Ruben Grigorian

Diabetic Macular Edema: Pathogenesis and Treatment

Diabetic macular edema is a major cause of visual impairment. The pathogenesis of macular edema appears to be multifactorial. Laser photocoagulation is the standard of care for macular edema. However, there are cases that are not responsive to laser therapy. Several therapeutic options have been proposed for the treatment of this condition. In this review we discuss several factors and mechanisms implicated in the etiology of macular edema (vasoactive factors, biochemical pathways, anatomical abnormalities). It seems that combined pharmacologic and surgical therapy may be the best approach for the management of macular edema in diabetic patients.

Management of Traumatic Hyphema

Hyphema (blood in the anterior chamber) can occur after blunt or lacerating trauma, after intraocular surgery, spontaneously (e.g., in conditions such as rubeosis iridis, juvenile xanthogranuloma, iris melanoma, myotonic dystrophy, keratouveitis (e.g., herpes zoster), leukemia, hemophilia, von Willebrand disease, and in association with the use of substances that alter platelet or thrombin function (e.g., ethanol, aspirin, warfarin). The purpose of this review is to consider the management of hyphemas that occur after closed globe trauma. Complications of traumatic hyphema include increased intraocular pressure, peripheral anterior synechiae, optic atrophy, corneal bloodstaining, secondary hemorrhage, and accommodative impairment. The reported incidence of secondary anterior chamber hemorrhage, that is, rebleeding, in the setting of traumatic hyphema ranges from 0% to 38%. The risk of secondary hemorrhage may be higher in African-Americans than in whites. Secondary hemorrhage is generally thought to convey a worse visual prognosis, although the outcome may depend more directly on the size of the hyphema and the severity of associated ocular injuries. Some issues involved in managing a patient with hyphema are: use of various medications (e.g., cycloplegics, systemic or topical steroids, antifibrinolytic agents, analgesics, and antiglaucoma medications); the patients activity level; use of a patch and shield; outpatient vs. inpatient management; and medical vs. surgical management. Special considerations obtain in managing children, patients with hemoglobin S, and patients with hemophilia. It is important to identify and treat associated ocular injuries, which often accompany traumatic hyphema. We consider each of these management issues and refer to the pertinent literature in formulating the following recommendations. We advise routine use of topical cycloplegics and corticosteroids, systemic antifibrinolytic agents or corticosteroids, and a rigid shield. We recommend activity restriction (quiet ambulation) and interdiction of non-steroidal anti-inflammatory agents. If there is no concern regarding compliance (with medication use or activity restrictions), follow-up, or increased risk for complications (e.g., history of sickle cell disease, hemophilia), outpatient management can be offered. Indications for surgical intervention include the presence of corneal blood staining or dangerously increased intraocular pressure despite maximum tolerated medical therapy, among others.

Vitrectomy with silicone oil infusion in severe diabetic retinopathy

Aims: To determine the results of pars plana vitrectomy (PPV) and silicone oil infusion (SOI) in severe proliferative diabetic retinopathy (PDR). Methods: The records of 23 eyes (21 patients: 12 males, nine females) with PDR who had undergone PPV and SOI were reviewed retrospectively. Results: Average follow up was 5.4 months (range 1–25). Surgical indications were tractional retinal detachment (TRD) (17.4%), traction-rhegmatogenous retinal detachment (TRRD) (8.7%), TRD with vitreous haemorrhage (VH) (48%), TRD with neovascular glaucoma (NVG) (8.6%), TRD with fibrinoid syndrome (FS) (17.3%). With one operation, the retinal reattachment rate was 17/23 (74%). Among these 23 eyes, 11 (48%) had previously failed vitrectomy, and the retina was attached in 8/11 (73%) with a single procedure. With additional surgery employing PPV and SOI, the final reattachment rate was 20/23 (87%). The only cases with intraocular pressure <5 mm Hg had retinal detachment. Postoperative visual acuity (VA) improved in 10 eyes (44%), was unchanged in three (12%), and decreased in 10 eyes (44%). Conclusion: SO tamponade is useful in severely diseased eyes with PDR, even in the presence of rubeosis iridis (RI) and NVG, FS, or in cases with previously failed vitrectomy, especially in the presence of RI.

A new technique for suture fixation of posterior chamber intraocular lenses that eliminates intraocular knots

PURPOSE The aim of this study was to describe a new technique for transscleral suturing of posterior chamber intraocular lenses (PCIOLs) without intraocular knots. DESIGN Retrospective noncomparative case series. PARTICIPANTS Twenty-four eyes underwent implantation of PCIOLs with this new technique. METHODS Suture fixation of PCIOLs was performed in eyes without capsular support. MAIN OUTCOME MEASURES The anatomic and functional outcome of surgery was determined during a follow-up of 2 to 40 months. RESULTS The PCIOL remained well centered without tilt in 22 of 24 (92%) eyes. The PCIOL was well centered in 16 of 17 (94%) eyes followed for > or =6 months. Complications related to lens suturing were minimal and resolved spontaneously. Final visual outcome depended almost entirely on the underlying health of the retina and optic nerve. CONCLUSION This technique eliminates intraocular knots, minimizes operating time with an open globe, and provides excellent lens centration in the absence of capsular support.

Epiretinal membrane removal in diabetic eyes: comparison of viscodissection with conventional methods of membrane peeling

Aims: To compare conventional methods of epiretinal membrane peeling with viscodissection. Methods: 154 eyes with proliferative diabetic retinopathy (PDR) that underwent pars plana vitrectomy with membrane dissection (89 traditional, 65 viscodissection) were studied retrospectively. Incidence of retinal breaks (RBs), length of time under anaesthesia, postoperative intraocular pressure, retinal reattachment rate, and final visual acuity (VA) were measured. Results: To compare cases of similar complexity, a “complexity score” was defined. The average complexity score for cases done with and without viscodissection was 4.7 and 3.2, respectively. The mean frequency of RBs in eyes undergoing viscodissection was 0.43 (SD 0.5) v 0.14 (0.35) RBs/eye without viscodissection. In complex cases, the frequency of posterior/peripheral RBs was 0.31 (0.47)/0.13 (0.34) RBs/eye, respectively, with viscodissection v 0.12 (0.33)/0.23 (0.43) RBs/eye without viscodissection. None of these differences were statistically significant. The average preoperative/postoperative VA (logMAR) in the viscodissection cohort was 1.7/1.3 (range 0.3 to >1.9/0.1 to >1.9) v 1.4/1 (range 0.48 to >1.9/0.1 to >1.9) in the non-viscodissection cohort, among eyes with 6 months of follow up. Anaesthesia duration was significantly shorter for cases done without viscodissection (p=0.03), but cases done with viscodissection were significantly more complex than cases done without viscodissection (p<0.0001). Conclusion: Viscodissection appears to be a safe and effective alternative technique in eyes with PDR. Owing to the retrospective nature of the study, additional studies are warranted.

Neuro-ophthalmic manifestations of sarcoidosis : Clinical spectrum, evaluation, and management

Objective To familiarize the reader with the neuro-ophthalmic manifestations of sarcoidosis. Materials and Methods All patients underwent systemic evaluations (chest radiograph, magnetic resonance imaging and/or computed tomography, serum angiotensin-converting enzyme level, and gallium scan). Histologic confirmation was preferred (11 of 15 patients underwent biopsy, ten of whom [82%] had positive biopsies, and four refused). Otherwise, the diagnosis of clinical sarcoidosis was based on laboratory evaluation. Results We report our experience with 15 patients who had neuro-ophthalmic manifestations of sarcoidosis other than optic neuropathy or chiasmal disease. Eight of 15 (53%) did not have known sarcoidosis at the time of presentation. Thirteen of 15 (87%) patients demonstrated lesions consistent with sarcoidosis on magnetic resonance imaging of the brain. Treatment with corticosteroids and/or other immunomodulatory agents was necessary in all cases. Conclusions Neuro-ophthalmic manifestations of sarcoidosis are rare. They may be the presenting signs of otherwise occult disease. Suspicion and inclusion in the differential are a key to establishing the diagnosis. A strategy for the detection and evaluation of these cases is presented.

Pars plana vitrectomy for refractory diabetic macular edema.

Objective. The aim of this study is to describe the results of pars plana vitrectomy (PPV) for refractory diabetic macular edema (DME). Methods. Review of the relevant peer-reviewed scientific literature identified using Medline. Main Outcome Measures. The anatomical and functional outcome of surgery. Results. Vitrectomy with or without internal limiting membrane (ILM) peeling can be beneficial for the treatment of DME that is resistant to laser photocoagulation or sub-Tenon’s steroid injection. Visual improvement has been reported in ~40–90% of patients, with ~85–100% experiencing either improvement or stabilization of vision. Retinal edema decreases or resolves in ~70–100% of patients. Complications range in severity with ~5–20% of patients developing peripheral retinal breaks, ~1–2% developing retinal detachment, ~2% developing macular hole, and ~10–60% developing cataract. Severe complications such as rubeosis iridis and the fibrinoid syndrome have also been reported. Conclusion. Pars plana vitrectomy can be an effective treatment for diabetic macular edema refractory to laser therapy and/or sub-Tenon’s capsule steroid injection.

360° retinectomy for the treatment of complex retinal detachment.

Purpose: To review the anatomical and functional outcomes of eyes that underwent 360° retinectomy for a variety of indications and compare them with previously published results. Methods: Retrospective case series. We reviewed the data of 40 patients (41 eyes) who underwent pars plana vitrectomy and 360° retinectomy. The principal indication for surgery in this series was retinal detachment after penetrating trauma (26 of 41 eyes [63%]). Anatomical success was defined as complete retinal reattachment or attachment posterior to the scleral buckle, if present. Results: Thirty of the 41 eyes (73%) had follow-up of at least 6 months after 360° retinectomy, and of these, 11 eyes (37%) had recurrent retinal detachment. Seven of the latter eyes underwent repeat pars plana vitrectomy with anatomical success in 6 eyes (86%). Overall, anatomical success was achieved in 25 of 30 eyes (83%) with follow-up of ≥6 months after ≥1 operations (including 360° retinectomy). Visual results were limited with only 4 of 35 eyes (11%) in which visual acuity could be tested achieving ambulatory vision, which may reflect the preponderance of posttraumatic retinal detachments in this series. Conclusion: The anatomical results of this series are comparable with those in the reported literature and indicate that vitrectomy with 360° retinectomy can be beneficial in the management of complex retinal detachments in otherwise unsalvageable eyes.

Use of viscodissection and silicone oil in vitrectomy for severe diabetic retinopathy

Improvement in surgical techniques has led to improved anatomic and functional success rates following surgery for severe complications of proliferative diabetic retinopathy (PDR). We compared the anatomic and functional outcomes of surgery in a non-randomized, consecutive case series of patients with severe PDR. We found that viscodissection using Healon® provides outcomes comparable to conventional pick and scissors dissection. We also found that adjunctive use of silicone oil can salvage selected cases with particularly severe manifestations of PDR (e.g., the fibrinoid syndrome). With proper selection of patients and techniques, the anatomic success rate can exceed 80% even in the most severe cases. The goal of this paper is to show the applicability of using viscodissection and silicone oil infusion during vitrectomy in eyes with severe PDR.

Evolution of sarcoid granulomas of the retina

PURPOSE To report a case of a young woman with a history of sarcoidosis who developed retinal granulomas. METHODS Case report. RESULTS A 33-year old woman with history of sarcoidosis with involvement of the central nervous system, confirmed by skin biopsy, bronchoscopy, and neuroimaging, presented with visual loss and was found to have choroidal and optic nerve granulomas in the left eye, and subsequently developed retinal granulomas in the left eye. CONCLUSION Retinal granuloma is a rare manifestation of sarcoidosis.