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ZABBYS DRY AMNIOTIC MEMBRANE Z-AM-3X3 - PRICE INCLUDES PACKING AND FREIGHT

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ZABBYS DRY AMNIOTIC MEMBRANE Z-AM-3X3 (SIZE 3CM X 3CM)

ZABBYS DRY AMNIOTIC MEMBRANE Z-AM-3X3 - PRICE INCLUDES PACKING AND FREIGHT

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ZABBYS DRY AMNIOTIC MEMBRANE Z-AM-3X3  (SIZE 3CM X 3CM):

(Dry amniotic membrane)

Preserved human amnion has been successfully used as a biological bandage, promoter of epithelialisation, inhibitor of inflammation and angiogenesis, as well as a carrier for ex vivo cultured limbal stem cells. The purpose of this Histologically the amnion is a 0.02 mm to 0.5 mm five-layered membrane, composed of three basic layers.

Epithelial monolayer

The epithelium consists of a single layer of cuboidal cells with a large number of microvilli on the apical surface. The basement membrane is a thin layer composed of a network of reticular fibers. Histochemically the basement membrane closely resembles that of the conjunctiva. The compact layer contributes to the tensile strength of the membrane. The fibroblast layer is the thickest layer of the AM made up of a loose fibroblast network. The outermost layer of the amnion is the spongy layer. The basement membrane is one of the thickest membranes found in human tissue. This layer is resistant to current cryopreservation techniques. The structural integrity, transparency and elasticity of the amniotic basement membrane make it currently the most widely accepted tissue replacement for ocular surface reconstruction. It is known to promote epithelial cell migration, adhesion and differentiation. It is an ideal substrate for supporting the growth of epithelial progenitor cells by prolonging their lifespan, maintaining their clonigenicity and preventing epithelial cell apoptosis. This action explains why AMT facilitates epithelialisation for PED with stromal ulceration. In tissue cultures AM supports epithelial cells grown from explant cultures and maintains their normal morphology and differentiation. The resultant cultured epithelium can be transplanted with the AM to reconstruct damaged corneas. The AM can be used to promote non-goblet cell differentiation of the conjunctival epithelium.

Thick basement membrane

The basement membrane of the AM, cornea and conjunctiva contain collagen types IV, V and VII, in addition to fibronectin and laminin. Though the laminins are very effective in facilitating corneal epithelial cell adhesion Type V collagen helps in the epithelial cell anchorage to the stroma.

Avascular, hypocellular stromal matrix

AM produces basic fibroblast, hepatocyte and transforming growth factor (TGF). These growth factors can stimulate epithelialisation and modulate proliferation and differentiation of stromal fibroblasts. The AM stromal matrix, rich in fetal hyaluronic acid suppresses TGF B signaling, proliferation and myofibroblastic differentiation of normal corneal and limbal fibroblasts as well as normal conjunctival and pterygium fibroblasts. This action explains why AMT helps reduce scars during conjunctival surface reconstruction, prevents recurrent scarring after pterygium removal and reduces corneal haze following photorefractive keratectomy. The stromal matrix also suppresses expression of certain inflammatory cytokines that originate from the ocular surface epithelia, including interleukin 1a, IL -2, IL-8, interferon ?, tumor necrosis factor-ß, basic fibroblast growth factor and platelet derived growth factor. The AM attracts and sequesters inflammatory cells infiltrating the ocular surface and contains various forms of protease inhibitors. This may explain some of its anti-inflammatory properties.

 INDICATIONS

Conjunctival surface reconstitution

Pterygium surgery.

Chemical & burn injury

Cicatrizing conjunctivitis

Ocular Surface squamous neoplasia(OSSN)

Leaking blebs

Filtering surgery

Symblepharon release

Fornix Formation

Socket Reconstruction

Conjunctivochalasis

Corneal surface reconstruction

PEDs

Non-healing stromal ulcers

Partial LSCD

Total LSCD

Bullous keratopathy

Band keratopathy

Dry eye

SAFETY GUIDELINES

Amniotic Membrane is processed from placenta of normal & healthy mothers who undergo elective ceasarian section.

Exclusive criteria: Cases of prolonged and difficult labour and if on gross examination placenta is badly damaged, haemorrhagic or abnormal.

The donors are tested for the following :

-HIV

-VDRL

-Hepatitis B

-Hepatitis C

Informed consent is taken from every patient

Membrane is processed taking all aseptic precautions.Pieces of 3cm x 3cm are prepared and each piece is sealed in along with sterilization indicator and sent to Bhabha Atomic Research Centre (BARC) for gamma radiation.

Each lot is released only when the bio-burden report is sterile.

HOW TO APPLY

Principles of surgery

There are three basic types of AM surgery

Inlay or graft technique

When the AMG is tailored to the size of the defect and is meant to act as a scaffold for the epithelial cells, which then merges with the host tissue; it is referred to as a graft. The AM is secured with its basement membrane or epithelial side up to allow migration of the surrounding epithelial cells on the membrane.

Overlay or patch technique

When the AM is used akin to a biological contact lens in order to protect the healing surface defect beneath, it is referred to as a patch. A patch also reduces inflammation by its barrier effect against the chemical mediators from the film.

When used as patch the membrane is secured with its epithelial side up and it either falls off or is removed.

Filling-in or layered technique

In this technique the entire depth of an ulcer crater is filled with small pieces of AM trimmed to the size of the defect. A larger graft is sutured to the edges of the defect in an inlay fashion and an additional patch may help in preserving the deeper layers for a longer duration.

LIMITATIONS

One should recognize that amniotic membrane transplantation is a substrate transplantation and thus cannot be used to treat ocular surface disorders that are characterized with a total loss of limbal epithelial stem cells or conjunctival epithelial stem cells. Because amniotic membrane transplantation still relies on the host tissue to supply epithelial and mesenchymal cells, it cannot be used to reconstruct the ocular surface that has severe aqueous tear deficiency, diffuse keratinization, absence of blinking in severe neurotrophic state, and stromal ischemia. If not overcome, these conditions present as contraindication for amniotic membrane transplantation.

OUTCOME OF AMT

Cicatrizing conjunctivitis

There beneficial effects of AMT in SJS, ocular cicatricial pemphigoid and toxic epidermal necrolysis, immune- mediated inflammation must be controlled prior to surgery. There is creditable improvements in the ocular surface were measured in terms of greater patient comfort, reduced surface inflammation, decrease in the severity of vascularization and absence of recurrent corneal erosions, improvement in the ocular surface with deepening of fornices.

Chemical and thermal injury

Although AMT in eyes with acute ocular burns has advantages in terms of pain relief and rapid epithelialisation in moderate grade burns but in case of grade IV severe burns there is no definite benefit of AMT over medical therapy but is effective in promoting re-epithelialisation and reducing inflammation in the acute stage of chemical injury, thereby preventing scarring sequelae in the late stages. AMT performed during the first 7-10 days following acute burns maximizes the effects of the treatment. Associated lid deformities, symblephara and conjunctival foreshortening complicate management of chemical injury in the late stages. AMT alone gives satisfactory results in partial LSCD. In total LSCD it may be used as an adjunct to limbal stem cell transplantation.

Bullous keratopathy

Results of AMT for bullous keratopathy have been rather conflicting. Its efficacy has been studied in the palliative management of symptomatic bullous keratopathy with poor visual potential. AMT may also be performed as a temporary measure in patients waiting for corneal transplantation and intolerant to bandage contact lens (BCL). However, long-term relief from AMT needs to be studied and compared with other modalities.

Conjunctival tumours and OSSN'S

Amniotic membrane transplantation has been reported to be successful in conjunctival surface reconstruction after excision of benign as well as malignant tumors such as conjunctival melanomas, lymphomas and OSSN. When used as a graft to cover the conjunctival wound it provides a substrate for the migration of conjunctival epithelial cells. Surface lesions are particularly challenging when they arise multifocally or extend over large areas and warrant an extensive conjunctivectomy. The advantages of AMT over conjunctival autografts and mucous membrane grafts in this scenario, include superior postoperative cosmesis, absence of donor site morbidity complicatingthe harvest of mucosal and conjunctival autografts (CAG) and the ability to clinically monitor local recurrence of tumor beneath the transparent AMG. Combined therapeutic approaches consisting of extensive tumor removal, cryotherapy, topical mitomycin C and AM allograft can be effective in the management of diffuse conjunctival melanomas arising from primary acquired melanosis (PAM).

PED

PED signify varying degrees of LSCD and chronic inflammation. AM serves to provide a basement membrane substrate for the migration and adhesion of epithelial cells when used as an inlay graft. When used as an overlay patch it facilitates epithelialisation in a fashion akin to a BCL and by providing a barrier against inflammatory cells and mediators. The AM, being continuously moistened by tears, provides adequate hydration to the regenerating epithelium and protects it from the abrasive effect of an abnormal palpebral conjunctiva. Amniotic membrane transplantation may be considered an alternative method for treating PEDs that are refractory to conventional treatment such as lubrication, elimination of toxic drugs, BCL and punctal occlusion. Although results have been promising in the epithelialisation of PEDs from various causes, early detachment of the patch remains problem despite the use of multiple sutures or a protective BCL.

Pterygium surgery

Pterygium excision with a CAG has gained worldwide acceptance as the most favorable technique as it has proven to be both safe and effective in reducing pterygium recurrence.AM could serve as a useful alternative to conjunctival grafts when there exists a very large conjunctival defect to cover in primary double-headed pterygium, in previous multiple failed surgeries or in the context of preserving superior bulbar conjunctiva for future glaucoma surgeries.

Shield ulcers of vernal keratoconjunctivitis

Severe shield ulcers that do not respond to surgical debridement and BCL may be eradicated with superficial keratectomy or excimer photo therapeutic keratectomy (PTK). Amniotic membrane transplantation combined with surgical debridement is very effective alternative modality in the management of these ulcers. The renewed basement membrane promotes epithelialisation, reinforces cellular adhesion and prevents epithelial apoptosis. The surgical procedure involves complete debridement of the mucous plaque and cellular debris from the ulcer base and edge. The surrounding loose epithelium is gently peeled off until normal adherent epithelium is reached. The AMG is tailored to be a millimeter larger than the defect and sutured with 10-0 nylon interrupted sutures.

Ulcerative keratitis

Although performed in an uncontrolled and non-randomized series of patients, studies indicate that AMT shows promise in selected cases for the restoration of the ocular surface and reduction of stromal inflammation in ulcerative keratitis. Amniotic membrane transplantation can be considered an effective alternative for treating persistent neurotrophic ulcers, non-traumatic corneal perforations and descemetoceles. It can serve as a permanent therapy or as a temporizing measure until the inflammation has subsided and a definitive reconstructive procedure can be performed. Being a relatively simple procedure without risks of allograft rejection it could be particularly useful when faced with shortage of donor corneas. The stromal defect was filled up with multiple layers of AM in deep corneal ulcers which Is better than monolayer procedure..Fibrin glue in association with AMT can manage perforations of up to 3 mm in diameter.

Lid and orbital surgery

There are limited reports on the application of AMT in oculoplastic procedures. It has also been applied as a punctal patch for punctal occlusion in the treatment of dry eyes. Amniotic membrane has been used as a cover for orbital prostheses and successfully used for the closure of a conjunctival defect following hydroxyapatite orbital implant exposure. Due to its beneficial effect in facilitating rapid epithelialisation it appears to be a promising substitute to conventional grafts like mucous membrane grafts. Postoperative management A broad-spectrum topical antibiotic is used for one to two weeks initially, until the epithelium heals. Topical steroids are used for six to eight weeks in tapering doses to reduce surface inflammation. Systemic immunosuppression is not required.

ADVANTAGES OF DRY Vs WET AMNIOTIC MEMBRANE

 Can be sorted at room temperature

 No need for cold chain

 The product is gamma sterilized,so the sterility is assured

 Long shelf life of three years

 Can be cut in differnt sizeand shape so as to conform to the lesion

CONCLUSION

The success of AMT is dependent on the underlying condition and given the sub-optimal results in some indications, stringent case selection is recommended. The spectrum of clinical indications continues to expand and encompass a varying range of ocular surface pathology.

It is now evident that AMT has certainly gained an acceptable position in the surgical armamentarium of the ocular surface surgeon. The relative ease of the procedure, repeatability and freedom from intraocular intervention makes it an attractive surgical option. The low rate of intra-operative and postoperative complications and the avoidance of immunosuppression are other advantageous features of this procedure.

The future of AMT looks promising and seems like it is here to stay in the management of ocular surface disorders. With continued technological advancements in tissue processing, newer preserved forms such as the low-heat dehydrated AM are being made commercially available. Suture-less applications with fibrin glue have been aimed at making the procedure easier and more comfortable for the patient.

Further non-surgical innovations such as AMX and Prokera have made access to amnion easier than ever before. AMX is a topical application of AM extracts, currently available for use in Europe. Tseng et al have devised Prokera, which comprises AM attached to a soft contact lens-sized conformer for easy insertion. The utility of AM in healing ocular surface defects is unquestionable.

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