Comparing Prophylactic Versus Threshold-Based Insecticide Programs for Striped Cucumber Beetle (Coleoptera: Chrysomelidae) Management in Watermelon

In cucurbit crops such as watermelon, implementation of integrated pest management (IPM) is important due to the high reliance on bees for fruit set, along with mounting evidence of the risks of insecticide use associated with pollinator health. Yet, IPM adoption, on-farm pesticide use behaviors, their costs, and impacts on the primary insect pest (striped cucumber beetle, Acalymma vittatum F.) are poorly known in one of the key watermelon-growing regions, the Midwestern United States. To better understand how to implement IPM into watermelon production, we assessed pest management practices on commercial watermelon farms using 30 field sites in Indiana and Illinois over 2 yr in 2017 and 2018. Across all sampling dates, beetles never crossed the economic threshold of five beetles/plant at any farm and most were maintained at densities far below this level (i.e., <1 beetle/plant). Moreover, we documented a wide range of insecticide inputs (mean ca. 5 applications per field per season; max. 10 applications) that were largely dominated by inexpensive foliar pyrethroid sprays; however, insecticide application frequency was poorly correlated with pest counts, suggesting that most of these applications were unnecessary. We calculated that the cost of the average insecticide program far exceeds the cost of scouting, and thus IPM is estimated to save growers ca. $1,000 per field under average conditions (i.e., field size, insecticide cost). These data strongly indicate that current management practices on commercial farms in the Midwest would benefit from implementing more threshold-based IPM programs with potential increases in both farm profitability and pollination services.

Analysis of long-term outcomes for combined pars plana vitrectomy (PPV) and glaucoma tube shunt surgery in eyes with advanced glaucoma

PURPOSE

To analyze 12- and 24-month visual acuity, intraocular pressure, and complications associated with combined pars plana vitrectomy (PPV) and glaucoma tube shunt placement in eyes with glaucoma.

PATIENTS AND METHODS

A retrospective chart review was performed of patients with advanced glaucoma who underwent combined PPV and tube shunt surgery from 2006 to 2010. A minimum of 12 months of follow-up was required for their inclusion in the study. Visual acuity, intraocular pressure, complications, and number of glaucoma medications at 1 and 2 years postoperatively were analyzed.

RESULTS

Twenty-eight eyes met the inclusion and exclusion criteria. Baseline visual acuity was 20/200 or worse in 14/28 eyes (50.0%) and 20/40 or better in 2/28 eyes (7.1%). Visual acuity remained 20/200 or worse in 50.0% (P=0.921) and 44.4% (P=0.973) of eyes after 1 and 2 years postoperatively, respectively. At baseline, the mean intraocular pressure was 30.4 mm Hg. There was significant improvement in mean IOP at 1 year (14.7 mm Hg, P=0.001) and at 2 years (15.2 mm Hg, P=0.001) postoperatively. Baseline number of glaucoma medications averaged 3.0±1.09 (SD), and improved to 1.8±1.28 (SD) at 1 year (P=0.0002) and to 1.4±1.33 at 2 years (P<0.0001) postoperatively.

CONCLUSION

In this retrospective interventional case series, surgical management of advanced glaucoma with a combination of PPV and glaucoma tube shunt resulted in significantly reduced IOP and glaucoma medications at 1 and 2 years postoperatively.

Distribution and dynamics of Japanese beetles along the Indianapolis Airport perimeter and the influence of land use on trap catch

As part of a program to minimize the accidental transportation of Japanese beetles (Popillia japonica) through cargo aircraft to areas where they are not established, a 4-yr trapping project was initiated to study the relative distribution and dynamics of the beetles along a trap line around the Indianapolis International Airport. Land use influence on beetle abundance (trap catch) was assessed using a geographic information system. Trap catch was consistently high in some locations and low in others. In general, high trap catches occurred near agronomic land planted with corn or soybeans, which are both preferred hosts of adult beetles. Low trap catches generally occurred in areas lacking preferred host plants. The amount of agronomic land within 500 m of the traps was always positively correlated with trap catch. Average trap catches were highly correlated by location from year to year, indicating stability of the relative distribution of the beetles along the trap line. Because high trap catches consistently occurred in the same locations, it can be inferred that trapping can be an effective method to monitor Japanese beetle populations. Taking airport-owned agronomic land out of corn and soybean production near the cargo terminals may reduce beetle activity in these areas.

Progressive outer retinal necrosis syndrome in a lymphoma patient with good visual outcome

PURPOSE

To report an HIV-negative lymphoma patient who developed progressive outer retinal necrosis syndrome and who had a good visual outcome after treatment with two-drug antiviral therapy and intravenous immunoglobulin.

METHODS

Case report.

RESULTS

A 43-year-old man with small lymphocytic lymphoma was diagnosed with progressive outer retinal necrosis in his left eye. Treatment was initiated with intravenous foscarnet and ganciclovir as well as intravenous gammaglobulin at a dose of 0.5 gm/kg per day for 5 days. On the second hospital day he was started on decadron 4 mg orally four times daily. No further posterior retinitis progression was observed despite severe immunosuppression. Visual acuity remained stable at 20/30 with 10 months' follow-up.

CONCLUSIONS

The benefit of using gammaglobulin in progressive outer retinal necrosis is unknown. Given the rapid improvement seen in this patient's retinitis, it may be reasonable to consider the use of gammaglobulin in other cases of infectious retinitis in immunocompromised patients.

Indocyanine green-assisted peeling of the retinal internal limiting membrane during vitrectomy surgery for macular hole repair

OBJECTIVE

To determine the efficacy and safety of indocyanine green (ICG)-assisted retinal internal limiting membrane (ILM) peeling during macular hole repair.

DESIGN

Interventional, noncomparative, prospective case series.

PARTICIPANTS

Twenty-four consecutive patients (24 eyes) with stage 3 or 4 macular holes.

INTERVENTION

All eyes underwent a pars plana vitrectomy, including peeling of the posterior cortical hyaloid when necessary. Indocyanine green dye (0.5%) was instilled into the posterior vitreous cavity over the macula and left in place for 3 to 5 minutes. After removal of the ICG, the retinal ILM was peeled. Medium- to long-acting gas tamponade was used in all cases, and all patients were asked to position face down for 1 to 2 weeks.

MAIN OUTCOME MEASURES

Intraoperative staining properties of ICG, technical ease of peeling of the retinal ILM, postoperative anatomic results, visual acuity, and complications were recorded.

RESULTS

Indocyanine green stained the retinal ILM, but did not stain the underlying retina. Indocyanine green staining greatly facilitated the surgeons' ability to visualize and peel the ILM in each case. Peeled tissue was sent for both light and electron microscopic studies, which confirmed that the ICG-stained tissue was truly retinal ILM. Patients were observed after surgery for an average of 123 days (range, 23-195 days). Anatomic closure of the macular hole was achieved in 21 eyes (88%) with a single surgery. Visual acuity improved in 23 of 24 patients (96%) after surgery. There were no intra- or postoperative complications related to ICG use, and there was no clinical or fluorescein angiographic evidence of ICG toxicity.

CONCLUSIONS

Indocyanine green stains the retinal ILM. This property facilitates ILM peeling by providing a stark contrast between the stained ILM and the unstained retina. Indocyanine green staining of the ILM appears to be a safe and useful adjunct in vitreous surgery for macular hole repair.

Indocyanine green-assisted peeling of the retinal internal limiting membrane

OBJECTIVE

To determine whether indocyanine green (ICG) stains and facilitates peeling of the retinal internal limiting membrane (ILM). To investigate the different staining properties of the posterior cortical hyaloid, retinal ILM, and the retina after ILM removal.

DESIGN

Autopsy eye study.

MATERIALS

Eleven human cadaveric eyes.

METHODS

Open sky vitrectomy including removal of the posterior cortical vitreous was performed. A 0.5% ICG solution was then injected into the posterior vitreous cavity over the macula. The dye was allowed to settle on the macula for 5 minutes and was then removed by mechanical aspiration. Peeling of the ILM was initiated with a bent needle and completed with intraocular forceps. Specimens were submitted for light and electron microscopy.

MAIN OUTCOME MEASURES

Staining properties and ease of peeling of retinal ILM were evaluated. Retinal ILM removal was confirmed by histopathologic and electron microscopic examination.

RESULTS

ICG contact with the retinal surface resulted in bright green staining of the ILM. This stain greatly facilitated ILM peeling by improving direct visualization of the membrane. The underlying retina did not stain, thus providing a clear distinction between the stained ILM and the unstained retina. Continuous circular peeling of the ILM was easily completed with this technique. Light microscopic and ultrastructural studies confirmed removal of the ILM.

CONCLUSIONS

ICG solution distinctly stains the nearly invisible retinal ILM in human cadaveric eyes. ICG staining greatly facilitates ILM peeling by providing a stark contrast between the stained ILM and the unstained retina.

Echographic features of medulloepithelioma

PURPOSE

To evaluate the echographic features of medulloepithelioma that may assist in establishing the diagnosis.

METHODS

Retrospective review identified four eyes with medulloepithelioma studied with echography. Clinical records, echographic findings, histopathologic tumor features, and the clinical course were reviewed.

RESULTS

The initial preoperative diagnosis of medulloepithelioma was uncertain, based on clinical findings alone in three cases but was accurate when echographic findings were combined with clinical findings in all four cases. Cysts posterior to the iris were detected on clinical examination in only two cases, but were revealed on echography in all four cases. Additional echographic findings included irregular high internal reflectivity (n = 4), irregular tumor surface (n = 3), molding around intraocular structures (n = 3), and internal vascularity (n = 2).

CONCLUSIONS

The diagnosis of medulloepithelioma is not always apparent on clinical examination alone. Echographic findings of a highly reflective, irregularly structured tumor with associated cystic changes involving the ciliary body region may help establish a presumed diagnosis of medulloepithelioma.

Management of glaucoma implants occluded by vitreous incarceration

PURPOSE

To review the authors' experience in the management of aphakic or pseudophakic patients without an intact posterior capsule who had undergone glaucoma implant surgery complicated by vitreous incarceration in the tube, resulting in increased intraocular pressure or combined rhegmatogenous and tractional retinal detachment.

METHODS

Retrospective review of the clinical features, treatment, and outcomes of eight patients who had vitreous incarceration in a glaucoma implant drainage tube. In each patient, a model 425 (7 patients) or model 350 (1 patient) Baerveldt glaucoma implant was used.

RESULTS

Vitreous incarceration in the tube was first diagnosed 1 day to 49 weeks after surgery (mean, 7.5 weeks; median, 1 week). The interval between glaucoma implant surgery and pars plana vitrectomy ranged from 22 to 365 days (mean, 125 days). Before management with pars plana vitrectomy or neodymium:yttrium-aluminum-garnet laser vitreolysis, intraocular pressure ranged from 25 to 62 mm Hg (mean, 40 mm Hg). Four patients were initially treated with neodymium:yttrium-aluminum-garnet laser vitreolysis, which was successful in only one patient. Six patients were successfully treated with pars plana vitrectomy, and one patient declined surgery. Follow-up after treatment of the incarceration ranged from 5 weeks to 15 months (mean, 8.3 months). After pars plana vitrectomy, intraocular pressure ranged from 9 to 24 mm Hg (average, 14 mm Hg). Postoperative visual acuity remained within one line of the preoperative visual acuity in each of the six patients undergoing pars plana vitrectomy.

CONCLUSIONS

Pars plana vitrectomy is effective in managing vitreous incarceration in glaucoma implant tubes. Previous anterior vitrectomy does not prevent incarceration.

Effect of insecticides on the diamondback moth (Lepidoptera: Plutellidae) and its parasitoid Diadegma insulare (Hymenoptera: Ichneumonidae)

Studies were conducted to evaluate the toxicity of insecticides to adult Diadegma insulare (Cresson) and its host the diamondback moth, Plutella xylostella (L.). Leaf-dip and direct-dip bioassays for diamondback moth larvae and residual bioassays for adults of diamondback moth and D. insulare were used to assess mortalities. Larval mortalities at field rates were significantly higher with carbaryl, permethrin, spinosad, and tebufenozide when compared with Bacillus thuringiensis, or imidacloprid in the larval-dip bioassay 72 h after treatment. In the leaf-dip and residual bioassays, both permethrin and spinosad caused 100% mortalities to diamondback moth larvae and adults, respectively, 72 h after treatment. Of all the materials tested, only B. thuringiensis and tebufenozide were not toxic to D. insulare 24 h after treatment. Spinosad was not toxic to D. insulare 30 min after treatment. However, 100% mortality was observed 8 h after treatment.

Development of a multiple-drug delivery implant for intraocular management of proliferative vitreoretinopathy

A prototype multiple-drug delivery implant has been developed for the intraocular management of proliferative vitreoretinopathy (PVR). Because of the recurrent nature of the disease, PVR causes blindness in approximately 7% of patients who have undergone retinal re-attachment surgery. The poly(dl-lactide-co-glycolide) 50/50 (PLGA) implant consists of three cylindrical segments, each of which contains one of the following drugs: 5-fluorouridine (5FUrd, an antimetabolite), triamcinolone (Triam, a corticosteroid), and human recombinant tissue plasminogen activator (t-PA, a thrombolytic agent). The device can be inserted through a 20-gauge syringe needle into the vitreous body of the eye. The implant also possesses a PLGA coating over the t-PA-containing terminal segment, which creates a lag-time to deliver t-PA when most needed and to decrease the risk of postoperative bleeding. Two methods of cylinder fabrication were investigated: heat and solvent extrusion. The release behavior of several drugs was examined as a function of the processing variables including: extrusion method, drug loading, polymer molecular weight, and drug particle size. The presence of either the organic solvent (acetone) during processing or a highly water-soluble drug (5FUrd) in the formulation increased the polymer porosity, which in turn, increased the drug release-rate. Drug loading effects were consistent with percolation concepts, and a low-molecular-weight PLGA (e.g., Mw=42000 for inherent viscosity=0.58 dl/g) was desirable to produce controlled release close to one month. Based on pharmacological and pharmacokinetic data of these compounds and our clinical experience with this disease, several design criteria for a combined implant were devised. Optimal cylindrical segments from the formulation studies were selected and combined in series to form a contiguous implant. After successful combination and coating procedures were developed, prototype implants were prepared. From the 3-drug prototype, 5FUrd and Triam were released approximately 1 microgram/day for over 4 weeks and 10-190 microgram/day over 2 weeks, respectively. The solvent-extrusion procedure did not significantly alter the stability of the encapsulated t-PA (>94+/-5% serine protease activity after preparation). After a lag-time of approximately 2 days, t-PA was released active at a rate of approximately 0.2-0.5 microgram/day in approximately 2 weeks. The release characteristics from the combined implant largely met our initial design criteria. Hence, controlled-release implants of this kind may have potential use for intraocular treatment of PVR.

Long-term follow-up of extracapsular cataract extraction and posterior chamber intraocular lens implantation in patients with uveitis

OBJECTIVE

The objective of the study was to determine the long-term outcome of patients with uveitis who underwent extracapsular cataract extraction (ECCE) and posterior chamber intraocular lens (PCIOL) implantation.

DESIGN

Retrospective review.

PARTICIPANTS

Twenty-eight patients (36 eyes).

INTERVENTION

Extracapsular cataract extraction and PCIOL implantation.

MAIN OUTCOME MEASURES

Level of best-corrected Snellen visual acuity, change in visual acuity, length of follow-up, long-term findings, and complications.

RESULTS

In long-term follow-up (mean, 81.4 months), 94% of eyes had visual acuity improvement compared with preoperative levels. Average change in visual acuity for all eyes was an improvement of 6.4 Snellen lines; 75% of eyes were 20/40 or better. The prevalences of cystoid macular edema (CME), epiretinal membrane (ERM), and posterior capsule opacification (PCO) were 56%, 56%, and 58%, respectively.

CONCLUSIONS

Patients with uveitis who are treated with ECCE with PCIOL implantation can have successful visual results in long-term follow-up despite the prevalence of PCO or macular abnormalities such as CME and ERM.

Changes in left ventricular mass and volumes in patients receiving angiotensin-converting enzyme inhibitor therapy for left ventricular dysfunction after Q-wave myocardial infarction

OBJECTIVES

We evaluated global and segmental left ventricular (LV) mass and LV mass/volume ratio in patients with LV dysfunction receiving angiotensin-converting enzyme (ACE) inhibitor therapy after acute myocardial infarction (MI).

BACKGROUND

ACE inhibitors attenuate LV dilatation and compensatory hypertrophy after acute MI in animal models. However, LV remodeling in patients after acute MI has been largely defined on the basis of changes in chamber volume alone.

METHODS AND RESULTS

Twenty-nine patients with LV ejection fraction <40% received the ACE inhibitor ramipril (range 2.5 to 20 mg/day) within 5 days of their first Q-wave MI. Magnetic resonance imaging was performed at baseline and at 3 months, providing global and regional LV volumes and mass from summated serial short-axis slices. Mean arterial blood pressure was unchanged from baseline to 3-month follow-up (89 +/- 10 to 92 +/- 17 mm Hg). LV mass decreased (90 +/- 25 to 77 +/- 21 gm/m2, p < 0.0005) as LV end-diastolic volumes increased (65 +/- 13 to 73 +/- 22 ml/m2, p < 0.01). Global LV mass to volume ratio decreased from 1.40 +/- 0.28 to 1.08 +/- 0.18 gm/ml (p < 0.0001), as did circumferential wall thickness to volume ratio of noninfarcted myocardium at the base of the LV (0.06 +/- 0.02 to 0.05 +/- 0.02 mm/ml, p < 0.001). LV ejection fraction increased from 35 +/- 6 to 40 +/- 9% (p < 0.001) in the presence of an increase in calculated end-systolic wall stress (185 +/- 57 to 227 +/- 54 gm/cm2, p < 0.01).

CONCLUSIONS

ACE inhibitor therapy was associated with improved LV function in the face of a decrease in mass to volume ratio of the LV as well as a decrease in wall thickness to volume ratio of noninfarcted myocardium. Whether ACE inhibitor therapy had direct or indirect effects on these changes in LV mass and function are open questions that require further investigation.

Evaluation of hibernating myocardium in patients with ischemic heart disease

Patients with ischemic heart disease and significant left ventricular dysfunction are often difficult to manage medically. Revascularization procedures may improve left ventricular function and prognosis in this population if hypocontractile yet viable myocardium (hibernating myocardium) is demonstrated. Nuclear cardiology studies (single photon and positron methods), two-dimensional echocardiography, and magnetic resonance imaging studies have been utilized to identify hibernating myocardium. If thallium-201 studies are performed, the use of reinjection of thallium and repeat imaging improves the sensitivity of these studies for the detection of viable myocardium. Dobutamine echocardiographic studies may have a higher specificity and positive predictive value for the subsequent improvement of regional systolic left ventricular function after revascularization than the nuclear techniques. However, thallium studies have an excellent negative predictive value. Positron emission tomography (PET) allows the simultaneous assessment of perfusion and metabolic activity; however, these studies are expensive and not widely available. Functional evaluation with PET is in its infancy. Functional cardiac magnetic resonance imaging (MRI), although not widely available yet, provides the most accurate evaluation of regional ventricular function. MRI spectroscopy may be utilized to assess myocardial viability. As acquisition times improve and "real-time" imaging becomes a reality, MRI and MRI spectroscopy will likely become very accurate tools for assessing functional reserve and metabolic activity. The selection of the most appropriate method for assessment of myocardial viability will include consideration of a patient's characteristics, the presence of coronary arterial tree amenable to revascularization techniques, the techniques available to the clinician to assess viability, and local revascularization experience in this population. The result of an individual patient's evaluation is relevant to the consideration of coronary revascularization, or if this is not possible, cardiac transplantation.

Leukocoria caused by occult penetrating trauma in a child

PURPOSE

To report a child with leukocoria caused by occult penetrating trauma.

METHODS

Case report. The clinical findings and surgical repair of acquired leukocoria of the right eye in a 2-year-old boy are presented.

RESULTS

In the right eye, slit-lamp examination disclosed a retrolenticular cyclitic membrane and moderately severe (3+) cells and flare anterior chamber reaction. The eye was hypotonous, and B scan showed that the membrane was associated with a retinal detachment. Surgery was performed to repair the retinal detachment and to remove the retrolenticular membrane. Two months before initial examination, the patient had been attacked by a rooster.

CONCLUSION

Occult penetrating trauma should be considered in the differential diagnosis of pediatric leukocoria.

Common k-space acquisition: a method to improve myocardial grid-tag contrast

A current limitation of many myocardial tag acquisitions employing SPAMM encoding is the relatively rapid loss of tag contrast over the cardiac cycle. Acquisition schemes that apply line tags produce prolonged tag contrast compared with directly excited grid tags. However, a grid-tag series can be generated by combining two orthogonal line-tag series. To be time efficient, each line-tag series can be acquired with the read gradient oriented perpendicular to the line-tag direction. There are several disadvantages associated with this approach, including the requirement to avoid signal fold-over and that fat shift artifacts appear in different directions in each line-tag series. Presented here is a method of applying separate line tags that does not require interchanging the read and phase encoding gradients and does not extend the scan time compared with a conventional grid-tag acquisition. Additionally, the means of generating grid tags results in a doubling of the tag contrast to noise ratio compared a line-tag set. Computer simulations are presented along with phantom and volunteer scans.

Rapid cardiac imaging with turbo BRISK

A variety of variable and constant rate, sparse sampling strategies have previously been proposed to rapidly image dynamically changing objects. The majority of these strategies compile a k-space data set for any given time point by substituting k-space data from the most recently sampled time positions (extracted from the sparsely sampled set). The BRISK technique, is a variable rate, sparse sampling technique which additionally incorporates an interpolation scheme to more accurately represent k-space data at positions which were not directly sampled. Here, strategies are introduced that allow tubo concepts to be incorporated with BRISK. Simulations are conducted to compare the efficacy of the turbo BRISK acquisition and processing strategy against a constant rate, sparse sampling strategy with direct substitution of the most recently acquired k-space lines. It is shown that turbo BRISK generates images of similar quality in approximately half the time as the uniform sampling rate, sparse sampling strategy. Data from turbo BRISK acquisitions of multicardiac phase image sets, obtained on a normal volunteer and cardiac patients are presented.

Angiotensin-converting enzyme inhibitor therapy affects left ventricular mass in patients with ejection fraction > 40% after acute myocardial infarction

OBJECTIVES

We tested the hypothesis that angiotensin-converting enzyme (ACE) inhibitor therapy decreases left ventricular (LV) mass in patients with a left ventricular ejection fraction (LVEF) > 40% and no evidence of heart failure after their first acute Q wave myocardial infarction (MI).

BACKGROUND

Recently, ACE inhibitor therapy has been shown to have an early mortality benefit in unselected patients with acute MI, including patients without heart failure and a LVEF > 35%. However, the effects on LV mass and volume in this patient population have not been studied.

METHODS

Thirty-five patients with a LVEF > 40% after their first acute Q wave MI were randomized to titrated oral ramipril (n = 20) or conventional therapy (control, n = 15). Magnetic resonance imaging (MRI) performed an average of 7 days and 3 months after MI provided LV volumes and mass from summated serial short-axis slices.

RESULTS

Left ventricular end-diastolic volume index did not change in ramipril-treated patients (62 +/- 16 [SD] to 66 +/- 17 ml/m2) or in control patients (62 +/- 16 to 68 +/- 17 ml/m2), and stroke volume index increased significantly in both groups. However, LV mass index decreased in ramipril-treated patients (82 +/- 18 to 73 +/- 19 g/m2, p = 0.0002) but not in the control patients (77 +/- 15 to 79 +/- 23 g/m2). Systolic arterial pressure did not change in either group at 3-month follow-up.

CONCLUSIONS

In patients with a LVEF > 40% after acute MI, ramipril decreased LV mass, and blood pressure and LV function were unchanged after 3 months of therapy. Whether the decrease in mass represents a sustained effect that is associated with a decrease in morbid events requires further investigation.

Acute posterior multifocal placoid pigment epitheliopathy after acute group A streptococcal infection

PURPOSE

We studied a case of acute posterior multifocal placoid pigment epitheliopathy in a 40-year-old man who had had an acute febrile illness.

METHODS

The medical record was reviewed for clinical manifestations, course of disease, and laboratory findings, including results of fluorescein and indocyanine green angiography.

RESULTS

The patient had the typical clinical course of acute posterior multifocal placoid pigment epitheliopathy with spontaneous resolution of posterior pole lesions and improvement in visual acuity from 20/60 to 20/20. The laboratory evaluation was remarkable for a rise in the anti-DNAse B antibody titer between initial and convalescent-phase serum samples, providing evidence of recent group A streptococcal infection.

CONCLUSION

Although acute posterior multifocal placoid pigment epitheliopathy is often attributed to a postviral condition, this syndrome may also develop after an acute group A streptococcal infection.

Treatment of clinically resistant cytomegalovirus retinitis with combined intravitreal injections of ganciclovir and foscarnet

PURPOSE

To determine the efficacy of combined ganciclovir and foscarnet intravitreal injections in controlling clinically resistant cytomegalovirus retinitis in a 37-year-old man with the acquired immunodeficiency syndrome who refused systemic therapy.

METHODS

The patient refused systemic therapy and was treated with intravitreal injections of ganciclovir and foscarnet, which were then combined when the retinitis became resistant to either drug alone.

RESULTS

The retinitis was initially controlled with bilateral intravitreal ganciclovir injections. After reactivation of retinitis in the left eye, intravitreal foscarnet was effective until recurrent retinitis threatened the center of the fovea. The retinitis continued to progress until combined intravitreal injections of ganciclovir and foscarnet were administered.

CONCLUSIONS

Combined intravitreal injections of ganciclovir and foscarnet may be effective in treating cytomegalovirus retinitis when the infection is clinically resistant to either intravitreal drug alone. Intravitreal injections can be effective in controlling cytomegalovirus retinitis in patients who are intolerant of or refuse systemic therapy.

Bacterial contamination of anaerobic vitreous cultures: using techniques employed for endophthalmitis

PURPOSE

To investigate the occurrence of contaminated cultures of vitreous specimens from non-infected eyes obtained using anaerobic techniques employed for endophthalmitis.

METHODS

Vitreous specimens were obtained using meticulous sterile techniques employed for endophthalmitis from seventeen patients undergoing pars plana vitrectomy for non-infective indications: vitreous hemorrhage (12 eyes), retinal detachment (3), Coat's disease (1), and congenital dislocated lens(1). Vitreous specimens were inoculated in the operating room onto an anaerobic blood agar plate and into thioglycolate broth. Bacterial growth occurring before 10 days was considered positive.

RESULTS

Three organisms were isolated from three separate eyes. One colony of Staphylococcus species was isolated on an anaerobic blood agar plate on day 3. A single colony of Propionibacterium acnes grew on an anaerobic blood agar plate on day 6. Alpha-hemolytic streptococci grew from thioglycolate broth on day 10.

CONCLUSIONS

Growth as detected in this study might represent contaminating rather than an infecting organism in an eye suspected of having endophthalmitis.

Useful visual outcomes after treatment of Bacillus cereus endophthalmitis

PURPOSE

Bacillus cereus endophthalmitis occurring after penetrating ocular trauma has been almost always associated with a poor visual outcome. The purpose of our study was to review and report patients who had useful visual acuity outcomes.

METHODS

The study group consisted of five patients from a single medical center with penetrating ocular trauma and endophthalmitis caused by B. cereus. The study population was derived from a review of the microbiology records, clinical records, and operative reports of patients with culture-proven, post-traumatic endophthalmitis over a 15-year period. Patients were only included if the final visual acuity outcomes were 20/200 or better.

RESULTS

All five patients had penetrating ocular injuries, and four patients had a retained intraocular foreign body. Endophthalmitis was diagnosed preoperatively in three patients and intraoperatively in two patients. All patients underwent pars plana vitrectomy and injection of intravitreal and periocular antibiotics. Postoperatively, a rhegmatogenous retinal detachment developed in three patients between 4 weeks and 12 months after the injury (average, 19 weeks); all retinal detachments were reattached with additional vitreoretinal surgery. Final postoperative visual acuities were 20/200 (two patients), 20/30 (one patient), and 20/25 (two patients). The postoperative follow-up time interval ranged from 12 months to 30 months (average, 19.2 months).

CONCLUSION

The current series adds further support to the observation that certain eyes with post-traumatic B. cereus endophthalmitis may be associated with preservation of anatomic integrity and restoration of useful visual acuity.

Plasmapheresis treatment of central retinal vein occlusion in a young adult

PURPOSE/METHODS

A 16-year-old girl with mixed connective tissue disease had central retinal vein occlusion. The patient was treated with plasmapheresis.

RESULTS/CONCLUSION

Resolution of clinical findings of central retinal vein occlusion was documented by fluorescein angiography and visual field tests within 15 days of treatment. Plasmapheresis may be effective therapy in carefully selected cases of central retinal vein occlusion in young adults.

An unusual ocular manifestation of discoid lupus erythematosus

BACKGROUND

Discoid lupus erythematosus is a chronic skin disease characterized by well-demarcated papules and plaques. Mucous membrane changes are common; however, conjunctival involvement is unusual. We report a case of unilateral, chronic, isolated discoid lupus erythematosus of the conjunctiva.

OBSERVATIONS

A 32-year-old man presented for evaluation of chronic conjunctivitis of the right eye that had persisted for 9 years. A biopsy of the bulbar conjunctiva revealed a mixed mononuclear cellular infiltrate distributed along the epithelial basement membrane zone and around the stromal blood vessels. Immunohistopathologic examination revealed a diffuse, granular pattern of fluorescence corresponding to immunoglobulins and complement components along the epithelial basement membrane zone and in the walls of the stromal blood vessels. Electron microscopy demonstrated changes in the epithelial basal lamina consistent with discoid lupus erythematosus, including areas that were multilayered. Immunoelectron microscopy identified sub-basal lamina deposits of immunoglobulin G.

CONCLUSIONS

Discoid lupus erythematosus should be a suspected cause of chronic conjunctival inflammation; the diagnosis is substantiated by immunopathologic and ultrastructural studies.

Concurrent endophthalmitis and retinal detachment

PURPOSE

Eyes with concurrent endophthalmitis and retinal detachment usually have a poor anatomic and visual outcome after treatment. The purpose of this study is to define the relation among the causative organism, the results of retinal detachment repair, and the final visual acuity.

METHODS

Data were retrieved by a retrospective, computer-assisted review of the coded inpatient diagnoses from April 1987 through March 1992.

RESULTS

This study included 16 patients (9 males, 7 females) ranging in age from 5 to 88 years (average, 58.7 years). Endophthalmitis was classified as exogenous in 13 (81%) patients and endogenous in 3 (19%). Two groups were identified: a virulent group that included eight (50%) patients (Staphylococcus aureus, streptococci, gram-negative, Bacillus), and a less-virulent group that included eight (50%) patients (Staphylococcus epidermidis, Propionibacterium acnes, fungal). The initial surgical procedure consisted of diagnostic vitreous fluid collection by pars plana vitrectomy (11 cases), anterior vitrectomy (1 case), or vitreous aspiration (4 cases). Additional initial adjunctive surgical procedures included pars plana lensectomy (2 cases), scleral buckling (6 cases), fluid-gas exchange (7 cases), and intraocular antibiotic injections (9 cases). In six (75%) of eight patients with endophthalmitis in the virulent group, the retina remained detached. However, in seven (88%) of eight patients with endophthalmitis in the less-virulent group, the retina remained reattached postoperatively, and the remaining patient had a stable, nonprogressive peripheral tractional retinal detachment. None of the eight patients with endophthalmitis in the virulent group retained a postoperative visual acuity of better than 3/200, and four (50%) lost all light perception. Five (62%) of the eight patients with endophthalmitis in the less-virulent group retained a postoperative visual acuity of 5/200 or better, and none lost all light perception.

CONCLUSIONS

Concurrent endophthalmitis and retinal detachment patients with virulent organisms have a poor prognosis. Visual and anatomic outcomes were better in the less-virulent group.

Combined extracapsular cataract extraction, posterior chamber intraocular lens implantation, and pars plana vitrectomy

The surgical management of coexisting cataract and vitreoretinal disease has been controversial, particularly for eyes with a history of proliferative diabetic retinopathy (PDR) or chronic uveitis. We retrospectively studied the results of combined extracapsular cataract extraction (ECCE), posterior chamber intraocular lens (PC-IOL) implantation, and pars plana vitrectomy in 20 eyes of 16 patients. The indications for combined vitrectomy included dense, nonclearing vitreous hemorrhage attributed to PDR in 10 eyes, age-related macular degeneration in 2, and trauma in 1. The remaining 7 eyes had pars plana vitrectomy to remove inflammatory vitreous cell and debris associated with chronic uveitis. Follow up ranged from 4 to 32 months (average, 17.4 months). Visual acuity improved in 19 eyes (95%)--to 20/100 or better in 12 (60%). The improvement ranged from 1 to 13 Snellen lines (average, 4.9 lines). Postoperative visual acuity improvement averaged 7.5 Snellen lines for eyes with chronic uveitis, 7.0 lines for those with age-related macular degeneration, and 3.3 lines for those with a history of PDR. Postoperative visual acuity was less than 20/100 in 8 eyes (40%). In most cases, these latter results were attributed to macular changes associated with the underlying ocular disease. Our results confirm previous studies that have shown that combined ECCE/PC-IOL implantation and pars plana vitrectomy is a well-tolerated surgical procedure for diabetics, which can provide clear anterior and posterior segment media. In addition, our results suggest that this combined procedure can be useful in restoring vision in certain eyes with uveitis in the short-term postoperative period.

Extracapsular cataract extraction and posterior chamber intraocular lens implantation in uveitis patients

PURPOSE

Intraocular lens implantation in uveitis patients has been a controversial issue. The purpose of this study is to evaluate the visual and surgical outcomes of extracapsular cataract extraction (ECCE) and posterior chamber intraocular lens (PC IOL) implantation in a diverse group of uveitis patients.

PATIENTS AND METHODS

The results of 39 cases of ECCE and PC IOL implantation in 30 patients with uveitis were retrospectively analyzed. Five patients (six eyes) had pars plana vitrectomies combined with ECCE and PC IOL implantation. Patient age ranged from 26 to 71 years (average, 53.0 years). Specific uveitic syndromes were determined for 22 patients (73.3%). The postoperative follow-up period ranged from 6 to 43 months (average, 20.3 months).

RESULTS

Visual acuity improved postoperatively in 38 eyes (97.4%), and this improvement ranged from 1 to 11 Snellen lines (average, 7.5 Snellen lines). Visual acuity improved postoperatively to 20/40 or better in 32 eyes (82%). Seven eyes had visual acuity worse than 20/40, which was attributed to posterior segment abnormalities after ECCE and PC IOL implantation. Uveitis recurred in 20 eyes (51.3%), and postoperative cystoid macular edema (CME) was observed in 18 eyes (46.2%). In all cases, the recurrent uveitis and CME improved or resolved with corticosteroid therapy.

CONCLUSION

These results suggest selected uveitis patients can have improved vision without unacceptable risk for 1 to 3 years after ECCE and PC IOL implantation.

Effects of subacute pyridostigmine administration on mammalian skeletal muscle function

The subacute effects of pyridostigmine bromide were investigated on the contractile properties of rat extensor digitorum longus (EDL) and diaphragm muscles. The cholinesterase inhibitor was delivered via subcutaneously implanted osmotic minipumps (Alzet) at 9 micrograms h-1 (low dose) or 60 micrograms h-1 (high dose). Animals receiving high-dose pyridostigmine pumps exhibited marked alterations in muscle properties within the first day of exposure that persisted for the remaining 13 days. With 0.1 Hz stimulation, EDL twitch tensions of treated animals were elevated relative to control. Repetitive stimulation at frequencies greater than 1 Hz led a use-dependent depression in the amplitude of successive twitches during the train. Recovery from pyridostigmine was essentially complete by 1 day of withdrawal. Rats implanted with low-dose pyridostigmine pumps showed little or no alteration of in vivo twitch tensions during the entire 14 days of treatment. Diaphragm and EDL muscles excised from pyridostigmine-treated rats and tested in vitro showed no significant alterations in twitch and tetanic tensions and displayed the same sensitivity as muscles of control animals to subsequent pyridostigmine exposures. In the presence of atropine, subacutely administered pyridostigmine protected rats from two LD50 doses of the irreversible cholinesterase inhibitor, soman. In the absence of atropine, the LD50 of soman was not altered by subacute pyridostigmine treatment.

Presumed Pneumocystis carinii choroiditis. Unifocal presentation, regression with intravenous pentamidine, and choroiditis recurrence

Pneumocystis carinii choroiditis is a well-documented but rare infection that has been described as a bilateral, multifocal process. Treatment efficacy has not been well established. In this report, three cases of presumed P. carinii choroiditis that developed during aerosolized pentamidine therapy for the prophylaxis of P. carinii pneumonia are described. All patients had unilateral choroiditis, and two patients were first observed to have unifocal choroiditis. In all patients, choroidal lesions decreased in size with intravenous pentamidine treatment. Choroiditis exacerbated in the two unifocal cases after the frequency of maintenance intravenous pentamidine therapy was decreased. P. carinii choroiditis may appear as a unifocal, unilateral lesion that may represent an earlier stage of infection than previously described. Intravenous pentamidine therapy appears to control P. carinii choroiditis but may need to be continued to prevent exacerbation. Patients receiving prophylactic aerosolized pentamidine therapy are not protected against extrapulmonary disease, and presumed P. carinii choroiditis may serve as a marker for disseminated infection.

Acute multifocal inner retinitis

Two patients developed acute changes in vision two to four weeks after a febrile illness. On ophthalmic examination, each patient had bilateral vitreitis without anterior segment inflammation and multiple, bilateral, round, yellow-white inner retinal lesions that were located in the posterior pole and midperiphery. Laboratory tests did not contribute to a diagnosis. Symptomatic visual loss was caused by neuroretinitis and serous retinal detachment in one patient and by an occluded branch retinal artery in the other. The multifocal retinal lesions resolved gradually without treatment over several months with minimal or no residual retinal changes. Acute multifocal inner retinal lesions may be associated with a preceding nonspecific viral illness and may cause a sudden change in vision if associated with neuroretinitis, serous retinal detachment, or retinal vessel occlusion. We have termed this constellation of ophthalmic findings acute multifocal inner retinitis.

Respiratory and cardiovascular effects of tetrodotoxin in urethane-anesthetized guinea pigs

Cardiorespiratory effects of tetrodotoxin (TTX) (15 micrograms/kg, i.p.) were investigated in urethane-anesthetized guinea pigs acutely instrumented for the recording of medullary respiratory-related units (RRUs), diaphragm electromyogram (DEMG), electrocorticogram (ECoG), electrocardiogram (ECG), blood pressure (BP), endtidal CO2, and arterial O2 and CO2. Respiratory system responses showed a hyperventilatory profile during the initial stage of intoxication. This was followed by an abrupt onset of a progressive decrease in the respiratory frequency, and a respiratory rate depression-related respiratory failure. The average time to TTX-induced respiratory arrest and death was 10.3 +/- 4.2 min. Concurrently recorded inspiratory and expiratory RRU activities indicated that respiration invariably failed in an end-expiratory position as manifested by a sustained period of expiratory RRU discharge. The progressive rate depression prior to respiratory arrest was temporally correlated only to a concomitantly augmenting expiratory RRU discharge duration. Inspiratory RRU discharge duration, on the other hand, did not display any significant change throughout the course of intoxication. The asymmetry in RRU response patterns indicates either an expiratory network component's particular sensitivity to perturbation by TTX or a dissociative trend in some bulbar respiratory rhythmogenic mechanisms. Peripheral cardiorespiratory changes were also quite profound. These included a gradual and steadfast decline in BP, a steadily decreasing amplitude in DEMG oscillations, and a state of progressive hypercapnia and hypoxemia. Changes in heart rate and ECG waveform attributes prior to respiratory arrest were not appreciable. In conclusion, in addition to a variety of TTX-induced peripheral cardiorespiratory effects, findings from this study have revealed a central respiratory system component that appears to show an unusual sensitivity to perturbation by TTX. The significance of this unique phenomenon as it relates to the nature and extent of TTX-induced central respiratory depression is discussed.

Neurophysiological concomitants of soman-induced respiratory depression in awake, behaving guinea pigs

Soman-induced respiratory failure was investigated in awake, behaving guinea pigs chronically instrumented to allow concurrent recordings of medullary respiratory-related unit (RRU) activity, diaphragm electromyogram (DEMG), and electrocorticogram. Responses to soman typically began with hyperpnea. Loss of consciousness, as indicated by the development of seizure activities, took place shortly after the onset of hyperpnea. This was followed by dyspnea, hypopnea, and finally, respiratory failure. The most profound respiratory dysfunctions were seen during the development of dyspnea characterized by a progressively degenerative RRU-DEMG phase relationship (phase anomalies) and mixed patterns of ataxic breathing. Electrophysiographic records indicated that the anomalous RRU-DEMG phase phenomenon is attributable to a state of functional dissociation in some brainstem mechanisms that are normally involved in the orchestration of a synchronous respiratory drive. The failure of bulbar rhythmogenic mechanisms to maintain an orderly and synchronous recruitment of respiratory drive, which led to untimely and chaotic activations of respiratory muscles, was apparently the underlying cause of various ataxic breathing patterns and a reduced ventilatory efficiency. Spectral analyses of DEMG activities showed that, despite episodic muscle fasciculations and signs of fatigue, the functional integrity of the diaphragm was not significantly compromised by soman at a dose sufficient to produce respiratory failure. These findings not only support the notion of a relatively more important involvement of central respiratory mechanisms in soman-induced respiratory failure, but also identify a state of functional dissociation of central respiratory timing mechanisms as being a significant component in soman intoxication.

Freeze fracture analysis of the axolemma of cultured dorsal root ganglion neurons in the absence of Schwann cells

The distribution of intramembranous particles within the axolemma of cultured dorsal root ganglion neurons was determined by freeze-fracture microscopy. Utilizing culture conditions which eliminate Schwann cells, the particle distribution of the P-face, 735 +/- 119 microns2, and E-face, 100 +/- 39 microns2 resembled that of pre- and non-myelinated axons in vivo and no node-like E-face particle patching was seen. These results indicate that cultured neurite development is similar to that seen in vivo and that axons maintained in a glial-free environment do not develop nodal, E-face membrane specializations.

HIV screening and counseling for intravenous drug abuse patients. Staff and patient attitudes

At least one third of patients enrolled in a methadone maintenance treatment program are willing to comply voluntarily with screening for and counseling about human immunodeficiency virus (HIV). A questionnaire about knowledge, attitudes, and behavior concerning acquired immunodeficiency syndrome was answered anonymously by 79% (46) of the clinical staff and 67% (868) of the enrolled patients. On their own initiative, 21% of the patients had already received voluntary anonymous HIV screening and brief counseling, seldom discussing the result with the staff. Approximately 90% of the staff and a majority of the patients (72%) thought a voluntary HIV screening program should be offered to all patients. Almost all staff (98%), but only 50% of the patients, felt the HIV test results should be known to physicians, nurses, and counselors at the clinic. Few staff members (15%) believed that patients had changed their sex behavior; more (48%) felt that needle sharing was reduced. Patients believed methadone patients in general had changed their sex behavior (49.2%) and reduced needle sharing (62%) to prevent becoming infected. Patients reported statistically significant reductions both in number of sex partners and in personal needle sharing during the past year.

Age-related responses to influenza vaccination in the Newcastle region during 1983 and 1984

A study was carried out in Newcastle to assess responses to influenza vaccines in elderly nursing home patients and in younger adults during 1983 and 1984. The decision to vaccinate the elderly subjects was made by their general practitioners. A concurrent randomized placebo-controlled trial of the same vaccine was performed in young adult volunteers. Elderly subjects generally possessed higher levels of pre-existing antibody to the influenzal haemagglutinins that were present in the vaccines than did younger subjects. The highest levels were observed in the 52-63 years' age group. Younger subjects showed significantly greater responses to vaccines compared with elderly subjects (P less than 0.05). Peak responses were noted in the 16-24 years' age group. Of a total of 326 elderly subjects (70% of whom had been vaccinated), six participants, two of whom had been vaccinated, contracted laboratory-proven influenza during 1983. Only one unvaccinated subject of a total of 365 subjects (50% of whom had been vaccinated) contracted influenza during 1984. In both years illness was produced by strain A/Philippines/2/82.

Monitoring the bioenergetics of cardiac allograft rejection using in vivo P-31 nuclear magnetic resonance spectroscopy

Monitoring human cardiac allograft rejection is currently accomplished by endomyocardial biopsy. Available noninvasive methods for identifying rejection have lacked the necessary sensitivity or specificity, or both, for routine clinical application. In vivo phosphorus-31 (P-31) nuclear magnetic resonance (NMR) spectroscopy has been used for monitoring phosphorus metabolism in both animal models and humans. In the present study this technique was employed as a noninvasive means to assess the bioenergetic processes that occur during cardiac allograft rejection in a rat model. Brown Norway rat hearts were transplanted subcutaneously into the anterior region of the neck of Lewis rat recipients (allografts). Control isografts employed Lewis donors and recipients. Phosphocreatine to inorganic phosphate (PCr/Pi), phosphocreatine to beta-adenosine triphosphate (PCr/ATP beta), beta-adenosine triphosphate to inorganic phosphate (ATP beta/Pi) ratios and pH of the transplanted hearts were monitored using surface coil P-31 NMR spectroscopy (at 4.7 tesla) daily for 7 days. To allow recovery from the compromise induced by the surgical procedure, the measurements obtained on day 2 were taken as a baseline. PCr/Pi was unchanged or increased in the isografts but decreased continually in allografts, with the difference becoming significant by day 4 when compared with levels in day 2 allografts (p less than 0.005) and by day 3 when compared with levels in the isograft group (p less than 0.05). PCr/ATP beta in isografts did not change throughout the study; however, allografts demonstrated a significant decrease as early as day 3 (p less than 0.01), although a significant difference between isografts and allografts did not become manifest until day 4 (p less than 0.005).(ABSTRACT TRUNCATED AT 250 WORDS)

Oscillatory behavior in inferior olive neurons: mechanism, modulation, cell aggregates

Inferior olive neurons, in brain slices maintained in vitro, display spontaneous, continuous oscillations of their membrane potential which are consonant with olivary rhythmic activity seen in vivo. This oscillatory behavior was studied with intracellular electrophysiological techniques. The 3-10 Hz rhythmicity of these cells from guinea pigs is tetrodotoxin resistant and dependent on a somatic calcium conductance. The oscillatory behavior can exhibit intrinsic frequency modulation and can be altered by synaptic processes. Synaptic alteration of the oscillatory behavior by afferent sources and extensive electrotonic coupling between cells in local aggregates (shown by Lucifer yellow dye-coupling) provide the substrate for a potent central pattern generator with a well established efferent pathway for control of motor functions.

The inferior olivary complex of guinea pig: cytoarchitecture and cellular morphology

The inferior olivary complex (I.O.C.) of the guinea pig can be divided into three primary subdivisions: the principal olive (PO), the medial accessory olive (MAO), and the dorsal accessory olive (DAO). In Nissl-stained preparations, the PO possessed darker staining cells than did the MAO and DAO and was the most densely populated with cells. All neuronal somata in the I.O.C. were oblique-spheroid in profile (mean size: coronal = 18.3 microns, parasagittal = 15.8 microns). Based on Golgi impregnations, it was apparent that inferior olive cells were of two unique radiate-cell types (I and II). Type I neurons had relatively diffuse, sparsely branched dendritic arbors, whereas type II cells had dendrites which were highly branched and massed about the cell body, at times creating complex spirals. Type II cells were further categorized into types IIa and IIb based on geometric variations of the type II dendritic arbors. Indices of branching and tortuosity, together with estimates of dendritic arbor volume, were quite helpful in distinguishing cell types. The cell types were differentially distributed across the subdivisions with type I neurons being encountered in the MAO while type II cells were found in all three subdivisions. Within the neuropil of the I.O.C., three different afferent axonal arbors were identified, as was the presence of dendrites from surrounding reticular formation cells. Neuronal aggregates creating a possible electrical syncytium within the I.O.C. are consistent with the dendroarchitectonics of the cells.