The sestamibi scan done on me at norman parathyroid center on april 4, 2016 just hours before my surgery was inconclusive, but those highly skilled surgeons found the offending adenoma, the size of a raisin, producing 543 pth 3080 normal. Sometimes the sestamibi scan or the 4d ct scan can show this prior to surgery, and guide the approach, which is still often via the neck. This finding can increase diagnostic confidence that a suspicious lesion is a parathyroid adenoma instead of a lymph node or thyroid nodule. The next two phases are contrastenhanced phases from the angle of the mandible to the carina and are performed after iv administration of 75 ml. The characteristic description of a parathyroid adenoma on 4d ct scan is a lesion with lower attenuation than that of the thyroid gland in the noncontrastenhanced phase, peak enhancement greater than that of the thyroid gland in the arterial phase, and washout of contrast material in the delayed phase 24. Mount sinai endocrine surgery parathyroid center this consultation describes the role of parathyroid ct scanning in parathyroid gland localization. Comparison of sestamibi spectct and parathyroid 4d ct. Parathyroid scan definition of parathyroid scan by medical. Preoperative localization of parathyroid tumors endocrineweb. Ct protocols for common primary care diagnoses lacey j.
Lifetime attributable risk of cancer from radiation exposure. The 4d ct parathyroid examinations at our institution are performed by using a 64detector row ct scanner 750 hd. Parathyroid scans for abnormal parathyroid glands dr. Endocrine tumor and bone disease program saint johns. Ultrasound performed by a tech at your local xray place will find less than 25% of parathyroid tumors primarily because the physician that orders the scan. A parathyroid scan is a noninvasive procedure that uses two radiopharmaceuticals drugs with a radioactive marker to obtain an image of highly active areas of the parathyroid glands. Parathyroid fourdimensional 4d computed tomography ct is an imaging technique for preoperative localization of parathyroid adenomas that involves. The sestamibi scan is now the preferred method for identifying a diseased parathyroid gland prior to an operation. A ct scan is a special computer that makes detailed pictures of your internal organs and bones through the use of xrays. Diagnostic tests, procedures, equipment parathyroid scan. There are technique differences which make these scans at some hospitals much better than they are at other hospitals.
There are four parathyroid glands, which are usually located behind the thyroid gland and, in rare cases, within the thyroid gland or in the chest. Pdf comparison of 4d ct, ultrasonography, and 99mtc. The purpose of our study is to assess the accuracy of 4dct for localizing pathologically proved parathyroid adenomas. If the test is to be performed immediately, the patient lies down on an imaging table with his head and neck extended and. To image the parathyroid glands before a repeat operation for recurrent or persistent disease, technetium99m sestamibi 99m tc mibi scanning and magnetic resonance imaging mri are the preferred imaging modalities because of their high sensitivities in depicting ectopic or mediastinal glands. Parathyroid fourdimensional 4d computed tomography. Spect scanning for parathyroid glands endocrineweb. Fourdimensional 4d computed tomography ct for parathyroid imaging is a technique that was first reported in the surgical literature in 2006. The purpose of our study is to assess the accuracy of 4dct for localizing pathologically proven parathyroid adenomas and hyperplasia found at surgery.
Using 4dct imaging to optimize surgery for hyperparathyroidism. A parathyroid tumor found on an ultrasound is a parathyroid tumor that any experienced parathyroid surgeon would find during a routine parathyroid operation, with a few rare exceptions. Parathyroid 4dct is a more specialized ct scan with greater ability to locate diseased glands. Ct scanning is fast, painless, noninvasive and accurate. Number 1 january 2014 f ourdimensional 4d computed to mography ct for parathyroid imaging is a technique that was first reported in the surgical literature in 2006 1. The patient is given intravenous contrast iodinebased. Parathyroid fourdimensional computed tomography 4dct is a technique that uses sophisticated xray technology to locate the parathyroid glands in the neck. This page is for physicians, inside and outside this institution, and ct technologists.
Diagnostic accuracy of 4dct for parathyroid adenomas and. Initial noncontrast enhanced axial image of the upper neck at the level of the upper pole of the right thyroid gland t shows the normal neck anatomy including. If 4 out of 5 points are assigned to a lesion on 4d ct, there is a high level of accuracy in localizing eutopic parathyroid adenomas. If 4 out of 5 points are assigned to a lesion on 4dct, there is a high level of accuracy in localizing eutopic parathyroid adenomas. The resolution of 4d ct imaging is higher than that of any other type of parathyroid scan. In recent years, multiphase parathyroid 4d ct has evolved from an adjunct imaging technique to a firstline choice for planning parathyroidectomy at some institutions. Comparison of sestamibi spectct and parathyroid 4d ct with a. The protocol consists of three imaging phases fig 1. For localization of parathyroid adenoma updated jan 23, 2017 positionlandmark head first or feet firstsupine sternal notch topogram direction craniocaudal respiratory phase inspiration scan type helical kv ma rotation time sec pitch speed mmrotation. Rih parathyroid 4d neck ge lightspeed 16 optima ct580 protocol indication. Parathyroid 4dct is a more specialized ct scan with greater ability to locate diseased. The parathyroids are four small hormone glands lying close to or embedded in the back surface of the thyroid gland, in the front of the neck. Lp riccelli works closely with ohsu ct techs in the art of creating optimal images from current technology.
My calcium was elevated for the better part of 16 years, my pth was never higher than 61, but more in the 20s, 30s and 40s. For any given ct examination, the protocol will vary according the individual requirement of the imaging site. Dynamic contrastenhanced ct and mr imaging for preoperative. Parathyroid glands control the amount of calcium in the blood and within the bones. Almost 100 percent correct when it shows a single gland. Preparing for parathyroid surgery, endocrine surgery uw. Fourdimensional parathyroid ct 4dct is a specialized imaging study that was first introduced in 2006 for the purpose of identifying abnormal parathyroid glands in the planning of parathyroid surgery. Early experience with a novel imaging technique in. Parathyroid localization using 4dcomputed tomography. Dynamic 4d mri for characterization of parathyroid adenomas. One advantage of 4d ct over slow ct, mentioned above, is that the image in each respiratory bin is quite sharp. Computerized tomography ct or cat scan when done correctly, computerized tomography also referred to as a ct or cat scan can be a very helpful tool to find the enlarged parathyroids.
We offer same day evaluation and treatment planning, including stateoftheart 3d parathyroid imaging for parathyroid disease. At stony brook medicine, we have added to our set of imaging tools the latest technology in parathyroid imaging, called fourdimensional computed tomography ct, or 4dct, to improve the treatment we provide for hyperparathyroidism the resolution of 4dct imaging is higher than that of any other type of parathyroid scan. Parathyroid scan continued page 2 of 2 acquire spect images of the neckupper chest with arms down mmediatelyi after the initial planar images. Parathyroid adenomas and hyperplasia on fourdimensional. Parathyroid fourdimensional computed tomography 4dct has mainly been used as an adjunct to other imaging modalities in the remedial setting. Parathyroid 4dct scan parathyroid fourdimensional computed tomography 4dct is a technique that uses sophisticated xray technology to locate the parathyroid glands in the neck.
Using coregistered images, we placed rois over the parathyroid adenoma, thyroid gland, and a cervical lymph node jugulodigastric to obtain peak enhancement, timetopeak. And although we have modified our 4d ct scan protocol to minimize the dose of radiation it still is a consideration, especially in younger patients. The parathyroid scan uses sestamibi or mibi for short, which is a very safe liquid. The patient is given intravenous contrast, which is an iodinebased dye that enhances the quality of imaging. On 4dct parathyroid adenomas typically demonstrate intense enhancement on arterial phase, washout of contrast on delayed phase and low attenuation on noncontrast imaging 12. Comparison between mr imaging and 99mtc mibi scintigraphy in the evaluation of recurrent of persistent hyperparathyroidism. Reducing the scan length of two phases in the dynamic ct protocol could reduce the median effective dose to 6. Spect scans are performed on patients with parathyriod disease and can be used for miniparathyroid surgery. Kim are the only readers for this exam indications. Parathyroid glands are small endocrine glands in the neck that produce parathyroid hormone. Parathyroid operations use sestamibi and spect scans alsodiscussed by parathyroid surgeons who treat parathyroid disease. In these patients, the fine resolution provided by 4d ct helps us to minimize our surgery, which not only increases the chance for a cure but also reduces the risk of. Fourdimensional parathyroid ct 4d ct is a specialized imaging study that was first introduced in 2006 for the purpose of identifying abnormal parathyroid glands in the planning of parathyroid surgery. The protocol consists of three imaging phases performed on a 64mdct scanner 750 hd, ge healthcare.
This process allows a complete examination of the contrast enhancement and washout characteristics of parathyroid adenomas on 4d ct, without reducing the number of scan phases. However, once in a while this is not the case, and parathyroid tissue may be located elsewhere, for example in the chest. Ct in the past, ct was more commonly used in the setting of a failed parathyroidectomy for the detection of suspected ectopic glands often mediastinal 6. Preoperative highspatial and temporal resolution dynamic 4d contrastenhanced mr imaging in 30 patients with surgically proved parathyroid adenomas was evaluated retrospectively. Parathyroid adenoma detection with 4d ct by dr jenny hoang in recent years 4d ct has emerged as a useful imaging technique in the workup of patients with primary hyperparathyroidism to allow sensitive detection and localization of parathyroid adenomas and parathyroid hyperplasia. It outlines ct protocols for diagnostic imaging currently applied to ou ct scanners. Parathyroid scan definition a parathyroid scan is sometimes called a parathyroid localization scan or parathyroid scintigraphy. The available literature has not yet reached a consensus on the optimal 4dct scanning protocol for parathyroid imaging. Preoperative 4d ct localization of nonlocalizing parathyroid. Twophase lowdose computed tomography is as effective as 4d. A novel nomenclature to classify parathyroid adenomas. Should only be done on patients with a high calcium and a high parathyroid hormone.
Three hundred fifty seven patients with primary hyperparathyroidism who underwent parathyroid imaging protocol and. Parathyroid adenoma detection with 4dct radiology blog. Factors that infl uence a specifi c sites protocol parameters include the type of equipment available e. Parathyroid fourdimensional 4d computed tomography ct is an imaging technique for preoperative localization of parathyroid adenomas that involves multidetector ct image acquisition during two. Parathyroid adenoma detection with 4dct by dr jenny hoang in recent years 4dct has emerged as a useful imaging technique in the workup of patients with primary hyperparathyroidism to allow sensitive detection and localization of parathyroid adenomas and parathyroid hyperplasia. A parathyroid scan is for localization of hyperparathyroidism or overactive parathyroid glands. Parathyroid scan definition of parathyroid scan by. Sestamibi scans, spect scans, 4d ct scan for parathyroid problems and parathyroid disease. Tc99m mibi imaging has a sensitivity of 7095% in depicting.
Jun 11, 2014 another addition to parathyroid imaging has been the 4d ct also referred to as multidimensional ct. Pdf parathyroid fourdimensional 4d computed tomography ct is an imaging technique for. The resolution of 4dct imaging is higher than that of any other type of parathyroid scan. Fourdimensional parathyroid ct 4dct is a specialized imaging study that was first introduced in 2006 for the purpose of identifying. Mowschenson, md 4d ct imaging this is the latest test available and it can be extremely helpful when the sestamibi scan and ultrasound do not show the enlarged parathyroid s. This scan uses radioactive pharmaceuticals that are readily taken up by cells in the parathyroid glands to obtain an image of the glands and any abnormally active areas within them. Mcintosh do, mph university of massachusetts medical center. Dec 24, 2010 preoperative localization of parathyroid tumors of primary hyperparathyroidism phpt is required for minimally invasive parathyroidectomy mip. Jan 30, 2017 radiologic localization of parathyroid lesions is essential for the surgical treatment of primary hyperparathyroidism.
For spect only cameras, images should be acquired in a collar. We hypothesize that a simpler twophase ct protocol would have a similar. An approach to protocol evaluation jean yoder, casimir eubig, t. A number of experts believe that spect scanning for parathyroid disease enables them to increase the accuracy of routine sestamibi scanning by about 2 to 3 percent.
Aug 15, 20 our modified 4d ct protocol uses virtual noncontrast vnc images obtained from dualenergy ctreconstructed venousenhanced images to replace true precontrast scans. Dualenergy 4phase ct scan in primary hyperparathyroidism. Using the manufacturers default protocol, patient dose is relatively. However, it also exposes the patient to the highest dose of radiation. The first phase is an unenhanced ct to cover the thyroid gland. We have derived a practical 5 point scoring system for parathyroid ct scan imaging. Parathyroid 4d ct is especially useful when other imaging studies fail to detect or locate abnormal glands, and when patients have a history of prior failed parathyroid surgery. The parathyroid spect scan finds the diseased parathyroid gland. Radiologic localization of parathyroid lesions is essential for the surgical treatment of primary hyperparathyroidism. In the absence of mri contraindication, 4d parathyroid mri was the default diagnostic test for preoperative parathyroid imaging in patients with suspicion of parathyroid adenoma, if crosssectional imaging was needed. There is, however, typically more noise in 4d ct images versus a standard helical scan because vendor protocols typically reduce the ma in 4d ct scans in order to limit the dose. The imaging protocol consisted of consecutively acquired dual phase sestamibi spect ct and 4d ct, with 4d ct acquired immediately after the delayed phase sestamibi spect ct acquisition and the patient in the same position and spect ct scanner. When used to localize parathyroid adenomas and hyperplasia, this technique may allow for more robust diagnostic accuracy than traditional sonography and nuclear scintigraphy techniques.
Preoperative localization of parathyroid tumors of primary hyperparathyroidism phpt is required for minimally invasive parathyroidectomy mip. Lifetime attributable risk of cancer from radiation. Utility of 4dct imaging in the diagnosis of a parathyroid. The following documents are radiology protocols for all medical imaging sites at which tra medical imaging is responsible for the administration, quality and interpretation of medical imaging examinations. Conditions saint johns treats patients with even the most complex endocrine and adrenal cancers and conditions, including. The first phase is a nonenhanced ct study to cover the thyroid gland. Current and accurate patient information guide about parathyroid fourdimensional computed tomography 4dct scans. These protocols were discussed and agreed upon by members of each subspecialty section within tra medical imaging.
The information provided should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. Three hundred fifty seven patients with primary hyperparathyroidism who underwent parathyroid imaging protocol and parathyroidectomy were included. Almost all parathyroid glands are found close to the thyroid gland in the neck. The purpose of this study was to compare the radiation dose delivered by threephase dynamic ct with that delivered by 99m tcsestamibi spect ct performed in accordance with our current protocols and to assess the possible reduction in effective dose achieved by decreasing the scan length i. I was delighted by the fast adoption of our 4d mri across our institution at the time. Spect single proton emission computerized tomography scanning is a new technique whereby images can be obtained of diseased glands which have absorbed a radioactive marker.
Parathyroid spect scans discussed by parathyroid experts. The nuclear medicine scan can be fused with the ct scan as a spect scan to increase diagnostic accuracy and aid in anatomical localization. The key difference between ct and 4d ct is that the latter is used to obtain. In recent years, multiphase parathyroid 4dct has evolved from an adjunct imaging technique to a firstline choice for planning parathyroidectomy at some institutions. Localization by 4d ct correlated with tissue parathyroid hormone level p. Objectiveto evaluate 4dimensional 4d computed tomography ct for the localization of parathyroid adenomas previously.
In fact, it can identify abnormal parathyroid glands as small as 2 inch x 14 inch, that is, around the size of a tiny lentil. Patterns of enhancement relative to the thyroid gland justify a threephase protocol. Its difference compared to a 3d ct is the fourth dimension with contrast enhancement. A parathyroid mibi scan is used in nuclear medicine to look at possible problems involving the parathyroid gland s. For spectct, the ct acquisition to the region goes from the nose through the base bottom of the heart.
A prominent feeding artery at the margin of a parathyroid adenoma polar vessel, first described on ultrasound, may be seen in up to two thirds of parathyroid adenomas on highquality 4dct studies. The key difference between ct and 4d ct is that the latter is used to obtain additional information about the parathyroid lesion from imaging in two or more contrast materialenhanced phases. The 4d parathyroid ct scan is able to identify an enlarged parathyroid better then the other scans mentioned on this page. A licensed physician should be consulted for diagnosis and treatment of any and all medical conditions. Another addition to parathyroid imaging has been the 4dct also referred to as multidimensional ct. Parathyroid adenomas typically enhance avidly on earlyphase imaging, and the hyperenhancement persists despite a long delay after contrast administration.1153 1099 1571 138 1587 1095 1305 357 1454 116 1182 1109 1358 464 116 289 332 249 486 1509 1112 791 883 1600 454 600 678 1400 990 870 320 1318 13 966 210 636 871 982 682 1363 1401 29 458 1288 458