Since the introduction of technetium-99m (99mTc) sestamibi (hexakis-2-methoxyisobutyl isonitrile)... more Since the introduction of technetium-99m (99mTc) sestamibi (hexakis-2-methoxyisobutyl isonitrile) as a parathyroid imaging agent in 1989, many investigators using several different imaging protocols have reported uniformly excellent results for localization of parathyroid adenomas. Exact localization of hyperplastic parathyroid glands has not met with as much success. However, the results of multiple comparative studies suggest that the diagnostic utility of sestamibi protocols equals or exceeds other noninvasive, nonscintigraphic imaging strategies, including high-resolution ultrasound, computed tomography, and magnetic resonance imaging. Two different, but not necessarily mutually exclusive imaging strategies have been used: subtraction imaging using iodine-123 (123I) or 99mTc sodium pertechnetate as the thyroid agent, and sestamibi dual-phase imaging, which takes advantage of differential washout of sestamibi from thyroid and parathyroid tissue. Sestamibi subtraction imaging has been shown to have greater sensitivity for abnormal parathyroid glands compared with thallium-201 subtraction imaging using pooled data, 87% versus 71%, respectively. Dual-phase sestamibi imaging protocols are much more variable in their conduct and have a much greater variability in sensitivity, 43% to 91%, but with a pooled sensitivity of 73%. Data suggest that dual phase techniques are at least as sensitive, and in optimized protocols, superior to, thallium-201 subtraction techniques. This superiority is attributed to the favorable washout kinetics of sestamibi and the superior imaging characteristics of the 99mTc label. Specificity and positive predictive value for both sestamibi techniques are very high, typically greater than 90% and at least equal to thallium-subtraction protocols, although specificity may be slightly lower for sestamibi subtraction techniques. Therefore, sestamibi protocols are the scintigraphic procedure of choice for parathyroid imaging. Dual-phase sestamibi protocols are more robust and lend themselves to single photon emission computer tomography (SPECT) imaging, and may be followed sequentially by subtraction techniques if results are inconclusive. Despite the excellent results of sestamibi parathyroid imaging, it is unclear whether this accuracy can compete with the even better success of an experienced surgeon in initial surgeries for hyperparathyroidism, and routine preoperative imaging before initial surgery is still controversial. However, sestamibi parathyroid imaging is an excellent addition to a correlative imaging approach in reoperations for persistent and recurrent hyperparathyroidism.
This study was conducted to investigate and illustrate the use of Indium In-111 pentetreotide sci... more This study was conducted to investigate and illustrate the use of Indium In-111 pentetreotide scintigraphy as it applies to carotid body tumors (CBT). Localization has relied primarily on ultrasonography, computed tomography, and magnetic resonance imaging with angiographic confirmation. These methods only assess the cervical bifurcation without providing an evaluation of metastasis in patients without symptoms or recurrence in patients after surgery. Indium In-111 pentetreotide scintigraphy was used in five patients with a diagnosis of CBT. Four patients were evaluated after surgical excision for evidence of tumor recurrence. One patient was evaluated before excision for diagnostic confirmation. No evidence of tumor recurrence was demonstrated in the four patients who had undergone previous CBT excision. One of these patients had increased activity in the pituitary, later confirmed as an enlarged pituitary without evidence of an adenoma with computed tomography. The diagnosis of CBT was confirmed in the patient evaluated before surgery. This patient also had increased activity in the occipital region, confirmed as the site of previous ischemia on computed tomography. Indium In-111 pentetreotide scintigraphy is a new innovative method for viewing neuroendocrine tumors. Its potential lies not only in tumor localization but also in identification of recurrent tumor at the operative site and metastatic disease.
Radiographic correlation is essential for many of the examinations performed in nuclear medicine.... more Radiographic correlation is essential for many of the examinations performed in nuclear medicine. The purpose of this study was to evaluate the impact of a picture archiving and communications system (PACS) on the function and efficiency of a nuclear medicine department at a tertiary care institution. We evaluated 250 consecutive noncardiac nuclear medicine imaging examinations and asked the interpreting physician the following questions: (1) Was PACS used in the interpretation of the study? (2) Did the use of PACS expedite examination completion or aid in study interpretation? And (3) Did the use of PACS permit a definitive diagnosis to be made? PACS was accessed for correlative radiographic images in 155 of the 250 (62%) nuclear medicine examinations. Images available on PACS for review aided in study interpretation in 74% (115 of 155) of cases. The use of PACS was thought to expedite examination completion in 55% (86 of 155) of cases. The system was accessed but not operational in only 1% of cases (2 of 155). PACS provides reliable, rapid access to multimodality correlative radiographic images that aid in the interpretation of nuclear medicine examinations. Such systems also increase the efficiency of a nuclear medicine service by allowing timely and conclusive interpretations to be made.
Since the introduction of technetium-99m (99mTc) sestamibi (hexakis-2-methoxyisobutyl isonitrile)... more Since the introduction of technetium-99m (99mTc) sestamibi (hexakis-2-methoxyisobutyl isonitrile) as a parathyroid imaging agent in 1989, many investigators using several different imaging protocols have reported uniformly excellent results for localization of parathyroid adenomas. Exact localization of hyperplastic parathyroid glands has not met with as much success. However, the results of multiple comparative studies suggest that the diagnostic utility of sestamibi protocols equals or exceeds other noninvasive, nonscintigraphic imaging strategies, including high-resolution ultrasound, computed tomography, and magnetic resonance imaging. Two different, but not necessarily mutually exclusive imaging strategies have been used: subtraction imaging using iodine-123 (123I) or 99mTc sodium pertechnetate as the thyroid agent, and sestamibi dual-phase imaging, which takes advantage of differential washout of sestamibi from thyroid and parathyroid tissue. Sestamibi subtraction imaging has been shown to have greater sensitivity for abnormal parathyroid glands compared with thallium-201 subtraction imaging using pooled data, 87% versus 71%, respectively. Dual-phase sestamibi imaging protocols are much more variable in their conduct and have a much greater variability in sensitivity, 43% to 91%, but with a pooled sensitivity of 73%. Data suggest that dual phase techniques are at least as sensitive, and in optimized protocols, superior to, thallium-201 subtraction techniques. This superiority is attributed to the favorable washout kinetics of sestamibi and the superior imaging characteristics of the 99mTc label. Specificity and positive predictive value for both sestamibi techniques are very high, typically greater than 90% and at least equal to thallium-subtraction protocols, although specificity may be slightly lower for sestamibi subtraction techniques. Therefore, sestamibi protocols are the scintigraphic procedure of choice for parathyroid imaging. Dual-phase sestamibi protocols are more robust and lend themselves to single photon emission computer tomography (SPECT) imaging, and may be followed sequentially by subtraction techniques if results are inconclusive. Despite the excellent results of sestamibi parathyroid imaging, it is unclear whether this accuracy can compete with the even better success of an experienced surgeon in initial surgeries for hyperparathyroidism, and routine preoperative imaging before initial surgery is still controversial. However, sestamibi parathyroid imaging is an excellent addition to a correlative imaging approach in reoperations for persistent and recurrent hyperparathyroidism.
This study was conducted to investigate and illustrate the use of Indium In-111 pentetreotide sci... more This study was conducted to investigate and illustrate the use of Indium In-111 pentetreotide scintigraphy as it applies to carotid body tumors (CBT). Localization has relied primarily on ultrasonography, computed tomography, and magnetic resonance imaging with angiographic confirmation. These methods only assess the cervical bifurcation without providing an evaluation of metastasis in patients without symptoms or recurrence in patients after surgery. Indium In-111 pentetreotide scintigraphy was used in five patients with a diagnosis of CBT. Four patients were evaluated after surgical excision for evidence of tumor recurrence. One patient was evaluated before excision for diagnostic confirmation. No evidence of tumor recurrence was demonstrated in the four patients who had undergone previous CBT excision. One of these patients had increased activity in the pituitary, later confirmed as an enlarged pituitary without evidence of an adenoma with computed tomography. The diagnosis of CBT was confirmed in the patient evaluated before surgery. This patient also had increased activity in the occipital region, confirmed as the site of previous ischemia on computed tomography. Indium In-111 pentetreotide scintigraphy is a new innovative method for viewing neuroendocrine tumors. Its potential lies not only in tumor localization but also in identification of recurrent tumor at the operative site and metastatic disease.
Radiographic correlation is essential for many of the examinations performed in nuclear medicine.... more Radiographic correlation is essential for many of the examinations performed in nuclear medicine. The purpose of this study was to evaluate the impact of a picture archiving and communications system (PACS) on the function and efficiency of a nuclear medicine department at a tertiary care institution. We evaluated 250 consecutive noncardiac nuclear medicine imaging examinations and asked the interpreting physician the following questions: (1) Was PACS used in the interpretation of the study? (2) Did the use of PACS expedite examination completion or aid in study interpretation? And (3) Did the use of PACS permit a definitive diagnosis to be made? PACS was accessed for correlative radiographic images in 155 of the 250 (62%) nuclear medicine examinations. Images available on PACS for review aided in study interpretation in 74% (115 of 155) of cases. The use of PACS was thought to expedite examination completion in 55% (86 of 155) of cases. The system was accessed but not operational in only 1% of cases (2 of 155). PACS provides reliable, rapid access to multimodality correlative radiographic images that aid in the interpretation of nuclear medicine examinations. Such systems also increase the efficiency of a nuclear medicine service by allowing timely and conclusive interpretations to be made.
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Papers by Mike McBiles