Small-angle strabismus detection by telemedicine in an experimental model

PURPOSE

To evaluate the ability of observers to accurately detect strabismus using an alternate cover testing approach via telemedicine and to assess the effect of various factors related to video conditions on the accuracy rate.

METHODS

Videos were made by the authors in which different angles of strabismus, up to 12Δ, were induced by prism and recorded using alternate cover testing. The videos were made under a variety of conditions that incorporated various head postures, lighting, fixation target position and motion, and viewing angle. The videos were shown to observers of varying levels of expertise. The accuracy of detecting the deviation was assessed and analyzed for statistical significance.

RESULTS

The overall rate of detection was significantly affected by the angle of deviation, with 12Δ being correctly detected with 94% accuracy, 8Δ with 72% accuracy, and 4Δ with <50% accuracy. Esotropia and hypertropia were more accurately detected than exotropia for all angles tested. The level of training of the observer did not correlate with detection accuracy. However, accuracy was negatively affected by backlighting and movement of the fixation target during cover testing.

CONCLUSIONS

Our data demonstrate that detection of even relatively small angles of strabismus can be accomplished with a high level of accuracy using telemedicine and an alternate cover testing strategy. For optimal results, it is important to consider conditions related to the fixation target and lighting.

Non-surgical management and analgesia strategies for older adults with multiple rib fractures: A systematic review, meta-analysis, and joint practice management guideline from the Eastern Association for the Surgery of Trauma and the Chest Wall Injury Society

BACKGROUND

Chest wall injury in older adults is a significant cause of morbidity and mortality. Optimal nonsurgical management strategies for these patients have not been fully defined regarding level of care, incentive spirometry (IS), noninvasive positive pressure ventilation (NIPPV), and the use of ketamine, epidural, and other locoregional approaches to analgesia.

METHODS

Relevant questions regarding older patients with significant chest wall injury with patient population(s), intervention(s), comparison(s), and appropriate selected outcomes were chosen. These focused on intensive care unit (ICU) admission, IS, NIPPV, and analgesia including ketamine, epidural analgesia, and locoregional nerve blocks. A systematic literature search and review were conducted, our data were analyzed qualitatively and quantitatively, and the quality of evidence was assessed per the Grading of Recommendations Assessment, Development, and Evaluation methodology. No funding was used.

RESULTS

Our literature review (PROSPERO 2020-CRD42020201241, MEDLINE, EMBASE, Cochrane, Web of Science, January 15, 2020) resulted in 151 studies. Intensive care unit admission was qualitatively not superior for any defined cohort other than by clinical assessment. Poor IS performance was associated with prolonged hospital length of stay, pulmonary complications, and unplanned ICU admission. Noninvasive positive pressure ventilation was associated with 85% reduction in odds of pneumonia ( p < 0.0001) and 81% reduction in odds of mortality ( p = 0.03) in suitable patients without risk of airway loss. Ketamine use demonstrated no significant reduction in pain score but a trend toward reduced opioid use. Epidural and other locoregional analgesia techniques did not affect pneumonia, length of mechanical ventilation, hospital length of stay, or mortality.

CONCLUSION

We do not recommend for or against routine ICU admission. We recommend use of IS to inform ICU status and conditionally recommend use of NIPPV in patients without risk of airway loss. We offer no recommendation for or against ketamine, epidural, or other locoregional analgesia.

LEVEL OF EVIDENCE

Systematic Review/Meta-analysis; Level IV.

Chondroitin sulfate enhances the barrier function of basement membrane assembled by heparan sulfate

Glycosaminoglycans are ubiquitously expressed polysaccharides that are attached to proteoglycans. Here, we showed that ablation of the heparan sulfate (HS) polymerase Ext1 in retinal progenitor cells did not affect initial progression of retinal angiogenesis, but it disrupted the pruning of blood vessels and establishment of arterioles and venules. In the absence of retinal HS, blood vessels were also vulnerable to high oxygen tension in early postnatal stages, which could be rescued by exogenous vascular endothelial growth factor (VEGF), consistent with the role of retinal HS in the fine-tuning of VEGF signaling. Furthermore, we observed that the retinal inner limiting membrane (ILM) was disrupted by deletion of Ext1 in a timing-specific manner, suggesting that retinal HS is required for the assembly but not the maintenance of the basement membrane. Lastly, we showed that further deletion of C4st1, a chondroitin sulfate (CS) sulfation enzyme, did not affect the assembly of the ILM but, when combined with Ext1 deletion, it aggravated the retinal permeability by disrupting the retinal glycocalyx. These results demonstrate an important role of CS and HS in establishing the barrier function of the extracellular matrix.

Ocular Blood Flow in Preterm Neonates: A Preliminary Report

Purpose

Retinopathy of prematurity (ROP) is a vision-threatening complication occurring in pre-term neonates. The standard of care entails regular monitoring by dilated ophthalmoscopy examinations, which entail stress and potential morbidity. In this pilot study, we used plane-wave ultrasound (PWUS) to image, measure, and assess the association of blood-flow velocities in the retrobulbar vessels with ROP stages ranging from stage 0 (immature vessels without ROP) to stage 3.

Methods

Both eyes of 14 preterm neonates at risk for ROP were examined by 18 MHz PWUS. All but two subjects had a follow-up examination. PWUS was acquired for 1.5 seconds at 3000 compound B-scans/sec. Data were postprocessed to form color-flow images and spectrograms depicting flow velocity in the central retinal artery (CRA), central retinal vein (CRV), and the short posterior ciliary arteries (SPCA). Flow parameters derived from spectrograms were compared by ROP stage.

Results

ROP stage was found to correlate with flow velocities. Velocities were significantly elevated with respect to non-ROP eyes in all vessels at stage 3 and in the SPCAs at stage 2.

Conclusions

PWUS measurement of blood flow may provide a quantitative, clinically important, and easily tolerated means for detecting and assessing the risk of ROP in preterm neonates. We speculate that the observed increase in flow velocity results from elevated vascular endothelial growth factor (VEGF) in ROP eyes.

Translational Relevance

PWUS offers a gentle, nonmydriatic method for monitoring neonates at risk for ROP that would complement ophthalmoscopy.

Neurovascular compression of the oculomotor nerve presenting with aberrant reinnervation

Purpose

To report a case of neurovascular compression in a patient presenting with ophthalmic evidence of aberrant reinnervation.

Observation

A 68-year-old woman diagnosed with right partial third nerve palsy with aberrant regeneration. Suspicion was based on isolated clinical features of the right eye, including ptosis, upper eyelid elevation on adduction, mydriasis, exotropia, and hypotropia. Magnetic resonance imaging revealed atrophy of the right oculomotor nerve secondary to neurovascular compression from a prominent right superior cerebellar artery.

Conclusion and importance

This case highlights the importance of utilizing Fast Imaging Employing Steady-state Acquisition (FIESTA) for the diagnosis of oculomotor nerve palsy presenting with evidence of aberrant reinnervation.

Actual Visual Acuity Demands in the Classroom

PURPOSE

To address the knowledge gap regarding the actual acuity requirements needed in typical kindergarten through grade 12 classrooms by determining an actual logarithm of the minimum angle of resolution (logMAR) and contrast sensitivity requirements in a sample of classrooms for kindergarten through grade 12 in New York City.

METHODS

Measurements of classroom dimensions with specific attention to viewing distances were made in public and private school classrooms, at various grade levels from kindergarten through grade 12, in New York City. The dimensions of typical text shown to students on classroom smartboards and whiteboards was measured and the mean and range of logMAR values were calculated for various seating locations within the classrooms. Contrast between text and background was estimated by comparing digital images of actual classroom text to Pelli-Robson contrast sensitivity charts.

RESULTS

Fourteen classrooms in five schools were evaluated. Classroom dimensions varied from 8 × 10 feet to 23 × 23 feet. Mean logMAR values of lower case text on smartboards and whiteboards varied from 0.93 ± 0.29 (range: 0.83 to 1.32) in the center of the front row to 0.46 ± 0.21 (range: 0.10 to 0.79) in the center of the back row (P < .001). Contrast was also variable, being highest for black markers on whiteboards (0.00) and lowest on smartboards (0.15 to 0.60). Neither logMAR nor contrast sensitivity values varied significantly by grade level or school (P > .50 for both).

CONCLUSIONS

The data reveal that logMAR demands and contrast vary substantially from classroom to classroom and within a classroom based on room dimensions and seating. Although generally supporting current acuity-based pediatric vision screening referral guidelines, the data also provide insight into the potential impact of reduced visual acuity and seating location on visual performance in the classroom. These findings suggest the need to develop logMAR and contrast standards that optimize visual content in classrooms while accommodating a wider range of visual capabilities. [J Pediatr Ophthalmol Strabismus. 2021;58(1):48-54.].

Gangrenous appendicitis contained within a Spigelian hernia

A 66-year-old man with abdominal pain had a 5-year-old mass subsequently identified as a Spigelian hernia. Exploratory laparotomy revealed a strangulated and gangrenous appendix contained within the hernia, necessitating an appendectomy. This case highlights the importance of early identification and exploration of this rare hernia, so that early management can prevent the development of more serious and dangerous symptoms.

Securing extraocular muscles in strabismus surgery: effect of cautery on suture strength

An experimental study was performed to evaluate quantitatively the effect of cautery on the tensile strength of sutures commonly used in strabismus surgery. This in vitro study was conducted in a controlled fashion using 6-0 polyglactin 910 suture, two different forms of cautery, and a precision digital force gauge. The results suggest that thermal electrocautery with a wire tip can substantially weaken or break 6-0 polyglactin threads only if direct contact is made, but bipolar cautery at typical ophthalmic surgical settings does not.

Sedation and paralytic use in open abdomen patients-results from the EAST SLEEP Survey

BACKGROUND

Patients with an open abdomen after trauma or emergency surgery may benefit from reduced sedation and chemical paralysis. We studied the effect of attending surgeon experience on sedation depth and paralytic use, as well as enteral nutrition and time between laparotomies.

METHODS

We performed an institutional review board-approved survey (Sedation Level after Emergent ExLap without Primary Fascial Closure) of the senior and active Eastern Association for the Surgery of Trauma membership using Qualtrics (Qualtrics, Inc, Provo, UT). We obtained 393/1,655 responses (23.7%). Spearman's rho was used for ordinal data, and multivariate logistic regression was used to adjust for trauma center level and presence of trainees in the relationship between surgeon experience and use of deep sedation.

RESULTS

Surgeon experience was associated with deep sedation (Richmond Agitation and Sedation Score ≤-3, P = .001) and chemical paralysis (P = .001). Surgeon experience was associated with less concern about delirium and more concern for evisceration as the reason for sedation depth (P = .001) and for paralysis (P = .001). Using multivariate logistic regression, surgeon experience was associated with deep sedation (odds ratio 3.6 [95% confidence interval 1.3, 10.4], P = .017 for ≥20 years; odds ratio 3.5 [95% confidence interval 1.1, 10.4], P = .025 for 15-20 years). Trauma center level was also significant (odds ratio 7.2 for Richmond Agitation and Sedation Score ≤-3 [95% confidence interval 1.7, 31.0], P = .008 for level III/IV versus level I/II). Increased surgeon experience was associated with delay of commencement of enteral feeds until return of bowel function (P = .013). Few respondents indicated willingness to extubate or mobilize open abdomen patients. Experienced surgeons were likely to wait for a defined time rather than for normalization of resuscitation markers to perform the first takeback laparotomy (P = .047) and waited longer between subsequent laparotomies (P = .004).

CONCLUSION

There were significant variations in practice among respondents based on the length of time since their last residency or fellowship, including variations that deviate from current best practice for management of patients with an open abdomen.

Suicide in the Elderly: A Multidisciplinary Approach to Prevention

Suicide in the elderly is a growing problem. The elderly population is increasing, and elderly patients have multiple issues that place them at higher risk of suicidality. These issues include physical illnesses, mental illness, loss of functional status, isolation, and family, financial, and social factors. Access to firearms is another significant risk factor, because elderly patients are more likely to use firearms in suicide attempts; interventions to reduce firearms mortality may save lives. Tackling the difficult problem of suicide in the elderly may require a multidisciplinary, community-based series of interventions.

A novel method to visualise the three-dimensional organisation of the human cerebral cortical vasculature

Current tissue-clearing protocols for imaging in three dimensions (3D) are typically applied to optimally fixed, small-volume rodent brain tissue - which is not representative of the tissue found in diagnostic neuropathology laboratories. We present a method to visualise the cerebral cortical vasculature in 3D in human post-mortem brain tissue which had been preserved in formalin for many years. Tissue blocks of cerebral cortex from two control cases, two Alzheimer's brains and two cases from Alzheimer's patients immunised against Aβ₄₂ were stained with fluorescent Lycopersicon esculentum agglutinin (Tomato lectin), dehydrated and cleared using an adapted three-dimensional imaging of solvent cleared organs (3DISCO) protocol to visualise the vascular endothelium. Tissue was imaged using light sheet and confocal microscopy and reconstructed in 3D using amira software. The method permits visualisation of the arrangement of the parallel penetrating cortical vasculature in the human brain. The presence of four vascular features including anastomosis, U-shaped vessels, spiralling and loops were revealed. In summary, we present a low cost and simple method to visualise the human cerebral vasculature in 3D compatible with prolonged fixation times (years), allowing study of vascular involvement in a range of normative and pathological states.

Securing extraocular muscles in strabismus surgery: laboratory analysis of biomechanical parameters related to the suture

PURPOSE

To investigate the tensile properties of several components used to secure extraocular muscle to sclera in strabismus surgery to determine potential failure points.

METHODS

A digital force gauge measured the tensile strength of intact or damaged 6-0 Vicryl suture (Ethicon, Somerville, NJ), as well as threads tied in a 2-1-1 or 2-1-1-1 surgeon's knot configuration. Human sclera was used to test the resistance to drag of knotted and unknotted 6-0 Vicryl suture thread through partial thickness sclera. Mean values were compared using a t test.

RESULTS

The mean tensile strength of 6-0 Vicryl suture was 623.5 g, but it was markedly reduced by damage from the needle (P < 0.0001) or ophthalmic needle holder (P < 0.0001). The 2-1-1 knots broke at a mean force of 307.6 g, compared with 292.8 g for 2-1-1-1 knots (P = 0.84). Drag through a 2 mm scleral tunnel was 4.6 g, compared to 13.6 g for a 4 mm tunnel (P = 0.011). The force required to pull a knotted suture through a 4 mm scleral tunnel was 254 g for a 2-1-1 knot and 367 g for a 2-1-1-1 knot (P < 0.015).

CONCLUSIONS

Although 6-0 Vicryl possesses adequate tensile strength for muscle fixation, thread damage from a needle or needle holder may cause serious losses in tensile strength. Knot-breaking strength is not significantly increased by adding a fourth throw. Frictional forces of the scleral tunnel are not sufficient to provide muscle stabilization, but the presence of a knot can provide substantial resistance to suture slip into the scleral tunnel.

Evidence-Based Care of Geriatric Trauma Patients

The doubling of the geriatric population over the next 20 years will challenge the existing health care system. Optimal care of geriatric trauma patients will be of paramount importance to the health care discussion in America. These patients warrant special consideration because of altered anatomy, physiology, and the resultant decreased ability to tolerate the stresses imposed by traumatic insult. Despite increased risk for worsened outcomes, nearly half of all geriatric trauma patients will be cared for at nondesignated trauma centers. Effective communication is crucial in determining goals of care and arriving at what patients would consider a meaningful outcome.

Securing extraocular muscles in strabismus surgery: biomechanical analysis of muscle imbrication

An experimental study was performed to quantitatively evaluate the tensile strength of extraocular muscle imbrication as it relates to the positioning of the imbricating suture. The study was conducted in a controlled fashion using fresh ex vivo pig eyes with extraocular muscles attached and a precision digital force gauge. The study provides clinically translatable data to inform surgical technique regarding secure muscle imbrication. Results suggest that imbrications performed 0.5 mm or less from the cut muscle edge or 0.5 mm or less from the lateral margin may be prone to tensile failure.

Head, Neck, and Shoulder Injuries in Ice Hockey: Current Concepts

Ice hockey is a fast-paced contact sport that is becoming increasingly popular in North America. More than 1 million men, women, and juniors are playing hockey in the United States and Canada. With players colliding forcefully with one another and with the boards surrounding the ice, injury rates are among the highest in all of competitive sports. Physicians caring for a hockey team should be aware of the more common injuries, involving the head, the neck, and the shoulder. In this review, we discuss evaluation and treatment of these hockey injuries, return to play, and, where applicable, prevention strategies.

Graded Marginal Recession: A Surgical Technique to Correct Small Angle Vertical Deviations

PURPOSE

To describe a novel muscle recession technique to surgically correct small angle vertical deviations in symptomatic adults with fusion potential.

METHODS

A novel technique involving a graded recession of the medial and lateral poles of a vertical rectus muscle, combined with graded medial and lateral tenotomy of the muscle, was used to treat small vertical deviations. A surgical nomogram was developed based on the configuration of the procedure and its predicted effects. Four patients with small angle hypertropia ranging from 1 to 5 prism diopters (PD) underwent the graded marginal recession procedure and were observed for up to 3 years.

RESULTS

Three of the four patients had successful correction of their strabismus and resolution of diplopia, with no complications or induced incomitance. One patient was initially orthotropic but showed a 2 PD regression 1 month postoperatively, eventually requiring additional surgery to achieve stable orthotropia.

CONCLUSIONS

The graded marginal recession can be safely and effectively used to correct very small vertical deviations in adults with fusion potential. A surgical nomogram can be created to guide predicted corrections in increments of less than 0.5 PD.

Insulin resistance increases before ventilator-associated pneumonia in euglycemic trauma patients

BACKGROUND

Hyperglycemia caused by stress-induced insulin resistance is associated with both infection and mortality in critically injured patients. The onset of infection may increase stress-induced insulin resistance, leading to hyperglycemia. Hyperglycemia has been shown to precede the diagnosis of ventilator-associated pneumonia (VAP) in critically injured adults and has been suggested to have potential diagnostic importance. However, glycemic control (GC) protocols in critically ill patients limit the development of hyperglycemia despite increasing insulin resistance. Our computer-assisted GC protocol achieves excellent GC, limiting infection-related hyperglycemia while capturing prospectively all glucose values, insulin infusion rates, and the multiplier (M) used to calculate the insulin rate. We hypothesized that surrogate measures of insulin resistance, the insulin infusion rate and multiplier M, would increase prior to the clinical suspicion of VAP, even in euglycemic critically injured patients.

METHODS

All critically injured patients (2,656) on the computerized glycemic control protocol were included in the analysis and categorized by those developing VAP and those without pneumonia on days 3-10 of their intensive care unit (ICU) stay. Median blood glucose concentration (BG), insulin infusion rate (IDR), and multiplier (M) [Insulin Drip Rate=M*(BG-60)] were determined for VAP patients (n=329) and non-infected ventilated (NIV) patients (n=2,327) on each day of mechanical ventilation. The day of VAP diagnosis according to U.S. Centers for Disease Control and Prevention (CDC) criteria was defined as day zero and VAP patients matched with NIV patients according to ventilator day from -10 to +10. Comparisons were conducted using the Mann-Whitney U test.

RESULTS

Baseline characteristics between VAP and NIV groups did not differ. Measures of insulin resistance increased from the time of injury in both groups. Patients with VAP had significantly greater change in both measures of insulin resistance, IDR and M, in the 48 hours preceding the diagnosis of VAP. These changes occurred despite the fact that the computer-assisted GC protocol achieved lower glucose values in VAP patients for the majority of study days.

CONCLUSIONS

Measures of insulin resistance increase in the two days prior to the clinical suspicion of VAP for critically injured patients on the GC protocol. These changes occur despite the protocol maintaining euglycemia. This data suggests that markers of insulin resistance may provide clinically useful information in the early diagnosis of VAP.

Insulin Resistance in Critically Injured Adults: Contribution of Pneumonia, Diabetes, Nutrition, and Acuity

PURPOSE

Changes in insulin resistance (IR) cause stress-induced hyperglycemia after trauma, but the numerous factors involved in IR have not been delineated clearly. We hypothesized that a statistical model could help determine the relative contribution of different clinical co-variates to IR in critically injured patients.

PATIENTS AND METHODS

We retrospectively studied 726 critically injured patients managed with a computer-assisted glycemic protocol at an academic level I trauma center (639 ventilated controls without pneumonia (VWP) and 87 patients with ventilator-associated pneumonia (VAP). Linear regression using age, gender, body mass index (BMI), diabetes mellitus, pneumonia, and glycemic provision was used to estimate M, a marker of IR that incorporates both the serum blood glucose concentration (BG) and insulin dose.

RESULTS

Increasing M (p<0.001) was associated with age (1.62%; 95% confidence interval [CI] 1.27%-1.97% per decade), male gender (9.78%; 95% CI 8.28%-12.6%), BMI (4.32% [95% CI 4.02%-4.62%] per 5 points), diabetes mellitus (21.2%; 95% CI 19.2%-23.2%), pneumonia (10.9%; 95% CI 9.31%-12.6%), and glycemic provision (27.3% [95% CI 6.6%-28.1%] per 100 g of glucose). Total parenteral nutrition was associated with a decrease in M of 10.3%; 95% CI 8.52%-12.1%; p<0.001.

CONCLUSIONS

Clinical factors can be used to construct a model of IR. Prospective validation might enable early detection and treatment of infection or other conditions associated with increased IR.

Intrinsic Klebsiella pneumoniae Contamination of Liquid Germicidal Hand Soap Containing Chlorhexidine

We describe intrinsic contamination with Klebsiella pneumoniae occurring during the manufacture of germicidal hand soap, labeled as containing 2% chlorhexidine, used throughout a 350-bed community medical center. A 3-year retrospective study failed to find evidence of increased incidence of clinical isolates of this strain.

Hyperoxia causes regression of vitreous neovascularization by downregulating VEGF/VEGFR2 pathway

PURPOSE

Neovascularization (NV) is a sight-threatening complication of retinal ischemia in diabetes, retinal vein occlusion, and retinopathy of prematurity. Current treatment modalities, including laser photocoagulation and repeated intraocular injection of VEGF antagonists, are invasive and not always effective, and may carry side effects. We studied the use of hyperoxia as an alternative therapeutic strategy for regressing established vitreous NV in a mouse model of oxygen-induced ischemic retinopathy.

METHODS

Hyperoxia treatment (HT, 75% oxygen) was initiated on postnatal day (P)17 after the onset of vitreous NV. Immunohistochemistry and quantitative PCR were used to assess retinal vascular changes in relation to apoptosis, and expression of VEGFR2 and inflammatory molecules. Effects of intravitreal injections of VEGF-A, VEGF-E, PlGF-1, and VEGF trap were also studied.

RESULTS

HT selectively reduced NV by 70% within 24 hours. It robustly increased the level of cleaved caspase-3 in the vitreous NV between 6 and 18 hours and promoted infiltration of macrophage/microglial cells. The HT-induced apoptosis was preceded by a significant reduction in VEGFR2 expression within the NV and an increase in VEGFR2 within the surrounding neural tissue. Intravitreal VEGF-A and VEGF-E (VEGFR2 agonist) but not PlGF-1 (VEGFR1 agonist) prevented HT-induced apoptosis and regression of NV. In contrast, VEGF trap and VEGFR2 blockers mimicked the effect of HT. However, intravitreal VEGF trap induced increases in inflammatory molecules while HT did not have such unwanted effect.

CONCLUSIONS

HT may be clinically useful to specifically treat proliferative NV in ischemic retinopathy.

Abstract P4-11-06: Automatic referral to genetic counseling for identification of BRCA1/2 mutations: a pilot program at Norton Cancer Institute, Louisville, KY

BACKGROUND: Identifying a hereditary cancer syndrome has the potential to significantly impact a patient's treatment and long-term management, as well as prevent future malignancies among relatives. Therefore, referral of patients appropriate for genetic counseling and testing is critical. Providers traditionally initiate patient referral; however, this can lead to inconsistent referrals and results in failure to refer more than 50% of appropriate individuals, according to recent studies. In an attempt to address these quality issues, we developed an automatic referral program using the National Comprehensive Cancer Network guidelines, which was approved through our cancer committee and implemented 10/1/10. This pilot was conducted within a genetic counseling program staffed by board certified genetic counselors and associated with a private, multi-disciplinary oncology practice that is part of an American College of Surgeons accredited Network Cancer Center. Our Cancer Center is part of a five-hospital integrated healthcare system and a part of the National Cancer Institute Community Cancer Centers Program network.

METHODS: We conducted weekly reviews of oncology patients scheduled for upcoming appointments to identify individuals diagnosed with breast cancer before age 50 or with ovarian, fallopian, or primary peritoneal cancer at any age. Patients previously referred to our genetic counseling program were excluded. Providers were notified weekly of their patients identified via this program, with the option to decline referral. We undertook a retrospective review of the outcomes of individuals identified from 10/1/10 through 10/1/11, with follow up as of 6/1/12. IRB approval was obtained through the University of Louisville.

RESULTS: We identified 521 patients for referral, 24 (4.6%) of whom were declined by a provider, resulting in 497 referrals. Three hundred forty one (69%) referrals had breast cancer and 156 (31%) had other malignancies. Of referrals, 139 (28%) have been seen, 223 (45%) have declined, and 135 (27%) are in process. Testing was pursued by 108 (78%) of referrals seen, all of whom had BRCA1/2 testing and 5 (4.6%) of whom had additional testing. We identified 11 (10%) individuals with a BRCA1/2 mutation. An additional 17 (16%) individuals who completed testing were counseled to consider enhanced surveillance in the absence of a confirmed hereditary cancer syndrome. The total number of first degree relatives with potential to benefit from this program is 62 among individuals with a BRCA1/2 mutation and 86 among individuals without a confirmed hereditary cancer syndrome.

CONCLUSIONS: Initiation of an automatic genetic counseling referral program in the setting of a large oncology practice is feasible and has the potential to identify individuals with a BRCA1/2 mutation who might otherwise go undetected. Few providers object to referral, and the majority of patients are receptive to referral. The impact of this program extends beyond those identified with a BRCA1/2 mutation. This project was funded in part with federal funds: NCI, NIH Contract No. HHSN261200800001E.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P4-11-06.

Neuroprotection from retinal ischemia/reperfusion injury by NOX2 NADPH oxidase deletion

PURPOSE

The aim of this study was to determine whether NOX2, one of the homologs of NADPH oxidase, plays a role in neuronal cell death during retinal ischemia.

METHODS

Ischemia reperfusion (I/R) injury was generated in C57/BL6 and NOX2(-/-) mice by increasing the intraocular pressure (IOP) to 110 mm Hg for 40 minutes followed by reperfusion. Quantitative PCR and Western blot analysis were performed to measure NOX2 expression. Reactive oxygen species (ROS) formation was assessed by dihydroethidium imaging of superoxide formation and Western blot analysis for tyrosine nitration. TUNEL assay was performed to determine cell death at 3 days after I/R. Survival of neurons within the ganglion cell layer (GCL) was assessed at 7 days after I/R by confocal morphometric imaging of retinal wholemounts immunostained with NeuN antibody. Activation of mitogen-activated protein kinases and nuclear factor κB (NF-κΒ) was measured by Western blot analysis.

RESULTS

NOX2 mRNA and protein and ROS were significantly increased in wild-type I/R retinas. This effect was associated with a 60% decrease in the number of GCL neurons and a 10-fold increase in TUNEL-positive cells compared with the fellow sham control eyes. Phosphorylation of ERK and NF-κB was significantly increased in wild-type I/R retinas. Each of these effects was markedly attenuated in the NOX2(-/-) retina (P < 0.01).

CONCLUSIONS

These data demonstrate that the deletion of NOX2 can reduce I/R-induced cell death and preserve retinal GCL neurons after I/R injury. The neuronal cell injury caused by I/R is associated with the activation of ERK and NF-κB signaling mechanisms.

Hyperoxia therapy of pre-proliferative ischemic retinopathy in a mouse model

PURPOSE

To investigate the therapeutic use and mechanisms of action of normobaric hyperoxia to promote revascularization and to prevent neovascularization in a mouse model of oxygen-induced ischemic retinopathy.

METHODS

Hyperoxia treatment (HT, 40%-75% oxygen) was initiated on postnatal day (P) 14 during the pre-proliferative phase of ischemic retinopathy. Immunohistochemistry, ELISA, and quantitative PCR were used to assess effects on retinal vascular repair and pathologic angiogenesis in relation to glial cell injury, VEGF protein, and mRNA levels of key mediators of pathologic angiogenesis. Effects of intravitreal injections of VEGF and the VEGF inhibitor VEGFR1/Fc fusion protein were also studied.

RESULTS

Administration of HT during the ischemic pre-proliferative phase of retinopathy effectively accelerated the process of revascularization while preventing the development of vitreous neovascularization. HT enhanced the formation of specialized endothelial tip cells at the edges of the repairing capillary networks and blocked the overexpression of several molecular mediators of angiogenesis, inflammation, and extracellular proteolysis. HT markedly reduced the reactive expression of GFAP in Müller cells and improved the morphology of astrocytes in the avascular region of the retina. Exogenous VEGF administered into the vitreous on P14 was not sufficient to cause vitreous neovascularization in the HT mice. Injection of the VEGF antagonist VEGFR1/Fc blocked both pathologic and physiological angiogenesis and did not rescue astrocytes.

CONCLUSIONS

HT may be clinically useful to facilitate vascular repair while blocking neovascularization in the pre-proliferative stage of ischemic retinopathy by correcting a broad range of biochemical and cellular abnormalities.

Reaching Underserved Women with Mammography: 15 month experience with a Mobile Prevention Unit and Prevention Program

Objective: There is much debate regarding the efficacy of mammography screening in women &lt;50. No cost and low cost service providers may be required to target screening to the population at highest risk in order to maximize utility of resources. We sought to describe outcomes of women &gt;40 undergoing mammography screening in underserved areas through a mobile unit and prevention program affiliated with a large network cancer program in Louisville, Kentucky.

Methods: We conducted a retrospective review of women undergoing mammography during the period 3/08-6/09. Locations determined to be high risk by GIS analysis, income and cancer incidence. Analyses included: descriptive analyses, calculation of odds ratios and confidence intervals and regression analyses.

Results: Of the 1702 women, 735 (43%) were white, 884 (52%) were African American, 54 (3%) other and 236 (14%) Hispanic/Latina. The mean age was 54 (std.dev. 9.4). Twenty-eight percent of the women (471/1702) had either never had a mammogram or not had one in 5 years. Fifty-one percent were uninsured. Of the 1702 women, 662(39%) were between the ages of 40-49 (Group A) and 1040 (61%) were &gt;49 (Group B). The majority of women resided in high risk areas (74% Group A, 51% Group B). Twelve percent (206/1702) of the mammograms were abnormal and required follow up. Women in Group A were 1.4 times more likely than women in Group B to have a screening mammogram classified as abnormal (OR 1.4 95% CI 1.05-1.88). Four women were diagnosed with cancer in group A (0.6%) and 9 in group B (0.8%), P = ns. The median age of women with cancer was 52, mean = 58, range 42-83, (std. dev. 12.5). The overall follow up rate was 92%. All women with cancer received treatment. Logistic regression analysis demonstrated women of African American race and women who had never been screened were more likely to have abnormal results (P &lt; 0.0001 and P = 0.03 respectively).

Conclusion: Our targeted approach of community based screening was successful in identifying a subpopulation of women who are not regularly screened and are at risk for abnormal screening mammograms and breast cancer. Further studies are needed to determine if recommendations for screening should be based on factors other than age.

The uncut Roux-en-Y with jejunal pouch: a new reconstruction technique for total gastrectomy

BACKGROUND

Roux Stasis Syndrome is a well-known complication after Roux-en-Y reconstruction. It has been hypothesized that reconstruction with an uncut Roux limb and jejunal pouch after total gastrectomy would preserve unidirectional intestinal myoelectrical activity, improve postoperative weight gain and nutritional parameters, and diminish Roux Stasis Syndrome in canines.

METHODS

A total gastrectomy was performed, and 2 methods were used for reconstruction: Roux-en-Y esophagojejunostomy (RY) was performed on 5 canines (control), and the uncut Roux-en-Y with a jejunal pouch (URYJP) was performed on 5 other canines (experimental). The canines were monitored for 10 weeks postoperatively. Serial weight and nutritional parameters were measured. Emptying profiles and motility studies were performed in the fasting and postprandial states.

RESULTS

Ten weeks after operation, the URYJP group had significantly improved nutritional parameters, including weight, total protein, albumin, hemoglobin, serum total iron binding capacity, and serum IgA, IgG, and IgM. The emptying times for both groups were similar, with an increase of disordered propagation of the jejunal pacesetter potential in the RY group. The aboral propagation occurred more frequently in the URYJP group during fasting and after feeding (98% +/- 1% vs 39% +/- 16%; P = .02, and 99% +/- 1% vs 43% +/- 18%; P = .03). The sites of luminal occlusions were intact in the URYJP group at 10 weeks.

CONCLUSIONS

The combination of jejunal pouch and uncut Roux limb improved overall nutritional parameters when compared with the traditional Roux-en-Y, while preserving aboral propagation of jejunal pacesetter potentials.

Destruction of human retinoblastoma after treatment by the E variant of encephalomyocarditis virus

The oncolytic effects of encephalomyocarditis (EMC) virus were examined in human retinoblastoma cell (Y79) cultures which were infected with 10(4 )tissue culture infectious doses (TCIDs) of the E variant of EMC (EMC-E) virus. The TCIDs were used to titer the maximum effect of EMC virus on L-929 cells. In-vitro studies showed 90% cytopathic effect (CPE) at 24 h and 100% CPE at 52 h. The CPE was used to observe pathologic effects of the cells. In-vivo studies employing human retinoblastoma grown as a tumor in nude mice, revealed degeneration of 80% of the tumor cells at 3 days and total destruction at 4 days following inoculation with the EMC-E virus. The virus is highly neurotropic in mice, but is usually not pathogenic in man. These studies suggest a possible new direction in the treatment of retinoblastoma and other malignant tumors using the viral technology.

Hyperoxia induces retinal vascular endothelial cell apoptosis through formation of peroxynitrite

Hyperoxia exposure induces capillary endothelial cell apoptosis in the developing retina, leading to vaso-obliteration followed by proliferative retinopathy. Previous in vivo studies have shown that endothelial nitric oxide synthase (NOS3) and peroxynitrite are important mediators of the vaso-obliteration. Now we have investigated the relationship between hyperoxia, NOS3, peroxynitrite, and endothelial cell apoptosis by in vitro experiments using bovine retinal endothelial cells (BREC). We found that BREC exposed to 40% oxygen (hyperoxia) for 48 h underwent apoptosis associated with activation of caspase-3 and cleavage of the caspase substrate poly(ADP-ribose) polymerase. Hyperoxia-induced apoptosis was associated with increased formation of nitric oxide, peroxynitrite, and superoxide anion and was blocked by treatment with uric acid, nitro-L-arginine methyl ester, or superoxide dismutase. Analyses of the phosphatidylinositol 3-kinase/Akt kinase survival pathway in cells directly treated with peroxynitrite revealed inhibition of VEGF- and basic FGF-induced activation of Akt kinase. These results suggest that hyperoxia-induced formation of peroxynitrite induces BREC apoptosis by crippling key survival pathways and that blocking peroxynitrite formation prevents apoptosis. These data may have important clinical implications for infants at risk of retinopathy of prematurity.

VEGF differentially activates STAT3 in microvascular endothelial cells

Increased VEGF expression is found in several pathologies characterized by abnormal angiogenesis. Previous studies have shown that the transcription factor STAT3 mediates VEGF gene transcription and its activation. In this study, Western analysis and confocal immunocytochemistry were used to examine STAT3 activation in retinal microvascular endothelial cells (BREC). We found that VEGF rapidly induces STAT3 tyrosine phosphorylation and nuclear translocation. Immunoprecipitation studies also showed that VEGF forms a complex with VEGFR2 only in BREC and not in aortic macrovascular endothelial cells (BAEC). In addition, quantitative real-time RT-PCR analysis of VEGF-induced VEGF expression showed a significant increase in specific mRNA formation only in BREC and not in BAEC, and this effect was significantly reduced by antisense-mediated reduction of STAT3 expression. Furthermore, studies conducted in human dermal microvascular endothelial cells (HDMEC) showed that, in this endothelial cell type, VEGF autocrine expression is also accompanied by STAT3 activation as in BREC. In this study we showed that VEGF can differentially induce STAT3 activation in micro- versus macro-vascular endothelial cells and that this effect is linked to VEGFR2/STAT3 complex formation, which correlates with VEGF autocrine ability to stimulate its own gene expression.

Chlorhexidine resistance in antibiotic-resistant bacteria isolated from the surfaces of dispensers of soap containing chlorhexidine

Bacterial contamination with pan-resistant Acinetobacter and Klebsiella, multidrug-resistant Pseudomonas, and methicillin-resistant Staphylococcus aureus (MRSA) was noted on the surfaces of dispensers of hand soap with 2% chlorhexidine. Gram-negative isolates could multiply in the presence of 1% chlorhexidine. In contrast, MRSA was inhibited in vitro by chlorhexidine at concentrations as low as 0.0019%.

Cervical cancer--the impact of clinical presentation, health and race on survival

This study evaluated the association of race, comorbid illness, insurance status, and other prognostic factors on treatment and survival of patients with invasive carcinoma of the cervix, using as its methodology a retrospective study of patients with invasive carcinoma of the cervix treated from 1991 to 1998 at the University of Maryland. Of 161 such patients, 153 met the study criteria. Of these 153 women, 83 (54%) were African Americans and 70 (46%) were white. The mean (+/- SE) age of African American women was 52 +/- 1.8 years and that of white women was 50 +/- 1.8 years. African American women were more likely to present with stages II-IV disease (P = 0.01) and, as a consequence, underwent radiation therapy rather than surgery (P = 0.04). The survival of African American women with stage I-II disease was significantly lower than for white women. In the final regression model, stage III-IV disease (hazard ratio 3.2, 95% (CI 1.7, 6.1) African American race, (hazard ratio 1.9; 95% CI 1.0, 3.3) and comorbid illnesses (hazard ratio 2.3; 95% CI 1.3-4.0) were associated with poor survival. Adverse outcomes of African American women with cervical cancer persist after adjustment for stage of disease and other factors and are particularly apparent in stage I-II disease. The role of comorbid illness is deserving of further study.

Effects of sustained hyperoxia on revascularization in experimental retinopathy of prematurity

PURPOSE

To investigate the effects of prolonged hyperoxia on vascular recovery and glia survival after experimentally induced retinopathy of prematurity (ROP) in the mouse.

METHODS

The effects of hyperoxia on revascularization and vitreous neovascularization were compared between mice raised in 75% oxygen from postnatal day (P)7 to P12, followed by room air recovery and mice raised in 75% oxygen from P7 to P27. The status of astrocytes and Müller cells was evaluated by glial fibrillary acidic protein (GFAP) immunohistochemistry on retinal wholemounts and serial sections. A window of susceptibility to oxygen-induced vaso-obliteration was defined by comparing the extent of retinal vaso-obliteration resulting from 2 days of hyperoxia beginning on P7, P9, P11, P13, or P15.

RESULTS

Oxygen-induced vaso-obliteration of retinal capillaries was limited to the period between birth and P15. Paradoxically, revascularization was markedly accelerated and neovascularization markedly reduced in mice maintained in prolonged hyperoxia (P7-P27) compared with mice recovering in room air. The extended use of 75% oxygen during the recovery period was associated with preservation of astrocytes and Müller cells in the avascular retina.

CONCLUSIONS

The antiangiogenic effect of hyperoxia on retinal capillaries is strongly dependent on postnatal age. A protocol of continuous 75% supplemental oxygen accelerates recovery of inner retinal vasculature and prevents vitreous neovascularization, by a mechanism that may involve preservation of inner retinal glia.

Human papillomavirus absence predicts normal cervical histopathologic findings with abnormal papanicolaou smears: a study of a university-based inner city population

INTRODUCTION

We studied the role of human papillomavirus (HPV) typing in predicting cervical dysplasia in women with abnormal Papanicolaou (Pap) test results.

STUDY DESIGN/METHODS

A university colposcopy clinic-based consecutive sample of 179 women completed a questionnaire and underwent colposcopy, HPV typing (Hybrid Capture System HPV DNA Assay II; Digene Diagnostics, Gaithersburg, MD, USA), and biopsy (if indicated).

RESULTS

No severe dysplasia was observed in women with low-risk HPV or in women with negative HPV test results who had a low-grade abnormality on the Pap test. High-risk (HR) HPV was present in every case of severe dysplasia on biopsy. The cumulative odds risk for cervical dysplasia was 1.11 in HIV(+) women with low-grade squamous intraepithelial lesion on the Pap test who were older than 21 years of age and HPV-HR(+).

CONCLUSIONS

In the population studied, HPV typing is a valuable adjunct to a low-grade abnormality on the Pap test in predicting the absence of cervical dysplasia on biopsy. Larger prospective population-based studies are needed to study the role of HPV as a negative predictor of disease in cervical dysplasia.

Health care cost and utilization project analysis of comorbid illness and complications for patients undergoing hysterectomy for endometrial carcinoma

OBJECTIVE

The objective was to study the association of race, comorbid illness, and lymph node dissection (LND) with complications in patients undergoing hysterectomy for endometrial carcinoma.

METHODS

The Health Care Cost Utilization Project analysis studied women undergoing hysterectomy for endometrial carcinoma in 1996. Chi-square and Student t tests were used to determine differences in means or proportions. Linear, stepwise, and three-stage regression analyses were used to build predictive models for charges and lengths of stay (LOS).

RESULTS

The mean age of the 5730 patients was 64.5 (standard deviation, 12.37); 72% of the patients were white, 5% were African American, and 23% were classified as "other." Ninety percent underwent total abdominal hysterectomy, 5% total vaginal hysterectomy (TVH), 4% radical abdominal hysterectomy, and 1% TVH/laparoscopy. Thirty-eight percent also underwent LND. Lymph node dissection was performed more frequently at teaching hospitals (P = 0.0000) and was associated with more complications. Comorbid illness (i.e., diabetes, heart disease) was documented in 51% of admissions, and > or = 1 comorbidity was documented in 21.5%. African Americans were more likely to have one or more comorbid illnesses, underwent more LNDs (P = 0.02), suffered more complications (P = 0.0001), and were more likely to die in the hospital compared with whites or others (P = 0.000). Although LND, complications, and longer LOS were more likely to occur in teaching hospitals (P = 0.0005), total charges and inpatient death were not higher in teaching hospitals.

CONCLUSIONS

The higher frequency of comorbid illness, complications, LND, and inpatient death in African Americans reflects severity of medical illness and cancer in these patients. Teaching hospital admission was associated with more complications and longer LOS, but not a higher death rate.

Orbital cellulitis due to occult orbital lymphangioma

A 12-year-old female patient with atypical orbital and periorbital cellulitis was found to have an occult lymphangioma of the orbit. Recognition of this entity provided an explanation for the atypical features of the case and guided appropriate medical management.

Reduced severity of oxygen-induced retinopathy in eNOS-deficient mice

PURPOSE

Exposure of premature human infants to hyperoxia results in the obliteration of developing retina capillaries, leading to a vision-threatening retinopathy termed retinopathy of prematurity (ROP). The authors hypothesized that this process may be mediated in part by endothelial nitric oxide (NO)-derived oxidants such as peroxynitrite and tested this hypothesis in a mouse model of ROP.

METHODS

Normal mice, mice treated with the nitric oxide synthase (NOS) inhibitor N:(G)-nitro-L-arginine (L-NNA), and knockout mice carrying a homozygous targeted disruption of the gene for endothelial NOS (eNOS) were studied in an experimental model of ROP. Retinas were compared for extent of capillary obliteration in hyperoxia, vascular endothelial growth factor (VEGF) expression, nitrotyrosine formation, and vitreous neovascularization.

RESULTS

Oxygen-induced retinal vaso-obliteration was significantly reduced by L-NNA treatment (43% decrease from controls). The eNOS-deficient mice showed a similar reduction in vaso-obliteration (46% decrease from controls), and vitreous neovascularization was also substantially reduced (threefold decrease). Retinal nitrotyrosine formation, a measure of in situ peroxynitrite modification of proteins, was significantly elevated in normal mice during hyperoxia, in a spatial and temporal pattern consistent with a role in oxygen-induced vaso-obliteration. This was not seen in eNOS-deficient mice. VEGF expression was similar in both groups of mice, although suppression in hyperoxia was slightly blunted in eNOS-deficient mice.

CONCLUSIONS

These data suggest a role for NO and peroxynitrite in the pathogenesis of ROP. Therapies aimed at modulation of eNOS activity may have therapeutic potential for preventing ROP.

Repeat cervical cytology at the time of colposcopy. Is there an added benefit?

OBJECTIVE

To determine if repeating the Pap smear (PS) at colposcopy offers added benefit in the detection of cervical squamous intraepithelial lesions (SILs).

STUDY DESIGN

Eight hundred fifty-two women were subjects of this study. Patients with cervical SIL were defined as women with SIL on the repeat PS, or SIL on the colposcopic cervical biopsy (bx) or a negative repeat PS and bx but confirmed SIL on both the previous and follow-up PS or bx. The sensitivities of repeat PS and bx in detecting SIL were calculated. The chi 2 test was used to assess statistical significance. The total cost of repeating the PS was calculated by multiplying the total number of patients (852) by the estimated cost of a single PS ($25).

RESULTS

The sensitivities of repeat PS, bx and PS/bx combined were .89, .69 and .92 for low grade SIL (LSIL) and .74, .77 and .98 for high grade SIL (HSIL), respectively (P < .0001). Sixteen percent of the HSIL and 28% of the LSIL cases were diagnosed on repeat PS only (negative bx). If repeat PS was omitted, $21,300 would have been saved.

Vascular endothelial growth factor activates STAT proteins in aortic endothelial cells

Vascular endothelial growth factor (VEGF) intracellular signaling in endothelial cells is initiated by the activation of distinct tyrosine kinase receptors, VEGFR1 (Flt-1) and VEGFR2 (Flk-1/KDR). Because the tyrosine kinase-dependent transcription factors known as STAT (signal transducers and activators of transcription) proteins are important modulators of cell growth responses induced by other growth factor receptors, we have determined the effects VEGF of on STAT activation in BAEC (bovine aortic endothelial cells). Here, we show that VEGF induces tyrosine phosphorylation and nuclear translocation of STAT1 and STAT6. VEGF also stimulates STAT3 tyrosine phosphorylation, but nuclear translocation does not occur. We found that placenta growth factor, which selectively activates VEGFR1, has no effect on the STATs. However, upon VEGF stimulation, STAT1 associates with the VEGFR2 in a tyrosine kinase-dependent manner, indicating that VEGF-induced STAT1 activation is mediated primarily by VEGFR2. Thus, our study shows for the first time that VEGF activates the STAT pathway through VEGFR2. Because the growth-promoting activity of VEGF depends upon VEGFR2 activation, these findings suggest a role for the STATs in the regulation of gene expression associated with the angiogenic effects of VEGF.

Cervical cancer outcomes analysis: impact of age, race, and comorbid illness on hospitalizations for invasive carcinoma of the cervix

OBJECTIVE

The aim of this study was to evaluate the association of age, race, and comorbid illness with procedures and complications in hospitalized patients with invasive carcinoma of the cervix in a statewide population-based database over a 3-year period.

METHODS

Hospitalizations were classified into homogeneous subgroups based on a diagnosis of invasive cervical cancer. Cancer-related complications and comorbid diseases were evaluated. chi(2) and t tests determined differences in means or proportions. Linear regression techniques were applied to build models for hospitalization charges and lengths of stay (LOS).

RESULTS

There were 1009 admissions. The mean age was 49.5, with a median age of 46 (21-100, SD 15.4). Of the total, 606/1009 (60%) were white, 354/1009 (35%) were African-American (AA), and 5% were "other" races. AAs were more likely to have Medicaid or be uninsured (44% vs 23%, P = 0. 001) and were more likely to be admitted for an emergency (unadjusted odds ratio (OR) = 1.6; 1.2-2.2), to have a comorbid illness (P = 0.001), to be admitted for a cancer-related complication (P = 0.036), to be admitted for a transfusion (P = 0. 01), and to be admitted for radiation therapy rather than surgery (P = 0.001). The following were associated with LOS and higher hospital costs: emergency admissions for complications of cancer, comorbid illness, and older age.

CONCLUSIONS

Racial differences exist in patterns of admission, type of therapy, and severity of illness; however, there were no differences in charges or LOS for similar procedures. The large percentage of African-Americans uninsured or insured by government-supported programs indicates the potential impact of public policy on the care of these patients. Socioeconomic status rather than phenotypic appearance may be a more important determinant of outcome.

Pharmacokinetic and pharmacodynamic study of the combination of docetaxel and topotecan in patients with solid tumors

PURPOSE

The sequence in which chemotherapeutic agents are administered can alter their pharmacokinetics, therapeutic effect, and toxicity. We evaluated the pharmacokinetics and pharmacodynamics of docetaxel and topotecan when coadministered on two different sequences of administration.

PATIENTS AND METHODS

On cycle 1, docetaxel was administered as a 1-hour infusion at 60 mg/m(2) without filgrastim and at 60, 70, and 80 mg/m(2) with filgrastim on day 1, and topotecan was administered at 0.75 mg/m(2) as a 0.5-hour infusion on days 1 to 4. On cycle 2, topotecan was administered on days 1 to 4, and docetaxel was administered on day 4. Cycles were repeated every 21 days. Blood samples for high-performance liquid chromatography measurement of docetaxel (CL(DOC)) and topotecan (CL(TPT)) total clearance were obtained on day 1 of cycle 1 and day 4 of cycle 2. CL(DOC) and CL(TPT) were calculated using compartmental methods.

RESULTS

Mean +/- SD CL(DOC) in cycles 1 and 2 were 75.9 +/- 79.6 L/h/m(2) and 29.2 +/- 17.3 L/h/m(2), respectively (P: <.046). Mean +/- SD CL(TPT) in cycles 1 and 2 were 8.5 +/- 4.4 L/h/m(2) and 9.3 +/- 3.4 L/h/m(2), respectively (P: >. 05). Mean +/- SD neutrophil nadir in cycles 1 and 2 were 4,857 +/- 6, 738/microL and 2,808 +/- 4,518/microL, respectively (P: =.02).

CONCLUSION

Administration of topotecan on days 1 to 4 and docetaxel on day 4 resulted in an approximately 50% decrease in docetaxel clearance and was associated with increased neutropenia.

Augmented Hummelsheim procedure for paralytic strabismus

PURPOSE

To report a modification of the Hummelsheim procedure for use in the management of paralytic strabismus.

METHODS

Eight patients with paralytic strabismus secondary to third nerve palsy (n=1), sixth nerve palsy (n=3), combined cranial nerve palsy (n=1), or extraocular muscle damage (n=3) were treated using a modification of the Hummelsheim transposition procedure. The procedure involves half-tendon transpositions of the adjacent rectus muscles to the insertion of the paralyzed muscle, coupled with resection of the transposed halves. Further augmentation was achieved by surgical or pharmacologic weakening of the ipsilateral (n=6) or contralateral (n=1) antagonist. One patient underwent the procedure bilaterally. All patients underwent at least 6 weeks of follow-up.

RESULTS

The mean preoperative primary position deviation in the seven unilateral cases was 54 prism diopters (delta) (range: 25-85 delta). Preoperative forced ductions were positive in four cases. Resections varied from 4-8 mm. Ipsilateral antagonist recession varied from 0-14 mm. The mean change was 52 delta (range: 25-85 delta). Five cases were aligned within 15 delta of orthotropia at 6 weeks. No cases of anterior segment ischemia or induced vertical deviation were noted.

CONCLUSION

The modified Hummelsheim procedure appears capable of correcting large angles of strabismus associated with muscle palsy of various etiologies. It is safe, amenable to adjustable sutures, and relatively tissue- and vessel-sparing. Additional study is required to understand more fully the procedure's component effects and its interaction with ocular rotation.

Discordant retinoblastoma in monozygotic twins

PURPOSE

We report cases of discordant retinoblastoma in twins confirmed to be monozygotic by DNA analysis.

METHODS

Twin A demonstrated severe, bilateral, multifocal retinoblastoma, which was recalcitrant to external beam irradiation and chemoreduction. Twin B has not demonstrated retinoblastoma. DNA analysis was performed with polymorphic microsatellite markers to confirm monozygosity. Single-stranded conformation polymorphism and Southern blot analysis of the retinoblastoma gene were performed.

RESULTS

Molecular genetic analyses confirmed monozygosity but failed to disclose a retinoblastoma gene mutation in either twin.

CONCLUSIONS

The extreme phenotypic discordance may best be explained by an unidentified, postzygotic retinoblastoma gene mutation in early embryonic development of the affected twin.