Intracapsular Hematoma

Key Points at a Glance

Key Points of This Disease

• Endocapsular hematoma (ECH) is a rare condition in which blood accumulates between the posterior surface of the intraocular lens (IOL) and the posterior lens capsule.
• It often occurs as a late complication of cataract surgery.
• Reports are particularly common in cases where cataract surgery and glaucoma surgery are combined.
• It was first reported by Thomas et al. in 1989.
• Vascular abnormalities such as diabetic retinopathy and iris neovascularization are risk factors.

1. What is endocapsular hematoma?

Endocapsular hematoma (ECH) is a rare complication after intraocular surgery in which blood accumulates between the posterior surface of the intraocular lens (IOL) and the anterior surface of the posterior capsule.

It was first reported in 1989 by Thomas et al. in a 72-year-old woman who developed it after combined extracapsular cataract extraction with trabeculectomy and posterior chamber lens implantation. On postoperative day 2, blood accumulation and fluid level were noted in the capsular bag behind the IOL. In 1991, Hagan and Gaasterland reported a series of 6 cases, first using the term “endocapsular hematoma” and proposing treatment by Nd:YAG laser posterior capsulotomy.

Q When does endocapsular hematoma occur?

A

In most cases, it occurs as a late complication of cataract surgery. Although acute cases occurring early after surgery have been reported, many cases are discovered some time after surgery.

2. Main symptoms and clinical findings

Subjective symptoms

Detailed descriptions of subjective symptoms of endocapsular hematoma are limited, but blood accumulation behind the IOL can cause decreased visual acuity. If the amount of blood is small, it may be asymptomatic.

Clinical findings

Slit-lamp examination reveals the following findings:

• Blood accumulation behind the IOL: Blood is present in the closed space between the posterior surface of the IOL and the posterior capsule.
• Fluid level formation: Blood settles downward due to gravity, forming a fluid level.

3. Causes and risk factors

Endocapsular hematoma can occur in the following situations:

• Combined cataract and glaucoma surgery: Most common when phacoemulsification is performed simultaneously with trabeculectomy or non-penetrating glaucoma surgery.
• Thrombolytic therapy: Reported as a rare ocular hemorrhage following thrombolytic therapy with streptokinase.
• UGH syndrome: Reported in association with uveitis-glaucoma-hyphema syndrome.
• Trauma: Can occur following ocular trauma.

Risk factors are as follows:

• Neovascularization of the iris or lens capsule: Preexisting new blood vessels are prone to bleeding due to friction with the intraocular lens.
• Diabetic retinopathy: Increased vascular fragility.
• Weak zonules: Leads to instability of the intraocular lens, causing friction.
• Vascular disease: Systemic vascular disorders increase the risk.

Prevention and Daily Care

After cataract surgery, please undergo regular follow-up examinations. Especially if glaucoma surgery was performed simultaneously or if you have diabetes, watch for postoperative abnormalities. If you notice changes in vision, see an ophthalmologist promptly.

Q What types of surgery are more likely to cause this?

A

It can occur after cataract surgery alone, but is particularly reported in cases combined with glaucoma surgery such as trabeculectomy. Recently, it has also been reported after combined cataract surgery and trabectome, a minimally invasive glaucoma surgery (MIGS). Friction between the intraocular lens and the capsule is thought to contribute to bleeding.

4. Treatment and Course

The treatment strategy is determined by the amount of blood and the impact on visual function.

• Observation: For small amounts of bleeding or asymptomatic cases, wait for spontaneous resolution. In a report of 10 cases by Radax et al., spontaneous absorption over several months without Nd:YAG incision was documented.
• Nd:YAG laser posterior capsulotomy: In the original report by Hagan and Gaasterland, YAG posterior capsulotomy was performed in 3 of 6 cases, and visual recovery was achieved by draining the intracapsular blood into the vitreous cavity. Recent case reports also show rapid visual function recovery with Nd:YAG posterior capsulotomy.
• Invasive procedures: Considered when conservative therapy or laser treatment does not improve the condition, but they are infrequent.

Q Should an intracapsular hematoma be treated?

A

In cases where the amount of blood is small and does not affect visual function, observation is recommended to wait for spontaneous absorption. When accompanied by decreased vision, Nd:YAG laser posterior capsulotomy to drain the intracapsular blood into the vitreous cavity is considered effective.

6. Pathophysiology and Detailed Mechanism

Early reports referred to this condition as “endocapsular hyphema.” However, due to its location, insufficient blood cell volume, and the fact that blood is not spontaneously reabsorbed, this term is considered inaccurate, and the term “intracapsular hematoma” is now used.

Two hypotheses have been proposed regarding the origin of the blood.

• Leakage from anterior vitreous hemorrhage: Initially, there was a hypothesis that blood leaked through the posterior capsule.
• Inflow from surgical incision: This is currently the more accepted theory. In acute postoperative cases, blood from the surgical incision is thought to flow into and accumulate in the closed space behind the intraocular lens.

The space between the intraocular lens and the posterior capsule forms a closed compartment. Therefore, once blood accumulates, it is not exposed to the aqueous humor circulation of the anterior chamber and is less likely to be absorbed spontaneously, unlike typical anterior chamber hemorrhage (hyphema). This characteristic is the basis for calling it a “hematoma” rather than a “hyphema.”

Q Why is blood not absorbed spontaneously?

A

The space between the posterior surface of the intraocular lens and the posterior capsule is a closed compartment. Because it is isolated from the aqueous humor circulation of the anterior chamber, spontaneous absorption of blood is less likely to occur, unlike typical anterior chamber hemorrhage. This is also why it is called a “hematoma” rather than a “hyphema.”

References

1. Thomas R, Aylward GW, Billson FA. “In-the-bag” hyphaema — a rare complication of posterior chamber lens implantation. Br J Ophthalmol. 1989;73(6):474-475. PMID: 2751983
2. Hagan JC 3rd, Gaasterland DE. Endocapsular hematoma. Description and treatment of a unique form of postoperative hemorrhage. Arch Ophthalmol. 1991;109(4):514-518. PMID: 2012552
3. Radax U, Menapace R. Endocapsular hematoma with biconvex posterior chamber intraocular lenses. J Cataract Refract Surg. 1994;20(6):634-637. PMID: 7837075
4. Dhawan B, Soni R, Singh R, Vig V. Endocapsular hematoma: a rare form of ocular hemorrhage after thrombolysis with streptokinase. N Am J Med Sci. 2014;6(8):425-427. PMID: 25210679
5. Nejabat M, Khalili MR, Masihpour N, et al. Endocapsular hematoma as an uncommon early postoperative complication of phacoemulsification with intraocular lens implantation surgery. Indian J Ophthalmol. 2020;68(10):2282-2283. PMID: 32971693
6. Chang EL, Apostolopoulos N, Mir TA, Freedman IG, Teng CC. Large hyphema following femtosecond laser-assisted cataract surgery (FLACS) and trabectome resulting in endocapsular hematoma. J Curr Glaucoma Pract. 2022;16(3):195-198. PMID: 36793266