Multimodal imaging in a case of presumed secondary vitreoretinal lymphoma presenting with inner retina and optic nerve head infiltration.

Purpose: To report the findings supported by multimodal imaging in a case of secondary vitreoretinal lymphoma presenting with inner retina and optic nerve head infiltration. Observations: A 64-year-old man with systemic diffuse large B-cell lymphoma presented with reduced visual acuity. Moderate anterior chamber and vitreous cell were present. Fundus exam showed bilateral disc edema and diffuse opaque macular infiltrates with a pseudo cherry-red spot in the left eye. Optical coherence tomography showed inner retinal infiltration and loss of normal architecture. Surgery for tissue biopsy was discussed and declined due to risk. Instead, multimodal imaging and anterior chamber fluid sampling were used as a surrogate for tissue biopsy and helped rule out infectious uveitis and retinal vascular disease. The patient was empirically treated with intravitreal methotrexate with rapid improvement in vision, exam, and quality of life. Conclusions and importance: Multimodal imaging can support a presumed diagnosis of secondary vitreoretinal lymphoma in order to proceed with intravitreal methotrexate treatment, which can result in rapid clinical and visual improvement.

Intermittent and Unilateral Chorioretinal Folds due to Combined Chiari 1 Malformation and Basilar Invagination.

We report the case of a 35-year-old female with combined Chiari 1 malformation and basilar invagination, who presented with intermittent conjunctival chemosis and unilateral chorioretinal folds that were temporally correlated. She denied any flashes, floaters, eye redness, or pain. She also denied nausea or vomiting. Clinical exam and optical coherence tomography imaging revealed conjunctival chemosis and chorioretinal folds in the left eye. Subsequent magnetic resonance imaging of the brain and the orbits were consistent with combined Chiari 1 malformation and basilar invagination. The unilateral and intermittent chorioretinal folds and conjunctival chemosis presentation of combined Chiari 1 malformation and basilar invagination is unusual. To the best of our knowledge, this is the first case to be reported with this unique clinical presentation. It is most important to be aware that unilateral and intermittent chorioretinal folds associated with conjunctival chemosis may be signs of intracranial disease.

Clinical Features and Treatment Outcome of a Concurrent Central Retinal Vein Occlusion and Cilioretinal Artery Occlusion.

We describe the clinical features and treatment outcome of a patient with combined central retinal vein occlusion and cilioretinal artery occlusion. A 52-year-old female presented to our clinic with decreased vision in the right eye for 4 days. Visual acuity and intraocular pressure were count fingers at 2&1/2M and 14 mm Hg in the right and 20/20 and 16 mm Hg in the left eye, respectively. Funduscopic exam and optical coherence tomography (OCT) of the right eye confirmed the diagnosis of concurrent cilioretinal artery occlusion and central retinal vein occlusion with segmental macular pallor in the territory of the cilioretinal artery, corresponding marked inner retina thickening on OCT and signs of vein occlusion. The patient received an intravitreal injection of bevacizumab and at 1-month follow-up, vision improved to 20/30 with corresponding anatomical improvement. It is very important to recognize combined central retinal vein occlusion and cilioretinal artery occlusion as they could be treated with intravitreal injections of anti-vascular endothelial growth factors with favorable treatment outcomes.

Sequential endogenous endophthalmitis, fungal keratitis, bacteremia and vertebral osteomyelitis in a person who injects drugs.

PURPOSE: To describe multiple ocular (and non-ocular) manifestations of disease that can present in a person who injects drugs (PWID). We report a case of a patient consecutively presenting across multiple visits to an ambulatory eye care clinic as the initial point of contact for endogenous endophthalmitis, fungal keratitis, bacteremia, and psoas abscess with vertebral osteomyelitis within a matter of weeks. OBSERVATIONS: A 51-year-old male with past medical history of alcohol use disorder and injection drug use was initially seen in an eye clinic three days after suffering vision loss in the left eye associated with floaters, photophobia, and eye pain. After initial workup and treatment for panuveitis, endogenous endophthalmitis was suspected. A pars plana vitrectomy was performed, and intravitreal medications were given. A pathogen was never isolated from vitreous samples. Two weeks later, the patient presented with complaints of pain, blurry vision, and foreign body sensation in his opposite (right) eye. Examination revealed a corneal ulcer later identified as a Paecliomyces fungal infection. Two weeks after this, he developed fever, chills, and right-sided flank pain radiating to his testicles. Following evaluation by the emergency department and subsequent hospitalization after bacteremia was noted, he was found to have a right-sided psoas abscess with lumbar vertebral osteomyelitis. Fluid was drained, cultured, and grew methicillin-sensitive Staphylococcus aureus (MSSA). At his last visit, his best-corrected visual acuity was 20/20 OS and 20/30 OD despite central corneal scarring. It was only after hospitalization that he affirmed recent injection drug use, despite being queried about it through the course of his infections. CONCLUSIONS AND IMPORTANCE: Injection drug use is an increasingly common concern for all healthcare providers as the opioid crisis in the United States remains widespread. This case highlights multiple potential infectious processes which may impact persons who inject drugs when seen by eye care providers. It also describes difficulties in caring for people who inject drugs who may not provide critical and timely information relating to their injection drug use and/or may delay care even when faced with potentially vision- and/or life-threatening conditions.

Endogenous endophthalmitis and other ocular manifestations of injection drug use.

PURPOSE OF REVIEW: The United States has experienced a dramatic rise in opioid and injection drug use over the past 2 decades. A public health emergency was declared in 2017 and subsequently, there have been several new reports on the rise of endogenous endophthalmitis specifically associated with injection drug use. The purpose of this review is to provide a current perspective of the ocular harms posed by injection drug use. RECENT FINDINGS: The opioid epidemic has prompted several new studies from New England, one of the US regions most heavily affected, that examine the trends and characteristics of injection drug use-associated endogenous endophthalmitis. Patients may delay seeking care and may be infected with a variety of rare and atypical microbes, and as a result clinical appearance may vary widely. Injection drug use also leads to embolic phenomena such as talc retinopathy and septic emboli from endocarditis. HIV is highly associated with injection drug use and although HAART has drastically reduced the morbidity and mortality of HIV-associated infections, a variety of ocular disease may accompany an immunocompromised patient. SUMMARY: Healthcare providers must remain vigilant in the recognition of injection drug use patients with vision loss and ocular inflammation to ensure prompt medical and/or surgical treatment.

Novel early response genes in osteoblasts exposed to dynamic fluid flow.

Cyclic mechanical loads applied to the skeleton from habitual physical activity result in increased bone formation. These loads lead to dynamic pressure gradients and oscillatory flow of bone interstitial fluid, which, in turn, exposes cells resident in the bony matrix to oscillatory fluid shear stress. Dynamic fluid flow has previously been shown to be a potent anabolic stimulus for cultured osteoblasts. In this study, we used cDNA microarrays to examine early phase, broad-spectrum gene expression in MC3T3-E1 osteoblasts in response to physical stimulation. RNA was harvested at 30 min and 1 h post-stimulation. RNA was used for microarray hybridization as well as subsequent reverse transcription polymerase chain reaction (RT-PCR) validation of expression levels for selected genes. Microarray results were analysed by both functional and expression profile clustering. We identified a small number of genes at both the 30 min and 1 h timepoints that were either upregulated or downregulated with flow compared to no-flow control by twofold or more. From the group of genes upregulated at 30 min, we selected nine for RT-PCR confirmation. All were found to be upregulated by at least twofold. We identify a novel set of early response genes potentially involved in mediating the anabolic response of MC3T3 osteoblasts to flow, and provide functional groupings of these genes that may shed light on the relevant mechanosensory pathways involved.

The role of actin cytoskeleton in oscillatory fluid flow-induced signaling in MC3T3-E1 osteoblasts.

Fluid flow due to loading in bone is a potent mechanical signal that may play an important role in bone adaptation to its mechanical environment. Previous in vitro studies of osteoblastic cells revealed that the upregulation of cyclooxygenase-2 (COX-2) and c-fos induced by steady fluid flow depends on a change in actin polymerization dynamics and the formation of actin stress fibers. Exposing cells to dynamic oscillatory fluid flow, the temporal flow pattern that results from normal physical activity, is also known to result in increased COX-2 expression and PGE(2) release. The purpose of this study was to determine whether dynamic fluid flow results in changes in actin dynamics similar to steady flow and to determine whether alterations in actin dynamics are required for PGE(2) release. We found that exposure to oscillatory fluid flow did not result in the development of F-actin stress fibers in MC3T3-E1 osteoblastic cells and that inhibition of actin polymerization with cytochalasin D did not inhibit intracellular calcium mobilization or PGE(2) release. In fact, PGE(2) release was increased threefold in the polymerization inhibited cells and this PGE(2) release was dependent on calcium release from the endoplasmic reticulum. This was in contrast to the PGE(2) release that occurs in normal cells, which is independent of calcium flux from endoplasmic reticulum stores. We suggest that this increased PGE(2) release involves a different molecular mechanism perhaps involving increased deformation due to the compromised cytoskeleton.

Effects of short-term recovery periods on fluid-induced signaling in osteoblastic cells.

It is well known that cyclic mechanical loading can produce an anabolic response in bone. In vivo studies have shown that the insertion of short-term recovery periods (10-15 s) into mechanical loading profiles led to an increased osteogenic response compared to continuous cyclic loading of bone. Although this is suggestive of temporal processing at the bone cell level, there is little evidence to support such a hypothesis. Therefore, the current study investigated the cellular mechanism of bone's response to rest inserted vs. continuous mechanical loading. Cell responses to rest inserted mechanical loading were quantified by applying oscillatory fluid flow (OFF) to osteoblastic cells and quantifying real-time intracellular calcium [Ca2+]i, prostaglandin E2 (PGE2) release, and osteopontin (OPN) mRNA levels. Cells were exposed to OFF (1 Hz) at shear stresses of 1 and 2 Pa with rest periods of 5, 10, and 15s inserted every 10 loading cycles. The insertion of 10 and 15s rest periods into the flow profile resulted in multiple [Ca2+]i responses by individual cells, increased [Ca2+]i response magnitudes, and increased overall percent of cells responding compared to continuously loaded control groups. We determined the source of the multiple calcium responses to be from intracellular stores. In addition, rest inserted OFF led to similar levels of PGE2 release and increased levels of relative OPN mRNA compared to cells exposed to continuous OFF. Our study suggests that the cellular mechanism of bone adaptation to rest inserted mechanical loading may involve modulation of intracellular levels of calcium (frequency, magnitude, percent of cells responding).

Oscillatory fluid flow affects human marrow stromal cell proliferation and differentiation.

Mechanical loading is an important regulator of bone formation and bone loss. Decreased osteoblast number and function are important cellular mechanisms by which mechanical disuse leads to decreased bone formation. Decreased osteoblast number may be a result of decreased osteoprogenitor proliferation, differentiation, or both. However, the effects of cellular level physical signals on osteoprogenitors are not well understood. In this study, we examined the effects of loading induced oscillatory fluid flow (OFF), a potent regulator of osteoblastic cell function, on marrow stromal cells (MSCs). MSCs subjected to OFF exhibited increased intracellular Ca2+ mobilization. In addition, MSCs exhibited increased proliferation and increased mRNA levels for osteopontin and osteocalcin genes. Collagen I and core binding factor 1 mRNA levels did not change. MSCs subjected to OFF also exhibited decreased alkaline phosphatase activity. These results suggest that MSCs are mechanosensitive and that Ca2+ may play a role in the signaling pathway.