Stefano Sebastiani

Neurotrophic keratitis: current challenges and future prospects

Neurotrophic keratitis (NK) is a degenerative corneal disease caused by damage of trigeminal corneal innervation, which leads to spontaneous epithelial breakdown and corneal ulceration. The impairment of corneal sensory innervation causes the reduction of both protective reflexes and trophic neuromodulators that are essential for the vitality, metabolism, and wound healing of ocular surface tissues. A wide range of ocular and systemic conditions, including herpetic keratitis, ocular chemical burns, corneal surgery, diabetes, multiple sclerosis, and neurosurgical procedures, can cause NK by damaging trigeminal innervation. Diagnosis of NK requires careful investigation of any ocular and systemic condition associated with the disease, complete ocular surface examination, and quantitative measurement of corneal sensitivity. The clinical stages of NK range from corneal epithelial alterations (stage 1) to persistent epithelial defect (stage 2) and ulcer (stage 3), which may progress to corneal perforation. Management of NK is based on clinical severity, and the aim of the therapy is to halt the progression of corneal damage and promote epithelial healing. Although several medical and surgical treatments have been proposed, no therapies are currently available to restore corneal sensitivity, and thus, NK remains difficult and challenging to treat. The purpose of this review is to summarize available evidence on the pathogenesis, diagnosis, and treatment of NK. Novel medical and surgical therapies including the topical administration of nerve growth factor and corneal neurotization are also described.

Ultrasound Cyclo-Plasty in Patients with Glaucoma: 1-Year Results from a Multicentre Prospective Study

Purpose: The aim of this study was to evaluate the safety and efficacy of ultrasound cyclo-plasty (UCP) for reducing intraocular pressure (IOP) in patients with glaucoma. Methods: This is a multicentre prospective study conducted in 3 Italian glaucoma centres. UCP was performed by EyeOP1, which delivers ultrasound beams using 6 piezoelectric transducers activated for 4/6 s (first generation) or 8 s (second generation). Primary outcomes were the mean IOP reduction and the rates of success after 1 year. Secondary outcomes were the mean IOP reduction at each follow-up, and the reduction of the number of hypotensive medications. Results: In total, 49 eyes from 47 patients were treated. One year postoperatively, the mean IOP had decreased from 27.7 ± 9.2 to 19.8 ± 6.9 mm Hg (p < 0.001), and the mean number of hypotensive drops and tablets had decreased from 3.2 and 0.5 to 2.3 and 0.2, respectively (p < 0.05). Postoperative IOP reduction was significantly related to preoperative IOP (r2 = 0.5034; p < 0.0001). Second-generation probes determined a significantly higher IOP reduction (p < 0.05). Qualified success was achieved in 25 eyes (51.1%) and complete success in 21 (42.9%), while failure was recorded in 12 (24.5%). Conclusions: UCP is safe and effective for reducing IOP. The procedure determines a greater IOP reduction in patients with higher preoperative IOP. Second-generation probes improve outcomes without detrimental effects on safety.

Dry eye disease in strabismus patients: Does eye deviation harm ocular surface?

INTRODUCTION Dry eye disease is a multifactorial disease which affects the ocular surface system, and determines ocular discomfort symptoms and visual disturbance. Various types of ocular surgery, including strabismus one, represents a recognized cause for iatrogenic dry eye. However, it is not uncommon that strabismus patients, even not undergone to surgery, report symptoms of ocular discomfort and dryness. Hypothesis We hypothesize that two possible mechanisms may determine dry eye in strabismus patients by setting up a specific vicious circle: firstly, the increased exposure of the area of the bulbar conjunctiva located on the opposite side compared to the deviation may cause the thinning of the tear film lipid layer, with increased tear film instability; secondly, the dysfunctional lubricity secondary to the altered relationship between the eyelids and the deviated globe may cause blinking-related microtrauma, and thus inflammation and tear hyperosmolarity. These two entry points into the vicious circle of dry eye may determine a cascade of detrimental mechanisms, leading to further damage of the tear film, thus closing the disease circle. DISCUSSION Strabismus patients may be affected by signs and symptoms of dry eye syndrome. The increased exposure of the bulbar conjunctival area along with the dysfunctional lubricity between the eyelids and the deviated eye could be the main underlying pathophysiological mechanisms acting as entry points into the vicious circle of dry eye disease. If our hypothesis was to be confirmed, ocular surface parameters should be routinely investigated in strabismus patients, whilethe use of tear substitutes with the aim of moistening and nourishing the ocular surface could help in reducing dry eye signs and symptoms.

Ultrasound Cyclo Plasty in Eyes with Glaucoma

Glaucoma is a chronic disease caused by the progressive degeneration of the optical nerve fibers, resulting in decreased visual field that can lead to severe visual impairment, and eventually blindness. This manuscript describes a simple, surgeon-friendly, non-incisional technique, named Ultrasound Cyclo Plasty (UCP), for reducing intraocular pressure (IOP) in glaucoma patients. The technique determines a selective coagulation necrosis of the ciliary body; in addition, the stimulation of supra-choroidal and trans-scleral portions of the uveo-scleral outflow pathway has been recently proposed. UCP shows several technical improvements in ultrasound technology compared to previous techniques, providing more precise focusing on the target zone. The procedure is performed in the operating room under peribulbar anesthesia. Briefly, the coupling cone is put in contact with the eye and the ring probe, that contains six piezoelectric transducers which produce the ultrasound beams, is inserted inside it. Their proper centering over the ocular surface represents a crucial step for the correct targeting of the ciliary body. Sterile balanced salt solution is used to fill the empty spaces to ensure ultrasound acoustic propagation. Surgical treatment consists in the sequential automatic activation of each of the six transducers, for a total duration of less than 3 min. The patient leaves the hospital 1 h after the procedure with the treated eye patched. In the present study, 10 patients with open-angle glaucoma were followed-up during at least 12 months after the procedure. IOP was reduced at each interval compared to pre-operative, as well as the number of hypotensive medications. Twenty percent of patients did not respond to the treatment, and needed subsequent surgery to better control IOP. Treatment tolerability was good, with no cases of hypotony or phthisis. The UCP procedure is simpler, faster, safer, and less invasive than traditional cyclodestructive procedures with similar results in reducing IOP.

The Comparative Efficacy and Tolerability of Diclofenac 0.1% and Bromfenac 0.09% Ophthalmic Solutions after Cataract Surgery

ABSTRACT Purpose: To compare the efficacy and tolerability of diclofenac and bromfenac ophthalmic solutions as adjunctive therapy after cataract surgery. Materials and Methods: This prospective randomized controlled study included 130 patients who underwent cataract surgery. One hundred patients were randomized to receive postoperatively diclofenac 0.1% (four times daily for 28 days, Group 1) or bromfenac 0.09% (twice daily for 14 days, Group 2) ophthalmic solutions in addition to steroid-antibiotic combination. Thirty patients instilled only steroid-antibiotic combination (Control Group 3). Laser flare-cell photometry and optical coherence tomography scans with central foveal thickness (CFT) measurement were performed before (V0) and 7 (V1), 14 (V2) and 28 days (V3) after surgery. Treatment tolerability was scored using the Ocular Comfort Grading Assessment. Results: Laser flare-cell photometry values were significantly higher at V1, V2 and V3 compared to V0 in all the groups (respectively 13.3 ± 1.0, 12.7 ± 0.9 and 9.6 ± 0.9 vs 8.4 ± 0.6 ph/ms for Group 1; 13.4 ± 1.0, 12.7 ± 0.9 and 12.7 ± 1.0 vs 8.1 ± 0.6 for Group 2; 15.9 ± 0.8, 15.4 ± 0.7 and 14.5 ± 0.7 vs 7.5 ± 0.5 for Group 3) (p < 0.001); flare increase was significantly lower in Group 1 compared to Groups 2 and 3 (p < 0.001). CFT values were higher after surgery in all the three groups; the increase was significantly lower in Group 1 compared to Groups 2 and 3 (p < 0.0002). The percentage of symptoms-free patients after study treatment was significantly higher in Group 2 compared to Group 1 (respectively 74% vs 14% of the total; p < 0.001). Conclusion: The addition of diclofenac or bromfenac ophthalmic solutions contributed to further reduce both inflammation and cystoid macular edema after cataract surgery compared to steroid-antibiotic combination alone. Diclofenac appeared to be more effective in reducing postoperative intraocular inflammation with a more intense and prolonged regimen, while bromfenac more tolerated with lower daily dose and treatment duration.

Hydroxychloroquine for treatment of rheumatoid arthritis: multifocal electroretinogram and laser flare-cell photometry study

Purpose To evaluate early changes in multifocal electroretinogram (mfERG) and subclinical aqueous humor flare and cellularity in patients receiving hydroxychloroquine (HCQ) as treatment for rheumatoid arthritis. Methods Ten patients receiving treatment with HCQ and no ophthalmic symptoms were enrolled. After complete ocular examination, mfERG and laser flare-cell photometry were performed. Patients were also divided into two subgroups with HCQ cumulative dose (CD) higher or lower than 500 g. Results obtained were compared with a control group of ten healthy subjects and statistical analysis was performed. Results In patients receiving HCQ treatment, mfERG P1-wave in ring 2 showed a significant reduction in amplitude and a significant increase in latency compared to healthy control subjects, respectively resulting in 1.143 μV vs 1.316 μV (P=0.040) and 38.611 ms vs 36.334 ms (P=0.024). These changes are highly related to CD. Furthermore, when using the laser flare-cell photometry, a significant increase in aqueous humor flare and cellularity was shown in patients with CD higher than 500 g, resulting in a mean value of 14.4 ph/ms compared to 8.1 ph/ms in patients with CD lower than 500 g (P=0.0029). These reports appear highly related to CD (P=0.001). Receiver operating characteristic curve analysis showed mfERG P1-wave amplitude in ring 2 as the most sensitive value in detecting early HCQ-related retinopathy. Conclusion MfERG was shown to be a very sensitive test in detecting early retinal toxicity and should be used for the screening of patients receiving HCQ treatment. Although less sensitive, laser flare-cell photometry can provide further information to evaluate early toxic retinal cell damage.

Acute macular neuroretinopathy type 2: an unusual case

Purpose Acute Macular Neuroretinopathy (AMN) is a rare retinal disease distinguished in two different types. In type 1 the lesion occurs above the outer plexiform layer (OPL) interesting the inner nuclear layer (INL), differently in type 2 the lesion occurs below the OPL interesting the outer nuclear layer (ONL). Type 1 is more common among elderly, males, and associated with cardiovascular risk factors while type 2 is more usual in young and females. Methods A 68 years-old white man presented to Ophthalmic Emergency Room complaining the acute-onset of a paracentral superonasal scotoma in his left eye. His medical history was significant for systemic arterial hypertension in good control with diuretics and sartans. He also refers primary open angle glaucoma in treatment with prostaglandin analogous in both eyes. We performed fluorescein and indocyanine green angiographies, spectral domain-Optical Coherence Tomography (SD-OCT), OCT angiography (OCTA), standard automated perimetry (SAP), microperimetry, and multifocal electroretinogram (mfERG). Results Fluorescein and indocyanine green angiographies were unremarkable. SD-OCT revealed a focal hyperreflective band that involved the OPL and ONL localized in the parafoveal inferior region. The SAP showed a superonasal scotoma that was confirmed by the mfERG trace decrease and the inferotemporal reduced retinal sensibility at microperimetry. OCTA revealed a deep retinal capillary plexus perfusion defect area inferotemporally to the fovea. Conclusions Our case describes an unusual AMN type 2 that occurs in an elderly male patient affected by systemic arterial hypertension typical for type 1. These evidences suggest a closer pathogenic relationship between the two forms of AMN. Further studies will be able to determine whether AMN type 1 and AMN type 2 rapresent single or multiple entities.