Salzmann nodular degeneration: prevalence, impact, and management strategies

Manual Superficial Keratectomy Is the First Choice Treatment for Salzmann Nodular Degeneration

PURPOSE

This study aimed to describe the optical and topographic changes after manual superficial keratectomy (MSK) for Salzmann nodular degeneration.

METHODS

This was a descriptive, retrospective study. All patients with a clinical diagnosis of Salzmann nodular degeneration were examined at the Cornea Service of the Instituto Clínico Quirúrgico de Oftalmología (ICQO), Bilbao, Spain, and treated with MSK after presenting ocular discomfort and/or decreased visual acuity. The clinical characteristics (including anterior segment optical coherence tomography and Pentacam topography), treatment regimens, surgical procedures, and outcomes were recorded. Descriptive statistics were constructed using mean ± SD, minimum, maximum, and median. The Shapiro-Wilk normality test was used. The Student t test was used to determine significance.

RESULTS

Ten eyes of 9 patients were included in this study: 6 patients (66.6%) were female and 3 were male (33.3%). The mean age was 62.2 years, and the follow-up time was between 5 and 21 months. The best-corrected visual acuity before MSK was 0.20 LogMAR (median) and improved to 0.10 after the surgical procedure. The mean spherical equivalent was reduced from -0.23 ± 3.39 D preoperatively to -1.3 ± 3.0 D postoperatively. Astigmatism decreased between 0.5 and 3.75 D. Topographic irregularity normalized total root mean square from 11,596.4 ± 6854.01 to 4817.2 ± 2725.68 μm.

CONCLUSIONS

MSK is an effective and safe technique for the treatment of Salzmann nodular degeneration when the Bowman layer is preserved. Anterior segment optical coherence tomography and corneal topography are essential tools for the surgical plan and for the detection of corneal aberrations.

[Salzmann nodular degeneration: pathogenesis, clinical characteristics and treatment]

Salzmann nodular degeneration (SND) is a rare non-inflammatory disease observed primarily in middle-aged women. The disease generally occurs in patients with chronic inflammation of the anterior ocular surface. Its etiopathogenesis remains poorly investigated. This literature review describes clinical manifestations, risk factors and diagnostic methods, evaluates the effectiveness of different therapeutic and surgical treatment methods. Understanding of the pathogenetic mechanisms, precise diagnosis and identification of the risk factors can help clinical physicians make the optimal choice of treatment strategy and achieve the best clinical outcomes.

Ocular surface optimization before cataract surgery

The evolution of refractive cataract surgery has increased patient expectations for visual outcomes following cataract surgery. Precise biometry and keratometry are critical for accurate intraocular lens (IOL) selection and favorable surgical outcomes. In patients with the ocular surface disease and corneal pathologies, preoperative measurements can often be erroneous, leading to postoperative refractive surprises and dissatisfied patients. Conditions such as dry eye disease, epithelial basement membrane dystrophy, Salzmann's nodular dystrophy, and pterygia need to be addressed thoroughly before performing cataract surgery to optimize the ocular surface, obtain high-quality preoperative measurements, and ultimately determine the appropriate IOLs. In this review, the various ocular surface pathologies affecting cataract surgery outcomes and options for treatment are discussed and the importance of optimization of the ocular surface before cataract surgery is reviewed.

Netarsudil-Induced Corneal Flattening in a Child with Secondary Open-Angle Glaucoma

We report a case of a child with secondary open-angle glaucoma who developed 6.5 diopters (D) of corneal flattening upon the addition of Rhopressa (0.02% netarsudil dimesylate solution) eye drops to a preexisting treatment regimen of timolol and latanoprost. This change in corneal power reversed after netarsudil, a rho-kinase inhibitor, was discontinued and replaced with Vyzulta (0.024% latanoprostene bunod ophthalmic solution). The 4-year-old female patient presented with bilateral secondary open-angle glaucoma from Paired Box 6 (PAX6)-related aniridia, aphakia, and persistent fetal vasculature. She was started on netarsudil to treat elevated intraocular pressure (IOP) in her right eye, which was not adequately controlled by latanoprost and timolol. Over 4 months, she developed 6.5D of corneal flattening in her right eye. Netarsudil was stopped and the corneal flattening reversed. There is evidence to support the ability of rho kinase inhibitors to increase the healing of the corneal endothelium in addition to their intended IOP-lowering effects. Rho kinase inhibitors may increase cell proliferation and adhesion within the corneal endothelium, hence decreasing apoptosis and promoting cell preservation. If there was an excess of cell proliferation; however, this might induce stromal cells to abnormally secrete enzymes or proteins, such as TGFβ-induced proteins. This could result in corneal fibrosis, thereby flattening the cornea. Further investigation is required to explore this phenomenon and elucidate its mechanism of action. Corneal flattening may be considered as a potential side effect of the use of netarsudil, particularly in young pediatric patients.

Peripheral Hypertrophic Subepithelial Corneal Degeneration

PURPOSE

The purpose of this study was to report a large series of patients with peripheral hypertrophic subepithelial corneal degeneration (PHSCD) and differentiate the condition from Salzmann nodular degeneration (SND).

METHODS

We retrospectively reviewed the charts of 49 patients diagnosed with PHSCD and reported their clinical, refractive, and topographic/tomographic findings.

RESULTS

Most of the eyes were white and quiet. Minimal variable injection was present in a few eyes usually in the presence of pseudopterygium. Typical corneal involvement consists of peripheral circumferential-elevated whitish subepithelial opacities with fine superficial vessels along the limbus and linear deposits of iron in the epithelium along the central edge of the opacification. The typical topographic/tomographic findings consist of flattening directly over the corneal opacification with central flattening aligning with the axis of the opacification. In all subjects, the mean refractive astigmatism was significantly less than the mean topographic/tomographic Sim K astigmatism. Thirty-five eyes underwent surgical excision. The surgical eyes demonstrated significantly less astigmatism and better best-spectacle corrected visual acuity than pre-op. Moreover, all the eyes that underwent surgery for discomfort experienced significant improvement in their symptoms. Histopathology of the keratectomy specimens demonstrated paucicellular subepithelial fibrosis with overlying epithelium that was variable in caliber.

CONCLUSIONS

PHSCD is distinct from SND, primarily occurring in middle-aged women, bilateral and fairly symmetric with larger more peripheral opacities than SND, and absence of inflammatory signs and symptoms.

Optimizing the ocular surface prior to cataract surgery

PURPOSE OF REVIEW

Ocular surface disease can significantly impact the outcomes of cataract surgery. Recent studies have examined the efficacy of several new dry eye disease (DED) therapies, the extent to which epithelial debridement affects keratometric measurements in epithelial basement membrane dystrophy (EBMD) and Salzmann nodular degeneration (SND), and the predictability of refractive error following combined pterygium and cataract removal. This review aims to incorporate these newer studies in updating and further emphasizing the need for careful management and optimization of common ocular surface conditions prior to cataract surgery.

RECENT FINDINGS

Common ocular surface conditions such as DED, EBMD, SND, and pterygium can cause significant irregular astigmatism and higher-order aberrations. Their resolution can substantially alter biometry measurements in preparation for cataract surgery, affecting the final visual outcome. Newer therapies for DED, such as topical lifitegrast and thermal pulsation treatment, can aid in this optimization process. If superficial keratectomy or excisions of lesions on the ocular surface are performed, sufficient healing time is needed to allow the ocular surface to reach stability prior to biometry measurements.

SUMMARY

Ocular surface optimization is key to successful cataract surgery planning and reaching desired outcomes.

Corneal Nodules and Possible Pathologies: A Case Series

Corneal nodular lesions are not uncommon in clinical practice. Diagnosing and managing this condition can be challenging due to its variable causes. This article highlights three cases of corneal nodular lesions. A common clinical pathway for the diagnosis and treatment of cornea nodular lesions is discussed. Two young females and an elderly man presented with a unilateral corneal nodule of variable duration, which was further demonstrated on anterior segment optical coherence tomography (AS-OCT). Several diagnoses were made after thorough history and examination which include herpetic stromal keratitis, phlyctenular keratoconjunctivitis secondary to blepharitis, and Salzmann nodular degeneration. All cases were initiated on topical antibiotics and topical steroids with additional medication or surgical procedure onboard according to their clinical condition. The corneal nodules resolved with scarring after a period of treatment. In conclusion, corneal nodular lesions can be associated with various pathologies. Thorough history, examination, and appropriate investigations are needed to reveal the underlying causes. Serial anterior segment images and AS-OCT are useful to monitor progression and treatment response. Prompt diagnosis and initiation of treatment are crucial to prevent further complications.

Atypical Presentation of Salzmann Nodule: A Case Report and Literature Review

Salzmann’s nodular degeneration (SND) is an unusual corneal condition that is slowly progressive and non-inflammatory in nature. It results in millimetric gray-white to bluish nodules formation anterior to Bowman’s layer of the cornea. It usually affects both eyes in 80% of the cases. These elevated nodules are located near the limbus or in the mid-peripheral cornea, with some exceptions. Salzmann nodule develops following corneal trauma or inflammation. However, it can present idiopathically.

Here, we report an atypical case of idiopathic symptomatic large central SND that was treated successfully with superficial keratectomy.

Myopic Shift after Salzmann Nodule Excision

PURPOSE

To quantify changes in manifest refractive error and mean keratometric power (Km) at 1 month and ≥12 months after Salzmann nodule excision.

SETTING

Clinical practice.

DESIGN

Retrospective consecutive case series.

METHODS

Changes in manifest refractive error (spherical-equivalent), Km, and best-corrected visual acuity (BCVA) were compared for 73 eyes of 58 patients who underwent Salzmann nodule excision. Eyes with ocular comorbidities were excluded. Comparisons between preoperative and postoperative measurements were made by using generalized estimating equation models.

RESULTS

Mean patient age was 66 years, and 68 patients (93%) were female. Spherical-equivalent manifest refractive error was -0.27 ± 2.66 D before nodule excision and became more myopic (-1.10 ± 2.78 D) at 1 month after nodule excision (n=69, p<0.001) with no change at 12 months (n=14, p=0.13). A myopic shift ≥0.5 D occurred in 65% of eyes and ≥1.0 D in 36% of eyes. Km increased from 42.7 ± 2.11 D before nodule excision to 44.2 ± 1.82 D at 1 month after excision (n=49, p<0.001). BCVA improved from 0.18 ± 0.15 logMAR (Snellen equivalent 20/30) before nodule excision to 0.05 ± 0.09 logMAR (20/22, n=69, p<0.001) at 1 month after excision with no change at 12 months (n=14, p=0.73).

CONCLUSIONS

In addition to known changes in cylinder, Salzmann nodule excision is associated with a myopic shift in most eyes caused by corneal steepening. Patients should be counseled about the likelihood of refractive changes, and cataract surgery should be deferred until refractive stability is achieved.

Post-LASIK keratectasia in the context of a thicker than intended flap detected by anterior segment optical coherence tomography

The corneal flap created in LASIK is responsible for most of its advantages in comparison with surface ablation. However, lamellar dissection of the corneal layers in LASIK can also result in serious complications such as corneal ectasia. A 23-year-old man underwent LASIK for correction of −4.75 −2.00@15 in the right eye and −4.50 −2.00@160 in the left eye with a preoperative thinnest corneal thickness of 518 µm/right eye and 513 µm/left eye in 2009. An intended flap thickness and ablation depth in both eyes were 160 µm and 94 µm, respectively, and subsequently, residual stromal bed thickness was 264 µm/right eye and 259 µm/left eye. Several years after surgery, he was referred for the decreased vision. His corrected-distance visual acuity was 0.50 in both eyes. A scissoring reflex was found in retinoscopy. Orbscan imaging was compatible with keratoconus. Anterior segment optical coherence tomography was performed to measure the LASIK flap. It was much thicker (200 µm) than intended (160 µm), and therefore, the residual stromal bed thickness was much thinner. In summary, keratectasia may develop in cases where thicker than expected flaps result in excessive thinning of the residual stromal bed. The obtained results from this case emphasize and remind the importance of intraoperative measurement of flap thickness and using femtosecond and new criteria for patient selection to avoid post-LASIK keratectasia.

Salzmann's nodular degeneration

Salzmann nodular corneal degeneration is a non-inflammatory, progressive corneal degeneration characterized by bluish-white nodules of varying shapes classically located in the mid-peripheral cornea. It was first described by Maximilian Salzmann in 1925 and was noted at that time to be associated with "eczematous keratoconjunctivitis". Since then, significant progress has been made to understand environmental and genetic risk factors associated with SND. However, etiopathogenesis remains poorly understood. A review of the literature was performed to highlight our recent understanding of SND and its management.

Superficial keratectomy followed by intense pulsed light for Salzmann's nodular degeneration and coexisting meibomian gland dysfunction

PURPOSE

To describe the clinical course of a case of bilateral Salzmann nodular degeneration (SND) treated with superficial keratectomy (SK) followed by intense pulsed light (IPL) for the treatment of coexisting meibomian gland dysfunction (MGD).

CASE DESCRIPTION

A 54-year-old man who presented to us complaining of progressive blurred vision associated with foreign body sensation in both eyes because of SND and coexisting MGD. In view of symptoms and visual acuity (VA) deterioration, bilateral SK was performed. Two months after SK, IPL treatment to the face and meibomian gland expression (MGX) using the E-eye device (E-SWIN, Paris) on days 0, 15, and 45, were performed in both eyes with the aim to avoid recurrence and/or progression of MGD. One year after SK, the patient was asymptomatic and VA was 20/20 in both eyes; however because of worsening of non-invasive tear film break-up time measured on Sirius^® Scheimpflug tomograph, IPL and MGX were promptly repeated and scheduled every 6 months.

CONCLUSION

In our case, IPL was a safe and effective option to control MGD in a patient with SND requiring SK with no observed recurrence of SND 2 years after surgery.