Illuminating Dead Bag Syndrome

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This month, News in Review highlights selected papers from the original papers sessions at AAO 2022. Each was chosen by the session chairs prior to the meeting because it presents important news or illustrates a trend in the field. Only three subspecialties are included here; papers sessions also were held in six other fields.

Some two decades ago, Samuel Masket, MD, began to describe cases of late postoperative IOL dislocation in which the capsular bag appeared di­aphanous and floppy and was unable to support the IOL within it. These cases shared some—but not all—character­istics with other conditions that lead to post-op in-the-bag IOL dislocation.

Now, researchers from the Univer­sity of Utah are reporting clinical fea­tures and histopathological findings of the condition that has become known as “dead bag syndrome.”^1-3

EXAMPLE. This image shows an in-the-bag dislocated IOL in a patient with dead bag syndrome. The capsular bag is very clear, without fibrotic changes or proliferative material.

How often does it occur? “In terms of prevalence, it is not that common,” said Liliana Werner, MD, PhD, at the John A. Moran Eye Center in Salt Lake City. She noted that surgeons who are aware of it may see five cases per year, and those in specialty practices may see one a month or more. Even so, there has been a recent uptick in cases, said Nick Mamalis, MD, also at the Moran Eye Center.

Under the microscope. “What is im­portant about this study is that we were able to evaluate the capsular bag from these patients and assess the pathologic findings for the first time,” Dr. Mamalis said.

The Utah case series involved 10 patients with suspected dead bag syn­drome, from whom eight IOLs and sev­en capsular bags were removed because of subluxation or dislocation. No signs of zonular instability, a hallmark of IOL dislocation in many cases of pseudoex­foliation, were noted during the initial uneventful implantation surgeries, which occurred a mean of 10.6 years before explantation.

Histopathological examination of the seven capsular bags showed cap­sular thinning and/or splitting. Lens epithelial cells (LECs), believed to contribute to the health and structur­al integrity of the lens capsule, either were rarely seen or completely absent from the inner surface of the capsule. In addition, there was no association between any particular IOL design or material (either three-piece silicone or single-piece hydrophobic acrylic) and dead bag syndrome.

A distinct entity. While the etiology of dead bag syndrome is unknown, the researchers hypothesize that late postoperative zonular failure is related to capsule splitting and delamination that occurs at the level of zonular attachments.

And even though dead bag syndrome shares some features with other late postoperative conditions that predis­pose to in-the-bag IOL dislocation, it is a distinct entity, the researchers said. For instance, although patients with pseudoexfoliation may show signs of zonular instability during cataract sur­gery with IOL implantation, these signs are usually absent in dead bag syn­drome. Moreover, there is no capsular splitting in pseudoexfoliation—and no evidence of pseudoexfoliation in dead bag syndrome.

True exfoliation manifests with capsular splitting and delamination, but it is not commonly associated with zonular weakness. In addition, exfo­liation patients typically are in their 70s and 80s, and they often have been exposed to high heat or infrared radi­ation. However, in this study, patients with dead bag syndrome were younger (mean age, 66 years), with no known exposure to heat or radiation.

Unanswered questions. The results, particularly those regarding scarcity of LECs, have had some surgeons ques­tioning whether capsular polishing during cataract surgery may trigger the syndrome. However, no established association between polishing and dead bag syndrome has been found to date.

“So where does the problem start? In the LECs, or in the capsule itself?” wondered Dr. Werner. “We need further study to understand the relationship between LECs and capsular strength. There are many unanswered questions, not only about the etiology of this syndrome but also about its manifesta­tions.”

—Miriam Karmel

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1 Culp C et al. J Cataract Refract Surg. 2022;48:177-184.

2 Mamalis N et al. Clinical and histopathological findings in the dead bag syndrome. Paper pre­sented at: AAO 2022; Oct. 1, 2022; Chicago.

3 Werner L. “The Dead Bag Syndrome.” Best-of-show video presented at: AAO 2022; Sept. 30-Oct. 3, 2022; Chicago.

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Relevant financial disclosures—Drs. Mamalis and Werner: None.

For full disclosures and the disclosure key, see below.

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