Devarsh Joshi

Introduction

Purtscher retinopathy is an uncommon occlusive retinal microangiopathy that many clinicians will rarely encounter, but it is important because of what it can represent. It was first described by Otmar Purtscher in 1910 in patients who developed retinal haemorrhages and retinal whitening after head trauma (1). Since then, similar retinal findings have been reported in several non-traumatic systemic illnesses. These cases are usually described as Purtscher-like retinopathy.

Purtscher retinopathy classically follows trauma, whereas Purtscher-like retinopathy has been associated with acute pancreatitis, systemic lupus erythematosus, renal disease, childbirth, fat embolism and thrombotic microangiopathy (2–5). In both forms, patients may present with sudden visual loss and characteristic posterior pole changes.

Although rare, the diagnosis matters. In Purtscher-like presentations, the retinal findings may be the first clue to a more serious systemic process. Equally, visual symptoms may be missed when a patient is already acutely unwell with trauma, pancreatitis or renal disease. Purtscher retinopathy is therefore a useful reminder that the retina can provide visible evidence of systemic microvascular injury.

Epidemiology

The true incidence of Purtscher retinopathy is difficult to define. Most published evidence comes from case reports, small case series and retrospective reviews. A UK surveillance study estimated an annual incidence of approximately 0.24 cases per million population, although this is likely to underestimate milder or asymptomatic cases (3).

Trauma remains the classic association, particularly head injury, chest compression and long-bone fractures (2,3). However, Purtscher-like retinopathy is broader and can occur without any traumatic event. In a 2024 systematic review of 168 cases, trauma was the most frequently reported association, followed by systemic lupus erythematosus and acute pancreatitis (5). Bilateral involvement is common, although unilateral cases are also well described (4,5).

This rarity creates a practical problem. Many clinicians may only see one case, if any, during their career. As a result, the diagnosis may not be considered immediately, particularly when the patient’s systemic illness is the main focus of care.

Pathophysiology

The exact mechanism is not fully understood, but Purtscher and Purtscher-like retinopathies are generally considered forms of occlusive retinal microangiopathy (2). The leading theory is that retinal precapillary arterioles become occluded, causing areas of inner retinal ischaemia. Proposed mechanisms include complement activation, leukocyte aggregation, endothelial injury and embolisation by fat, fibrin or platelet aggregates (2,4,5).

This helps explain why very different systemic events can produce a similar retinal appearance. In trauma, vascular injury or embolic material may contribute. In acute pancreatitis, complement activation and leukocyte aggregation have been proposed. In autoimmune disease, inflammatory vascular injury or thrombotic microangiopathy may be involved (2,4,5).

The final common pathway is reduced perfusion of the retinal microcirculation, particularly around the posterior pole. Purtscher flecken are thought to represent areas of inner retinal whitening from microvascular infarction. Cotton-wool spots reflect focal nerve fibre layer ischaemia, while intraretinal haemorrhages suggest associated capillary damage (2,3). These signs are therefore visible evidence of acute retinal vascular compromise.

Clinical Presentation

Patients usually present with sudden, painless visual loss. This may affect one or both eyes, and the severity can vary considerably. Some patients report mild blurring, while others have profound loss of central vision (2–5). Symptoms may include central or paracentral scotomas, reduced contrast sensitivity, difficulty reading, or a general sense that the central field is blurred.

On fundus examination, typical findings include Purtscher flecken, cotton-wool spots, intraretinal haemorrhages and retinal whitening. Optic disc swelling and macular oedema may also be present (2–5). The posterior pole is usually most affected, which explains why central visual symptoms are common. In the 2024 systematic review, cotton-wool spots were the most commonly reported retinal finding, followed by Purtscher flecken (5).

One reason the diagnosis can be missed is that the visual complaint may not be the most obvious part of the presentation. A patient admitted after major trauma, or with pancreatitis or renal failure, may not volunteer visual symptoms unless asked directly. In that context, a simple question about new blurring, distortion or scotoma can be clinically valuable.

Diagnosis

Diagnosis is mainly clinical. A commonly cited diagnostic approach requires at least three of the following: Purtscher flecken, a low-to-moderate number of retinal haemorrhages, cotton-wool spots typically restricted to the posterior pole, a plausible associated cause, and compatible complementary investigation findings (4). These criteria are helpful, but they should be applied alongside clinical judgement, particularly because Purtscher flecken are characteristic but not present in every case (4,5).

Retinal imaging can help assess the extent of disease. Fundus fluorescein angiography may show capillary non-perfusion, vascular leakage or delayed filling, supporting the concept of retinal microvascular occlusion (2,4). Optical coherence tomography can show inner retinal hyperreflectivity and thickening in the acute phase, with later thinning or atrophic change in more severe cases (6). OCT angiography may demonstrate capillary flow deficits (6). These investigations are useful adjuncts, although diagnosis remains primarily clinical (2,4).

The differential diagnosis includes central retinal artery occlusion, branch retinal artery occlusion, central retinal vein occlusion, diabetic retinopathy, hypertensive retinopathy, commotio retinae and fat embolism syndrome (2,4). In Purtscher-like cases, the systemic work-up should be guided by the clinical context. Depending on the presentation, this may include assessment for pancreatitis, autoimmune disease, renal impairment, haematological disorders or thrombotic microangiopathy.

Management

There is no universally accepted ocular treatment for Purtscher or Purtscher-like retinopathy. Suspected cases should prompt ophthalmology assessment, retinal imaging where available, and consideration of the underlying systemic trigger. Management is mainly directed at the underlying cause (2,4,7). In trauma-associated cases, this may involve observation and supportive care. In Purtscher-like retinopathy, management depends on the precipitating condition, such as pancreatitis, systemic lupus erythematosus, renal disease or a thrombotic process.

Systemic corticosteroids have been used in some cases, particularly where inflammatory or complement-mediated injury is suspected. However, the evidence is limited. A systematic review of treatment outcomes found that visual improvement can occur with or without treatment, and current evidence does not clearly demonstrate a benefit of glucocorticoids over observation (7). Steroids should therefore be described as a possible treatment in selected cases, not as routine therapy.

Follow-up is important. Even when the acute fundus signs improve, patients may be left with persistent scotomas, reduced contrast sensitivity or structural retinal change. Patients should therefore be counselled that visual recovery is possible, but not guaranteed.

Prognosis

Visual prognosis is variable. Some patients recover useful vision over weeks to months, particularly if retinal ischaemia is limited and the systemic trigger is controlled (2–5,7). In the UK surveillance study, around half of affected eyes improved by at least two Snellen lines without treatment (3). However, others may have persistent visual impairment, especially when the macula is involved or there is extensive capillary non-perfusion.

Long-term changes can include optic disc pallor, retinal pigmentary change, retinal thinning and persistent central or paracentral scotomas (2,4,6). The condition should therefore not be dismissed as benign, even though spontaneous improvement can occur. Prognosis depends on both the degree of retinal involvement and the severity of the underlying systemic disease.

Conclusion

Purtscher and Purtscher-like retinopathies are rare retinal microvascular disorders that can present with sudden visual loss and characteristic posterior pole findings. Recognising the condition is important because it may point towards significant systemic disease, particularly in Purtscher-like cases. Diagnosis is primarily clinical, supported by retinal imaging and careful systemic assessment. There is no proven universal ocular treatment, so management should focus on the underlying cause, appropriate follow-up and realistic counselling about visual recovery.

References

1. Purtscher O. Noch unbekannte Befunde nach Schädeltrauma. Ber Dtsch Ophthalmol Ges. 1910;36:294–301.
2. Agrawal A, McKibbin MA. Purtscher’s and Purtscher-like retinopathies: a review. Surv Ophthalmol. 2006;51(2):129–136. doi:10.1016/j.survophthal.2005.12.003.
3. Agrawal A, McKibbin M. Purtscher’s retinopathy: epidemiology, clinical features and outcome. Br J Ophthalmol. 2007;91(11):1456–1459. doi:10.1136/bjo.2007.117408.
4. Miguel AIM, Henriques F, Azevedo LFR, Loureiro AJR, Maberley DAL. Systematic review of Purtscher’s and Purtscher-like retinopathies. Eye (Lond). 2013;27(1):1–13. doi:10.1038/eye.2012.222.
5. Serhan HA, Abuawwad MT, Taha MJJ, Hassan AK, Abu-Ismail L, Delsoz M, et al. Purtscher’s and Purtscher-like retinopathy etiology, features, management, and outcomes: a summative systematic review of 168 cases. PLoS One. 2024;19(9):e0306473. doi:10.1371/journal.pone.0306473.
6. Xiao W, He L, Mao Y, Yang H. Multimodal imaging in Purtscher retinopathy. Retina. 2018;38(7):e59–e60. doi:10.1097/IAE.0000000000002218.
7. Xia D, Chen X, Zhou Q, Xiao S, Yu Y, Wang Y, et al. Efficacy of Purtscher’s retinopathy treatments: a systematic review. Curr Eye Res. 2017;42(6):908–917. doi:10.1080/02713683.2016.1255335.