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Indian Journal of Ophthalmology
The authors mention that direct instillation of the silicon elastomer into the socket followed by eye closure is beneficial as it helps in recreating the exact shape of the socket. The authors mention in the discussion “impression techniques using custom or stock trays and prefabricated acrylic shells to carry impression materials into the defect interferes with complete closure of eyelids and functional molding of the material by various ocular movements.” However one unique problem when asking the patient to close his eyes while obtaining a socket impression is the induction of Bell’s phenomenon, which is preserved even in an enucleated eye. This will compromise the impression mold created of the socket and lead to a major disadvantage of ocular prosthesis rotation. Hence, there is no advantage in obtaining an impression with eyes closed as mentioned by the authors. On the contrary, there are some definite benefits of using an impression tray.[2] While obtaining a socket impression we can ask the patient to move his/her eyes in different directions with the impression tray in situ, so that we can obtain the functional impression. A major advantage of the impression tray is the front surface contouring is much easier as opposed to the technique suggested in the article as it provides a normal globe contour. There is no chance of overfill or creation of a protruding artificial eye when an impression tray is used. The palpebral conjunctiva is always smooth and hence one has to have a smooth surface on the finished ocular prosthesis, which is possible due to the smooth contour of the impression tray. Even in cases of chemical/thermal burns the palpebral surface can be accurately recorded with the impression tray in situ. Use of an impression tray helps in defining the superior and inferior fornices and the medial and lateral canthi accurately provided we choose the correct impression tray (one that is of apt size). Prefabricated impression trays are available in various sizes intended for use for the left eye and right eye separately. The tube attached to the impression tray helps in delivering the impression material into the socket. Accurate wax modeling after using an impression tray technique can successfully prevent issues like lagophthalmos. To conclude, we wish to emphasize that use of impression tray is necessary in all cases. This helps in accurate wax modeling, which is of prime importance in achieving optimal sizing and a comfortable fit of the ocular prosthesis.
Respond to: An innovative impression technique for fabrication of a custom‑made ocular prosthesis Dear Sir, Thank you very much for your interest and questions regarding our article. We are very glad to answer your questions. We can consider using custom fabricated tray but not the prefabricated trays as alternative to direct impression technique. The following quires we received during our article review and the explanations by us will clarify your questions. 1. What are the technical difficulties should be mentioned; how to remove the mold which has set if it is without handle or tray?
Vol. 63 No. 10
Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.
Ramesh Murthy, Madhulata Umesh Oculoplasty, Ocularistry and Squint Service, Axis Eye Clinic, Pune, Maharashtra, India Correspondence to: Dr. Ramesh Murthy, Axis Eye Clinic, No. 20, Prashant Society, Paud Road, Pune ‑ 411 038, Maharashtra, India. E‑mail:
[email protected]
References 1. Tripuraneni SC, Vadapalli SB, Ravikiran P, Nirupama N. An innovative impression technique for fabrication of a custom made ocular prosthesis. Indian J Ophthalmol 2015;63:545‑7. 2. Allen L, Webster HE. Modified impression method of artificial eye fitting. Am J Ophthalmol 1969;67:189‑218.
This is an open access article distributed under the terms of the Creative Commons Attribution‑NonCommercial‑ShareAlike 3.0 License, which allows others to remix, tweak, and build upon the work non‑commercially, as long as the author is credited and the new creations are licensed under the identical terms. Access this article online Quick Response Code:
Website: www.ijo.in DOI: 10.4103/0301-4738.171536 PMID: ***
Cite this article as: Murthy R, Umesh M. Fabricating a custom made ocular prosthesis. Indian J Ophthalmol 2015;63:807-8.
Response: Handle of the custom tray mainly aids in carrying the impression material and the tray into the defect and to stabilize the tray while molding the impression.[1‑3] The role of the handle while removing the set impression is limited. The set impression was removed from the defect by applying slight oblique outward pressure near inferior palpebral fissure or holding the material flash on the outer surface of the impression with tweezers.[1] Conditions that demands use of special tray with handle are obliterated defect size and shallow palpebral fissures which hold very less amount of impression material if it is injected directly. Prostheses fabricated in these conditions by using the custom tray, and the handle is oversized than the defect. The best treatment option in these scenarios is a surgical correction of the defect to get appropriate palpebral fissure depth for the comfortable prosthesis.[1‑3]
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Letters to the Editor
2. How much is the difference in ocular motility attained using this method as compared to stock tray method? Response: Lack of custom tray and handle in direct impression technique provides complete closure of the eyelids while molding the impression which facilitates accurate recording of palpebral contours of the defect along with tissue surface. This also facilitates accurate recording of ocular musculature effect on prosthesis contours in function without interference.[1,4,5] Recording of the palpebral contours of the defect decreases the time required to carve the palpebral surface of the wax pattern when compared with the wax pattern fabricated by impression using the custom tray and handle. The intimate contact between prosthesis and inner surface of the eyelids considerably helps in free movement of the prosthesis coordinated with ocular movements than prosthesis fabricated from the wax pattern with hand carved palpebral surface. Financial support and sponsorship Nil. Conflict of interest There are no conflicts of interest.
Sunilchandra Tripuraneni, Sriharsha Babu Vadapalli, Kaleswararao Atluri, Ravikiran Potluri1 Department of Prosthodontics and Maxillofacial Prosthetics, Dr. Sudha and Nageswara Rao Siddhartha Institute of Dental Sciences, 1 Pinnamaneni Siddhartha Institute of Medical Sciences, Gannavaram, Krishna, Andhra Pradesh, India Correspondence to: Dr. Sunilchandra Tripuraneni, Department of Prosthodontics and Maxillofacial Prosthetics, Dr. Sudha and Nageswara Rao Siddhartha Institute of Dental Sciences, Gannavaram, Krishna, Andhra Pradesh, India. E‑mail:
[email protected]
Raynaud’s phenomena and subclavian steal syndrome: Differential diagnosis for retinal artery occlusion Dear Sir, We read with interest the article titled, “Cilioretinal artery occlusion following intranasal cocaine insufflation” by Kannan et al.[1] We appreciate the authors’ research work. We would like to highlight few points regarding Raynaud’s phenomena which are a differential diagnosis for vaso‑occlusive disorder. Raynaud’s phenomena [2] are characterized by exaggerated vasoconstrictive color changes (pallor and cyanosis) in the fingers, usually due to exposure to cold. Primary Raynaud’s phenomena (PRP) are not associated with underlying systemic disease. Secondary Raynaud’s is associated with systemic lupus erythematosus, scleroderma, and peripheral vascular disease.[2] Stress is a risk factor for Raynaud’s phenomena.[3] PRP may be a manifestation of diffuse vasospastic disorder affecting cerebral, coronary, mesenteric vessels. PRP patients have higher incidence of chest pain, migraine, and stroke. Evidence suggest that abnormalities in smooth muscle and endothelium of blood vessels, central sympathetic control of vascular tone, and
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References 1. Tripuraneni SC, Vadapalli SB, Ravikiran P, Nirupama N. An innovative impression technique for fabrication of a custom made ocular prosthesis. Indian J Ophthalmol 2015;63:545‑7. 2. Mathews MF, Smith RM, Sutton AJ, Hudson R. The ocular impression: A review of the literature and presentation of an alternate technique. J Prosthodont 2000;9:210‑6. 3. Allen L, Webster HE. Modified impression method of artificial eye fitting. Am J Ophthalmol 1969;67:189‑218. 4. Parr GR, Goldman BM, Rahn AO. Surgical considerations in the prosthetic treatment of ocular and orbital defects. J Prosthet Dent 1983;49:379‑85. 5. Krastinova D, Kelly MB, Mihaylova M. Surgical management of the anophthalmic orbit, part 1: Congenital. Plast Reconstr Surg 2001;108:817‑26.
This is an open access article distributed under the terms of the Creative Commons Attribution‑NonCommercial‑ShareAlike 3.0 License, which allows others to remix, tweak, and build upon the work non‑commercially, as long as the author is credited and the new creations are licensed under the identical terms. Access this article online Quick Response Code:
Website: www.ijo.in DOI: 10.4103/0301-4738.171537 PMID: ***
Cite this article as: Tripuraneni S, Vadapalli SB, Atluri K, Potluri R. Respond to: An innovative impression technique for fabrication of a custom-made ocular prosthesis. Indian J Ophthalmol 2015;63:808-9.
circulating mediators may all be involved in its pathogenesis. Calcium channel blockers, topical nitroglycerine (fingers), and sildenafil may play a part in management of Raynaud’s phenomena.[3] Ophthalmic artery vasospasm due to subclavian steal syndrome may clinically present as incomplete central retinal artery and short posterior ciliary artery occlusion.[4] To conclude, Raynaud’s phenomena and subclavian steal syndrome should be considered in differential diagnosis of ocular arterial occlusion disease. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.
Natarajapillai Venugopal Department of Neuro‑ophthalmology, Clinic and Glaucoma Service, AG Eye Hospital, Tiruchirappalli, Tamil Nadu, India Correspondence to: Dr. Natarajapillai Venugopal, No. 19, Mathuram Apartments (Behind YMCA), Officer’s Colony, Puthur, Tiruchirappalli ‑ 620 017, Tamil Nadu, India. E‑mail:
[email protected]
