Posterior Vitreous Detachment (PVD) is a relatively common ophthalmic condition that most doctors will encounter in general practice, the emergency department, or ophthalmology referrals (1). Although it is often benign, it can present with symptoms also seen in more serious conditions and so being able to accurately recognise and triage patients is essential.

This article aims to provide medical students and resident doctors with a foundational understanding. It will explore the pathophysiology of the condition, how it presents, its complications and management.

What is Posterior Vitreous Detachment?

The vitreous humour is the gel-like substance which fills the posterior segment of the eye, maintaining its shape and helping transmit light to the retina. As people age, the vitreous undergoes a process called syneresis, where it becomes more liquid and contracts (2).

This process can lead to the separation of the posterior vitreous cortex from the underlying neurosensory retina, which is known as Posterior Vitreous Detachment. It’s a natural, age-related change and occurs in up to 65% of individuals by the time they reach the age of 65 (3)

https://www.allaboutvision.com/conditions/posterior-vitreous-detachment/ Accessed 02/06/25

Risk Factors

While PVD is most commonly age-related, there are certain factors which can predispose patients to earlier or symptomatic detachment (4,5):

• Myopia (especially high myopia): Longer axial length increases traction.
• Previous vitreoretinal surgery
• Ocular trauma
• Cataract surgery (especially phacoemulsification)
• Inflammatory eye conditions (e.g., uveitis)
• Diabetes mellitus

Clinical Presentation

The typical patient is over the age of 50, and will present with one or more of (4):

• Floaters: Patients will describe this as cobwebs, flies, or threads moving in their visual field.
• Flashes (photopsia): Spark-like flashes of light, especially in their peripheral vision.
• Visual obstructions: Sometimes a Weiss ring (a circular floater caused by detachment of the vitreous from the optic disc) is reported in patients

These symptoms tend to occur due to vitreoretinal traction and the shifting of collagen fibrils within the vitreous cavity where it detaches. Most of these symptoms tend to settle over several weeks as the vitreous stabilises and the visual obstructions become less noticeable.

Red Flags and Retinal Tears

While PVD itself is benign, it can lead to breaks within the retina such as retinal tears, which can progress to retinal detachment. Retina tears have been reported in 10-15% of symptomatic cases (6). Hence, it is essential to identify red flags, which necessitate an urgent ophthalmology referral. These are:

• A sudden onset of many floaters, or sudden worsening in patients with longstanding floaters
• Persistent or increasing flashes
• Loss of part of the visual field (fixed shadow or dark curtain), which suggests retinal detachment
• Decreased visual acuity
• Recent eye surgery or trauma
• High myopia, previous history of retinal detachment or family history of retinal detachment
• Symptoms starting after eye trauma

Retinal detachment is a sight-threatening emergency and typically requires urgent surgical management.

Examination – What can you do as a Resident doctor?

While the definitive diagnosis will require a slit-lamp biomicroscopy and fundoscopy by an ophthalmologist, an F1 or ED doctor can still heavily contribute:

1. Take a focused history:
   • Assess the timing and character of symptoms
   • Check if there is any associated trauma
   • Assess for the presence of field loss or visual acuity reduction
2. Check visual acuity:
   • Use a Snellen chart at 6 metres
   • Check pinhole vision if acuity is reduced
3. Confrontation visual fields:
   • Check for peripheral visual field loss (this may not detect peripheral field loss reliably – a formal assessment is needed in suspected retinal detachment).
4. Pupil reactions:
   • Rule out a relative afferent pupillary defect (RAPD)
   • RAPD suggests possible retinal detachment, or optic nerve involvement.
5. Fundoscopy (if trained/confident):
   • A Weiss ring may be visible
   • Vitreous haemorrhage increases the likelihood of a retinal tear

Diagnosis and Referral

If PVD is uncomplicated, patients can be reassured and be followed up by the Ophthalmology department as an outpatient. However, if there are any red flag symptoms present, a same-day urgent referral to ophthalmology is essential. The Royal College of Ophthalmologists advises that any new onset of flashes and floaters should be assessed within 24 hours (7).

The Ophthalmology department will typically assess the patient through:

• Slit-lamp biomicroscopy and fundoscopy with a 90D lens and Goldmann lens
• Indirect ophthalmoscopy with scleral indentation
• Ocular ultrasound
• Sometimes optical coherence tomography (OCT) and wide-field retinal imaging

Management

In most cases, no treatment is required for uncomplicated PVD. However, patients should be advised that:

• Symptoms will usually improve over 4-12 weeks
• To return immediately if they notice:
  • A worsening of their floaters or flashes
  • Visual field loss (“dark curtain” coming down)
  • Blurred vision

If a retinal tear is identified, then laser retinopexy or cryotherapy may be used to prevent detachment. If a retinal detachment has been diagnosed, then the patient requires vitrectomy or scleral buckling surgery.

Take-Home Points

• Posterior Vitreous Detachment (PVD) is a common condition, especially in older adults.
• Floaters and flashes are typical symptoms of PVD – it is important to ask about field loss or visual acuity.
• Always rule out the presence of a retinal tear or detachment.
• Know the red flag symptoms: refer urgently if in doubt.
• Most cases are benign, but missing a retinal tear can lead to blindness.

References

• Yonemoto, J; Noda, Y; Masuhara, N; Ohno, S (June 1996). “Age of onset of posterior vitreous detachment”. Current Opinion in Ophthalmology. 7 (3): 73–6. doi:10.1097/00055735-199606000-00012. PMID 10163464.
• Gauger E; Chin EK; Sohn EH (17 November 2014). “Vitreous Syneresis: An Impending Posterior Vitreous Detachment (PVD)”. University of Iowa Health Care: Ophthalmology and Visual Sciences; See “Discussion” following “Clinical Course”.
• Syed Z, Stewart M. Age-dependent vitreous separation from the macula in a clinic population. Clin Ophthalmol. 2016;10:1237-43.
• Ahmed F, Tripathy K. Posterior Vitreous Detachment. [Updated 2023 Aug 25]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2025 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK563273/
• https://eyewiki.org/Posterior_Vitreous_Detachment
• Hollands H, Johnson D, Brox AC, et al. Acute-onset floaters and flashes: is this patient at risk for retinal detachment? JAMA. 2009;302(20):2243–2249.
• The Royal College of Ophthalmologists. Emergency Eye Care Guidance. Updated July 2021. Available: https://rcophth.ac.uk

Written by Dr Michael Milad, FY1, West Hertfordshire NHS Trust & Reviewed by Miss Marcela Bohn, Medical Retina and Uveitis Consultant