Changing Patterns of Ultrasound-Related Litigation

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1 Commemoration Changing Patterns of Ultrasound-Related Litigation A Historical Survey Roger C. Sanders, MD Los Alamos Women s Health Center Los Alamos Medical Center Los Alamos, New Mexico USA Abbreviations IUD, intrauterine device; IUGR, intrauterine growth restriction The earliest litigation related to diagnostic ultrasound that I am aware of dates to 1974 and involved obstetric measurements. Before 1974, images were so difficult to interpret that ultrasound was considered of little value apart from obstetric measurement data and for characterizing masses as cysts (Fig. 1). Gray scale sonography came in 1974, and, abruptly, referrals for ultrasound became more widespread as clinicians began to understand the images. With understanding came greatly increased clinical use, and, as night follows day, then came lawsuits. A personal suit for missing a case of spina bifida in 1981 sparked my interest in litigation related to ultrasound. Little information was available because legal monitoring and archiving systems at that time only documented cases that went to court and were not settled out of court ( 98% of cases are settled out of court). A survey of members of the Society of Radiologists in Ultrasound, at that time a select group limited to 50 members who performed ultrasound examinations full time, was conducted. Details of 32 cases were obtained. Meanwhile, Charles W. Hohler, MD, an obstetrician who was involved in ultrasound in the late 1970s and early 1980s, became interested in litigation related to ultrasound. He had access to a survey of 10% of American College of Obstetricians and Gynecologists members, which included 1 question about legal suits related to ultrasound. To our astonishment, this survey yielded crude information about 62 cases. 1 There was obviously a considerable amount of litigation going on. Because about 98% of all medical malpractice cases are settled out of court, this was new information. For the next 19 years, I tracked litigation related to ultrasound by asking for information about cases from expert witnesses, tabulating my own cases, and getting information about cases when I spoke at meetings. During the 6 years that I sat on the American College of Radiology Litigation Committee, I had access to a journal of settled cases in which trial lawyers reported their successful cases. Articles reviewing the series were published 5 times with updated statistics on 4 occasions. 1 5 A comparison of the different case series is shown in the tables below. In the columns labeled 2002 are the cases that I have seen as an expert witness since This group is biased toward obstetric and gynecologic ultrasound because I have not performed abdominal ultrasound since My cases are equally split between plaintiffs and defendants. The tables include information about dropped legal cases, settled 2003 by the American Institute of Ultrasound in Medicine J Ultrasound Med 22: , /03/$3.50

2 Changing Patterns of Ultrasound-Related Litigation Table 1. Cases by Specialty Area Specialty Total Obstetrics Gynecology Abdominal Neonatal intracranial Breast Eye Miscellaneous Total for series Figure 1. Sagittal bistable view of the pelvis, The adnexal mass (M) was erroneously called a cyst, but it was a solid ovarian tumor. Note the relative absence of through-transmission. cases, and cases that ended up in court. Information about case outcomes is sketchy because informants seldom reported on the eventual outcomes of the cases. Some cases had little merit and never got beyond a review by a competent expert witness. When performance and interpretation of the case are within the standard of care, competent experts refuse the case. (The 2002 series includes 11 cases that I reviewed for plaintiff lawyers but refused because I thought the cases had no merit. All had already been filed in court.) A comparison of the tables shows the changes that have occurred in patterns of litigation since I have subdivided the types of litigation into 8 groups: missed diagnoses, misinterpreted sonograms, invented lesions, delay in communicating information to a clinician, failure to perform sonography, fraud cases, procedure-related cases, and sonographer-related suits. I have also grouped them into the area of ultrasound involved. Suits related to obstetric ultrasound (Table 1) have been and continue to be much more common than suits in other areas, such as gynecology and the abdomen. Presumably this relates to a greater use and reliance on ultrasound in obstetrics in this country, more litigation because the financial reward from a damaged infant is large, and greater public awareness of the role of ultrasound in obstetrics. I did not attempt to track suits related to cardiology or fetal echocardiography. It is also likely that many of the suits related to vascular studies or to breast sonography are not included in the series. Litigation related to missed breast cancer is very common but is rarely solely related to the ultrasound study because that study is often used as a backup to the mammogram, so most cases would not be included in the series. Missed diagnoses (Table 2), cases in which an entity was completely overlooked, continue to be the most common type of suit. In 1983, because real-time sonography was only available as a crude additional technique for use with gray scale sonography, and the vaginal probe was not in use, ectopic pregnancy was a very common cause of litigation; in the absence of the vaginal probe and real-time imaging, making the diagnosis was often difficult. Fetal anomalies, now by far the most common causes of this type of litigation, were relatively uncommon in 1983 because the images were relatively crude. Furthermore, missed twins or triplets were relatively frequent before the routine use of real-time sonography. It was easy to assume that the second fetus was simply movement of the fetus into another position. Today, missed diagnoses related to multiple Table 2. Missed Diagnoses Diagnosis Total Ectopic or abdominal pregnancy Fetal anomaly Placenta previa Multiple pregnancy Appendiceal abscess IUGR IUD Gallstones Abruptio placentae Ovarian mass Miscellaneous Total for series J Ultrasound Med 22: , 2003

3 Sanders pregnancies are due to complications of twins, such as a missed stuck twin or twin-twin transfusion syndrome. Placenta previa was quite a common cause of litigation before the introduction of translabial and endovaginal techniques but is a rare problem today. An important group in 1983 comprised invented lesions (Table 3). Images sometimes dating back to bistable days appeared to show lesions, yet with surgery or other intervention, nothing was found. Most of the invented lesions were related to primitive equipment. Fetal death was misdiagnosed because realtime imaging was not available, or the real-time system had very limited ability to show structures at depth. Moles were invented on bistable B-scan views when there was only a large placenta (Fig. 2, A and B). Three invented anencephalic cases were reported because the fetal head was located too deep to see from an abdominal approach. Potter syndrome was diagnosed when the kidneys could not be seen and there was no amniotic fluid. In truth, the patients had ruptured membranes. Misinterpreted studies (Table 4) form another important subgroup; retrospective interpretation of the images allows a correct diagnosis to be made. Three forms of misreporting common in the past rarely if ever occur today. The most common example of this group of cases relates to obstetric sonography performed in the third trimester. For instance, an obstetric ultrasound study was interpreted as showing measurement data indicative of a 36- to 39-week pregnancy with no caveat about the inaccuracy of dating in the third trimester. At delivery, the neonate may have had hyaline membrane disease or intracranial hemorrhage. Obstetricians blamed the imager for giving a firm date that was inaccurate. A common cause of malpractice suits in the period between 1986 and 1996 was the pseudogestational sac, related to a decidual reaction containing blood ( decidual cast ), which was misinterpreted as a normal early pregnancy rather than an ectopic pregnancy (Fig. 3). Three cases in which the bladder was misinterpreted as a pelvic mass also occurred at this time (Fig. 4). Since 1996, we have seen a steady increase in misreported fetal anomalies. Spina bifida, hydrocephalus (Fig. 5), and posterior urethral valves are the most common fetal anomalies that can be recognized in retrospect when sonograms are rereviewed. By the 1980s diagnostic ultrasound had become an essential clinical tool, and a new type of litigation developed: failure to perform ultrasound, in which the standard of practice requires that an ultrasound examination be performed for a recognized indication, but none is performed (Table 5). Accepted indications for obstetric sonography have been steadily increasing; a particular impetus was a National Institutes of Health consensus conference in 1984, which promulgated 24 accepted indications for obstetric sonography. Notable are those cases in which the fundal height suggested that a pregnancy was large or small for dates, yet no ultrasound examination was done. A variety of complications occur with large-for-dates pregnancies, for example, twins and macrosomia. Oligohydramnios and intrauterine growth restriction (IUGR) were found when small-fordates pregnancies were not investigated further by sonography. An increased α-fetoprotein level, a family history of a fetal anomaly, and maternal diabetes mellitus are some of the indications for a level II ultrasound study for fetal anomalies. Many times these were not pursued with subsequent ultrasound examinations. There were also several cases in which the patient had had a previous ectopic pregnancy with a similar history in a subsequent pregnancy, yet no ultrasound examination was ordered, and a ruptured ectopic pregnancy eventually developed. Cases related to sonographers are unusual because, as a rule, the reporting physician is considered responsible for the interpretation of the study. However, litigation related to the perfor- Table 3. Invented Lesions Lesion Total Cancer of pancreas IUD in uterus Fetal death Fetal abnormality Normal pregnancy called mole IUGR Multilocular cyst vs simple cyst Gallstones and gallbladder with acute cholecystitis Fibroid Normal pregnancy called ectopic: methotrexate Retained products Total for series J Ultrasound Med 22: ,

4 Changing Patterns of Ultrasound-Related Litigation A B Figure 2. A, Sagittal gray scale view of an early pregnancy, which was thought to represent a hydatidiform mole, B, A contrast agent was injected into the early pregnancy, and the contrast-enhanced examination findings were thought to be consistent with a molar pregnancy. At termination, a normal early pregnancy was found. mance of the study rather than the interpretation may result in a suit against a sonographer. Most cases of this type were accumulated between 1986 and 1996 and are shown in Table 6. The cases of alleged sexual assault, which involved 2 physicians, including 2 female providers in addition to sonographers, occurred when the use of the vaginal probe was first popularized. Two male sonographers were accused of molesting patients in the course of abdominal sonograms. In 2 other instances, sonographers who operated mobile sonography units were sued for malpractice; the study was performed remote from the interpreting physician, and the mobile group carried substantial insurance. The use of ultrasound to guide invasive procedures has become more widespread; however, litigation in this area seems unusual except in relation to amniocentesis (Table 7). Perhaps this is because there are often multiple problems and other deficiencies that overshadow the ultrasound aspect. Abscess drainage suits, for instance, rarely focus solely on the sonography performance and interpretation. Until the 1980s, sonography was not used often as a guidance technique for amniocentesis; suits in which the complaint was failure to guide the amniocentesis with ultrasound have not been reported since Since then, suits about ultrasound and amniocentesis Figure 3. Gray scale view obtained at the time when a white background was standard showing a decidual reaction forming a pseudosac (decidual cast) in association with an ectopic pregnancy incorrectly interpreted as an early normal pregnancy, Table 4. Misinterpreted Images Finding Total Misdated fetus Fetal anomaly Decidual cast called gestational sac Wrong side of double uterus identified IUD not seen Miscalled ovarian cancer Miscellaneous Size underestimated Bladder called ovarian cyst Polyhydramnios called normal fluid Total for series J Ultrasound Med 22: , 2003

5 Sanders Figure 4. Four early gray scale views of a pelvic mass, At surgery, the pelvic mass was found to be a normal bladder. usually relate to whether guidance was continuous throughout the procedure or used only to select the needle site and whether the guidance was performed appropriately. Ultrasound fraud, as opposed to malpractice, relates to inappropriate charging practices in which additional codes are included in the charges generated for studies that were never performed. For example, a patient with right upper quadrant pain was charged separately for pancreas, liver, and gallbladder sonography. In 2 instances, indigent patients were persuaded to have unnecessary sonography in return for cash or drugs, and then the company performing the sonography generated fraudulent Medicaid and Medicare charges. An infertility expert injected human chorionic gonadotropin, making the patient feel pregnant. Weekly sonograms were obtained and billed. They allegedly showed a developing embryo. After 12 weeks, the human chorionic gonadotropin injections were stopped, and the pregnancy was said to be resorbed over the ensuing few weeks. Figure 5. Missed severe hydrocephalus, Note the dangling choroid plexus (arrow) and the lateral border of the dilated ventricle (arrowhead). J Ultrasound Med 22: ,

6 Changing Patterns of Ultrasound-Related Litigation Table 5. Failure to Perform Sonography Situation Total Before abortion Small for dates Fetal anomaly risk Aid to procedure Miscellaneous Large for dates Follow-up placenta previa Breach vs cephalic presentation Previous ectopic pregnancy Emergency sonography not available Total for series Table 6. Cases Involving Sonographers Case Neonate delivered on floor 1 Giving diagnosis to patient 1 Fracture when escorting patient 2 Patient molestation 2 Alleged sexual assault 14 Breech of confidence 2 Mobile provider 2 Total 24 Table 7. Cases Related to Invasive Procedures Procedure Total No ultrasound used for amniocentesis guidance Sonographic guidance poorly performed Ultrasound not used before abscess drainage Liver cyst aspiration resulted in pleural blood Exchange transfusion problems Total for series Table 8. Miscellaneous Cases Case Gallbladder study mixed with another Transducer pressure induced abortion 14 sonograms for IUGR Eye ultrasound burst parasitic bleb Attorney claimed he could interpret sonogram Loss of sexual desire Breech of security: twins Omitting no before IUD in report Physician failed to read report of liver stones Condyloma alleged to be due to a burst vaginal condom Wrong sex diagnosed n Tardy reporting of sonograms has occurred on a number of occasions. Reports on emergencies such as ruptured ectopic pregnancies and bleeding placenta previa have been sent by mail. Before the reports arrived, catastrophes developed. In 1 instance, a report on a fetus with IUGR took 2 weeks to arrive at the referring physician s office, by which time the fetus was dead. Communication problems of this type have not been reported in the last few years because of the new emphasis on speedy reporting. Some cases were hard to categorize and have been grouped under the title miscellaneous (Table 8). Suits have occurred that were related to careless wording of sonographic reports, such as missing the word no before intrauterine device (IUD) and effectively changing the report to say that an IUD was present. Studies have been confused so that the first gallbladder sonogram was reported as showing stones in the gallbladder when none were present, and the second gallbladder, which was filled with stones, was reported as normal. Some unsuccessful cases that were filed include an allegation of loss of sexual desire after a vaginal sonogram, an allegation that an infant was small because of excessive ultrasound when 14 sonograms had been performed to track IUGR, and an allegation that sonography performed for threatened abortion caused the fetal loss. Litigation related to diagnostic ultrasound has become progressively more frequent as images have become easier to interpret, expectations of the ability of diagnostic ultrasound to facilitate diagnoses of subtle fetal anomalies have become higher, and equipment has become more widespread. Obstetric ultrasound has always attracted more litigation than other aspects of diagnostic ultrasound. There has been a change in the main target of litigation over time: in the 1980s, ectopic pregnancy was the most common reason for litigation; today, litigation related to a missed fetal anomaly is the most frequent indication. Invented lesions, often seen in past years, almost never occur today. With greater adherence to guidelines, failure to perform sonography for a recognized indication has become a cause of litigation. Well-recognized obstetric ultrasound guidelines, in one respect, provide protection for those who perform faultless series and yet find no abnormalities when they are present and, in another respect, cause problems for those who do not document all the images required by the guidelines when abnormalities are subsequently found J Ultrasound Med 22: , 2003

7 Sanders References 1. Sanders R, Hohler CW. Legal suits involving ultrasound. J Ultrasound Med 1983; 2:R26 R Sanders RC. Update on legal complications. J Ultrasound Med 1984; 3:R103 R Sanders R. Malpractice and ultrasound. In: Ultrasound Annual 1986 New York, NY: Raven Press; Sanders R. Legal aspects of diagnostic ultrasound. Ultrasound Q 1996; 13: Sanders RC. Legal problems related to obstetrical ultrasound. Ann NY Acad Sci 1998; 847: J Ultrasound Med 22: ,