Failure to Diagnose Aneurysm Injury Attorney: When a Missed Diagnosis Becomes Medical Malpractice

Last updated: October 22, 2026

You may be able to sue in New York if a doctor or hospital missed the warning signs of a brain or aortic aneurysm and the aneurysm then ruptured or bled again, causing injury or death that timely treatment would likely have prevented. A common example is a sudden “worst headache of my life” sent home without a CT scan. A failure to diagnose an aneurysm injury attorney proves this with the ER records, a re-read of the imaging, and expert testimony. Most New York claims must be filed within 2 years and 6 months (CPLR 214-a). Public hospital and wrongful death claims have shorter deadlines, and New Jersey, Pennsylvania, and Connecticut have their own rules.

It was written by the medical malpractice team at Kramer, Dillof, Livingston & Moore (KDLM), a Manhattan personal injury firm, for patients and their families. It is general information, not legal advice about a specific case.

Can you sue a doctor for a wrong or late diagnosis?

Yes. In New York, you can bring a medical malpractice lawsuit when a doctor or other healthcare provider did not meet the accepted standard of care and that negligence caused serious harm. A bad outcome by itself is not enough. The question is whether a reasonably prudent doctor would have caught the problem, and whether catching it sooner would have changed the result.

Every malpractice claim needs three things:

• A departure from accepted medical practice: for example, sending home a patient with the “worst headache of my life” without a CT scan, misreading a scan, or ignoring an abnormal finding.
• Causation: proof that an accurate diagnosis in time would likely have led to treatment, such as surgical clipping or endovascular coiling, before the artery burst or bled again.
• Damages: the injuries and losses that followed.

New York requires the lawyer to consult a physician and certify that the case has merit before filing (CPLR 3012-a). These cases rely on evidence and expert testimony from emergency physicians, neurosurgeons, vascular surgeons and a radiologist who can reread the original images.

Why are aneurysms so often a missed diagnosis?

Because they are silent until they are not. A brain (cerebral) aneurysm is a weak, bulging spot in an artery wall. Most cause no symptoms until they leak or rupture, and the early signs look like everyday complaints.

The Brain Aneurysm Foundation estimates that about 6.8 million people in the United States, roughly 1 in 50, have an unruptured bulge in a brain artery, that about 30,000 ruptures happen each year, and that about half of ruptures are fatal.

A study of 482 patients with subarachnoid hemorrhage (bleeding around the brain) published in JAMA in 2004 found that 12% were misdiagnosed at their first visit. Migraine or tension headache was the most common wrong diagnosis, and failure to obtain a CT scan was the most common error. In patients who were alert at that first visit, the delay in diagnosis was linked to a higher risk of severe disability or death (Kowalski et al., JAMA, 2004;291:866-869).

Which warning signs should a medical professional not ignore?

• A “thunderclap” headache: sudden and severe, often the worst headache of the patient’s life.
• A sentinel headache: a warning headache from a small leak that can come days or weeks before a major rupture, according to the National Institute of Neurological Disorders and Stroke.
• Stiff neck, vomiting, light sensitivity, double vision or brief loss of consciousness.
• Pain behind an eye, a dilated pupil, or vision changes, which can signal a growing bulge pressing on a nerve.
• Sudden belly, back, or flank pain with dizziness or low blood pressure, which can signal a rupturing abdominal aortic aneurysm (AAA) mistaken for kidney stones or back strain.

If a CT is negative but suspicion remains, guidelines often call for a lumbar puncture or CT angiography. For the aorta, the U.S. Preventive Services Task Force recommends one-time ultrasound screening in men aged 65 to 75 who have ever smoked. When doctors miss these signs, or a known bulge goes untreated, a treatable condition can become an emergency.

What injuries can delayed diagnoses cause?

A missed bleed can lead to stroke, permanent injury or death, and the harm is often worse when a first bleed is followed by a second.

• Re-bleeding: a second rupture, which sharply worsens the outlook.
• Brain damage: from bleeding, vasospasm (narrowed arteries that cut off blood to the brain) or hydrocephalus (fluid build-up).
• Paralysis, speech loss, and memory problems.
• Internal bleeding from a ruptured aorta, which is often fatal.

Many brain injuries caused by medical delay are preventable. Compensation may include medical costs, future medical care, lost earnings, and pain and suffering. If a loved one suffered a fatal rupture, the estate’s personal representative (usually a family member) brings the wrongful death claim on behalf of the family. New York does not cap damages in medical malpractice cases, but no lawyer can honestly promise maximum compensation or any particular outcome.

Can I sue a hospital for misdiagnosis?

Yes. A hospital may be liable for a medical misdiagnosis by its employees, including emergency doctors, nurses, and staff radiologists, and sometimes for its own medical errors, such as poor systems for reporting critical test results.

Claims against public hospitals, including NYC Health + Hospitals facilities, generally require a notice of claim within 90 days, and the lawsuit generally must be started within 1 year and 90 days. Identifying every potentially negligent healthcare provider early protects your claim.

How long do you have to file a malpractice claim in New York?

In most cases, you have 2 years and 6 months from the malpractice, or from the end of continuous treatment, to file (CPLR 214-a). A wrongful death action generally must be filed within 2 years of death (EPTL 5-4.1). Lavern’s Law, which can delay the start of the clock, applies only to a failure to diagnose cancer. Learn more in our guide to the New York medical malpractice statute of limitations.

What are the deadlines and rules in NY, NJ, PA and CT?

Aneurysm patients are often seen at an ER near home or work, which may be outside New York. KDLM handles cases in New York, New Jersey, Pennsylvania, and Connecticut, and each state sets its own deadlines and filing rules. This is a general summary of the law as of October 22, 2026, not legal advice. Exceptions can shorten or extend these periods, so have a lawyer confirm the dates for your case.

New York

• Deadline: 2 years and 6 months from the malpractice, or from the last treatment if you kept treating with the same provider for the same condition (CPLR 214-a). Missed cancer: 2 years and 6 months from when you knew or should have known of the error and the harm, but no more than 7 years from the error (Lavern’s Law). Foreign object left in the body: 1 year from discovery.
• Children: the clock is paused until age 18, but a malpractice claim can’t be extended more than 10 years past the malpractice (CPLR 208).
• Merit rule: the lawyer files a certificate of merit with the complaint after consulting a physician (CPLR 3012-a).
• Wrongful death: 2 years from death (EPTL 5-4.1); damages are limited to financial losses (EPTL 5-4.3).
• Damages and fault: no cap on malpractice damages. A patient’s own share of fault reduces the award but doesn’t bar it (CPLR 1411).
• Public hospitals: notice of claim generally within 90 days, and suit within 1 year and 90 days (General Municipal Law 50-e and 50-i; NYC Health + Hospitals).

New Jersey

• Deadline: 2 years (N.J.S.A. 2A:14-2). Courts apply a discovery rule, so the clock can start when you knew or should have known of the injury and its likely cause.
• Children: injuries at birth must be filed before the child’s 13th birthday (N.J.S.A. 2A:14-2). For other injuries, the clock is generally paused until age 18 (N.J.S.A. 2A:14-21).
• Merit rule: an affidavit of merit from an appropriate licensed professional is due within 60 days after the defendant answers. A court can allow one extra period of up to 60 days (N.J.S.A. 2A:53A-27).
• Wrongful death: 2 years from death (N.J.S.A. 2A:31-3).
• Damages and fault: no general cap, but a nonprofit hospital’s liability is capped at $250,000 (N.J.S.A. 2A:53A-8). A patient whose fault is greater than the defendants’ recovers nothing (N.J.S.A. 2A:15-5.1).
• Public hospitals: Tort Claims Act notice within 90 days. Suit can be filed after 6 months and within 2 years (N.J.S.A. 59:8-8).

Pennsylvania

• Deadline: 2 years (42 Pa.C.S. 5524), with a court-made discovery rule. The 7-year outer limit in the MCARE Act was struck down by the Pennsylvania Supreme Court in Yanakos v. UPMC (2019).
• Children: the clock is paused until age 18, and then the normal 2 years runs (42 Pa.C.S. 5533(b)).
• Merit rule: a certificate of merit for each licensed professional is filed with the complaint or within 60 days after it (Pa.R.C.P. 1042.3).
• Wrongful death: wrongful death and survival claims based on malpractice must be filed within 2 years of death, unless the cause of death was misrepresented or concealed (40 P.S. 1303.513(d)).
• Damages and fault: no cap on compensatory damages. Punitive damages against an individual doctor are generally limited to 200% of compensatory damages (40 P.S. 1303.505). A patient whose fault is greater than the defendant’s recovers nothing (42 Pa.C.S. 7102).
• Public hospitals: written notice to the government unit within 6 months (42 Pa.C.S. 5522). Damages against Commonwealth parties are capped at $250,000 per plaintiff (42 Pa.C.S. 8528), and against local agencies at $500,000 in total (42 Pa.C.S. 8553).

Connecticut

• Deadline: 2 years from when the injury was sustained or discovered (or should have been), and never more than 3 years from the act or omission (C.G.S. 52-584). Continuing-treatment and continuing-conduct doctrines can pause the clock. An automatic 90-day extension is available by petition (C.G.S. 52-190a(b)).
• Children: the malpractice statute has no general extension for minors, so the same limits usually apply to a child’s claim.
• Merit rule: the complaint must include a good-faith certificate and a written, signed opinion from a similar health care provider. Without the opinion letter, the case can be dismissed (C.G.S. 52-190a).
• Wrongful death: 2 years from death, and no more than 5 years from the act or omission (C.G.S. 52-555).
• Damages and fault: no cap on malpractice damages. A patient whose fault is greater than the defendants’ combined fault recovers nothing (C.G.S. 52-572h).
• State hospitals: claims against the state generally have to be presented within 1 year, and never more than 3 years from the act (C.G.S. 4-148). A malpractice suit can be filed directly within that period with a good-faith certificate (C.G.S. 4-160(f)).

The outcome: if your care happened outside New York, the deadline may be shorter, and the merit paperwork is different. Ask early so nothing is missed.

What should you do if you think a diagnosis was missed?

1. Get the care you need first, and seek a second opinion from a specialist about diagnosis and treatment options.
2. Request copies of emergency room, imaging, and discharge records.
3. Write down a timeline: when symptoms started, who you saw, and what you were told.
4. Talk to a medical malpractice lawyer who can review medical records with qualified medical experts.

Why choose our law firm for a failure to diagnose case?

An injury caused by a doctor’s misdiagnosis needs an experienced medical malpractice attorney who can master the medicine and take the case to trial if the insurer will not pay fair value.

KDLM has represented victims and their families in medical negligence cases for decades. The firm’s verdicts and settlements include a $108 million verdict in a case involving undiagnosed meningitis, and our recap of misdiagnosis cases lists results across many conditions. Past results do not guarantee a similar outcome.

We also handle complex medical malpractice cases involving cancer, stroke, and birth injury. Read about missed stroke cases, cancer misdiagnosis settlements, or how a failure to diagnose lawsuit works in New York.

Frequently asked questions

Can you sue a doctor for missing an aneurysm?

Yes, if the doctor departed from accepted practice, for example, by not ordering a CT scan for a sudden severe headache, and the delay caused harm such as a rupture or re-bleed. New York requires a physician review and a certificate of merit before filing.

How long do I have to sue for a missed aneurysm in New York?

Generally, 2 years and 6 months from the malpractice, or from the end of continuous treatment (CPLR 214-a). Public hospital claims usually require a notice of claim within 90 days and a lawsuit within 1 year and 90 days, and a wrongful death action generally must be filed within 2 years of death.

Should a doctor have caught my sentinel headache?

Not always, but a sudden severe headache is a recognized warning sign. NINDS notes that a sentinel headache can come days or weeks before a major rupture. Whether imaging was needed depends on the symptoms and history, which is why an expert review matters.

How much is a misdiagnosis case worth?

There is no average figure. Value depends on the injury, the effect on the patient’s life and earnings, future care needs, and the strength of the evidence.

Can I sue if the problem was found but not treated in time?

Possibly. A failure to treat, such as not referring a known bulge to a specialist or not monitoring its growth, can be malpractice if it fell below the standard of care and caused harm.

Who can bring a claim if the patient died?

The personal representative of the estate brings a wrongful death claim for the family, generally within 2 years of death, along with a claim for the patient’s conscious pain before death.

Does the deadline differ outside New York?

Yes. New Jersey and Pennsylvania generally allow 2 years, and their courts apply a discovery rule. Connecticut allows 2 years from when the injury was or should have been discovered, but no more than 3 years from the error. Each state also has its own merit filing: a New Jersey affidavit of merit, a Pennsylvania certificate of merit, or a Connecticut opinion letter. Wrongful death deadlines and public-hospital notice rules also differ. KDLM handles cases in all four states, so contact us early to have your dates checked.

Get a free consultation with a misdiagnosis attorney

KDLM represents patients throughout New York and works on a contingent fee: no fee unless we win. Call (212) 618-6800 for a free consultation.