Dear Editor,
The interesting article by Kumar et al.[1] may require further discussion.
Neovascularization elsewhere (NVE) is not very common in CRVO, and imaging of the same would be interesting.[2] Moreover, the evidence of neovascular glaucoma (NVG) in the right eye (which did not show anterior segment new vessels) should be elaborated.[1]
Burgansky-Eliash et al.[3] reported two patients with hypotony (intraocular pressure/IOP: 2 and 6 mm Hg, respectively) and anterior rotation of the ciliary body (ARCB) on ultrasound biomicroscopy (UBM) after trabeculectomy presumably due to “ocular decompression.” UBM-features improved in the first patient after topical atropine 1% twice daily; however, IOP remained low (3 mm Hg). In the second patient, UBM-findings improved after cataract surgery and pars-plana anterior vitrectomy. This patient had “elevated and pale” (avascular looking) bleb. Final IOP was not reported in both cases.[3]
The primary cause of hypotony, shallow anterior chamber (AC), and ARCB might be overfiltration through the bleb or tube (Sherwood-slit), rather than “malignant glaucoma” in both case reports.[1,3] Because IOP was low, use of glaucoma in “hypotonous malignant glaucoma” (HMG) may be self-contradictory. Existence of such an entity may need research.
Overfiltration immediately after trabeculectomy tends to settle over time, and aqueous misdirection should be a diagnosis of exclusion after all efforts of treating overfiltration have been exhausted and IOP is normal or high. The patient’s[1] IOP improved on pressure patch and medical management, suggesting a component of overfiltration. Absent aqueous pockets in the vitreous cavity also point against aqueous misdirection.[1] Other management options (including reducing frequency of steroid, reformation of AC, and ligation of tube) should have been considered before planning anterior vitrectomy.
The results of longer follow-up in this patient and the method of using prolene for ligature of tube should be discussed.
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References
- 1.Kumar S, Singla E, Ichhpujani P, Rehman O. Hypotonous malignant glaucoma following glaucoma drainage device implantation. Indian J Ophthalmol Case Rep. 2021;1:512. [Google Scholar]
- 2.Hayreh SS, Zimmerman MB. Ocular neovascularization associated with central and hemicentral retinal vein occlusion. Retina Phila Pa. 2012;32:1553–65. doi: 10.1097/IAE.0b013e318246912c. [DOI] [PubMed] [Google Scholar]
- 3.Burgansky-Eliash Z, Ishikawa H, Schuman JS. Hypotonous malignant glaucoma:Aqueous misdirection with low intraocular pressure. Ophthalmic Surg Lasers Imaging Off J Int Soc Imaging Eye. 2008;39:155–9. doi: 10.3928/15428877-20080301-03. [DOI] [PubMed] [Google Scholar]