the tear film and result in the symptoms of dry eye (such as burning, grittiness and blurred vision). Normal lid anatomy and closure is critical to prevent evaporation of the normal tear film. The mainstay of current therapy is augmentation of the tear film with artificial tears and ointment. More severe cases of dry eye may require occlusion of the tear drainage system with plugs or electrocautery scarring. Good lid hygiene is also important for tear film health. A new paradigm of dry eye as a subclinical inflammatory disease has recently been suggested, and preliminary results from treatment with topical cyclosporin formulations are encouraging. The next few years promise exciting advances and relief for patients suffering from this chronic condition.

A comprehensive investigation of barriers to adult immunization: a methods paper

OBJECTIVE

Immunization rates for influenza and pneumococcal vaccines among the elderly (especially minority elderly) are below desired levels. We sought to answer 4 questions: (1) What factors explain most missed immunizations? (2) How are patient beliefs and practices regarding adult immunization affected by racial or cultural factors? (3) How are immunizations and patient beliefs affected by physician, organizational, and operational factors? and (4) Based on the relationships identified, can typologies be created that foster the tailoring of interventions to improve immunization rates?

STUDY DESIGN

A multidisciplinary team chose the PRECEDE-PROCEED framework, the Awareness-to-Adherence model of clinician response to guidelines, and the Triandis model of consumer decision making as the best models to assess barriers to and facilitators of immunization. Our data collection methods included focus groups, face-to-face and telephone interviews, self-administered surveys, site visits, participant observation, and medical record review.

POPULATION

To encounter a broad spectrum of patients, facilities, systems, and interventions, we sampled from 4 strata: inner-city neighborhood health centers, clinics in Veterans Administration facilities, rural practices in a network, and urban/suburban practices in a network. In stage 1, a stratified random cluster sample of 60 primary care clinicians was selected, 15 in each of the strata. In stage 2, a random sample of 15 patients was selected from each clinician's list of patients, aiming for 900 total interviews.

CONCLUSIONS

This multicomponent approach is well suited to identifying barriers to and facilitators of adult immunizations among a variety of populations, including the disadvantaged.

Deep lamellar endothelial keratoplasty in the first United States patients: early clinical results

PURPOSE

To report the early clinical results of the first U.S. patients to undergo deep lamellar endothelial keratoplasty (DLEK) surgery for the treatment of endothelial dysfunction.

METHODS

Two patients with pseudophakia with Fuchs' endothelial dystrophy, under an Institutional Review Board-approved protocol, underwent replacement of the endothelium through a limbal, scleral pocket incision (DLEK). Their vision, pachymetry, and corneal map topography were measured in the early postoperative period and were compared with preoperative measurements.

RESULTS

Both patients had improvement in all parameters within 1 month after surgery, and corneal topography showed no significant change from before the surgery. The first patient's vision at 6 months was 20/40 (+2) with a 0.75-diopter (D) decrease in astigmatism and a normal pachymetry of 573 microm. The second patient's vision at 6 months was 20/40 (-2) with a 0.25-D increase in astigmatism and a pachymetry of 618 microm. Graft endothelial cell counts at 6 months were 1,692 and 2,631 cells/mm2, respectively.

CONCLUSION

The DLEK procedure, with its absence of corneal surface incisions and sutures, preserves the preoperative topography and demonstrates good donor endothelial cell count and function early in the postoperative period. If interface clarity can be maintained, the potential advantages over penetrating keratoplasty in the treatment of endothelial dysfunction are considerable.

Endothelial replacement without surface corneal incisions or sutures: topography of the deep lamellar endothelial keratoplasty procedure

PURPOSE

To evaluate the immediate postoperative corneal topography after the deep lamellar endothelial keratoplasty procedure.

METHODS

Eight eye bank eyes underwent deep lamellar endothelial keratoplasty through a 9.0-mm limbal incision replacing the central 7.0 mm of posterior stroma and endothelium through the lamellar pocket wound. Orbscan topography was performed before and after surgery, and simulated keratometry readings and central corneal diopter power were recorded. The change in astigmatism and corneal power from preoperative to postoperative readings was then determined.

RESULTS

The net change in corneal astigmatism averaged 0.4+/-0.5 diopters (range, -0.1 to 1.1 diopters). The net change in corneal power averaged -0.2+/-0.4 diopters of flattening (range, -0.9 to +0.2 diopters). Neither the astigmatism nor the corneal power levels after this surgery were significantly different from the preoperative topography (p = 0.22 and 0.27, respectively).

CONCLUSIONS

The deep lamellar endothelial keratoplasty procedure, with its absence of corneal surface incisions or sutures, has no significant effect on immediate postoperative corneal topography. The potential advantages of this procedure over penetrating keratoplasty in the treatment of endothelial dysfunction are considerable.

The evolution of lamellar grafting techniques over twenty-five years

The history of lamellar keratoplasty (LK) surgery spans over 100 years, and the advantages of lamellar surgery have long been known. The surgery is usually used for tectonic purposes; however, new techniques and technology over the past 25 years have expanded the applications of LK in optical rehabilitation. Instrumentation such as viscoelastics, diamond knives, ultrasonic pachymetry, artificial anterior chambers, advanced microkeratomes, and the excimer laser have enhanced our ability to work more safely in the tedious microsurgical environment of the lamellar procedure. Advances in surgical techniques such as deep lamellar anterior keratoplasty and deep lamellar endothelial keratoplasty have expanded the application of lamellar surgery to endothelial replacement and have achieved visual results approaching those of penetrating keratoplasty while reducing the rate of rejection and improving the long-term graft stability. As research continues, LK promises to be an increasingly important option for the corneal surgeon.

The role of technical assistance in the replication of effective HIV interventions

This article examines the role of technical assistance (TA) in supporting the replication of proven HIV interventions. A case study of the replication of the VOICES/VOCES intervention elucidates the level and types of TA provided to support new users through the adoption process. TA included help in garnering administrative support, identifying target audiences, recruiting groups for sessions, maintaining fidelity to the intervention's core elements, tailoring the intervention to meet clients' needs, strengthening staff members' facilitation skills, troubleshooting challenges, and devising strategies to sustain the intervention. Two to four hours per month of TA were provided to each agency adopting the intervention, at an estimated monthly cost of $206 to $412. Findings illustrate how TA supports replication by establishing a conversation between the researcher TA providers experienced with the intervention and new users. This communication helps preserve key program elements and contributes to ongoing refinement of the intervention.

Orientation and training: preparing agency administrators and staff to replicate an HIV prevention intervention

Effective orientation and training are fundamental to the successful implementation of any intervention because they communicate the critical first impressions of the intervention and the skills needed to conduct it. When research-based HIV prevention interventions are translated into practice, issues arise that require adaptation and expansion of the basic functions of orientation and training. This article identifies some of these issues by drawing on the experience of researchers in the Replicating Effective Programs (REP) project. The purpose, structure, and instructional approach of the orientation and training for administrators, staff, and volunteers are described in depth for one project, with comparisons and additional examples from others. Based on these descriptions, critical issues for orientation and training for replication are presented. These include extending orientation and training to a broad audience within the adopting agency, allocating sufficient time to ensure understanding of the intervention, and planning for staff turnover.

From science to application: the development of an intervention package

Many community-based organizations and health departments want to implement HIV prevention interventions with scientifically demonstrated effectiveness. The Replicating Effective Programs (REP) project supported researchers in developing intervention packages designed to help prevention partners replicate effective programs in their settings. Intervention packages convey the intervention's foundation, components, and methods and are one part of a larger system needed to transfer research-based HIV prevention technology to service providers. Implementation packages were developed using a multistage process. The original researchers drafted the materials, advisory groups reviewed the packages, and adopting agencies used the materials in trial runs. The advisory groups and adopting agencies recommended extensive use of examples, thorough explanations about the rationale for each intervention component, explicit representation of people of color in the materials, clear statements about the intended audience(s), and an easy-to-use and visually appealing format. Packages were revised based on these recommendations and the outcomes of the trial runs.

Transfer of research-based HIV prevention interventions to community service providers: fidelity and adaptation

HIV prevention research interventions usually follow protocols with specific procedures. If a community-delivered intervention uses the same procedures with the same populations as those in the original research, the behavior change effects should be similar. However, community-based providers may not replicate an intervention exactly as it was conducted in the effectiveness study. Adaptation may be needed to better meet the needs of the clients, community, or organization. We propose that interventions can be defined in terms of core elements likely to be responsible for effectiveness. These core elements cannot be changed without fundamentally changing the intervention, whereas other characteristics may be modified without altering effectiveness. HIV prevention researchers and service providers can collaborate to develop interventions that not only are effective but can also be successfully implemented by service organizations. If researchers actively involve service providers and community members in intervention planning, technology transfer goals can be better achieved.

Oxidative cell membrane alteration. Evidence for surfactant-mediated sealing

Exposure to very intense ionizing irradiation produces acute tissue sequelae including inflammation, pain, and swelling that often results in tissue fibrosis and/or necrosis. Acute tissue necrosis occurs in hours when sufficiently rapid damage to membrane lipids and proteins leads to altered membrane structure, disrupting the vital electrochemical diffusion barrier necessary for cell survival. This damage mechanism is thought to underlie the interphase death of lethally irradiated postmitotic cells such as neurons, but it has also been implicated in the rapid cell death of lymphocytes and acute vascular changes due to capillary epithelium dysfunction. It is not known whether sealing of radiation-permeabilized cell membranes will prolong survival of lethally irradiated cells or perhaps lead to repair of damaged nucleic acids. The purpose of this study is to begin to address the first question.

New screening methods for donor eye-bank eyes

PURPOSE

Current methods of screening donor eyes for corneal transplantation are not always effective in excluding corneas with abnormal topography. We used the Orbscan to determine whether corneal-thickness maps could be used as a technique for donor tissue screening.

METHODS

Forty eye-bank eyes were measured with the Orbscan, and a corneal-thickness map was generated. Average central pachymetry measurements from each map were compared with the thinnest midperipheral thickness reading. Two eyes from a donor who had photorefractive keratectomy (PRK) and two eyes from a donor with keratoconus were then compared with the normal donor eye results.

RESULTS

The average difference between the thinnest midperipheral pachymetry and the central pachymetry in the control group was 0.040 +/- 0.026 mm. The eyes from the donor with PRK showed larger disparities between the central and midperipheral thicknesses because of the thinned central cornea, with differences of 0.154 mm in the right eye and 0.106 mm in the left eye. The eyes from the donor with keratoconus had midperipheral corneas that were thinner than the center, indicating eccentric, ectatic cones. The differences in thickness between the center and midperiphery in the eyes from the donor with PRK and the donor with keratoconus differed from the control group by >2 SD.

CONCLUSIONS

Diseases or surgery that affect the relationship between the central and midperipheral corneal thickness may be screened through Orbscan pachymetry mapping with comparison with a normal range.

Evaluation of prior photorefractive keratectomy in donor tissue

PURPOSE

To describe a case in which an eye donor had prior bilateral photorefractive keratectomies and to elucidate possible methods of evaluation and screening of donor tissue.

METHODS

Case report. A 62-year-old eye donor was reported to have received radial keratotomy before his death. Further investigation by the eye bank showed a history of photorefractive keratectomy (PRK), not radial keratotomy. The corneas were therefore not used for transplantation, and the eyes were evaluated by slit-lamp examination, photography, corneal topography, and histology.

RESULTS

Slit-lamp and photographic examination did not indicate the presence of PRK ablations. Corneal topography mapping with the TMS-1 was relatively ambiguous for identifying PRK flattening, while multiple data formatting of the cornea with the Orbscan resulted in the strongest suggestion of prior PRK. Histologic analysis showed central corneal thinning and loss of Bowman's membrane consistent with PRK.

CONCLUSIONS

In the absence of a positive donor history for PRK, current methods of screening donor tissue for prior PRK often are insufficient to exclude these corneas from use in transplantation. More refined placido imagery corneal topography or newer technologies such as the Orbscan may allow more sensitive and specific methods of donor tissue screening.

The Women and Infants Demonstration Project: an integrated approach to AIDS prevention and research

The Women and Infants Demonstration Project is a multisite, behavioral intervention research effort funded by the Centers for Disease Control. The project is evaluating a theory-based, integrated intervention model to increase the use of condoms for prevention of both sexually transmitted diseases (STDs) and unintended pregnancy among women and their partners at risk of infection with HIV. The importance of utilizing carefully targeted, credible and persistent risk reduction interventions to effect lasting behavior change has become evident over the last ten years of the AIDS epidemic. The theory-based intervention components being evaluated in this intervention study involve one-on-one stage-tailored outreach; the development and distribution of community-tailored HIV prevention materials, called role-model stories; and the development of organizational and peer networking, all within a community mobilization framework. This article describes each of the intervention components being evaluated during this 5-year study. Such an intervention effort represents an important contribution in the design of community-level AIDS prevention intervention efforts which support individual-level behavioral changes by women at risk for HIV and other sexually transmitted infections.

Variability in Corneal Thickness Before, During, and After Radial Keratotomy

BACKGROUND

Precision in radial keratotomy requires accurate pachymetry for safety and efficacy. We evaluated the location, timing, and extent of changes in corneal thickness between those determined by preoperative measurement in the clinic and those determined by pre-incision and post-incision measurement in the operating room.

METHODS

Sixty eyes of 37 patients had ultrasonic pachymetry measurements of the central and paracentral cornea taken in the clinic 20 minutes before each patient underwent radial keratotomy. The pachymetry was repeated intraoperatively immediately before and, in a subset of 17 eyes, immediately after incisions were made, and the readings were compared.

RESULTS

The thinnest of the four paracentral readings measured just prior to placing the radial keratotomy incisions was located temporally in 92% of the eyes and inferiorly in 8%. Corneas progressively thinned from clinic to surgery by an average of 7 +/- 12 microns centrally and 10 +/- 18 microns temporally. Additional thinning of 13 +/- 14 microns centrally and 22 +/- 23 microns temporally occurred during surgery.

CONCLUSION

The thinnest paracentral corneal region measured in an eye was not always located in the same quadrant preoperatively and intraoperatively. During the time of incision placement, significant corneal thinning had occurred at each incision site. Individual variations in corneal thickness between that measured preoperatively and that measured during surgery cautions against the use of clinic readings for diamond knife settings during radial keratotomy.