Re: Developing Accreta
From: James S Smeltzer MD (gaperina@mindspring.com)
Tue Aug 25 12:29:36 1998
Art,
Like I said. The first article predicted accreta in seven. Accreta
sufficient to cause hysterectomy occurred in one (14.3 percent) [I would
heavily discount a finding at surgery of accreta with a 1/7 rate of
hysterectomy by someone not blind to the predicted problem, and the data of
the second USC article indicate that the birth denominator for the first
should be 17,500, a few more than Beth Israel is doing]. The second was
better in positive predictive value, with hysterectomy for histologically
proven accreta in 29% of those with previa with prior multiple cesarean
sections. In the third, my series, penetrating full thickness flame-like
lakes resulted (after the initial case, which can not be legitimately
counted) in 3 of 5 with hysterectomy for hemorrhage (60 percent). Thus the
best we can do is still the flip of a coin away from an accurate diagnosis,
in terms of who we prepare for what. Until then, any patient with a previa
with a prior cesarean section needs to be ready to have a hyst.
Jim Smeltzer
(:^)>
(gaperina@mindspring.com)
At 10:53 AM 8/25/1998 -0500, you wrote:
>Jim,
>
>i've found that the learning curve factor plays a significant role in
>predictive values of diagnostic studies. here are some references which
>may be useful regarding the noninvasive dx of accreta.
>
>Radiology 1997 Dec;205(3):773-776
>
>Placenta accreta: evaluation with color Doppler US, power Doppler US,
>and MR imaging.
>
>Levine D, Hulka CA, Ludmir J, Li W, Edelman RR
>
>Department of Radiology, Beth Israel Deaconess Medical Center, Boston,
>MA 02215, USA.
>
>PURPOSE: To determine the value of transabdominal ultrasound (US),
>transvaginal US, color Doppler US, power Doppler
>US, and magnetic resonance (MR) imaging in the diagnosis of placenta
>accreta. MATERIALS AND METHODS: Nineteen
>patients in the third trimester of pregnancy who were at risk for
>placenta accreta underwent color Doppler and power Doppler
>US; 18 patients also underwent MR imaging. Images were interpreted
>prospectively for signs of accreta by two reviewers. The
>reviewers' confidence in their diagnosis was graded on a five-point
>scale. RESULTS: Outcomes at delivery were as follows:
>normal placenta (n = 11), hysterectomy owing to uncontrollable bleeding
>(n = 1), and placenta accreta (n = 7). Five cases of
>lower-uterine-segment placenta accreta were diagnosed with a high level
>of confidence with vaginal and power Doppler US. In
>one patient with a posterior placenta who had previously undergone
>myomectomy, MR imaging enabled the diagnosis of
>placenta accreta, which was not well depicted at US. CONCLUSION: In
>patients with a history of uterine scars, vaginal US
>with power Doppler US performed well in the evaluation of
>lower-uterine-segment placenta accreta. MR imaging depicts
>posterior placenta accreta.
>
>PMID: 9393534, UI: 98055252
>
>Am J Obstet Gynecol 1997 Jul;177(1):210-214
>
>Clinical risk factors for placenta previa-placenta accreta.
>
>Miller DA, Chollet JA, Goodwin TM
>
>Department of Obstetrics and Gynecology, Los Angeles County/University
>of Southern California Women's and Children's
>Hospital, Los Angeles 90033, USA.
>
>OBJECTIVE: Our purpose was to define the clinical risk factors
>associated with placenta previa-placenta accreta. STUDY
>DESIGN: Hospital records were reviewed of all cases of placenta accreta
>confirmed histologically between January 1985 and
>December 1994. Additionally, we reviewed the records of all women with
>placenta previa and all those undergoing cesarean
>hysterectomy during the same period. Multiple logistic regression
>analysis was used to identify independent clinical risk factors
>for placenta accreta. RESULTS: Among 155,670 deliveries, 62 (1/2510)
>were complicated by histologically confirmed
>placenta accreta. Placenta accreta occurred in 55 of 590 (9.3%) women
>with placenta previa and in 7 of 155,080 (1/22,154)
>without placenta previa (relative risk 2065, 95% confidence interval 944
>to 4516, p < 0.0001). Among women with placenta
>previa, advanced maternal age (> or = 35 years) and previous cesarean
>delivery were independent risk factors for placenta
>accreta. Placenta accreta was present in 36 of 124 (29%) cases in which
>the placenta was implanted over the uterine scar and
>in 4 of 62 (6.5%) cases in which it was not (relative risk 4.5, 95%
>confidence interval 1.68 to 12.07). Among women with
>placenta previa, the risk of placenta accreta ranged from 2% in women <
>35 years old with no previous cesarean deliveries to
>almost 39% in women with two or more previous cesarean deliveries and an
>anterior or central placenta previa.
>CONCLUSION: Placenta accreta occurs in approximately 1 of 2500
>deliveries. Among women with placenta previa, the
>incidence is nearly 10%. In this high-risk group advanced maternal age
>and previous cesarean section are independent risk
>factors.
>
>PMID: 9240608, UI: 97382604
>
>patient's tend to do better once folks consider the possibility.
>
>Art
>
>At Tue, 25 Aug 1998, James S Smeltzer MD wrote:
>>
>>Art,
>>
>>The last one the MRI also suggested accreta & at section, with much
>>elaborate preparation, a thin LUS had the placenta removed easily. The
>>cystoscopy idea is a good one & over the last fifteen years I have had two
>>with negative cystos, true negatives, so this and the flame-like lakes from
>>base to surface of placenta with generous flow are the best findings in my
>>hands.
>>
>>The MRI may be better able to sort out the layers, but I still do not
>>regard placenta accreta as diagnosable or excludable with a high level of
>>confidence (I have always thought it should be, but it aint).
>>
>>Jim Smeltzer MD gaperina@mindspring.com (:^]>
>>
>>At 07:38 AM 8/24/1998 -0500, you wrote:
>>>Jim,
>>>
>>>look at it this way - the U/S is a screen. if you feel that the images
>>>suggest a high risk for percreta or even increta for that matter, why
>>>not get a targeted MRI? additionally, if bladder involvement is
>>>suspected, then a cysto would shed more light i suspect. fortunately,
>>>these cases are usually few and far between but it does pay to have some
>>>additional diagnostic modalities for the tough cases. btw in our case
>>>posted awhile back, the patient's OB punted to the hospital which quite
>>>predictably took over all aspects of the case. sad to say, i have no
>>>more input and can't even obtain follow-up images. i will post the
>>>outcome, however.
>>>
>>>Art
>>>
>>>At Mon, 24 Aug 1998, James S Smeltzer MD wrote:
>>>>
>>>>At 02:44 PM 8/22/1998 -0500, you wrote:
>>>>> Did not come thru but q was detectability of percreta.
>>>>
>>>>Hi Martin,
>>>>
>>>>In my 15 years of prenatal diagnosis I have been singularly unimpressed
>>>>with my and my peers' ability to perform this simple task.
>>>>
>>>>A patient scanned at a leading sonography center came into our ER DOA
>>>>because of a percreta which was not detected or detectable by a 16 week
>>>>scan done there. I have thought I had percreta on multiple occasions to
>>>>find that I did not.
>>>>
>>>>Others have been through the same thing.
>>>>
>>>>I had an increta which was extensive that was manifested by a second stage
>>>>arrest in a 20 week miscarriage, and by numerous flame-like lakes in the
>>>>placenta (Base to surface & ramified). I did not recognize that as a
>>>>manifestation at the time. This patient died of this cause after
delivery.
>>>> I have subsequently seen this four times & three had accreta, two lost
>>>>uterus, two preterm & one normal outcome.
>>>>
>>>>This is humbling, as I approach every problem of pregnancy as diagnosable
>>>>by US until proven otherwise. Why do you ask? Jim Smeltzer MD
>>>>(perinatal@perinatal.net)
>>>
>>>--
>>>art fougner, md
>>>SonoScan/Genetic Sciences
>>>forest hills, ny
>>>evsono@pipeline.com
>>>
>
>--
>art fougner, md
>SonoScan/Genetic Sciences
>forest hills, ny
>evsono@pipeline.com
>
