MACHO 17

Eye Department KCMC Newsletter

Issue 3 Volume 5 Serial 17                                                                     30 September 2015

Allergic Conjunctivitis

Allergic Conjunctivitis is an inflammatory reaction of the conjunctiva to environmental allergens causing itchy sensation in the eyes, redness and tearing. Eye rubbing makes the condition worse rather than make it better. After each session of eye rubbing, the eye itch even more eliciting a more intense rubbing.

Allergic Conjunctivitis is the most common eye disease encountered among children, there is no gender predilection. The type of Allergic Conjunctivitis that is encountered here in North-eastern Tanzania is known as Vernal Keratoconjunctivits.

Table: Number of Allergic Conjunctivitis Cases at Eye Department KCMC

	2010	2011	2012	2013	2014
Cases	2794	2974	3481	4248	4787
Rank	Nr 5	Nr 5	Nr 3	Nr 3	Nr 1
Percentage of Total	12.5%	12%	14%	17%	18%

All allergic reactions are generically termed as Hypersensitivity Reactions, of which there are of four kinds. Allergic Conjunctivitis is Hypersensitivity Type I (Anaphylaxis) and IV (Cell Mediated Reaction). These patients mount an exaggerated immune response to substances that for the rest of the population there is no reaction. Some of the allergens involved include house dust (Excrement of arthropods who feed on desquamated human skin on furniture). Patients with Allergic Conjunctivitis tend to have also Allergic Rhinitis. Mast Cells in conjunctiva degranulate Histamine which causes the inflammation and eye itch.

A patient with Allergic Conjunctivitis would report Itchy Eyes, Red Eyes, Tearing, Photophobia and Eye Discharge. The symptoms may be periodic or continuous.

Upon examination, clinician would note the following:

1. Inflamed Conjunctiva.

2. Excessive Tearing.

3. Nodular elevations of the Conjunctiva lining the inner surface of the upper eyelid known as Tarsal Papillae.

4. Pigmentation of the Conjunctiva in chronic cases.

5. Nodular elevations on the Limbus peaked with white granular deposits known as Trantas Dots.

6. Punctate Keratitis.

7. Cornea Shield Ulcer in severe cases.

Allergic Conjunctivits and its severe form Vernal Keratoconjunctivits if left untreated will lead to the following possible complications:

1. Keratoconus.

2. Cornea Scarring from Shield Ulcer.

3. Surface Cornea Vascularization known as Pannus.

Treatment options available for Allergic Conjunctivits are as follows:

1. Cold water compresses on the closed eyelids.

2. In mild forms of Allergic Conjunctivitis, vasoconstriction drugs such as Naphazoline 0.1% and Olopatadine 0.1% Eye Drops can be used as needed.

3. Antihistamine Eye Drops such as Emedastine 0.05% given three times a day in case of Seasonal Allergic Conjunctivits in adults.

4. Topical Corticosteroid Eye Drops such as Prednisolone 1% or Dexamethasone 0.1% in cases of severe symptoms. Remember that although Corticosteroids give almost instantaneous results they also put the eye at risk of Cataract, Glaucoma and Infections.  

5. Mast Cell Stabilizers such as Sodium Cromoglycate 2% and Lodoxamide 0.1% Eye Drops given four times a day are ideal drugs because of their limited side effects on long term use. They act slowly and takes up to five days for the patient to feel the difference, by this time some patients have already abandoned the use of the drugs.

6. In severe cases, sub-conjunctiva injections of Triancinolone can be used, given once every three months.

7. Topical Cyclosporine 2% Eye Drops given three times a day or topical Tacrolimus 0.1% applied once per day can be used in severe cases. 

 Trantas Dots                                                    

Giant Papillae on Tarsal Conjunctiva

Editor: W. Makupa, Eye Department KCMC, P.O.Box 3010 Moshi – Tanzania

Tel: +255 784 332 667 Fax: +255 27 275 4381 Email: makupauw@yahoo.com

PARS PLANA VITRECTOMY IN RESOURCE LIMITED COUNTRIES

Introduction

Retina Detachment Surgery and other surgeries of the vitreous body require an invasive procedure known as Pars Plana Vitrectomy. This involves accessing the vitreous body in the eye through small openings on the Sclera and inserting a Vitrectomy Probe, Light Source, Infusion Line and some other instruments as required by the procedure in question. For this surgery to be performed one would need an Operating Microscope with special adaptor for lenses that will allow for intra-ocular viewing, A Vitrectomy Machine that will have several components integrated and a Laser Machine. Most Ophthalmology Centres will have an operating microscope for which posterior segment viewing adaptors can be attached or contact vitrectomy lenses. The problem tends to be the expensive Vitrectomy / Phacoemulsification Machine that will include a Light Source, Laser Aperture, Air Injector, Oil Injector, Oil Extractor and Diathermy. These Combo machines retail in excess of $ 50,000 and most require consumables for each procedure. 

Question

Is it possible to perform Pars Plana Vitrectomy cheaply and safely in resource limited environment? This is the question that I always had. Can Retina Detachment Surgery be done a low prices and safely? In trying to answer this question I had a look at the following options.

Appasamy Avit-1 Vitrectomy Machine 

Geuder Xenotron III Light Source

Appasamy Acura-1 Air Injector

Aurolab Aurocautery

Iridex 810nm Diode Laser

Khosla AAV5 Air Pressure Driven Vitrectomy Machine

Geuder G-31890 Silicone Oil Injector

Geuder G-28752 Silicone Oil Injector Extractor

Indo-German IG-6250 Silicone Oil Injector

Answer

The total cost of these equipment is about $ 30,050/= without considering freight and customs charges. Each will require disposable consumables for each patient (Vitrectomy Probe $ 150, Light Pipe $ 150, Laser Probe $ 200, Air Tubing $ 10, Diathermy Cables $ 100 and Silicone Oil $ 200) totalling some $ 810. But as the capital equipment investment is not very large, the need to recover the principal will be reduced, therefore it will keep the cost of surgery per patient relatively low, an important factor in resource limited countries such as Tanzania. Oil injection and oil extraction can be done with manual screw type devices using 10ml syringes available from Geuder (G-31890 or G-28752) or Indo-German (IG-6250). 

MACHO 21

Eye Department KCMC Newsletter

Issue 3 Volume 6 Serial 21                                                                     30 September 2016

OUTCOME OF DIABETIC RETINOPATHY SCREENING AT MT MERU HOSPITAL IN 2015

Introduction

As a prelude to developing a comprehensive diabetic program for Arusha Region, to replicate the successes of the Kilimanjaro Diabetic Program (2010 – 2014), the Eye Department KCMC commenced diabetic retinopathy screening at Mt Meru Regional Hospital in Arusha. This screening activity is conducted at the diabetic clinic, whereby all diabetic patients are offered to be screened for retinopathy. The fundus photographs are graded at KCMC and telephonic short text messaging feedback is given to the patients on whether they need to come to KCMC for further evaluation or treatment of they should be screened again in 12 months time.

Methodology

Eye Department KCMC Diabetic Retinopathy Screening Program, the successor of Kilimanjaro Diabetic Program provided registers to record all diabetic patients attending diabetic clinic at Mount Meru Regional Hospital in Arusha. Besides the registers, patients data cards and information booklets were also provided. The patient data cards offer a quick referencing method of the database. The patient information booklet provides health education to the patient and records important biological data. Each registered diabetic patient is given an appointment to come for fundus photography. Together with fundus photography, biological parameters such as age, weight, random glycemia and blood pressure are recorded. The photographs saved in a computer and ophthalmology resident grades them on whether they have No Diabetic Renopathy (R0), Background Diabetic Retinopathy (R1), Pre-proliferative Diabetic Renopathy (R2) and Proliferative Diabetic Retinopathy (R3). Maculopathy is graded on whether there is No Maculopathy (M0), Non-referable Maculopathy (MNR) or Clinically Significant Diabetic Macula Edema (M1).

Results

In 2015, some 164 patients were photographed between 22 May 2015 and 31 December 2015. There were some 43 men and 121 women. Some 27 patients out of 163 were referred to KCMC for further examination or treatment. Some five patients out of 164 were graded as proliferative diabetic retinopathy, forming some 3% of all the screened patients. Of these five patients, two were affected bilaterally. Some 28 patients had clinically significant diabetic macula edema, forming some 17% of the 164 patients. Thirteen of them (46% of the 28) had this condition in both eyes.

Discussion

In eight months of 2015, on average some 20.5 patients were screened every month. The prevalence of proliferation is similar to the 4300 patients of the Kilimanjaro Diabetic Program, at 3%. This is important for it puts the magnitude of the problem into perspective and allows for proper planning of ophthalmic medical services. The prevalence of clinically significant diabetic macula edema was 17% (Some 28 patients out of 164). Some 46% of the 28 patients with clinically significant diabetic macula edema were affected bilaterally. The absolute number of patients needing some kind of laser therapy is 30 (18.3%) representing 48 eyes. This scant information is going to be very useful in planning large scale population screening for diabetic retinopathy screening and estimating the resources needed.

Dismas Silonga the Medical Photographer taking a Fundus Photograph.

Editor: W. Makupa, Eye Department KCMC, P.O.Box 3010 Moshi – Tanzania

Tel: +255 784 332 667 or +255 27 275 4890 Email: makupauw@yahoo.com

MACHO 20

Eye Department KCMC Newsletter

Issue 2 Volume 6 Serial 20                                                                             30 June 2016

DEVELOPMENT OF CORNEA SERVICES

Introduction

Cornea is the anterior most part of the eyeball; it is also the main refractive medium of the eyeball with 43 dioptres of the 58 dioptres of the eye. It has a vertical diameter of 11 millimetres and horizontal diameter of 12 millimetres. The central 3 millimetres of the cornea are known as the visual axis and has a radius of curvature of 7.8 millimetres. It has five layers, namely the Epithelium, Bowman layer, Stroma, Descemet Membrane and Endothelium. The Endothelium is the inner most layer of the cornea, it is a metabolic water pump that keeps the cornea in a relative state of dehydration and transparent. This layer does not regenerate if damaged, which can occur in case of eye surgery, eye trauma or genetical causes. Once damaged, it has to be replaced with another cornea from another person.

Problem Statement

When the Eye Department is presented with a patient whose cornea has decompensated (Metabolic water pumps is dysfunctional due to Endothelial damage), there is very little that can be done other than offer Sodium Chloride 4% eye drops and place the patient on Cornea Transplantation Waiting List. The last cornea transplantations were done in August 2011. Short of referring the patients to India there is very little else that can be done.

Cause of the Problem

There is no frame work for cornea harvesting in Tanzania, although historically there has been Penetrating Keratoplasty done at KCMC and Muhimbili dating back from the 1970s. There was a general assumption that these surgeries were on the very fringes of legality. Fundamentally momentarily there are no human cornea donors.

Solution

The Eye Department KCMC had started lobbying for Issuance of Guidelines and Regulations for Human Organ Harvesting and Transplantation in Tanzania in 2011. In the process it was realized in 14 March 2016 that there was a law already addressing the specific issue, thanks to Dr Andrew L. Quaker. This is the Penal Code (Anatomy Rules) Act 1963 No 192 10 (1) and 10 (2) which authorises the Medical Officer in Charge to consent removal of cadaveric tissue within reasonable time for purposes of treatment. The “discovery” of this law means that cornea can be sourced domestically within the law.

Parallel with this development, one of our departmental cadres had just finished a one year Cornea Sub-specialization course in Aravind India. Dr Elisante Muna has returned with optimism and drive to develop this sub-speciality at KCMC. In this view the Eye Department is now actively pursuing procurement of a Cornea Cross Linking Laser Machine, Biological Glue and framework for cornea harvesting and processing. We are looking forward to a fully fledged cornea sub-speciality service at KCMC.

Dr Elisante Muna inspecting the Cornea Cross-Linking Machine

    

Editor: W. Makupa, Eye Department KCMC, P.O.Box 3010 Moshi – Tanzania

Tel: +255 784 332 667 or +255 27 275 4890 Email: makupauw@yahoo.com

MACHO 16

Eye Department KCMC Newsletter

Issue 2 Volume 5 Serial 16                                                                               30 June 2015

Selective Laser Trabeculoplasty

Glaucoma is the leading cause world wide if irreversible blindness. This is a disease whereby the optic nerve head is damaged by raised intraocular pressure. The optic nerve is the convergence of the nerves originating from the photoreceptors of the retina in their path towards the visual cortex; their function is to deliver the visual stimulus to the brain for interpretation. In case of raised intraocular pressure, the individual axons are damaged at the level of the lamina cribrosa of the optic nerve head, as the histioarchitecture renders this spot with inherent weakness. In primary open angle glaucoma the cause for raised intraocular pressure is resistance to outflow at the trabecular meshwork.

As glaucoma progresses, the visual field of the patient is constricted or develops islands of defect, however vision remains normal. This means that the patient will be unaware that they are gradually loosing their visual function. The triad of glaucoma includes:

1. Measurement of Intraocular Pressure (Normal is 9 – 21 mmHg)

2. Evaluation of the Optic Nerve Head Excavation (Normal is less than 0.8)

3. Visual Field Test

Glaucoma treatment includes medical and surgical approaches. Most of the patients will be put on intraocular pressure lowering eye drops initially, such as Timolol 0.5%, Brimonidine 0.2%, Dorzolamide 2% or Latanoprost 0.005%. In some patients one type of eye drops or several combinations of eye drops are enough to control the disease. Disease control is assessed by annual visual field tests to evaluate progress. Sometimes intraocular pressure readings alone are an indicator enough of progress.

Trabeculectomy is the standard surgical procedure when medical treatment is not effective in controlling the intraocular pressure. This procedure constitutes creation of a fistula between that anterior chamber and the sub-tenons space. Most of the complications arising from trabeculectomies are caused either by over filtration in the first few days or failure due to the bodies inherent repair processes. Other surgical options include trabeculotomy, goniotomy for children and synthetic drainage valves such as Ahmed Valve, Molteno Valve and Express Shunt.

Diode laser is used in Cyclophotocoagulation of the ciliary body in cases of a painful blind eye or in case other surgical procedures can not be done. Argon Laser Trabeculoplasty is used to lower the intraocular pressure by causing photocoagulation of the trabecular meshwork, causing contraction of tissue and opening of channels.

Selective Laser Trabeculoplasty is a 532nm frequency double YAG laser that is applied to the trabecular meshwork, its mechanism of action is not clear, however the impact is reduction of intraocular pressure. The hypothesis is that the laser induces cell division, release of mediators of inflammation which restore the trabecular meshwork function. Some 100 spots of laser can be applied to the trabecular meshwork and the process may be repeated more than once. A special goniolens is needed to visualize and treat the trabecular meshwork in the chamber angle. The response rate to treatment varies between 58% – 94% in year one and plummets to 31% - 58% after 5 years. Given that it is administrered once or twice and may buy up to five years of slowing down glaucoma progression it is a positive development. The high cost of the laser machine remains a challenge. The Eye Department is lucky in having this important therapeutic tool that is expected to impact positively in the glaucoma management.

Dr Heiko Philippin, the Glaucoma Specialist treating a patient with the SLT

Editor: W. Makupa, Eye Department KCMC, P.O.Box 3010 Moshi – Tanzania

Tel: +255 784 332 667 Fax: +255 27 275 4381 Email: makupauw@yahoo.com