Non-arteritic ischemic optic neuropathy followed by intravitreal bevacizumab injection: Is there an association?

The authors mention that one bilateral case of isolated lacrimal gland amyloidosis has been reported. We wish to draw attention to one of the cases reported by Cheng et al.,[4] who had bilateral isolated lacrimal gland involvement with amyloidosis. Also, Knowles et al.,[5] have described a case with serial bilateral lacrimal gland amyloidosis without systemic disease (primary localized orbital amyloidosis). This raises the total number of cases previously reported to have bilateral isolated lacrimal gland amyloidosis to at least three.

The authors report that approximately 24 cases of primary localized amyloidosis of orbit have been reported. However, we believe that this number is likely to be higher. In a review article by Taban et al., [2] the authors reviewed 31 cases of primary orbital amyloidosis including one of their own. There have been a few further reports after that including a large series by Leibovitch et al. [3] The authors mention that one bilateral case of isolated lacrimal gland amyloidosis has been reported. We wish to draw attention to one of the cases reported by Cheng et al., [4] who had bilateral isolated lacrimal gland involvement with amyloidosis. Also, Knowles et al., [5] have described a case with serial bilateral lacrimal gland amyloidosis without systemic disease (primary localized orbital amyloidosis). This raises the total number of cases previously reported to have bilateral isolated lacrimal gland amyloidosis to at least three.
Hertel's exophthalmometer is designed to measure axial proptosis and is unable to measure ocular displacement. We would value being educated as to how the authors were able to measure the displacement with the help of a Hertel's exophthalmometer. Perhaps the authors are merely implying that apart from having 2 mm of axial proptosis, the patient also had 2 mm of displacement.
Lastly, was any reoccurrence noted? Recurrence has been said to occur in approximately one-third of cases as total excision is usually not possible in these patients.

Comments on: Nuclear management in manual small incision cataract surgery by snare technique
Dear Editor, I read with interest the article entitled "Nuclear management in manual small incision cataract surgery by snare technique" by Bhattacharya. [1] In the beginning of the article itself, it is stated "Keener in 1983 was the first to snare the nucleus into two halves and bring the fragments out through a sclerocorneal flap valve incision. [1] " On further search [2] I found that Gerald Keener in 1983 prepared a snare from an 18-19-G blunt-tipped needle and a 32-G stainless steel wire. After the nuclear prolapse into the anterior chamber, he positioned the wire loop around the nucleus. The loop was then shortened by pulling it back, resulting the nucleus to be divided into two. This is exactly the same technique described by Dr. Bhattacharya in his article. Therefore Dr. Bhattacharya is reviving a technique originally developed by Keener in 1983, [2] after a prolonged period of dormancy.
Dr. Bhattacharya has admitted in his article abstract that much evidence of this technique is not available in literature, as its popularity grew through live surgical workshops and small interactive conferences. However, can a video clip in a live surgical workshop predict postoperative endothelial count or intraocular pressure (IOP) three months postoperatively? Certainly not. Therefore I seriously doubt whether a new surgical technique which is meant to be applied on human beings should be accepted without a number of clinical (i.e. surgical) trials maintaining a proper research methodology.
In an age-and sex-matched adequately sized sample, selected by predetermined inclusion and exclusion criteria, with standardized surgical technique, results of a number of intraoperative and postoperative parameters are to be analyzed and compared with other techniques, before being presented to peers for acceptance. The author did not do that. Let me put forward some related surgical techniques which were presented by their respective authors in a scientific manner as described.
Francisco et al. reported many data in relation to their surgical technique of manual phacofragmentation using specially designed nucleotome in 50 eyes of 50 patients. [3] Preoperative and postoperative endothelial counts were evaluated, incidence of intra and postoperative complications (like intraoperative intracameral bleeding, postoperative corneal edema, iritis, raised IOP) were enumerated, postoperative astigmatisms were determined. Take another example. Akura et al., who used claw vectis for nucleus delivery, presented in their article [4] the results of their technique on 620 eyes of 510 patients. Therefore any new maneuver/ instrumentation in the anterior chamber should be backed by adequate data regarding its safety and efficacy before being advocated for large-scale public application.

Non-arteritic ischemic optic neuropathy followed by intravitreal bevacizumab injection: Is there an association?
Dear Editor, There were no identifiable risk factors for NAION in her case apart from the age. Intraocular pressures were found to be normal during pre and post-treatment phase. One possible explanation can be a compromise in the vascular integrity of the optic nerve vessels as vascular endothelial growth factor (VEGF) participates in the maintenance of vascular systems in adults. [1] To date, pegaptanib and ranibizumab in humans have not shown adverse effects on normal retinal or choroidal vasculature but bevacizumab has been proven to be more potent than its counterparts in the terms of a longer half life and much higher systemic levels. [2] We also want to highlight the direct neuroprotective role of VEGF which again is compromised with the use of bevacizumab. [3] Blockage of VEGF with bevacizumab has been associated with stroke and reversible focal posterior leukoencephalopathy of the brain. [4] It is known to cause mitochondrial damage in the inner segments of photoreceptors and apoptosis in the retina. [5] In animal models VEGF inhibition has been implicated in diabetic and ischemic neuropathy. [2] Chronic inhibition of VEGF-A in normal adult animals resulted in loss of retinal ganglia. [2,5] We are aware of the fact that this could have been a coincidence but still strongly believe that it is not possible to ignore the compromised vascular integrity and lack of neuroprotection as a possible cause of NAION in our patient. We need to take into consideration the frequency of drug administration especially in the case of bevacizumab due to its presumed higher potency.