{"id":6438,"date":"2022-04-09T14:20:00","date_gmt":"2022-04-09T12:20:00","guid":{"rendered":"https:\/\/ver-ooginoog.nl\/bibliotheek\/update-on-research-into-anophthalmia-and-microphthalmia\/"},"modified":"2026-09-15T15:57:42","modified_gmt":"2026-09-15T13:57:42","slug":"update-on-research-into-anophthalmia-and-microphthalmia","status":"publish","type":"library_pt","link":"https:\/\/ver-ooginoog.nl\/en\/library\/anophthalmia-and-microphthalmia\/update-on-research-into-anophthalmia-and-microphthalmia\/","title":{"rendered":"Update on Research into Anophthalmia and Microphthalmia"},"content":{"rendered":"<div class=\"wp-block-post-date\"><time datetime=\"2022-04-09T14:20:00+02:00\">09 April 2022<\/time><\/div>\n<p class=\"wp-block-paragraph\"><strong><em>By Annabel Groot, ophthalmologist<\/em><\/strong><\/p>\n<p>The first chapter discusses how eye size develops normally. This is measured from the front (the cornea) to the back of the eye and is called the \u201caxial length.\u201d To this end, a comprehensive search of the medical literature was conducted in medical databases. Data from no fewer than 6,500 eyes were extracted from 27 articles published between 1964 and 2018. These were compiled and summarized into a clear growth curve, which shows how eye size increases each week of development. The curve also includes data on eye size development while the baby is still in the womb, so that even in premature babies, it is possible to determine whether the eye size is abnormal.       <\/p>\n<h2 class=\"wp-block-heading\">Curved, Growing Eye<\/h2>\n<p class=\"wp-block-paragraph\">The first data are available around 12 weeks after conception: at that point, the eye is on average 5 mm long. In the weeks that follow, growth accelerates rapidly: by 21 weeks, the eye is already well over 10.4 mm, and by 30 weeks, it measures 15 mm. So, in those 18 weeks, an eye grows about one centimeter! But after that, growth slows down quickly: at birth (on average around 40 weeks), the eye is about 16.8 mm long, so growth isn\u2019t nearly as impressive during the final 10 weeks. By the time a child is 3 years old, the eye is already nearly 22 mm in size. That is already 93% of the eventual average adult eye length, which ultimately grows to about 23.6 mm (Source: Klaver et al. 2018).       <\/p>\n<h2 class=\"wp-block-heading\">Treatment depends on the condition of the healthy eye<\/h2>\n<p class=\"wp-block-paragraph\">In the second chapter, data from 58 children who regularly attended the MICA clinic are analyzed\u2014anonymously, of course, and only after their parents gave their consent. An ophthalmologist, orthoptist, ocularist, radiologist, and clinical geneticist all collected data, ranging from DNA analysis and imaging to information on visual acuity, eye size, and eyelid length. The most important finding was that the rationale for treatment in cases of unilateral anophthalmia or microphthalmia depends on the ratio to the healthy eye. If the affected eye was smaller than 45% of the healthy eye, the asymmetry was such that treatment with conformers was often initiated immediately. This constitutes the \u201csevere\u201d category. If the size was between 45% and 75% (the \u201cmoderate\u201d category), there was no immediate urgency, but the decision to proceed with treatment depended, for example, on the extent of remaining vision in the eye, whether the cornea was still sensitive, and the parents\u2019 preference. If the eye size was more than 75% (the \u201cmild\u201d category), the asymmetry was not so bothersome that it was also an option to simply wait and see. In cases of bilateral involvement, the rationale for treatment is somewhat more complex and depends on several factors: it is always necessary to assess whether and to what extent vision is present, as that is the most important consideration. In cases of clear asymmetry, if one side is definitely unable to see, treatment with conformers or prostheses is an option, but this is evaluated on a case-by-case basis for each child. It was also noted that some of the eyes stop growing entirely, while others with microphthalmia continue to grow. If growth stagnates, the degree of asymmetry may increase over time.            <\/p>\n<h2 class=\"wp-block-heading\">Genetic causative mutations<\/h2>\n<p class=\"wp-block-paragraph\">Other significant findings included that a genetic mutation was identified in 25% of cases, and that half of the children also had other physical abnormalities, such as in the brain, heart, or kidneys. In the group with severe bilateral microphthalmia, there was a high likelihood of an explanatory gene mutation\u2014the SOX2 gene\u2014which is also frequently associated with other physical abnormalities. In cases of unilateral microphthalmia, however, the likelihood of finding a causative gene mutation appears to be very low.Various stages of eye development may be disrupted in the development of microphthalmia or anophthalmia. If the cause lies in a blood vessel that did not recede properly, vision and anatomy in the other eye were normal in all cases; however, delayed eye growth was observed more frequently. When the cause was due to abnormal closure of the optic vesicle, we more frequently observed cysts next to the eye, as well as cardiac abnormalities. A disruption in the development of the anterior segment of the eye appears to occur more frequently in both eyes than in other groups, which adversely affects the chances of good vision.      <\/p>\n<h2 class=\"wp-block-heading\">Treatment with Conformer Series<\/h2>\n<p class=\"wp-block-paragraph\">The third chapter analyzes the treatment using the conformer series. To date, no other research team has described their results in this way! Furthermore, the conformers were designed and printed using a 3D printer, which is also a significant innovation in the treatment. The first phase of the overall treatment consisted of 3D-printed conformers to stretch the eyelids that were too small and alter the eye socket so that a prosthetic eye could remain securely in place. In the second phase, a highly realistic prosthetic eye was created and fitted. Most of the initial conformers were created based on information from a cast and\/or an MRI scan. The subsequent conformers were printed in larger sizes, then fitted into the eye sockets and ground down as needed. To better predict exactly how much larger the conformers need to be in the future, we measured all dimensions. A total of 174 conformers from 18 children were scanned using a CT scanner, and their height, width, thickness, volume, and surface area were analyzed. The average treatment duration was nearly 3 years, but because some children were followed for a shorter period and others for a longer one, this ranged from 1.3 to 4.8 years. The greatest growth can be expected within the first 10 months of treatment. In cases of severe microphthalmia and anophthalmia, the height and width of the conformers doubled during this period. In the moderate form, they were 1.7 times as high and wide. Unfortunately, no meaningful conclusions could be drawn regarding thickness, volume, and surface area, as these varied too widely. Severely affected eyes were generally treated as soon as possible (within 3 months of birth). In the moderate group, treatment began at an average age of 6 months (ranging from 2 to 16 months of age). We observed that this treatment successfully stretched the eyelid in all children, resulting in improved symmetry: 16 out of 17 had eyelid symmetry of more than 80 percent, meaning the artificial eye side was nearly the same size as the unaffected or least-affected eye. In all cases, a standard artificial eye could be fitted after the stretching procedure. No serious complications were observed, though the socket often becomes unstable when children have a cold. Sometimes this can even cause the conformer to no longer fit, requiring the process to be set back a few steps. Often, however, the progress is eventually regained. When the conformer is first inserted, an inflammatory reaction often occurs, but this subsides quickly.                       <\/p>\n<h2 class=\"wp-block-heading\">The next steps in the investigation<\/h2>\n<p class=\"wp-block-paragraph\">The next two chapters will focus on developing the orbital dimensions as measured by ultrasound, and the cosmetic outcomes as recorded through 3D photography. We are currently working hard on this. Jelmer also discussed his progress on the 3D-printed ocular prosthesis. The goal, of course, is to eventually start with a completely natural-looking eye right from the first phase, rather than a temporary conformer. An article on this topic was previously published in this magazine. You can find the full published article at: https:\/\/doi.org\/10.1089\/3dp.2021.0048. In it, we describe a method for printing a prosthesis in color, with textured iris and sclera, and a natural pupil (a hole instead of a dot), all printed in a single session. By combining this \u201cproof of concept\u201d with previous topics discussed in this article, the full 3D printing of custom-made prostheses is becoming increasingly within reach. However, there are still some challenges, and it is also too early to say whether this workflow offers added value for patients who have undergone evisceration or enucleation. Developments are currently in full swing, and a team from the Industrial Design program at TU Delft is also involved in this effort.        <\/p>\n","protected":false},"excerpt":{"rendered":"<p>During the Online Oogcontact Meeting, ophthalmologists Dyonne Hartong and Annabel Groot and ocularist Jelmer Remmers provided an update on the progress of their research, which has been ongoing since 2018. The research is divided into several chapters and is expected to result in a dissertation to be defended at the University of Amsterdam. Annabel discussed the first few chapters, a large portion of which has already been published in scientific journals. This is important because it allows ophthalmologists and scientists around the world to learn from their experiences with anophthalmia and microphthalmia.     <\/p>\n","protected":false},"featured_media":6439,"template":"","meta":{"_acf_changed":false,"_daextauttol_enable_tooltips":""},"library_cat":[111],"class_list":["post-6438","library_pt","type-library_pt","status-publish","has-post-thumbnail","hentry","library_cat-anophthalmia-and-microphthalmia"],"acf":[],"permalink_manager":null,"_links":{"self":[{"href":"https:\/\/ver-ooginoog.nl\/en\/wp-json\/wp\/v2\/library_pt\/6438","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/ver-ooginoog.nl\/en\/wp-json\/wp\/v2\/library_pt"}],"about":[{"href":"https:\/\/ver-ooginoog.nl\/en\/wp-json\/wp\/v2\/types\/library_pt"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/ver-ooginoog.nl\/en\/wp-json\/wp\/v2\/media\/6439"}],"wp:attachment":[{"href":"https:\/\/ver-ooginoog.nl\/en\/wp-json\/wp\/v2\/media?parent=6438"}],"wp:term":[{"taxonomy":"library_cat","embeddable":true,"href":"https:\/\/ver-ooginoog.nl\/en\/wp-json\/wp\/v2\/library_cat?post=6438"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}