Vitrectomy Results for Diffuse Diabetic Macular Edema with and without Inner Limiting Membrane Removal

Purpose

To determine whether vitrectomy for diffuse diabetic macular edema with and without internal limiting membrane (ILM) peeling is equally effective in reducing edema.

METHODS

The authors retrospectively analyzed the surgical outcomes in 73 eyes of 52 patients with diffuse diabetic macular edema. Eighteen eyes (Group A) underwent three-port pars plana vitrectomy with posterior hyaloid membrane (PHM) removal, while 55 eyes (Group B) had pars plana vitrectomy with additional ILM peeling after PHM removal. RESULTS. Intraoperatively the posterior hyaloid was found to be attached to the macula in all eyes. In Group A, macular edema resolved completely in 8 eyes (44.4%) with improvement of visual acuity (VA). In Group B, VA improved in 38 eyes (69.1%) with complete resolution of edema. The results of this study indicated that vitrectomy effectively reduced macular edema but eyes with ILM peeling (Group B) presented better results than those without ILM peeling. Another important factor related to the outcome seems to be the level of glycosylated hemoglobin (HbA1c).

CONCLUSIONS

In eyes with diffuse diabetic macular edema vitrectomy seems to be effective, but additional ILM peeling presented better results.

Prediction of gas chromatographic retention indexes for polychlorinated dibenzofurans

A model has been developed by using molecular connectivity to describe the relationship between the molecular structure of polychlorinated dibenzofurans (PCDFs) and their gas chromatographic linear temperature-programmed retention characteristics on a 30-m fused silica column coated with a DB-5 stationary phase. Model variables account for the number of chlorine atoms present, the position and the relationship on each aromatic ring, the chlorine atom interaction between the two rings, and the skeletal structure of each PCDF isomer.

Our experience with perfluorohexyloctane (F6H8) as a temporary endotamponade in vitreoretinal surgery

PURPOSE

To evaluate the use of F6H8 as a temporary endotamponade for complicated and special cases of retinal detachment instead of silicone oil.

METHODS

We have used F6H8 with 14 patients since February 1999. Eight suffered from rhegmatogenous retinal detachment (RRD) with multiple tears located inferiorly. Three presented inferior traction retinal detachment (TRD) under silicone oil, two suffered from ocular trauma with inferior TRD, and one had idiopathic macular hole. The substance was introduced into the eye after pars plana vitrectomy and membrane peeling if needed, and we tried to introduce as much as possible.

RESULTS

With F6H8 the retina was easily reattached in all cases, like with perfluorocarbon liquids. The postoperative view was very good. F6H8 was removed in all cases after 3-8 weeks. Anatomical success was achieved in 12 out of 14 eyes. Two eyes presented severe PVR. F6H8 entered the anterior chamber in 4 cases, but no corneal complications occurred. In one case there was a marked IOP rise due to an anterior block, treated with superior iridotomy. In two cases retinal detachment (RD) occurred in the upper part and was treated with additional surgery, F6H8 removal and silicone oil injection.

CONCLUSIONS

F6H8 seems to be a promising tamponade agent for special cases of RD.

Silicone Intubation as an Alternative to Dacryocystorhinostomy for Nasolacrimal Drainage Obstruction in Adults

Silicone tubing was used to repair the patency of the nasolacrimal drainage system in 115 patients (four bilaterally) with chronic nasolacrimal duct obstruction. The patients were over 20 years old and 16 were men and 99 women; 46% presented an uncomplicated obstruction with epiphora and 54% presented additional signs of chronic dacryocystitis. We used the technique of Quickert and Dryden with modifications. The silicone tube remained for a mean of 5.5 months (± 2.5 SD). After removal of the tube the follow-up ranged from 6 to 42 months (mean ± SD: 16 ± 9). Patency was maintained in 89% of cases with uncomplicated obstruction and in 69% of those with chronic dacryocystitis (total success rate 78%). We can therefore recommend silicone intubation of the lacrimal drainage system as an alternative to dacryocystorhinostomy (DCR), in adults with obstruction of the nasolacrimal duct. In addition, unlike DCR this technique is bloodless and the operation takes less time.

Metabolic abnormalities in patients with primary open-angle glaucoma

PURPOSE

Although there are few data on the underlying mechanisms of primary open-angle glaucoma (POAG), it has been suggested that metabolic diseases may play a role in the evolution of the disease. We carried out the present study to investigate the involvement of metabolic disturbances in POAG pathogenesis.

MATERIAL/METHODS

Serum metabolic parameters were evaluated in 49 POAG patients without a known history of diabetes mellitus and 72 age and sex matched individuals without glaucoma (control group).

RESULTS

Among the metabolic parameters examined, only fasting serum glucose and uric acid levels were found significantly higher in patients with glaucoma compared to the control population (117+/-17 mg/dl vs 105+/-11 mg/dl, p=0.05 and 6.2+/-1.9 mg/dl vs 5+/-1.2 mg/dl, p=0.006, respectively). Additionally, a considerably greater proportion of patients had disturbances of the carbohydrate metabolism and hyperuricemia.

CONCLUSION

We conclude that disturbances of carbohydrate and uric acid metabolism could play a role in glaucoma damage and pathogenesis.

The effect of indomethacin, diclofenac and flurbiprofen on the maintenance of mydriasis during extracapsular cataract extraction

Surgically induced miosis (SIM) frequently occurs during extracapsular cataract extraction (ECCE). A randomized clinical trial was performed to evaluate the effect of 3 nonsteroidal antiinflammatory drugs Indomethacin 1%, Diclofenac 0.1% and Flurbiprofen 0.03%, administered topically before ECCE, on the maintenance of mydriasis during surgery. The patients were grouped based on the type of NSAID given preoperatively in addition to the standard mydriatic agents: 46 patients in group A (Indomethacin), 40 patients in B (Diclofenac), 44 patients in C (Flurbiprofen) and 34 patients formed control group D (no NSAID was instilled). Horizontal pupillary diameter measurements were taken, using a caliper, immediately prior to surgery (step 0), after capsulotomy (step I), after expression of the lens nucleus (step II) and after irrigation-aspiration of the cortical remnants (step III). Differences in pupillary diameter between step 0 and the different surgical steps were used as indices of pupillary constrictions observed in the 4 groups. A significantly less pupillary constriction was found in groups A and C than in D between steps 0 and II (p = 0.01) and in groups A and C than in B and D between steps 0 and III (p = 0.001). Our results show that Indomethacin 1% and Flurbiprofen 0.03%, compared to Diclofenac 0.1% and no NSAID regime, are significantly more effective in maintaining mydriasis during cataract surgery.

The cornea in exfoliation syndrome

Exfoliation syndrome (EXS) is a disorder which affects some structures of the eye. We studied the changes of the cornea in patients with EXS and compared with those in normal persons. A prospective study of 96 consecutive patients more than 70 years of age was set up. 48 of them (70 eyes, group A) had exfoliation in one or both eyes and 48 (group B) had no ocular disease other than senile cataract. None of the patients had any systemic disease. The endothelium and thickness of the central cornea were studied. Endothelium of the eyes with EXS showed significantly (p < 0.05) lower cell density than those of group B. Cornea in group A was significantly thicker (p < 0.05) than in group B. The morphology of the endothelium in group A showed a decrease of hexagonal cells and a higher rate of polymegethism compared to group B. Corneal thickness and endothelium showed no significant differences between the eyes with EXS and normal fellow eyes. These results add another risk factor, the fragile cornea, in eyes with EXS, in cataract surgery.

Anticardiolipin antibodies and occlusive vascular disease of the eye: prospective study

There is a recognized association between the presence of anticardiolipin antibodies and vascular occlusive disease. The purpose of our study is to detect the presence of high titers of anticardiolipin antibodies (ACA) in the serum and to correlate the titers with the severity of the vascular disease in patients with occlusive ocular vascular disease. 82 patients were included in a prospective study; 25 patients with anterior ischaemic optic neuropathy, 36 with retinal vein occlusion and 21 with retinal artery occlusion. ACA (IgG and IgM isotypes) were measured by ELISA in the sera of all patients. The group of the patients (group A) was compared to an age-matched control group of 79 healthy individuals (group B). IgG isotype (but not IgM) titers of ACA were found significantly higher in group A (P < 0.001). In patients with titers of ACA (IgG isotype) > 100 units we noted a higher incidence of a more severe disease (recurrency, involvement of both eyes or extraocular manifestations) especially among those with anterior ischaemic optic neuropathy and secondarily in those with retinal artery occlusion. Our results suggest that the association between high titers of ACA and occlusive vascular disease of the eye concerns only the IgG isotype. In addition, the detection of high titers of IgG/AGA in patients could be a useful marker for disease severity and prognosis and this observation seems to be more explicit in cases with arterial occlusive disease than in cases with venous occlusive disease.

Factors influencing the accuracy of the SRK formula in the intraocular less power calculation

Several intraocular lens (IOL) power calculation formulas (either theoretical or empirical) are used to determine the emmetropic IOL power) The Sanders-Retzlaff-Kraff (SRK) linear regression formula is among the most widely recognized empirical ones. In the present study intraocular lens power calculation aiming at emmetropia was performed, using SRK formula, in 145 cataractous eyes undergoing lens implantation. The final refraction was evaluated at 8 to 12 months after surgery. The purpose of this study was the identification and quantitative evaluation of the factors which influence significantly the accuracy of SRK in the intraocular lens power calculation. The following factors were studied: (1) the error in preoperative biometry with regard to the difference between post and preoperative axial length measurements, (2) the position of the implantation of the intraocular lens (anterior versus posterior chamber), (3) the intraocular lens style, (4) the intraocular lens power level, (5) the preoperative corneal astigmatism, (6) the surgically induced corneal astigmatism, and (7) the postoperative astigmatism. Multiple regression and stepwise regression analysis showed a strong correlation (R2 = 0.65; p < 0.001) between postoperative refractive error (Rf) and error in preoperative biometry (delta AL), surgically induced corneal astigmatism (SIA) and postoperative astigmatism (Ap) only. This correlation is expressed by the following equation: Rf = 0.07 -2.55 delta AL -0.42 SIA + 0.34 Ap. This equation indicates the quantitative effect of each factor on the accuracy of the SRK formula, by defining the pattern of the fluctuations of the amount or state (myopic or hyperopic) of refractive error induced by changes of variables delta AL, SIA and Ap.

Retinopathy of prematurity and other ocular problems in premature infants weighing less than 1500 g at birth

PURPOSE

To estimate the incidence of retinopathy of prematurity and other ocular problems in a population of preterm infants.

METHODS

This retrospective study included all infants with gestational age (GA) <32 weeks and birth weight (BW) <1500 g cared for in the neonatal intensive care unit (NICU) over a period of nine years (1992-2000). Ophthalmological examination was started the 4th week of life and included refractive examination, examination of the cornea and funduscopy under mydriasis. An ocular motility test was done after the 2nd month.

RESULTS

The study included 194 infants. Stage I and II retinopathy occurred in 51 infants but regressed spontaneously. Five of the 194 (2.5%) had to undergo cryopexy. Optic disc atrophy was observed in association with peri-intraventricular hemorrhage (PIIVH) (grade IV) in seven infants. Fifteen infants (7.7%) had retinal hemorrhages which were absorbed by three months of age. Almost 20% of the study infants developed high refractive errors and 13.4% strabismus.

CONCLUSIONS

Not only retinopathy of prematurity, but other serious ocular problems were observed in this population of preterm infants. The role of PIIVH III-IV in the pathogenesis of certain ocular problems needs further elucidation.

Association of serum inflammatory markers and diabetic retinopathy: a review of literature

OBJECTIVE

Diabetic retinopathy is the leading cause of irreversible blindness in the western world, among the working-age people. Its exact pathogenesis, however, remains obscure. Systemic inflammation is regarded to play a significant role in diabetes by contributing, among others, to the development of diabetic retinopathy. This review focuses on the possible involvement of the systemic inflammatory markers in the pathogenesis of diabetic retinopathy.

PATIENTS AND METHODS

We performed a systematic search of the literature of published papers until August 2017 using the PubMed search engine.

RESULTS

We demonstrated that many systemic inflammatory markers contribute to the pathogenesis and progression of retinopathy, while we highlighted in several occasions their usefulness as a key tool in the monitoring of the disease progression and the treatment efficacy.

CONCLUSIONS

To the best of our knowledge this is the first review in the literature that elaborates the possible association of serum inflammatory markers and diabetic retinopathy, a disease that may cause irreversible loss of vision.

Long-term visual results after laser photocoagulation for diabetic maculopathy

A study was performed to determine the long-term visual results after laser photocoagulation in diabetic maculopathy. One hundred and four eyes of 56 diabetic patients underwent modified grid laser photocoagulation for diabetic maculopathy according to the protocol of the European Study Group on Diabetic Eye Complications and the Early Treatment Diabetic Retinopathy Study. Follow-up ranged from 12 months to 2.5 years. Eyes with visual acuity less than 0.2 before treatment were included in group A, those with visual aquity of 0.3-0.6 in group B and eyes with visual acuity more than 0.7 were included in group C. At 1 year, 79.4% of the eyes of group A improved or preserved their visual acuity, with 38.9% of group B and 88.2% of group C; at 2 years, 86.6% of group A, 30% of group B and 66.7% of group C and at 2.5 years 85.7% of group A, 27.3% of group B and 75% of group C improved or preserved their visual acuity. The percentages of positive results concerning the visual acuity for groups A and C were significantly greater compared with those for group B. These results suggest that modified grid laser photocoagulation for the management of diabetic maculopathy is an effective procedure in 'early treated' eyes (visual aquity > or = 0.7). It contributes to improve a little or to preserve low vision but it did not affect the natural course of disease in the rest of the eyes.

[Morphology of early retinal lesions after experimental venous occlusion]

PURPOSE

Study of early hystological lesions after experimental branch venous occlusion (BVO) in miniature pigs.

MATERIALS AND METHODS

The retina was taken 1, 2, 4, 6 and 8 hours after BVO with green argon laser for examination with conventional and electronic microscopy.

RESULTS

1 hour after occlusion an extracellular focal oedema is observable in the ganglion cells optic nerve fibers and cells of inner plexiform layer; 2 hours after occlusion there is also an extracellular oedema of the external plexiform layer as intracellular oedema of the inner nuclear layer, 4 hours after occlusion the extracellular oedema is more diffuse especially in the ganglion cells, inner nuclear and optic nerve fibers layers. Cytoplasmic vacuolisation, nuclear pycnosis and ruptured cell membrane layers are observed; 8 hours after occlusion both intra and extracellular oedema are observable throughout the inner retina.

CONCLUSIONS

After BVO histological lesions are found within one hour only following the occlusion, apoptosis and cell necrosis are present as soon as 4 hours after experimental BVO.

Inhibition of demand pacemakers by myopotentials

The inhibition of unipolar demand pacemakers by myopotentials was studied in 215 paced patients with or without symptoms and in steady pacing rhythm. ECG recordings were taken of all patients at rest and during effort in which maximal muscular strength from the pectoralis major (PM) and rectus abdominis (RA) muscles was required. In 75 patients (34.9%) transient pacing inhibition was observed. In these patients myopotentials from the PM and RA muscles were recorded simultaneously at rest and during special effort. The PM was the dominant source of inhibiting myopotentials in 50.7% of the total patients with oversensing and the RA was dominant in 28%. In the remaining 21.3%, neither of these muscle groups alone was able to cause inhibition and a clear synergy of both the PM and RA muscles was required. When oversensing occurred in a pacemaker implanted in the thoracic wall, the PM was the dominant cause in 54.4% of patients and the RA in 23.5%, while a synergy of both muscles was required in the remaining 22%. When the pacemaker was implanted in the abdominal wall, the RA was the dominant source of inhibiting myopotentials in all but two patients.

The association between intestinal microbiome and autoimmune uveitis

INTRODUCTION AND OBJECTIVES

The microbiome is strongly implicated in a wide spectrum of immune-mediated diseases, whereas gut commensal microbiota plays a pivotal role in immune and intestinal homeostasis.

MATERIALS AND METHODS

A thorough literature search was performed in PubMed database. An additional search was made in Google Scholar to complete the collected items.

RESULTS

Due to complex interactions with the host genetics and other factors, intestinal dysbiosis has been linked to various immune-mediated disorders. In particular, the role of intestinal microbiota in the pathogenesis of uveitis has been demonstrated by several studies, indicating that changes in the microbiome can trigger autoimmune ocular inflammatory processes or affect their severity.

CONCLUSIONS

This review summarizes how alterations in the intestinal microbiota can conduce to immune-mediated ocular pathologies and how microbiome can be targeted in order to form novel therapeutic approaches to treat these severe and potentially blinding conditions.

A sphenoid en plaque meningioma aggravates exophthalmos in a patient with thyroid ophthalmopathy

PURPOSE

To describe the rare case of a patient with thyroid ophthalmopathy whose unilateral aggravated exophthalmos was caused by the development of an ipsilateral sphenoid wing en plaque meningioma.

METHODS

Case report.

RESULTS

The ophthalmologic examination included visual acuity assessment, anterior segment examination, funduscopy, ocular motility examination, and exophthalmometry. Magnetic resonance imaging (MRI) of the brain and orbit revealed the existence of a sphenoid meningioma. Removal of the tumor through a pterional craniotomy was performed. The histologic examination showed that it was an en plaque meningioma. There were no postoperative complications and no recurrence of the tumor was revealed 24 months after the operation.

CONCLUSIONS

Detailed ophthalmologic examination and MRI of the brain and orbit are necessary in every patient with deterioration of the exophthalmos even if the suggestive cause seems obvious.

[Early alterations in release of nitrogen monoxide by the retinal after experimental venous occlusion]

PURPOSE

We present hereby some results indicating that there is a significant decrease in the release of NO by the retina immediately after branch-venous occlusion (BVO).

METHODS

Using an NO microprobe we measured (NO) in the preretinal vitreous of miniature pigs before and two hours aRer bvo. Conventional and electronic microscopy were performed on the affected retina.

RESULTS

At the retinal surface (NO) was reduced to 25% of the previous value two hours after BVO, at the same time significative oedema of the inner retina was observed.

CONCLUSIONS

Immediately after BVO there is a significative decrease in the amount of NO released by the affected retina, parallel to the first evidences of an oedema of the inner retinal layers.

The effect of fish consumption on macula structure and function of healthy individuals: an OCT and mfERG study

OBJECTIVE

The study was designed to investigate the potential effect of fish consumption on macular structure and function of healthy individuals.

PATIENTS AND METHODS

The participants were Greek, who used to consume less than one portion of fish per week since their childhood. All participants underwent body mass index (BMI) measurements and ophthalmological examination. At their first examination, they were asked to consume at least 2 portions of fish per week over a period of 8 weeks, after which all the measurements were repeated.

RESULTS

Eighteen healthy individuals (36 eyes) participated in this study. The central macular thickness was reduced, while the amplitudes in the foveal and parafoveal area were increased after the fish consumption. However, all measurements remained within the normal range at both visits.

CONCLUSIONS

Regular fish consumption could enhance the structural and functional status of the macula.

Antituberculosis therapy in the treatment of peripheral uveitis

Tuberculous uveitis usually appears as chronic anterior uveitis or disseminated choroiditis. From 1982 to 1989, we conducted a retrospective study of 23 patients with presumed tuberculous uveitis. All patients had a positive tuberculin purified protein derivative skin test. The diagnosis was based on history, positive skin test, and physical examination. We excluded other conditions that could induce uveitis, based on the absence of signs, symptoms, or laboratory results suggesting any other diagnosis. Tuberculous uveitis was also considered in the differential diagnosis when progressive ocular inflammation was resistant to corticosteroid therapy. The patients received the following treatment: (1) isoniazid (300mg/day) and rifampin (600mg/day) for nine to 12 months, (2) ethambutol (1200mg/day) in some cases for two to three months, and (3) corticosteroids orally where indicated. In cases with anterior uveitis, we added local instillation of mydriatics and corticosteroids. There was no regression, nor were there any side effects of antituberculosis therapy in all 23 patients. We noted clinical improvement in 78% of cases. Five patients had other conditions (cataract or retinal detachment) that worsened their vision.