Haab striae are breaks in the Descemet membrane associated with congenital glaucoma,1,2 and are found in approximately 50% of children with congenital glaucoma.3 The presence of Haab striae in the context of elevated or borderline intraocular pressure (IOP) confirms the diagnosis of congenital glaucoma, especially in older children with clear cornea on presentation. However, not all striae are immediately apparent on examination with biomicroscopy, because many children with congenital glaucoma present with corneal edema.
Anterior segment optical coherence tomography (AS-OCT) is a noninvasive tool that provides corneal imaging approaching histological resolution. Although used extensively in the adult glaucoma population and in corneal pathologies, the role of OCT and AS-OCT in the pediatric glaucoma population has not been well reported.4
We present an observational case series in which we describe the AS-OCT findings of Haab striae in infants with primary congenital glaucoma and demonstrate its role in the evaluation of congenital glaucoma.
We present a case series of three eyes in three patients with congenital glaucoma presenting to the Bascom Palmer Eye Institute. All study participants underwent examination under anesthesia (EUA), which included IOP measurements using Tono-Pen (Reichert, Inc., Depew, NY), anterior segment and dilated fundus examinations, cycloplegic retinoscopy, external photographs, and portable AS-OCT imaging (iStand; Optovue, Inc., Fremont, CA). None of the patients had any other (non-glaucomatous) corneal pathologic features, cataract, or retinal disease.
A 4-month-old male infant was referred due to a 1-week history of new-onset cloudy corneas, photophobia, and epiphora. On examination, the right eye was central and steady but did not maintain fixation. The left eye was central, steady, and maintained. Cycloplegic retinoscopy showed −2.50 sphere in the right eye and −0.50 sphere in the left eye. On EUA, IOP was 24 mm Hg in the right eye and 25 mm Hg in the left eye. Horizontal and vertical corneal diameters measured 13 mm in the right eye and 12 mm in the left eye. In the right eye, horizontal Haab striae were noted across the visual axis from the 3- to 9-o’clock positions (Figure 1). Haab striae were not present in the left eye. Gonioscopy revealed open angles in both eyes. Cup-to-disc ratio was 0.6 in the right eye and 0.3 in the left eye. A-scan echography showed a right eye axial length of 22.8 mm and a left eye axial length of 21.6 mm, both of which are above the normal range for the child’s age. AS-OCT imaging of the Haab striae showed the sharp edges of the broken Descemet membrane bulging into the anterior chamber and stromal edema at the area between the broken Descemet flaps (Figure 1). The diagnosis of primary congenital glaucoma in both eyes was made and the patient underwent successful circumferential trabeculotomy procedures in both eyes.
External photograph and anterior segment optical coherence tomography (AS-OCT) of patient 1. Horizontal Haab striae are seen involving the visual axis (left). AS-OCT showing partial cross-section of the Haab striae demonstrated the sharp edges of the broken Descemet’s membrane. Note the localized stromal edema at the area between the broken Descemet flaps (right).
A 3-month-old male infant presented to the emergency department with redness, poor fixation, and a buphthalmic appearance of the left eye. Cycloplegic retinoscopy showed −0.50 +1.50 × 030 in the right eye and −4.50 +3.00 × 180 in the left eye. On EUA, IOP was 8 mm Hg in the right eye and 22 mm Hg in the left eye. Examination of the right eye was unremarkable. The cornea of the left eye measured 13 mm horizontally and vertically. There was a suspected isolated Haab stria peripherally, although this could not be seen clearly on portable slit-lamp examination due to significant corneal haze (Figure 2). Gonioscopy showed an open angle with wispy iris processes. The cup-to-disc ratio was 0.8. Echography showed an axial length of 22.5 mm. AS-OCT clearly demonstrated the peripheral break in Descemet membrane, confirming the finding of a single Haab stria (Figure 2). Primary congenital glaucoma was diagnosed in the left eye and the patient underwent circumferential trabeculotomy.
External photograph and anterior segment optical coherence tomography (AS-OCT) of patient 2. Peripheral, circumferential Haab stria is seen parallel to the limbus outside the visual axis with concurrent corneal opacity (arrow, left). AS-OCT demonstrated a smooth thickened protruding edge of the Haab stria (right).
A 9-month-old male infant presented with bilateral photophobia, blepharospasm, and epiphora. The patient fixated and followed with both eyes. Cycloplegic refraction showed −5.50 sphere in the right eye and −6.50 +1.50 × 030 in the left eye. On EUA, IOP was 25 mm Hg in the right eye and 29 mm Hg in the left eye. Horizontal and vertical corneal diameters were 13 mm in both eyes. The right eye showed mild diffuse corneal haze with numerous Haab striae involving the visual axis (Figure 3). Similar corneal findings were observed in the left eye. The cup-to-disc ratio was 0.85 in both eyes. The axial length was 24.5 mm in the right eye and 24.6 mm in the left eye. AS-OCT demonstrated the thickened and curled edges of the Haab striae (Figure 3). The patient was diagnosed as having bilateral primary congenital glaucoma and underwent trabeculotomy in both eyes.
External photograph and anterior segment optical coherence tomography (AS-OCT) of patient 3. Multi-directional Haab striae involving the visual axis (left). AS-OCT showed the classic curled thickened edges of the broken Descemet membrane (right).
The presence of pathologic ocular hypertension in an elastic infant eye may result in Haab striae. In the acute stage, striae are associated with transient corneal edema.1 Long term, these corneal abnormalities may lead to dense amblyopia due to high and irregular refractive errors, which is the main etiology of poor vision in infantile-onset glaucoma.3
Haab striae can appear similar to other corneal pathologies such as posterior polymorphous dystrophy and iridocorneal endothelial syndrome at the slit-lamp level.1,5 When the Descemet membrane ruptures, the edges have a tendency to curl over time and have a thickened appearance, as classically described in histopathology literature.1 It is also possible that contact of the curled edges with the overlying corneal stroma entraps keratocytes, which induces proliferation.1 In two of our cases, AS-OCT showed that the edges of the Haab striae were curled and thickened (Figures 2–3, right). However, in one case (Figure 1, right), the edges of the broken Descemet membrane were thin, bulged into the anterior chamber, and did not contact the underlying stroma. This patient was seen 1 week after the onset of symptoms and before any Haab striae developed in the second eye. We speculate that this AS-OCT image may have captured an early appearance of Haab striae accompanied by corneal edema, which is usually observed in the acute phase, whereas most pathologic specimens probably reflect more chronic changes, including keratocyte proliferation and curly, thickened edges. This suggests that Haab striae evolve over time and its effect on corneal biomechanics may be dynamic.
AS-OCT has been extensively studied in adult patients with glaucoma and in corneal pathologies. In the pediatric glaucoma population, OCT is commonly used to measure and characterize the retinal nerve fiber layer6,7; however, its use in the assessment of Haab striae in pediatric patients with glaucoma is novel and previously undescribed. Although our cases were more obvious cases of glaucoma (due to the high IOP, disc cupping, and enlarged corneal diameter), this is a proof of concept that AS-OCT can be useful in cases presented with borderline findings and subtle corneal changes. AS-OCT can be especially helpful in cases where corneal haze limits visualization of Haab striae, such as in the second case we presented. It would be interesting to track the evolution of Haab striae over time and to correlate changes in AS-OCT appearance with changes in the IOP and cycloplegic refraction, to gain insight on the effect of pathologic IOP on the elastic infant eye.
- Cibis GW, Tripathi RC. The differential diagnosis of Descemet’s tears (Haab’s striae) and posterior polymorphous dystrophy bands: a clinicopathologic study. Ophthalmology. 1982;89:614–620. doi:10.1016/S0161-6420(82)34747-8 [CrossRef]
- Mastropasqua L, Carpineto P, Ciancaglini M, Nubile M, Doronzo E. In vivo confocal microscopy in primary congenital glaucoma with megalocornea. J Glaucoma. 2002;11:83–89. doi:10.1097/00061198-200204000-00002 [CrossRef]
- Patil B, Tandon R, Sharma N, et al. Corneal changes in childhood glaucoma. Ophthalmology. 2015;122:87–92. doi:10.1016/j.ophtha.2014.07.029 [CrossRef]
- Cauduro RS, Ferraz Cdo A, Morales MS, et al. Application of anterior segment optical coherence tomography in pediatric ophthalmology. J Ophthalmol. 2012;2012:313120.
- Laganowski HC, Sherrard ES, Muir MG. The posterior corneal surface in posterior polymorphous dystrophy: a specular microscopical study. Cornea. 1991;10:224–232. doi:10.1097/00003226-199105000-00008 [CrossRef]
- Prakalapakorn SG, Freedman SF, Lokhnygina Y, et al. Longitudinal reproducibility of optical coherence tomography measurements in children. J AAPOS. 2012;16:523–528. doi:10.1016/j.jaapos.2012.08.011 [CrossRef]
- Srinivasan S, Addepalli UK, Rao HL, Garudadri CS, Mandal AK. Spectral domain optical coherence tomography in children operated for primary congenital glaucoma. Br J Ophthalmol. 2014;98:162–165.