Comparing Eyesi Virtual Reality Simulator and Traditional Teaching Methods for Direct Ophthalmoscopy: Students' Perspectives at Indiana University School of Medicine.

Background The fundus examination is an essential part of any ophthalmologic evaluation. However, medical students and primary care physicians often lack confidence with direct ophthalmoscopy. Virtual reality simulators are being employed in medical education to teach this technically challenging examination. Objective To compare medical student ratings of the Eyesi Direct Ophthalmoscope Simulator and traditional small group teaching methods for learning direct ophthalmoscopy skills. Methods All medical students at Indiana University School of Medicine traditionally learn direct ophthalmoscopy in their first 2 years during a small group session led by a physician instructor. Students who later enrolled in ophthalmology clinical electives during 2019 and 2020 were invited to additionally complete the Eyesi Direct Ophthalmoscope Simulator virtual reality curriculum. A voluntary, anonymous survey was sent between June and August 2020 to students who had completed both the traditional and Eyesi simulator sessions. Students were asked to rate their confidence in performing direct ophthalmoscopy following each session, and to indicate which teaching method was superior and why. Chi-square analysis was used to compare categorical variables. Results Students' confidence ratings for performing direct ophthalmoscopy were significantly higher following completion of the Eyesi simulator session compared with the traditional small group session ( p < 0.001). Four-fifths of respondents felt that the Eyesi simulator was superior to the traditional small group for learning the skills of direct ophthalmoscopy, while one-fifth felt that the two sessions were equally effective ( p < 0.001). None of the students responded that the small group session was the superior teaching method. Conclusion The Eyesi Direct Ophthalmoscope Simulator was rated highly among medical students and offers distinct learning advantages that could not be replicated in a traditional small group environment, such as providing numerous examples of pathological findings and allowing unlimited examination time without concern for patient's inconvenience or light exposure. The Eyesi simulator is a promising tool for teaching direct ophthalmoscopy to medical students. Ultimately, familiarity with the fundus examination will enable future physicians across specialties to better evaluate and appropriately refer patients with ocular fundus pathology.

Ocular penetration of levofloxacin, ofloxacin and ciprofloxacin in eyes with functioning filtering blebs: investigator masked, randomised clinical trial.

BACKGROUND/AIMS: To compare the penetration of levofloxacin, ofloxacin and ciprofloxacin in the aqueous humour of eyes with functioning filtering blebs. METHODS: In this investigator-masked study, 48 patients with functioning filtering blebs requiring cataract surgery were randomised into six groups of eight patients. Groups 1, 2 and 3 received topical ofloxacin 0.3% (Ocuflox), ciprofloxacin 0.3% (Ciloxan) and levofloxacin (Quixin) respectively; Groups 4, 5 and 6 received the same treatment with the corresponding oral dose of ofloxacin 400 mg (Floxin), ciprofloxacin 400 mg (Cipro) and levofloxacin 250 mg (Levaquin). Aqueous antibiotic levels were determined by mass spectrometry of aqueous samples from each patient. RESULTS: The mean aqueous level for topical levofloxacin was significantly higher than those achieved by topical ofloxacin or ciprofloxacin (p value = 0.02 and 0.01, respectively). The combination of topical and oral levofloxacin was significantly higher than topical levofloxacin alone (p = 0.05) and the ciprofloxacin combination (p = 0.003) but not significantly higher than the ofloxacin combination therapy. CONCLUSIONS: Topical levofloxacin penetrates better than ofloxacin or ciprofloxacin into the aqueous of eyes with functioning filtering blebs. The combination of topical and oral levofloxacin may be preferable in the treatment of bleb-associated infections (NCT 00392275; Clinical trials.gov).

Transglutaminase crosslinked gelatin as a tissue engineering scaffold.

Gelatin is one of the most commonly used biomaterials for creating cellular scaffolds due to its innocuous nature. In order to create stable gelatin hydrogels at physiological temperatures (37 degrees C), chemical crosslinking agents such as glutaraldehyde are typically used. To circumvent potential problems with residual amounts of these crosslinkers in vivo and create scaffolds that are both physiologically robust and biocompatible, a microbial transglutaminase (mTG) was used in this study to enzymatically crosslink gelatin solutions. HEK293 cells encapsulated in mTG-crosslinked gelatin proliferated at a rate of 0.03 day(-1). When released via proteolytic degradation with trypsin, the cells were able to recolonize tissue culture flasks, suggesting that cells for therapeutic purposes could be delivered in vivo using an mTG-crosslinked gelatin construct. Upon submersion in a saline solution at 37 degrees C, the mTG-crosslinked gelatin exhibited no mass loss, within experimental error, indicating that the material is thermally stable. The proteolytic degradation rate of mTG-crosslinked gelatin at RT was slightly faster than that of thermally-cooled (physically-crosslinked) gelatin. Thermally-cooled gelatin that was subsequently crosslinked with mTG resulted in hydrogels that were more resistant to proteolysis. Degradation rates were found to be tunable with gelatin content, an attribute that may be useful for either long-time cell encapsulation or time-released regenerative cell delivery. Further investigation showed that proteolytic degradation was controlled by surface erosion.

The response of retrobulbar vasculature to hypercapnia in primary open-angle glaucoma and ocular hypertension.

PURPOSE: To evaluate the physiological effects of hypercapnia on the retrobulbar vasculature in ocular hypertension (OH) and open-angle glaucoma (OAG). METHODS: Peak systolic velocity (PSV), end-diastolic velocity (EDV) and resistive index (RI) of the ophthalmic (OA) and central retinal arteries (CRA) were evaluated in 12 eyes with OH and 8 eyes with OAG using color Doppler imaging. Measurements were taken before and during hypercapnia. RESULTS: Patients with OAG were found to have increased EDV (p < 0.035) of the CRA, and decreased PSV (p < 0.097) and EDV (p < 0.098) of the OA, during hypercapnia. Patients with OH had increased PSV (p < 0.062) and EDV (p < 0.072) of the CRA during hypercapnia. Patients with OH also demonstrated a greater percent change in the calculated RI (p < 0.065) of the CRA in response to hypercapnia when compared to OAG. The mean RI of the CRA decreased during hypercapnia. DISCUSSION: Patients with OH were found to have a normal vasodilatory response within the retrobulbar vasculature during hypercapnia resulting in increased volumetric blood flow to the retina while patients with OAG did not, suggesting there is vasospasm at or downstream from the CRA resulting in decreased volumetric blood flow to the retina.

Macular pigment optical density before and after cataract extraction.

PURPOSE: Psychophysical methods of measuring macular pigment (MP) use comparisons of short- and midwave light in the fovea and parafovea to derive optical density estimates. This light must pass through the crystalline lens before absorption by the MPs can occur. The effect of lens absorption on these measures has not been adequately determined. The present study assesses the influence of lens absorption on MP measurements by comparing MP optical density (MPOD) measured before and after cataract extraction. METHODS: MPOD was measured using flicker photometry in free view at 458 nm with a 1 degrees stimulus. Twenty-nine eyes from 24 patients with cataracts sufficiently severe to require cataract extraction were evaluated. RESULTS: In the entire group of 24 patients, the mean (+/-SD) age measured 68.7 +/- 9.5 years, and the mean MPOD measured 0.19 +/- 0.11. For all 29 eyes measured, MPOD averaged 0.206 +/- 0.13 before and 0.18 +/- 0.12 after cataract extraction. MPOD measurements at the two time points (mean 8.1 +/- 4.7 weeks after surgery) were highly correlated (r = +0.58), suggesting that a cataractous lens does not influence the MP measurement technique. CONCLUSIONS: Psychophysical techniques can be used to obtain reliable measurements of MP in elderly subjects, even in those with cataracts. Moreover, differences in retinal illuminance due to varying opaqueness of the crystalline lens do not seem to have a measurable influence on MPOD.

Silicone intraocular lens encapsulation by shrinkage of the capsulorhexis opening.

We report a case of an 80-year-old woman who developed complete opacification and contraction of the continuous curvilinear capsulorhexis opening 4 months after having phacoemulsification and implantation of a silicone plate-haptic intraocular lens. We performed a neodymium:YAG laser capsulotomy without complication.

Talc embolism: a static retinopathy.

PURPOSE: To document the static nature of crystalline deposits in talc retinopathy. METHOD: Case report. RESULTS: A 38-year-old woman with a remote history of intravenous drug abuse showed the incidental finding of fine, irregularly shaped refractile deposits in the retinal microvasculature. At 2-year follow-up, fundus findings were identical to the initial manifestation with respect to the distribution and position of crystalline deposits in each fundus. CONCLUSION: This case documents the static nature of crystalline deposits in talc retinopathy.

Spontaneous resolution of an endocapsular hematoma.

PURPOSE: To report a case of endocapsular hematoma that cleared spontaneously without intervention. METHODS: We examined and followed up a 68-year-old man who developed an endocapsular hematoma 2 1/2 years after a standard extracapsular cataract extraction with posterior chamber intraocular lens implantation. RESULTS: After several months without intervention, the endocapsular hematoma completely resolved. CONCLUSIONS: Observation may be a rational treatment option in some patients with endocapsular hematoma.

Retinal blood flow indices in patients infected with human immunodeficiency virus.

AIMS/BACKGROUND: Abnormal blood flow dynamics are believed to contribute to the development of retinal microvascular disease in patients infected with human immunodeficiency virus (HIV). In this study, the scanning laser ophthalmoscope (SLO) was used, combined with fluorescein angiography, to measure retinal blood flow indices in HIV seropositive patients. METHODS: Arteriovenous passage time (AVP) and perifoveal capillary blood flow velocity (CFV) were measured in 23 HIV infected patients and 23 control subjects with SLO fluorescein angiography. RESULTS: No significant difference in AVP was found between the two groups. However, CFV was significantly reduced in HIV infected patients (p = 0.013). CONCLUSION: Patients infected with HIV show abnormal haemodynamics at the level of the perifoveal capillaries.

Patterns of diabetic eye care by primary care physicians in the state of Indiana.

Diabetic retinopathy is the leading cause of new blindness in the 20 to 74-age group in the United States. The American Academy of Ophthalmology (AAO) and American Diabetes Association (ADA) have recommended guidelines for eye examination to assist primary care physicians in managing these patients. The purpose of this study is to investigate the patterns of diabetic eye care offered by primary care physicians in the State of Indiana. A survey questionnaire was sent to 1279 primary care physicians in central Indiana. Of those surveyed, 259 (20%) responded. Thirty-five percent of respondents stated that they never refer patients for ocular examination while 26% refer all patients. The remainder refer on a case-by-case basis. Patients who are not referred have their fundus examined only 70% of the time by the primary care physician and 96% of these examinations are performed with an undilated pupil. When referred, 20% of Type I patients are referred at the time of diagnosis and 50% by one year. Of the Type II patients, only 2% are referred at the time of diagnosis and 70% by one year. Ophthalmologists receive 75% of the referrals while optometrists receive 20%. Our results show that a significant number of primary care physicians in the State of Indiana do not follow the recommended guidelines set forth for diabetic eye care.

Posterior lens dislocation during attempted phacoemulsification.

Mechanisms of posterior lens dislocation during phacoemulsification have been suggested, but the actual mechanism involved has not been demonstrated. Chart reviews of cataract surgeries performed at Indiana University from 1991 until the present identified nine cases of posterior lens dislocation that occurred during phacoemulsification. In four, the procedure was converted early to a can-opener capsulotomy. Cadaver eye studies showed the role of an imperfect capsulorhexis in extending tears while a "trap door" was being formed for posterior nuclear dislocation during phacoemulsification.

Prospective comparison of the Heine retinometer with the Mentor Guyton-Minkowski potential acuity meter for the assessment of potential visual acuity before cataract surgery.

Various techniques and devices have been developed to aid in the assessment of potential visual acuity prior to cataract surgery. We report a prospective comparison of two such assessments, one made using a new instrument, the hand-held Heine retinometer (HR) (Heine Instruments, Germany), and the other using the Mentor Guyton-Minkowski potential acuity meter (PAM) (Mentor, Inc, Norwell, Mass). A total of 37 eyes were assessed using both instruments just before cataract surgery. Three eyes were excluded from analysis due to postoperative complications affecting visual acuity that could not have been predicted with either instrument. The false-negative rate was 44% for the PAM and 32% for the HR. There were no false-positive results with either instrument. Neither instrument was particularly accurate in predicting actual final visual acuity (r2 = 0.290 and 0.144 for the PAM and HR, respectively). The HR was deemed easier to use.

Argon laser treatment of trichiasis: a clinical and histopathologic evaluation.

Trichiasis is a common condition of multiple etiologies. Cryosurgery has been advocated as an effective means of treatment but may be associated with serious complications, including scar, skin depigmentation, and lid notching. We treated eight consecutive eyelids with the argon laser. At the end of a 3-month follow-up period, no recurrence was noted. The only observed complication was mild eyelid notching in one eyelid. Histopathologic evaluation of two specimens obtained 10 days and 5 weeks after laser treatment confirmed the highly localized coagulative effect of the laser with minimum destruction of adjacent tissues. Orientation of the eyelid so that the laser beam and the lash follicle are coaxial and careful measurement of the depth of vaporization of the lash follicle are important in confirming complete treatment and minimizing recurrence.

Efficacy of lateral canthotomy and cantholysis in orbital hemorrhage.

Emergent orbital decompression in tense orbital hemorrhage with compromised ophthalmic blood flow may be achieved with lateral canthotomy, defined as incision of the lateral canthal tendon, and cantholysis, defined as canthotomy combined with disinsertion of at least the inferior crus of the lateral canthal tendon. This study was performed to determine which procedure, canthotomy, canthal tendon disinsertion, or cantholysis, produced the largest reduction in intraocular pressure after simulated orbital hemorrhage in 10 closed ruminant orbits with retrobulbar injections of normal saline. Intraocular pressure (IOP) reductions were measured after canthotomy in five orbits, after lateral canthal tendon disinsertion in five orbits, and after completion of cantholysis in all 10 orbits. Canthotomy produced a mean IOP reduction of 14.2 mm Hg. Canthal tendon disinsertion (CTD) produced a mean IOP reduction of 19.2 mm Hg. Cantholysis produced a mean IOP reduction of 30.4 mm Hg, a significantly (p < 0.05) greater reduction in IOP than that produced by canthotomy or canthal tendon disinsertion alone. Cantholysis in acute orbital hemorrhage may produce significantly greater reduction in IOP, and thus in intraorbital pressure, and allow better perfusion of orbital tissues than either lateral canthotomy or CTD.

Spontaneous orbital subperiosteal hematomas in patients with liver disease.

Spontaneous orbital subperiosteal hematomas are rare entities. They are often associated with systemic coagulopathies. We present two cases of spontaneous orbital subperiosteal hematomas in patients with systemic coagulopathies resulting from liver disease. One patient was diagnosed with hepatitis B and had spontaneous resolution of the hematoma. Another patient had alcoholic cirrhosis and required an orbitotomy for drainage of a hematoma for compressive optic neuropathy. With the rising incidence of hepatitis B and the prevalence of alcoholic liver disease, it is important to include liver disease in the systemic evaluation of patients with spontaneous orbital subperiosteal hematomas.

Antibiotic responsive exophthalmos and lateral rectus paralysis.

Sinusitis is an unusual cause of exophthalmos in adults since the advent of antibiotics. Many periorbital complications of sinusitis have been described; however exophthalmos associated with apparent sixth cranial nerve palsy in the absence of ipsilateral sphenoidal sinusitis is a rare and, to our knowledge, unreported complication of sinusitis. We report such a case that was treated with oral antibiotics. We believe that sinusitis must always be considered in adults as a treatable cause of exophthalmos and various orbital complications from isolated lateral rectus paralysis to acute-onset, acquired Brown's syndrome.

Cells that mediate NK like cytotoxicity are present in the human delayed type hypersensitivity response.

By inducing delayed type hypersensitivity (DTH) responses under previously formed skin blisters we determined that cells which mediate natural killer (NK) like cytotoxicity are present in the DTH response in man. Similar levels of killing were not present in cells obtained from skin blisters not associated with positive DTH responses. The DTH response associated killer cell was found to be a mononuclear cell that had presumably undergone stimulation since it not only killed NK sensitive K-562 cells, but also NK resistant Daudi target cells.

Reduced threshold to suction-induced blister formation in insulin-dependent diabetics.

Diabetics may have an increased susceptibility to cutaneous blister formation clinically manifest as the bullous eruption of diabetes. We evaluated the mechanical force necessary to induce suction blisters in fifteen insulin-dependent diabetics and twenty age-matched normal controls. The mean suction blister threshold for the diabetics was 31.9 minutes versus 68.0 minutes for the controls, a highly significant difference (p less than 0.01). Histologic appearance of suction blisters was similar in diabetic and normal skin, under both light and electron microscopic examination, with a noninflammatory subepidermal separation in the lamina lucida between the cell membrane and the basal lamina. These results demonstrate that insulin-dependent diabetics have a marked reduction in suction blister threshold as compared to age-matched controls.

Heparin-induced cutaneous necrosis unrelated to injection sites. A sign of potentially lethal complications.

Skin necrosis is a rare complication of heparin administration that is usually localized to injection sites. A 32-year-old insulin-dependent diabetic patient, receiving intravenous (IV) and low-dose heparin sodium therapy, had cutaneous necrosis in areas distant to the sites of injection. Prior to the onset of cutaneous lesions, thrombocytopenia develop]ed in the patient that may have been heparin induced. Heparin may induce the production of platelet aggregating immunoglobulins that predispose persons who are sensitive to the drug to thrombocytopenia, skin necrosis, and thrombotic events. Obesity, diabetes, and treatment with broad-spectrum antibiotics seem to increase the risk of such complications. Cutaneous necrosis secondary to heparin administration may serve as a warning of the potentially lethal complications of IV use. In patients in whom skin necrosis or thrombocytopenia develops, heparin therapy should be discontinued and anticoagulation with an oral agent should be considered.

Familial severe twenty-nail dystrophy.

Severe nail dystrophy is a recently described acquired nail disorder. The nails are variably involved and may show thinning, thickening, pitting, ridging, koilonychia, opalescence, and loss of luster. Not uncommonly, some nails are completely spared. Although most of the cases reported were among children, and nail changes showed gradual resolution, in a few cases the disorder is seen in adulthood. We recently investigated a pedigree extending through five generations in which twenty-one of the thirty-seven members were variably afflicted with the dystrophic nail changes. To our knowledge, the familial pattern, inherited as an autosomal dominant trait, has never been previously reported. We propose the term "familial severe twenty-nail dystrophy" for the disorder in this family.