An Implantable Device Design Concept for Ocular Drug Delivery

Author(s):  
Jae-Hwan Lee ◽  
Ramana M. Pidaparti

New drugs for curing eye diseases have been developing for a decade and are very unique for each eye diseases such as glaucoma, cataracts, and age-related macular degeneration (AMD). It is estimated that 1.6 million adults in the US over the age of 50 and above suffer from age-related macular degeneration and about 200,000 cases are diagnosed annually. Worldwide, about 500,000 cases are diagnosed annually [1]. Drugs currently utilized for AMD are delivered via repeated intravitreal injections of the drug into the eye. Risks of repeated intravitreal injections can include intraocular infections (endophthalmitis), intraocular hemorrhage, and retinal detachment. Also, reducing the frequency of dosing will clearly benefit the patient by reducing the need for risky intravitreal injections and improving the pharmacokinetics of the drug in the eye. The eye disease of posterior segment (Dry and Wet) has limits to deliver the drug to retina region using typical eye drop. The drug injection using a needle with syringe can deliver but it barely provide right amount of doses, or over doses that may cause more severe problem such as swelling, fatigue, and damaging photoreceptor molecules. Furthermore, most drugs run away in a month so that repeated injection is necessary. Developing an implantable drug delivery device will help reduce the costs and risks associated with frequent injections and facilitate delivering the drug in a controlled manner and in the required amounts, and improve therapeutic efficacy and safety of drugs. This study focuses on the design, simulation and development of the implantable ocular drug delivery device.

2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
Jae-Hwan Lee ◽  
Ramana M. Pidaparti ◽  
Gary M. Atkinson ◽  
Ramana S. Moorthy

Ocular diseases, such as, glaucoma, age-related macular degeneration (AMD), diabetic retinopathy, and retinitis pigmentosa require drug management in order to prevent blindness and affecting million of adults in USA and worldwide. There is an increasing need to develop devices for drug delivery to address ocular diseases. This study focuses on the design, simulation, and development of an implantable ocular drug delivery device consisting of micro-/nanochannels embedded between top and bottom covers with a drug reservoir made from polydimethylsiloxane (PDMS) which is silicon-based organic and biodegradable polymer. Several simulations were carried out with six different micro-channel configurations in order to see the feasibility for ocular drug delivery applications. Based on the results obtained, channel design of osmotic I and osmotic II satisfied the diffusion rates required for ocular drug delivery. Finally, a prototype illustrating the three components of the drug delivery design is presented. In the future, the device will be tested for its functionality and diffusion characteristics.


2021 ◽  
pp. 48-56
Author(s):  
Atsuta Ozaki ◽  
Hisashi Matsubara ◽  
Masahiko Sugimoto ◽  
Manami Kuze ◽  
Mineo Kondo ◽  
...  

Intravitreal injection of anti-vascular endothelial growth factor (anti-VEGF) is essential for the treatment of macular diseases such as wet age-related macular degeneration and macular edema. Although continued treatment is needed to maintain good vision, some patients cannot continue such injections for various reasons, including specific phobias. Here, we report a case of a patient with a specific phobia of intravitreal injections who could resume treatment after undergoing combined drug and cognitive-behavioral therapy (CBT). A 74-year-old Japanese man diagnosed with retinal angiomatous proliferation by fluorescein angiography and indocyanine green angiography was treated with intravitreal anti-VEGF injection. However, at 8 months after the first treatment, he became difficult to treat because of a phobia of injections. He was treated with photodynamic therapy, but his macular edema did not improve. After a psychiatric consultation, he was diagnosed with a specific phobia of intravitreal injections. Combined drug and CBT enabled him to resume receiving intravitreal injections. This case demonstrates that a specific phobia of intravitreal injections may benefit from combined drug and CBT. In this regard, some patients with high anxiety and fear of intravitreal injections should be referred to a psychiatrist at an early stage.


QJM ◽  
2020 ◽  
Vol 113 (Supplement_1) ◽  
Author(s):  
M S Abdaltawab ◽  
Z F Ismail ◽  
W M A Ebeid ◽  
S M Fawzy

Abstract Aim of the Work The aim of this work is to compare the response of treatment with ranibizumab in terms of visual acuity in cases of CNV secondary to pathological myopia versus CNV secondary to age-related macular degeneration. Methods This prospective, comparative study included ten eyes newly diagnosed as having CNV secondary to pathological myopia, and 10 eyes newly diagnosed as having subfoveal active CNV secondary to AMD. All patients had 3 monthly intravitreal Injections of 0.50 mg (in 0.05 ml of solution) ranibizumab with monthly evaluation of best corrected visual acuity (BCVA) by Landolt C chart, and also calculated in Logarithm of Minimum Angle of Resolution (Log MAR). Results pretreatment there was no significant difference between the two groups as the mean VA (Log Mar) was 1.31 ± 0.2 in AMD group and 1.17 ± 0.3 in MCNV group of P value = 0.431 and also post three IVI of ranibizumab showed no significant difference between the two groups as the mean VA (Log Mar) was 1.22 ± 0.2 for AMD and 1.22 ± 0.5 for MCNV of P value = 0.635. Conclusion there was no significant difference in BCVA between AMD and MCNV groups after three intravitreal injections of ranibizumab.


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