Outcomes of refractive error correction in pseudophakic patients using a sulcus piggyback intraocular lens

PURPOSE

The purpose of this study was to assess the results of a sulcus intraocular lens (Sulcoflex) for pseudophakic refractive errors following phacoemulsification cataract surgery.

METHODS

This retrospective clinical observational cohort study included consecutive eyes in which a Sulcoflex was implanted. Uncorrected distance visual acuity and corrected distance visual acuity as well as refractive outcomes were assessed. The minimum follow-up time required for inclusion was 3 months.

RESULTS

In total, 15 eyes (n = 15) were evaluated. The mean follow-up was 14 months (range: 3-18 months). The Sulcoflex aspheric (653L) was implanted in 13 eyes and the Sulcoflex toric (653T) in two eyes. The preoperative mean logMAR (Snellen) uncorrected distance visual acuity and corrected distance visual acuity were 0.88 (20/150) and 0.27 (20/40), respectively. The postoperative mean logMAR (Snellen) corrected distance visual acuity was 0.15 (20/30). The preoperative mean spherical equivalent was -0.22 ± 5.95 D and the postoperative mean spherical equivalent was -1.59 ± 1.45 D. There was a significant and strong correlation (r = 0.64, p < 0.001) between the attempted and the achieved spherical equivalent.

CONCLUSION

The Sulcoflex is a safe and viable option for patients with residual refractive error following cataract surgery.

Retinal Toxicity of Intravitreal Injection of Ziv-Aflibercept in Albino Rabbits

Purpose

To evaluate retinal toxicity of ziv-aflibercept, a drug that had been approved for use for patients with colon cancer.

Methods

Twenty-two albino rabbits were injected intravitreally with 0.1 mL of ziv-aflibercept solution into the experimental eye and 0.1-mL saline into the control eye. Twelve were used for electroretinogram (ERG) at 4-weeks follow-up. An additional 10 rabbits were used for testing penetration of ziv-aflibercept into the retina during follow-up. The visual-evoked potential (VEP) was recorded after 4 weeks of ERG follow-up. Glial fibrillary acidic protein (GFAP) immunocytochemistry and retinal histology were performed after the termination of the follow-up period.

Results

The ERG responses of the experimental eyes did not show signs of permanent functional damage. The VEP responses of the experimental eyes were of normal pattern and amplitude, and were similar to those recorded by stimulation of the control eyes. Histologic studies of both experimental and control eyes did not show signs of structural damage. However, GFAP expression was increased in retinal Müller cells of the experimental eyes and not of the control eyes. Retinal penetration of ziv-aflibercept, as indicated by positive antihuman immunoreactivity, was observed 1 day postinjection and was strengthened during the next 7 days. At 14 days postinjection, ziv-aflibercept was not detected.

Conclusions

Ziv-aflibercept was found to be nontoxic to the retina of rabbits based on electrophysiologic testing and histologic examination. However, GFAP immunocytochemistry suggests mild retinal stress caused by the drug.

Translational Relevance

If proven safe, ziv-aflibercept may be a new affordable treatment option in conditions involving neovascularization and macular edema.

Intravitreal Trimethoprim and Sulfamethoxazole Toxicity to the Retina of Albino Rabbits

Purpose

To evaluate retinal toxicity of intravitreal trimethoprim-sulfamethoxazole (TMP-SMX) in an albino rabbit model.

Methods

Albino rabbits (N = 10) were treated in the right eye with the maximum intravitreal dose of TMP-SMX mixture (1600 μg/8000 μg /0.1 mL), while 0.1 mL saline was injected into the vitreous of the left eye. Clinical examination and electrophysiological (electroretinogram [ERG] and visual evoked potentials [VEPs]) testing were conducted before injection, 3 days, 1, 2, and 4 weeks postinjection. Retinal structure and expression of glial fibrillary acidic protein (GFAP) were assessed from histology and immunocytochemistry respectively at the end of the follow-up period.

Results

Clinical examination was normal throughout the follow-up period. ERG responses from the experimental eyes were similar to those recorded from the control eyes, but the sum of oscillatory potentials decreased in the experimental eyes at 2 weeks postinjection. The VEP responses, elicited by stimulation of the experimental eyes, were abnormal having reduced amplitude and prolonged implicit time. Histological damage in the experimental eyes was expressed by thickness reduction of whole, outer, and inner nuclear layers. GFAP was expressed in retinal Müller cells of all experimental eyes, but none of control eyes.

Conclusions

A single intravitreal injection of TMP-SMX mixture (1600 μg/8000 μg, respectively) causes functional and structural damage to the inner retina and retinal output. Signs of retinal stress were also evident by GFAP expression in retinal Müller cells of all experimental eyes. Therefore, the use of TMP-SMX via intravitreal administration should be done with caution.

Translational Relevance

These findings highlight the risk of retinal toxicity after intravitreal injection of trimethoprim-sulfamethoxazole and emphasize that this treatment should be carefully considered.

Safety of intravitreal clindamycin in albino rabbit eyes

PURPOSE

To study the potential toxic effects of intravitreal clindamycin on the retina of albino rabbits, by assessing functional and morphological retinal changes.

METHODS

Eight albino rabbits were included in the study. In each rabbit, 1 mg/0.1 ml clindamycin was injected into the vitreous of the right (experimental) eye, and 0.1 ml saline was injected into the vitreous of the left (control) eye. The electroretinogram (ERG) was recorded before injection, 3 days, 1, 2, and 4 weeks post-injection. The visual evoked potential (VEP) was recorded 4 weeks post-injection. Clinical examination was conducted at all time points. The eyes were enucleated at the termination of the follow-up period in order to prepare the retinas for histology in order to assess retinal structure.

RESULTS

ERG and VEP responses that were recorded from the experimental eye at different times following intravitreal clindamycin injection were very similar to the corresponding responses that were recorded from the control eyes. Clinical examination was normal in all eyes, and no histological damage was observed.

CONCLUSIONS

Intravitreal injection of 1 mg clindamycin does not cause functional or morphological signs of retinal toxicity in albino rabbits, during a period of 4 weeks post-injection. These findings support the clinical use of 1 mg intravitreal clindamycin.

Effect of pupil size on biometry measurements using the IOLMaster

PURPOSE

To evaluate the effect of pupil dilation on biometric measurements and intraocular lens power calculation using the IOLMaster (Carl Zeiss Meditec).

DESIGN

Prospective, observational case series.

METHODS

In this prospective study, 2 consecutive optical biometry measurements, before and after pupil dilation, were obtained using the IOLMaster on 318 eyes of 214 patients at the cataract presurgery clinic. The parameters compared were axial length, corneal power, cylinder, and the corresponding intraocular lens power, which was calculated using the Sanders-Retzlaff-Kraff/Theoretical formula.

RESULTS

This study found no statistically significant difference before and after dilation in axial length (0.005 mm; P = .476), corneal power (0.001 diopters [D]; P = .933), or calculated intraocular lens power (0.011 D; P = .609). A statistically significant difference was shown in cylinder measurements before and after dilation (0.102 D; P < .001).

CONCLUSIONS

This study demonstrated there is no clinically significant effect of pupil dilation on the IOLMaster measurements of axial length, corneal power, and corresponding theoretical intraocular lens power calculated using the Sanders-Retzlaff-Kraff/Theoretical formula.

Diameters of retinal blood vessels in a healthy cohort as measured by spectral domain optical coherence tomography

PURPOSE

To describe a method for measuring the diameters of large retinal blood vessels by means of spectral domain optical coherence tomography.

METHODS

Prospective cohort study of 29 healthy subjects (58 eyes) who underwent a spectral domain optical coherence tomography examination. Two cubes of horizontal scans were placed at the superior and inferior borders of the disk to include the large temporal retinal vessels. Vessels diameters were measured, and an artery-to-vein ratio was calculated at 10 measurement points (480-1440 μm superiorly and inferiorly from the optic disk border).

RESULTS

The mean age of the study subjects was 41.45 ± 15.53 years. Patients had no ocular or systemic pathologies. The mean diameter of the retinal artery was 135.73 ± 15.64 μm and of the vein 151.32 ± 15.22 μm at the measurement point of 480 μm, with a gradual decrease to 123.01 ± 13.43 μm and 137.69 ± 13.84 μm, respectively, at 1440 μm. The artery-to-vein ratio was ≈ 0.9 at all points of measurement.

CONCLUSION

This is a new noninvasive method for retinal blood vessels diameter measurement using the spectral domain optical coherence tomography imaging modality. This method may aid in evaluation of retinal and systemic vascular diseases.

[Proptosis and ophthalmoplegia after cataract surgery]

We report a case of a 57 years old female presenting with proptosis, periorbital swelling and ophthalmoplegia, 4 days after an uneventful phacoemucification surgery. Visual acuity was 20/200, biomicroscopy showed mild corneal edema and anterior chamber cells with normal posterior segment. The patient was febrile with leukocytosis and elevated Levels of C-reactive protein. A head computed tomography venography scan showed left eye proptosis, bilateral paranasal sinus hyper-density with massive sinus vein thrombosis extending from the left ophthalmic vein to the left cavernous, transversal and sigmoidal sinuses, the right cavernous and sigmoidal sinuses and internal jugular veins bilaterally. Very mild infiltration was seen around the Left ophthalmic vein, with no other signs of orbital inflammation. Emergency endoscopic sinus surgery was performed followed by anticoagulation and antibiotic treatment, blood and sinus culture later grew streptococci. The therapeutic measures resulted in complete resolution of the ocular and systemic findings.

Physiological and toxicological effects of cefuroxime on the albino rabbit retina

PURPOSE

Intracameral cefuroxime was found to lower the risk of endophthalmitis after cataract surgery. The purpose of this study was to evaluate the retinal toxicity of cefuroxime in a rabbit model.

METHODS

Twenty-two albino rabbits were divided into two cefuroxime groups: low-dose (1mg/0.1 mL, n = 9) and high dose (10 mg/0.1 mL, n = 13). The right eye of each rabbit was injected with 0.1 mL cefuroxime solution (experimental eye) and the left eye with 0.1 mL saline (control eye). Electroretinogram (ERG) responses were recorded at 3 hours, 4 days, and 1, 2, and 4 weeks after injection. After 4 weeks, the rabbits were euthanized, the eyes were enucleated, and the retinas were prepared for histologic evaluation and GFAP immunostaining.

RESULTS

No functional (ERG) or histologic damage was found in rabbits in the low-dose group. In the high-dose group, a significant decrease in the ERG amplitudes of the experimental eyes was seen 3 hours after injection, followed by partial recovery during 4 weeks of follow-up. Retinal histology of experimental eyes revealed marked damage. GFAP immunoreactivity in Müller cells was expressed in rabbits belonging to both groups, although it was more extensive in the high-dose group.

CONCLUSIONS

ERG and histologic findings indicated that a dose of 1 mg cefuroxime, administered intravitreally, was not toxic to the rabbit retina. A dose of 10 mg, injected intravitreally, induced transient physiological effects, and was toxic to the rabbit retina, as was evident by the permanent reduction in the ERG responses and by the structural damage to the retina with signs of glial activation.

Electrophysiologic and retinal penetration studies following intravitreal injection of bevacizumab (Avastin)

PURPOSE

Intravitreal bevacizumab (Avastin; Genentech Inc., San Francisco, CA) is a new treatment for age-related macular degeneration. The aim of this study was to evaluate retinal penetration and toxicity of bevacizumab.

METHODS

Ten albino rabbits were injected intravitreally with 0.1 mL (2.5 mg) of Avastin into one eye and 0.1 mL saline into the fellow eye. The electroretinogram (ERG) was recorded after 3 hours, 3 days, and 1, 2, and 4 weeks. The visual evoked potential (VEP) was recorded after 4 weeks. Confocal immunohistochemistry was used to assess retinal penetration.

RESULTS

The ERG responses of the control and experimental eyes were similar in amplitude and pattern throughout the follow-up period. The flash VEP responses of the experimental eyes were of normal pattern and amplitude and did not differ from those recorded by stimulation of the control eye alone. Full thickness retinal penetration was present at 24 hours and was essentially absent at 4 weeks.

CONCLUSIONS

Bevacizumab was found to be nontoxic to the retina of rabbits based on electrophysiologic studies. Full thickness retinal penetration may explain observed clinical effects of intravitreal bevacizumab. Although it is difficult to directly extrapolate to humans, our study supports the safe use of intravitreal bevacizumab injection.

Crystals in pulmonary cytologic preparations in association with aspiration of barium. A case report

Crystals were found in a pulmonary cytologic preparation in association with the aspiration of barium. This type of event has not been described previously, although rare occurrences of crystals in pulmonary cytology specimens in association with Aspergillus infection and other situations have been reported. We recommend that patients suspected of aspiration be given no oral substances for at least 12 hours before bronchoscopy.

Skin manifestations of chronic obstructive pulmonary disease

We report skin findings in thirty patients with severe chronic obstructive pulmonary disease. This study illustrates that patients with chronic obstructive pulmonary disease have numerous skin manifestations and some of these cutaneous findings are specific for chronic obstructive pulmonary disease.

Cardiogenic hepatorenal syndrome

A variant of hepatorenal syndrome occurring in patients with chronic congestive heart failure following an episode of cardiogenic pulmonary edema, and in the absence of hypotension, is described. This was observed in 13 patients during an eleven-year period. The clinical picture is characterized by hepatic injury and functional renal impairment. Increase of serum glutamic oxaloacetic transaminase levels as high as 2100 IU; prolongation of prothrombin time; elevation of serum bilirubin, creatinine, blood urea nitrogen, and potassium levels; decrease in urinary sodium excretion; and a normal urinary sediment are the salient laboratory abnormalities of this entity. Treated with conventional medication, the patients' course was fatal in 4 cases. When the splanchnic vasodilator dopamine was added to the patients' management, 5 of 9 patients recovered. Cardiogenic hepatorenal syndrome is a severe but potentially reversible complication of heart failure. The apparently beneficial effect of low-dose dopamine needs further evaluation.

Diffuse lymphangioma with intrathoracic involvement

A case of a young girl with oligosymptomatic multiple cystic lesions of the chest is presented. The chest lesions were found on routine chest X-ray when she was admitted because of meningococcal meningitis. As the lesions increased in size, surgery was performed; the operative specimens were identified as lymphangioma. This is a rare disorder, which presents difficulties in diagnosis and treatment. Its benign nature is challenged by its tendency to recur and the need for repeated operations.

Recurrent cavitary nodules secondary to Hodgkin's disease

A patient with nodular sclerosing Hodgkin's disease had at least three episodes of lung involvement consisting of an infiltrate on one occasion and multiple cavitating nodules on the other two. The cytologic and histologic studies of the lung specimens disclosed the presence of Reed-Sternberg cells on each occasion without any evidence for infection. This represents the first time in which recurrent cavitating nodules have been reported with Hodgkin's disease.

Catamenial pneumomediastinum

A patient with known pelvic endometriosis suffered from recurrent episodes of retrosternal pain in the chest at the time of menstruation. Evaluation during an episode revealed subcutaneous emphysema of the neck and a pneumomediastinum without pneumothorax. This is the first report in the English literature of pneumomediastinum due to endometriosis which was probably recurrent.

Possible female preponderance in prenylamine-induced 'torsade de pointes' tachycardia. Short communication

Episodes of ventricular tachycardia of the 'torsade de pointes' (VTTP) types provoked by prenylamine were observed in 7 patients: 5 females and 2 males. They all received prenylamine in a dose of 120-180 mg daily for anginal pains. Syncope or syncopal equivalents occurred in all 7 patients. Q-T intervals ranged from 0.52 to 0.64 s. Review of the literature revealed 11 patients with prenylamine-induced VTTP, of whom 8 were females. The female preponderance (72.2%), hitherto not commented upon in the literature, is highlighted. Prenylamine-indiced VTTP may appear late after initiation of therapy, consequently clinical and ECG long-term follow-up is mandatory. The drug should promptly be discontinued in symptomatic patients, and particularly in females showing prolonged Q-T.

Exercise testing in mitral valve prolapse before and after beta blockade

Exercise electrocardiograms must be interpreted with the understanding that not every positive test is indicative of coronary artery disease. Mitral valve prolapse mimics coronary heart disease clinically and often in the electrocardiographic response to exercise. Twelve patients with mitral valve prolapse in whom exercise testing was positive underwent a repeat study after beta blockade. All tracings returned to normal after adequate blockade, evidenced by 17 to 22% reduction of resting and exercise heart rates. To the best of our knowledge, this is the first such report in the English literature. The results of this study suggest that an exercise test after beta blockade should become part of the routine procedure in such patients. The elimination of false positive electrocardiographic responses by beta blockade should help improve the specificity of the exercise test. Moreover, similar responses should lead to the suspicion of mitral valve prolapse.