Blurred vision after cataract surgery: is it normal?

Yes, blurred vision in the hours and first days after cataract surgery is usual. Vision then clears gradually. What should raise an alarm is vision that drops suddenly, that becomes distorted, or that comes with pain, a red eye or a black curtain.

KEY POINTS

FIRST FEW DAYS

Blurring in the first hours and days

On leaving the clinic, vision is blurred, the eye stings and feels as if there were a grain of sand in it: this is usual, partly because of the antiseptic applied before the operation. These surface sensations are described in the discomfort and gritty feeling after the operation. As for the blurring itself, three mechanisms add up.

• The pupil stays dilated until the effect of the morning’s eye drops wears off: light dazzles and focusing is imprecise;
• The cornea may be slightly swollen (corneal oedema): vision looks veiled, as if through condensation, then clears;
• The surface of the eye is irritated: the tear film is unstable, and vision fluctuates from one blink to the next.

Corneal oedema

The cornea is the clear window in front of the iris. Its transparency depends on a thin layer of cells, the endothelium, which constantly pumps out the water held in the tissue. The ultrasound that breaks up the lens puts this layer under strain: a systematic review of 103 studies directly links corneal oedema after cataract surgery to the loss of endothelial cells during the operation, made more likely by age, the hardness of the cataract and the mechanical stresses of the procedure Briceno-Lopez 2023. The cornea then retains a little water and thickens: vision becomes milky, often with halos around lights in the evening.

This oedema is usually transient. It is more marked, and takes longer to clear, when the endothelium was already fragile before the operation. This is the case with Fuchs dystrophy, seen in about 4% of people over 40, which puts the cornea at risk of decompensation after surgery Moshirfar 2022. This fragility is looked for with the slit lamp before the operation; when a cell count is needed, it is requested at a specialist centre. The eye drops on your prescription are prescribed for one month: you do not stop them because vision has cleared.

What is expected, and what is not

Expected in the first few days: veiled or milky vision that clears from one day to the next, dazzle in bright light, a watering eye, a pinkish white of the eye, vision that fluctuates with blinking.

Not expected: vision that darkens or clearly drops from one hour to the next, pain that increases and is not relieved by paracetamol, a red, painful eye, a black curtain or flashes. These signs call for the emergency procedure described further down.

Do not touch the eye and do not change the prescription: the first check-up takes place two days after the operation, the next at one month, then at one year. This timetable is covered in full in recovery after cataract surgery, and the things to avoid in what not to do after the operation.

FIRST FEW WEEKS

Blurring in the first few weeks

A correction that is not yet the right one

A small residual optical error is common, and a monofocal implant set for distance vision leaves reading blurred without glasses. The result to expect without correction depends on the implant chosen: see choosing the implant.

Your old glasses, for their part, no longer match the operated eye and keep the blurring going. New ones are prescribed 3 to 4 weeks after the operation and, if both eyes are operated on, 3 to 4 weeks after the second. On the administrative side, the French ministerial order (arrêté) of 3 December 2018 lists “cataract surgery less than 1 year old” among the situations in which the renewal of lenses is subject to no minimum interval, on a new prescription from the ophthalmologist. The subject is covered in detail in glasses after cataract surgery.

Dry eye

Vision that blurs at the screen or at the end of the day, then becomes sharp again after a few blinks, suggests dryness. It is common: in a meta-analysis of nine studies, 37.4% of patients who had no dry eye before the operation developed it afterwards. The discomfort is at its worst the day after the operation and can last from one month to a year Miura 2022. This is what the artificial tears on the prescription are for, to be continued for as long as the discomfort lasts. See dry eye.

Two eyes that are not yet in step

Between the two operations, spaced 1 to 2 weeks apart, one eye sees with its implant and the other with its cataract and its old correction. Hence an impression of imbalance, difficulty judging distances and visual fatigue, which ease off after the second eye is operated on. Night-time halos and glare, for their part, are covered in EDOF implants and night-time halos.

SOME TIME LATER

A blur that appears afterwards, distorted vision: macular oedema

Vision had recovered well, then it worsens again or stops improving: this may be post-operative macular oedema, also called Irvine-Gass syndrome. The centre of the retina, the macula, thickens as a result of the inflammation that follows the operation. It generally occurs around six weeks after the operation, and the risk is doubled in people with diabetes Fouad 2025.

One sign points to the macula: straight lines that wave (the edge of a door, the lines of a text) or a blurred spot at the centre. A blur that is improving can wait for the scheduled check-up; vision that worsens again or becomes distorted should be reported to the practice.

Diagnosis rests on OCT, a non-contact retinal imaging examination, available at the Cachan practice. According to the review by Fouad (2025), management is graded: monitoring when the discomfort is minimal, anti-inflammatory eye drops when it is real, and corticosteroid injections around the eye or into the eye for forms that resist. The same review points out that a history of macular oedema in the first eye is probably the strongest risk factor for the second: this is useful information to give before the operation on the other side.

MONTHS OR YEARS AFTER

Blurring that returns long afterwards: secondary cataract

A cataract does not “grow back”: the lens that has been removed never re-forms. On the other hand, the thin envelope that supports the implant, the capsule, can become opaque with time. This capsular opacification is a frequent and well-known development after this surgery Milazzo 2014.

The picture closely resembles that of the original cataract, and this is what troubles patients: a veil that sets in slowly over months, growing discomfort against the light and when facing headlights, the impression that glasses are no longer strong enough. The difference lies in the timeline: recovery after the operation had taken place, and it is from that vision that you are going back down.

The treatment is the YAG laser, which opens the opacified capsule in a few minutes, without an incision and without a hospital stay. The procedure is not trivial for all that: the review by Milazzo (2014) recalls that opening the capsule can lead to complications and that prevention remains the main way of limiting this development. In practice, the opening made is long-lasting: in most cases the procedure does not need to be repeated. Indications, course and precautions are described on the page secondary cataract and YAG laser.

EMERGENCY

When blurred vision is an emergency

What these signs make us look for

Their presence does not mean that a complication has set in. It does, however, make it necessary to rule out situations that cannot wait for the next check-up:

• an infection inside the eye (endophthalmitis): rare, it most often shows itself in the first few days as a rapid drop in vision, increasing pain and a red eye;
• a rise in the pressure inside the eye, which combines veiled vision, halos and pain;
• a retinal detachment, suggested by a black curtain that spreads, flashes or a sudden shower of black dots;
• more rarely, a cornea that does not regain its transparency after the operation.

When in doubt, it is better to phone for nothing than to let a day go by. The page eye emergencies details what to do.

IN SUMMARY

When, why, what to do: the summary

FREQUENTLY ASKED QUESTIONS

Frequently asked questions

SOURCES

Scientific sources

1. Fouad YA, Karimaghaei S, Elhusseiny AM, Alagorie AR, et al. Pseudophakic cystoid macular edema. Curr Opin Ophthalmol. 2025;36(1):62-69. PMID: 39446879
2. Briceno-Lopez C, Burguera-Giménez N, García-Domene MC, Díez-Ajenjo MA, et al. Corneal Edema after Cataract Surgery. J Clin Med. 2023;12(21):6751. PMID: 37959216
3. Moshirfar M, Huynh R, Ellis JH. Cataract surgery and intraocular lens placement in patients with Fuchs corneal dystrophy: a review of the current literature. Curr Opin Ophthalmol. 2022;33(1):21-27. PMID: 34743088
4. Miura M, Inomata T, Nakamura M, Sung J, et al. Prevalence and Characteristics of Dry Eye Disease After Cataract Surgery: A Systematic Review and Meta-Analysis. Ophthalmol Ther. 2022;11(4):1309-1332. PMID: 35534685
5. Milazzo S, Grenot M, Benzerroug M. [Posterior capsule opacification]. J Fr Ophtalmol. 2014;37(10):825-830. PMID: 25455552

GOING FURTHER

Further reading

• Recovery after cataract surgery: the complete timeline
• Recovery after the operation: how long does it take?
• Eye pain one month after the operation

Cachan practice · Tel. +33 1 45 47 08 11

MEDICAL DISCLAIMER

Medical disclaimer

This article is intended as general information and does not replace a medical consultation. After cataract surgery, any drop in vision that worries you warrants an ophthalmological examination; if there is a warning sign, consult without delay.

The time frames given here describe a usual course of events: they do not prejudge your situation, which depends on the hardness of the cataract, the state of the cornea and the retina, and the treatments under way. The figures quoted come from the publications listed above and relate to study populations, not to any individual patient. The check-up schedule, the duration of the eye drops and the timing of the new glasses prescription are those of the practice; they may be changed by the surgeon according to how your operation and your recovery go.