717 e-Letters

  • Comments on Outcome of trabeculectomy versus Ahmed glaucoma valve implantation in the surgical management of glaucoma in patients with Sturge–Weber syndrome

    We read with interest the article by Sarker et al(1) in which they compared the outcomes of trabeculectomy versus Ahmed glaucoma valve (AGV) implantation in Sturge–Weber syndrome (SWS) patients with secondary glaucoma aged 11-62 years. As it noted in the paper, the authors found that complete success rates after 24 months were 80% and 70% in the AGV and trabeculectomy groups, respectively, and qualified success rates were 90% and 85% at same period in the AGV and trabeculectomy groups, respectively. We were delighted to get the conclusion that both AGV implant and trabeculectomy appeared to be safe and efficacious in controlling glaucoma secondary to SWS.
    As it reported by Mohamed et al., the complete success rate and qualified success rate (intraocular pressure≤17mmHg) of trabeculectomy reported were 80% and 100% at 12 postoperative follow-up month, respectively(2). However, the qualified success rate (90%) of AGV implantation in SWS patients with secondary glaucoma is higher than that reported by Hamush et al. (79%)(3) and Kaushik et al. (76%)(4) at 2 years of follow-up. Meanwhile, the trabeculectomy with MMC success rate in this study was comparable to other studies about primary glaucoma(5, 6), but the success rate of tube shunt surgery was higher than in prior reports. The qualified success rate of Baerveldt implantation for patients who not had undergone previous incisional ocular surgery was 73% in Primary Tube Versus Trabeculectomy (PTVT) study(6) and 75% rep...

    Show More
  • Management of Glaucoma During Pregnancy

    Title: Management of Glaucoma During Pregnancy

    Author: Angelo P. Tanna

    Department of Ophthalmology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
    Division of Ophthalmology, Ann & Robert H. Lurie Children’s Hospital of Chicago, Chicago, Illinois, USA

    Conflicts of Interest Disclosure:
    APT: Consultant to Ivantis, Sandoz, and Zeiss

    APT is supported by an unrestricted departmental grant from Research to Prevent Blindness, NY, NY

    Corresponding Author:
    Angelo P. Tanna, M.D.
    Department of Ophthalmology
    Northwestern University Feinberg School of Medicine
    645 N. Michigan Ave., Suite 440
    Chicago, IL 60611
    Telephone: 312-908-8152
    Fax: 312-503-8152
    E-mail: atanna@northwestern.edu

    Dear Editor:

    I read with interest the work of Doctor Hashimoto and colleagues on the risk of adverse neonatal outcomes (congenital anomalies, preterm birth, low birth weight) associated with maternal exposure to intraocular pressure-lowering medications during pregnancy.1 They used a large Japanese claims database and state-of-the-art statistical methodology to evaluate the frequency of adverse events in a cohort of live births of 91 women who had “at least one dispensation of IOP-lowering medications during the first trimester,” compared to that observed in 735 women with glaucoma or...

    Show More
  • Presumptive JC viral retinitis

    Thank you for raising the issue of abbreviations entering the virological lexicon which might give rise to confusion and misunderstanding. Over a decade has elapsed since our patient report was published and the source material is not retrievable. However, our recollection is the patient was discussed contemporaneously at the MDT and the viral aetiology, radiology findings and medical management determined and documented, from which the data was sourced for the 2008 report. Plausible as it may seem, it is not possible to test the veracity of the suggestion that the names ‘Jamestown Canyon’ and ‘John Cunningham’ might have been transposed during that MDT many years after the event, paper records are not kept indefinitely in NHS practice and ethics in medical publishing demands that patient identifiers are not described or retained in order to preserve anonymity. Perhaps the latter should have been considered over half a century ago when JC virus was first identified in the brain of the unfortunate patient after whom the eponymous pathogen was christened
    (Padgett BL, Walker DL; et al. (1971). "Cultivation of papova-like virus from human brain with progressive multifocal leucoencephalopathy". Lancet. 1 (7712):
    1257–60. doi:10.1016/S0140-6736(71)91777-6)

  • Change in the ophthalmoscopical optic disc size and shape in a 10-year follow-up: a short comment

    I read with interest the article by Jonas et al 1. The main purpose of the authors was to explore associations between a disc size change and other morphological parameters. Indeed, many non-ophthalmic and game-changing parameters are associated with disc size change and other morphological parameters, such as the serum lipids 2 dietary factors (such as lutein, zeaxanthin, and omega-3 fatty acids) 2-4, medications (such as lipid-lowering agents) 2, genetic susceptibility, body mass index, age and sex 3, among which only age and sex are addressed in their retrospective analysis.

    According to the authors, decrease in the ophthalmoscopic disc size in the myopic eyes during the 10-year follow up, is likely related to a shift of the Bruch’s membrane opening as the inner of the three optic nerve head canal layers into the direction of the fovea. While their interpretations can be partly true, their attributed mechanism is subject to many biases.

    Firstly, changes in ophthalmoscopical optic disc size and Bruch’s membrane are a function of macular pigment optical density 5-7, which in turn is a function of dietary carotenoid intake 8;9. Tong et al 10 have shown before that macular pigment optical density (MPOD) is inversely associated with axial length in Chinese subjects with myopia, suggesting that carotenoid intake, particularly lutein, is associated to axial length as well. Another study with a smaller sample size (45 eyes of 32 patients) with a different mean a...

    Show More
  • Beware of abbreviations: John Cunningham (JC) versus Jamestown Canyon virus

    In their 2008 case report, Muqit, et al. describe a case of “presumptive Jamestown Canyon viral retinitis.”1

    Jamestown Canyon virus is a mosquito-borne, single-stranded, ribonucleic acid (RNA) orthobunyavirus that is endemic throughout much of North America.2,3 Infection with Jamestown Canyon virus may be asymptomatic or may result in a general febrile illness, meningitis, and/or meningoencephalitis.2,3 Beyond the above case report by Muqit, et al.,1 and another review article referencing this case report,4 Jamestown Canyon virus has not been reported to cause retinitis or other ocular manifestations.

    Upon close review of the case report by Muqit, et al.,1 we believe the authors are likely describing a case of John Cunningham (JC) virus (a ubiquitous, double-stranded, deoxyribonucleic acid [DNA] human polyomavirus known to cause progressive multifocal leukoencephalopathy [PML] among the immunocompromised)5-7 rather than Jamestown Canyon virus.

    First, the case patient with viral retinitis had underlying human immunodeficiency virus (HIV) infection and a low CD4 lymphocyte count (240 cells/mm3), making him immunocompromised and susceptible to reactivation of the John Cunningham (JC) virus. Second, the case patient had magnetic resonance imaging (MRI) brain findings (i.e., asymmetric, predominantly posterior, confluent, subcortical white matter hyperintensities involving U-fibers) that are classic for John Cunningham (JC) virus-related PML.6,7 In fact,...

    Show More
  • Comment on : Swept source optical coherence tomography angiography in patients treated with hydroxychloroquine: correlation with morphological and functional tests

    We read with great interest the article by Forte et al1, "Swept source optical Coherence tomography Angiography in patients treated with hydroxychloroquine: co-relation of the functional and morphological test." Hydroxychloroquine (HCQ) is a widely used drug for the management of systemic lupus erythematosus and rheumatoid arthritis. Non-invasive tests like optical coherence tomography, optical coherence tomography-angiography, 10-2 visual fields and multifocal ERG (mf-ERG) help in the early detection of the toxicity.2 We would like to highlight here importance of adaptive optics, and various studies done for the early detection of HCQ toxicity. In the study by Forte et al, mf-ERG did not co-relate with the flow changes on OCT-A, however in another observation by Penrose et al (n=6) a depression of signals on multifocal ERG was found in the perifoveal region even when the patients had normal visual acuity and a normal fundus.3Costa et al found significant differences between the micro-perimetry in the patients taking hydroxychloroquine and controls.4 It will be interesting to know the authors take on this. Besides these, adaptive optics is emerging as an important tool to detect the early photo-receptor changes in patients with HCQ toxicity. Adaptive optics help in the direct visualization of the cone mosaic. Stepien et al in their observation on 4 patients observed that adaptive optics showed a loss of cone mosaic in the perifoveal region that corresponded with...

    Show More
  • RE: Associations of ophthalmic and systemic conditions with incident dementia in the UK Biobank

    Shang et al. conducted a prospective study to examine the effect of ophthalmic and systemic conditions on incident dementia (1). The adjusted hazard ratios (HRs) (95% confidence intervals [CIs]) of age-related macular degeneration (AMD), cataract, diabetes-related eye disease (DRED), and glaucoma at baseline for incident dementia were 1.26 (1.05 to 1.52), 1.11 (1.00 to 1.24), 1.61 (1.30 to 2.00), and 1.07 (0.92 to 1.25), respectively. Diabetes, heart disease, stroke and depression at baseline were also significantly associated with an increased risk of dementia. In addition, some combinations of ophthalmic and systemic conditions were at the higher risk for incident dementia. I have a comment about the study.

    Vision impairment is a risk factor of dementia, and poor vision is independently associated with a decline in cognitive function (2). Shang et al. clarified that AMD, cataract, and DRED were risk of incident dementia, and some combinations with systemic conditions accelerated risk of incident dementia. Although glaucoma was not significantly associated with increased risk of al-cause dementia, it was significantly associated with increased risk of vascular dementia. The authors also conducted analysis by excluding data in the first 5 years of follow-up, consistent results were also specified on the combined effects of ophthalmic and systemic conditions on incident dementia. Although the mechanism of increased risk of dementia in combinations with ophthalmic and...

    Show More
  • Goblet cells - sine qua non for conjunctival rehabilitation

    To the editor,

    We read with interest the recent publication by Bertolin et al. (“In vitro establishment, validation and characterisation of conjunctival epithelium outgrowth using tissue fragments and amniotic membrane”). Their validated conjunctival analogue of the simple limbal epithelial transplantation does represent a promising advance in the field. It is, however, interesting to note that the established tissue application was mainly validated on its growth potential and not specifically on its ability to reinstate a healthy ocular mucosal surface.

    Functional validation is of utmost importance, especially as the glued fragments are directly transplanted. This approach circumvents the need for expensive cell culture but also bypasses the stringent release criteria for cell therapies or tissue-engineered transplantation products. We would suggest that before this technique can be considered fully validated, it should be demonstrated that the obtained conjunctival cells contribute to the first line of mucosal defence, i.e. barrier formation. Several conjunctival barriers can be identified, such as intercellular junction complexes, glycocalyx and secreted mucins. Bertolin et al. demonstrated the presence of tight junctions (cfr. ZO-1 protein) and a glycocalyx (cfr. membrane-associated mucin-1), but failed to address the presence of goblet cells. As goblet cells are responsible for the secretion of mucin 5AC, which is the most abundant mucin in the mucin la...

    Show More
  • Is impaired cerebrospinal fluid dynamics the link between dementia and normal-tension glaucoma ?

    We like to congratulate Mullany et al. for their paper on normal-tension glaucoma is associated with cognitive impairment.1 To link normal-tension glaucoma (NTG) to cognitive impairment and therefore to a neurodegenerative process opens a new vista and research approach for glaucoma research. NTG indeed is an intriguing optic neuropathy that presents with a glaucomatous optic disc appearance and visual field loss similar to that seen in primary open angle glaucoma. The main risk factor for glaucoma however, increased intraocular pressure is missing.

    Unlike other cranial nerves the optic nerve is a white matter tract of the brain, enveloped in the meninges (dura, arachnoid and pia mater) and surrounded by cerebrospinal fluid (CSF) on its entire length. And CSF indeed may be the link that connects the neurodegenerative process leading to cognitive impairment and the glaucomatous optic neuropathy in NTG. Recent research demonstrated a relationship between decreased CSF flow, measured in the ventricles and the spinal cord, and cognitive deficit in the elderly.2 In NTG, impaired CSF dynamics was demonstrated with computer assisted cisternography in the subarachnoid space of the intraorbital optic nerve most pronounced in the bulbar region behind the eye globe.3 In a recent publication we found an elevated L-PGDS concentration in the subarachnoid space of the optic nerve in NTG patients with optic nerve sheath compartment syndrome that results in a reduced CSF turnover.4...

    Show More
  • Macular hole surgery should be prioritised, not delayed by observation.

    We would like to congratulate Uwaydat et al. on their large series of spontaneously closed macular holes (MH), which adds new information to the literature.(1) It reinforces the observation that traumatic MH can spontaneously close and that a period of observation in these eyes, where the results of surgery are not clear, is a worthwhile option. However, we disagree with their conclusion that eyes with recent onset small primary MHs should also be observed. The authors don’t suggest a time period for observation but found that the median time for closure for these small holes was 4.4 months.

    The report by Uwaydat et al. has 40 authors and the 60 cases of idiopathic MH were collected over at least a two-year period. Assuming a conservative number of 25 MH cases seen per surgeon per annum, this would give a spontaneous closure rate of ~3%, which is similar to the published literature as the authors review in their article.

    MH are known to enlarge with time, even in the short term. Madi et al, reported that 83% enlarged, by a median of 105 microns in 8 weeks. (2) Similarly, Berton et al recently estimated that holes less than 250 microns enlarge by a mean of 1.67 microns per day, resulting in a similar 100-micron increase in 2 months.(3)

    The anatomical and visual outcomes of surgery are dependent on MH diameter and duration. Holes greater than 300 microns, and with a duration more than four months are less likely to regain 0.3 logMAR or better.(4)...

    Show More