Decreased mebrofenin uptake in patients with non-colorectal liver tumors requiring liver volume augmentation-a single-center analysis.

BACKGROUND: Posthepatectomy liver failure (PHLF) remains a life-threatening complication after hepatectomy. To reduce PHLF, a preoperative assessment of liver function is indispensable. For this purpose, 99mTc-mebrofenin hepatobiliary scintigraphy with SPECT (MSPECT) can be used. The aim of the current study was to evaluate the predictive value of MSPECT for PHLF in patients with non-colorectal liver tumors (NCRLT) compared to patients with colorectal liver metastasis (CRLM) undergoing extended liver resection. METHODS: We included all patients undergoing extended liver resections via two-stage procedures between January 2019 and December 2021 at the University Medical Center Hamburg-Eppendorf, Germany. All patients received a preoperative MSPECT. RESULTS: Twenty patients were included. In every fourth patient, PHLF was observed. Four patients had PHLF grade C. There were no differences between patients with CRLM and NCRLT regarding PHLF rate and future liver remnant (FLR) volume. Patients with CRLM had higher mebrofenin uptake in the FLR compared to those with NCRLT (2.49%/min/m2 vs. 1.51%/min/m2; p = 0.004). CONCLUSION: Mebrofenin uptake in patients with NCRLT was lower compared to those patients with CRLM. However, there was no difference in the PHLF rate and FLR volume. Cut-off values for the mebrofenin uptake might need adjustments for different surgical indications, surgical procedures, and underlying diseases.

Performance evaluation of a novel multi-pinhole collimator for dopamine transporter SPECT.

There is a tradeoff between spatial resolution and count sensitivity in SPECT with conventional collimators. Multi-pinhole (MPH) collimator technology has potential for concurrent improvement of resolution and sensitivity in clinical SPECT of 'small' organs. This study evaluated a novel MPH collimator specifically designed for dopamine transporter (DAT) SPECT with a triple-head SPECT camera. Count sensitivity was measured with a 99mTc point source placed on the lattice points of a 1 cm grid covering the whole field-of-view (FOV). Spatial resolution was assessed with a Derenzo type hot rod phantom. An anthropomorphic striatum phantom was scanned with total activity representative of a typical patient scan and different striatum-to-background activity concentration ratios. Recovery of striatum-to-background contrast was assessed by the contrast-recovery-coefficient. Measurements were repeated with double-head SPECT with fan-beam or low-energy-high-resolution-high-sensitivity (LEHRHS) collimators. A patient referred to DAT SPECT because of suspicion of Parkinson's disease was scanned with both LEHRHS and MPH collimators after a single tracer injection. The axial MPH sensitivity profile was approximately symmetrical around its peak, although it was shifted 7 cm towards the patient to simplify positioning. Peak sensitivity of the triple-head MPH system in the center of the FOV was 620 cps MBq-1 compared to 225 cps MBq-1 for the double-head fan-beam system. Sensitivity of the MPH system decreased towards the edges of the FOV. The full width of the sensitivity profile at 200 cps MBq-1 was 21 cm transaxially and 11 cm axially. In MPH SPECT of the Derenzo phantom all rods with ≥ 5 mm diameter were clearly visible. MPH SPECT improved striatal contrast recovery by ≥ 20% compared to fan-beam SPECT. The patient scan demonstrated good image quality of MPH SPECT with almost PET-like delineation of putamen and caudate nucleus. SPECT with dedicated MPH collimators provides considerable improvement of the resolution-sensitivity tradeoff in DAT SPECT compared to SPECT with fan-beam or LEHRHS collimators.

[Positron emission tomography in germ cell tumors in men : Possibilities and limitations]. / Positronenemissionstomographie bei Keimzelltumoren des Mannes : Einsatzmöglichkeiten und Grenzen.

BACKGROUND: Conventional radiographic imaging may fail to safely distinguish clinical stage I from stage IIA germ cell cancer, to localize isolated tumor marker relapses, and to equivocally identify the viability of postchemotherapy residual masses. OBJECTIVES: To provide an overview of the diagnostic value and limitations of functional imaging by positron emission tomography with 2­deoxy-2-[fluorine-18]fluoro-D-glucose with computed tomography (18F-FDG-PET-CT) in male germ cell cancer. MATERIALS AND METHODS: A narrative review based on a literature search of PubMed/MEDLINE for original articles published from 1990-2018 and conference proceedings of ASCO (American Society of Clinical Oncology) and EAU (European Association of Urology) annual meetings 2014-2017 is presented. RESULTS: 18F-FDG-PET-CT does not improve diagnostic accuracy compared to conventional CT imaging clinical stage (CS) I disease. Particularly PET-negativity of postchemotherapy residual masses of seminomas >3 cm in size guide decision-making against further additional treatment. Even PET-positive residues must not result in relapse. For nonseminoma, the value of PET imaging is reduced by potential mature teratoma components, which are commonly PET negative. CONCLUSIONS: Current guidelines recommend 18F-FDG-PET-CT 6-8 weeks postchemotherapy for viability assessment of seminoma residues >3 cm in size. Exceptional circumstances, in which 18F-FDG-PET-CT may be helpful, include: (1) detection of active disease in CS IS, (2) viability assessment of residual masses >1 cm where complete secondary resection is impossible, (3) staging at marker relapse with unconspicuous conventional CT scan, (4) early response assessment during chemotherapy.

[Alpha emitter radium-223 dichloride: new therapy in castration-resistant prostate cancer with symptomatic bone metastases]. / Alphastrahler Radium-223-Dichlorid: Neue Therapie beim kastrationsresistentes Prostatakarzinom mit symptomatischen Knochenmetastasen.

Radium-223 dichloride (Ra-223) is an alpha emitter with low toxicity for the treatment of patients with castrations-resistant prostate cancer (CRPC) and symptomatic bone metastases showing a 30% reduction in the risk of death, as compared to placebo. Because of the favorable physical and chemical characteristics, Ra-223 can be handled easily in daily practice based on interdisciplinary co-operation between urology and nuclear medicine. Ra-223 has been approved under the product name Xofigo® by the US Food and Drug Administration (FDA) and the European Medicines Agency (EMA).

IBZM SPECT and FDG PET in the differential diagnosis of Parkinsonian syndromes: comparison with respect to inter-rater agreement.

AIM: Both IBZM SPECT and FDG PET may be used for differentiation between Parkinson's disease (PD) and atypical neurodegenerative parkinsonian syndromes (APS). However, there are only very limited data of both modalities in the same subjects. The present study compared both modalities with respect to inter-rater agreement in 30 patients with neurodegenerative parkinsonian syndromes (PS) confirmed by FP-CIT SPECT. METHODS: IBZM SPECT and FDG PET were categorized as PD or APS by visual inspection of standardized report pages and statistical parametric maps (SPMs). Categorization was performed independently by five readers. Inter-rater agreement was quantified using Cohen's kappa kappa. RESULTS: IBZM SPECT resulted in PD and APS in 11 and 19 cases, respectively (majoritarian categorization). Inter-rater agreement was kappa=0.64+/-0.10. FDG PET resulted in PD and APS in 12 and 18 cases, respectively (majoritarian categorization). Inter-rater agreement was kappa=0.68+/-0.07. Majoritarian diagnosis disagreed between IBZM SPECT and FDG PET in 13 cases (43%). Semi-quantitative analysis of IBZM SPECT using the striatum-to-reference distribution volume ratio was in good agreement with visual categorization (area under ROC curve 0.92). CONCLUSION: In neurodegenerative PS, inter-rater agreement of visual analysis is substantial in both IBZM SPECT and FDG PET. Furthermore, (I) visual analysis of IBZM SPECT is reliable if adequate standardized image display is used, (II) visual analysis of FDG SPMs allows unique categorization as either PD or APS in most subjects, and (III) IBZM SPECT and FDG PET are discordant in a significant fraction of cases.

[F(18)]-fluoroethylcholine combined in-line PET-CT scan for detection of lymph-node metastasis in high risk prostate cancer patients prior to radical prostatectomy: Preliminary results from a prospective histology-based study.

PURPOSE: To evaluate the diagnostic potential of PET/CT using ([F(18)]fluorethylcholine (FEC) for lymph node (LN) staging in high risk prostate cancer (PCa) patients prior to radical prostatectomy (RP). PATIENTS AND METHODS: Twenty patients with localised PCa and > or =20% LN risk according to a published nomogram were prospectively enrolled. FEC PET/CT was done minimum 14 d after prostate biopsy. Afterwards, open RP and extended pelvic LN dissection (ePLND) were performed. Clinical stage, Prostate Specific Antigen (PSA) and biopsy Gleason Grading were assessed and histopathological evaluation of the RP-specimens and dissected LN has been performed. The results from PET/CT were compared with LN metastasis according to their anatomical site. RESULTS: Overall, 285 LN have been removed with a mean number of 15 nodes per patient (7-26). Of the 20 patients, 9 men were LN positive (45%), which corresponds to 31 positive LN with a mean size of 7 mm (0.8-12 mm). Dissection of the obturator fossa, external iliac artery/vein and internal iliac artery/vein revealed 36%, 48% and 16% of positive LN, respectively. FEC PET/CT did not detect one single positive LN, thus was false-negative in 31 metastasis and true negative in 254 LN. CONCLUSION: Based on our results which confirmed experience from the previous studies, FEC PET/CT scan did not prove to be useful for LN staging in localised PCa prior to treatment and should thus not be applied if clinically occult metastatic disease is suspected.

Experience with 123I-iomazenil SPECT in acute cerebral infarction.

Neuronal cells are susceptible to cerebral ischaemia. As gamma-aminobutyric acid(A) (GABA(A)) receptors are specific for neurones, functional receptor imaging using I-iomazenil (IMZ), a ligand to the GABA benzodiazepine receptor, has been proposed as an imaging modality for the assessment of neuronal integrity. However, there is only limited experience with IMZ in patients with acute cerebral infarction. Therefore, the aim of this study was to evaluate IMZ single photon emission computed tomography (SPECT) in patients with acute cerebral ischaemia. IMZ SPECT was performed in 21 patients with acute cerebral infarction 7-10 days after stroke onset. Eleven patients underwent systemic thrombolysis within 6 h after symptom onset (group 1), whereas 10 patients were treated conservatively (group 2). IMZ (150-200 MBq) was injected intravenously and imaging was performed using a dedicated four-head SPECT camera at 5 min (perfusion) and 90 min (receptor distribution) post-injection, with an acquisition time of 50 min each. Images were analysed by visual inspection. Four patients showed normal IMZ distribution, and 17 patients showed abnormalities of IMZ uptake on both early and late images. In six patients with regional uptake deficits, a crossed cerebellar diaschisis was observed on early images. Cerebellar inhomogeneity of tracer uptake was absent at the time of late images in all six patients. In eight patients, areas of hypoperfusion corresponded exactly to the regions of receptor deficiency (match). In five patients, preserved neuronal integrity was present in hypoperfused areas (mismatch). In four patients, normally or even hyperperfused areas exhibited regional receptor deficiency (inverse mismatch). In conclusion, IMZ SPECT demonstrated differences between regional perfusion and receptor distribution in about one-half of patients 7-10 days after acute cerebral ischaemia. Interesting patterns between the early phase (perfusion) and the late phase (receptor distribution) were found. These patterns are indicative of the heterogeneous development of cerebral ischaemia where, even days after stroke onset, areas of hypoperfusion but preserved neuronal integrity may be present. However, the evaluation of the potential clinical and therapeutic impact of individual IMZ distribution patterns requires further investigation.

[Prevalence of iodine- and thyroglobulin-negative findings in differentiated thyroid cancer.A retrospective analysis of patients treated from 1951 to 1998 in university hospital]. / Häufigkeit lod- und hTG-negativer Befunde beim differenzierten Schilddrüsenkarzinom. Eine retrospektive Analyse der von 1961 bis 1998 in einer Universitätsklinik behandelten Patienten.

AIM: The prevalence of iodine- and thyroglobulin-negative findings was evaluated in all patients with differentiated thyroid cancer (DTC) treated from 1961 until 1998 at the Department of Nuclear Medicine, University Hospital Hamburg-Eppendorf. METHODS: A total of 490 patients with papillary thyroid cancer (PCA) and 242 patients with follicular thyroid cancer (FCA) were analyzed retrospectively. Patients were divided into four groups: 1: no recurrence, 2: recurrent disease, 3: primary metastatic/progressive disease and 4: inconclusive follow-up. Results of iodine scan, serum-TG, and additional imaging modalities as well as histology were compared in all patients. RESULTS: 21/490 (4.3%) of patients with PCA and 16/242 (6.6%) with FCA suffered from recurrent disease. 62/490 (12.7%) of patients with PCA and 59/242 (24.4%) with FCA had primary metastatic/progressive disease. 12/21 patients with PCA and 12/16 with FCA showing up with recurrent disease had a negative iodinescan. 11/21 of patients with PCA and 4/16 with FCA and tumor recurrence had negative serum-TG levels. 14/62 patients with PCA and 14/59 with FCA presenting with primary metastatic/progressive disease had negative iodinescan. 14/62 patients with PCA and 6/59 with FCA had negative serum-TG. CONCLUSION: The prevalence of iodine-negative recurrent/metastatic disease is in accordance to the literature, whereas the prevalence of TG-negative recurrent/metastatic was noted higher than reported previously. Thus, the commonly used follow-up scheme of DTC is confirmed. However, iodine scan should be regularly performed in patients with high risk of recurrence.

[Lymph scintigraphy and pre- and intraoperative gamma probe measurements for localization of sentinel lymph nodes (SLN) in breast cancer]. / Lymphszintigraphie sowie prä- und intraoperative Sondenmessung zur Darstellung des Sentinel Lymph Node (SLN) beim Mammakarzinom.

UNLABELLED: Aim of this study was to prove the clinical value of nuclear medicine procedures to detect the sentinel lymph node (SLN) for SLN biopsy. METHODS: In 132 patients with breast cancer we performed lymph scintigraphy of the breast as well as both pre- and intraoperative gamma probe measurements correlating the results with the findings of histopathology. RESULTS: SLN were detectable in 62 of 110 patients according to a sensitivity of 56% when scanning was performed only at 1-2 h p.i. while the sensitivity increased to 86% (19 of 22 pts.) if sequential images were acquired up to 2 h p.i. One or more SLN were identified by a hand-held gamma probe transcutaneously prior to surgery in 96% (113 of 118 pts.) of the patients who showed up with no clinically suspected lymph node metastases. Intraoperatively, in additionally 2 patients the SLN could be found resulting in a sensitivity of 97% (115 of 118 pts.). In only 3 patients with clinically no tumor spread to axillary lymph nodes no SLN could be identified by the probe. Skip lesions, i.e. lymph node metastases in patients with tumor-free SLN, occurred in 2 cases: due to SLN biopsy in these patients lymph node staging was false negative compared to conventional staging by means of axillary lymph node dissection. CONCLUSION: The results demonstrate a high preoperative detection rate of SLN in patients with breast cancer using lymph scintigraphy and gamma probe measurements. Thus, nuclear medicine is capable of providing the basic requirements for SLN biopsy in the daily routine.

FDG PET detection of unknown primary tumors.

UNLABELLED: The management of patients presenting with metastases of unknown primary origin remains a clinical challenge despite a large variety of imaging modalities. The aim of this study was to evaluate FDG PET in detecting the sites of primary cancer in these patients. METHODS: Fifty-three patients with metastatic cervical adenopathy (n = 44) or extracervical metastases (n = 9) of unknown primary origin were included after extensive but inconclusive conventional diagnostic work-up. Patients received 370 MBq FDG (10 mCi) intravenously, and whole-body images were acquired at 60 min after injection. Clinical, surgical, and histopathologic findings and complete correlative imaging were used to assess the results. RESULTS: In 27 of 53 patients FDG PET showed focal tracer accumulations corresponding to potential primary tumor sites located in the lungs (n = 12), the palatine tonsil (n = 5), the salivary glands (n = 2), the nasopharynx (n = 1), the oropharynx (n = 3), the maxillary sinus (n = 1), and the larynx (n = 1). Moreover, in 2 patients FDG PET revealed lesions suspected to be tumors in the breast and the ileocolonic area. In 20 (37.8%) of these 53 patients FDG PET was true-positive, identifying the primary tumor in the lungs (n = 10), the head and neck region (n = 8), the breast (n = 1), and the ileocolonic area (n = 1). In 6 of 27 patients FDG PET was false-positive, predominantly identifying suspicious areas in the palatine tonsil (n = 3). One patient denied further diagnostic work-up after PET; thus, positive PET could not be evaluated. In 26 of 53 patients PET did not reveal lesions suspected to be the primary. However, primary tumors were not found in these patients at clinical follow-up. CONCLUSION: FDG PET is a valuable diagnostic tool in patients with cancer of unknown primary because it imaged unknown primary tumors in about one third of all patients investigated. In addition, FDG PET assists in both guiding biopsies for histologic evaluation and selecting the appropriate treatment protocols for these patients.

[Efficacy of radiation synovectomy in degenerative inflammatory and chronic inflammatory joint diseases]. / Wirksamkeit der Radiosynoviorthese bei degenerativ-entzündlichen und chronisch-entzündlichen Gelenkerkrankungen.

AIM: Effect of radiosynovectomy (RS) should be evaluated both by subjective and objective parameters in patients with osteoarthritis and in patients with inflammatory joint disorders not caused by rheumatoid arthritis. METHODS: A total of 98 joints in 61 patients were investigated. Patients were divided into two groups. The first group included 35 patients with therapy-resistant effusions caused by severe osteoarthritis (46 joints). The second group consisted of 26 patients (52 joints) with ankylosing spondylitis, reactive arthritis, undifferentiated spondylarthropathy, psoriatic arthritis, pigmented villo-nodular synovitis, and recurrent synovitis following surgery. Effect of RS was evaluated by a standardized questionnaire and quantified by T/B-ratios derived from blood pool images prior to and after RS. RESULTS: Within the first patient group suffering from osteoarthritis, 40% showed a good or excellent improvement of clinical symptoms, 51% were unchanged, and in 9% symptoms worsened. Similar results were found in the second patient group. The majority of unchanged results were small finger joints. In contrast, wrist and knee joints showed a better improvement. Good correlation between results of bone scan and patients subjective impression was found in 38% and 67% in the first and the second patient group, respectively. CONCLUSION: Radiosynovectomy might be an effective treatment in osteoarthritis and inflammatory joint disorders not caused by rheumatoid arthritis.

Radioprotection of salivary glands by amifostine in high-dose radioiodine treatment. Results of a double-blinded, placebo-controlled study in patients with differentiated thyroid cancer.

BACKGROUND AND PURPOSE: Parenchymal impairment of salivary glands following high-dose radioiodine treatment is a well-known side effect in general caused by free radicals. Therefore, the radioprotective effect of the radical scavenger amifostine was evaluated prospectively in patients receiving high-dose radioiodine treatment. PATIENTS AND METHODS: Parenchymal function was assessed by quantitative salivary gland scintigraphy performed in 50 patients with differentiated thyroid cancer prior to and 3 months after high-dose radioiodine treatment with either 3 GBq 131I (n = 21) or 6 GBq 131I (n = 29) in a double-blinded, placebo-controlled study. Twenty-five patients treated with 500 mg/m2 amifostine intravenously prior to high-dose radioiodine treatment were compared to 25 control patients receiving physiological saline solution. Xerostomia was graded according to WHO-criteria. RESULTS: In 25 control patients high-dose radioiodine treatment significantly (p < 0.001) reduced parenchymal function of parotid and submandibular glands by 40.2 +/- 14.1% and 39.9 +/- 15.3%, respectively. Nine out of these 25 patients developed Grade I and 2 Grade II xerostomia. In contrast, in 25 amifostine-treated patients there was no significant (p = 0.691) decrease in parenchymal function following high-dose radioiodine treatment, and xerostomia did not occur in any of them. CONCLUSION: Parenchymal damage of salivary glands induced by high-dose radioiodine treatment can be significantly reduced by amifostine which may improve quality of life of patients with differentiated thyroid cancer.

Pregnancy testing before high-dose radioiodine treatment: a case report.

This case emphasizes that negative urine pregnancy testing and a written declaration of the patient are not sufficient to safely exclude an early pregnancy. Serum pregnancy testing inherently has a diagnostic gap of about 1 wk following conception. We recommend sufficient contraception at least 1 mo before radioiodine treatment in women of childbearing age.

Radioprotection of salivary glands by S-2-(3-aminopropylamino)-ethylphosphorothioic (amifostine) obtained in a rabbit animal model.

BACKGROUND: Impairment of salivary gland function following high-dose radioiodine treatment (HDRIT) is a well-recognized side effect of the treatment. Because differentiated thyroid cancer has an excellent prognosis, reduction of long-term side-effects is mandatory. Therefore, the aim of this study was to investigate the radioprotective effect of amifostine in a rabbit animal model. METHODS: Salivary gland scintigraphy was performed in a total of 16 New Zealand White rabbits. Uptake of 99-Tc-pertechnetate was calculated in percentage of injected activity as a quantitative measure of both salivary gland and thyroid function. Reproducibility of salivary gland scintigraphy was evaluated in one rabbit without any intervention. Fifteen rabbits were studied prior to and up to 6 months after high-dose radioiodine treatment applying 2 GBq 131I. Ten animals received 200 mg/kg amifostine prior to high-dose radioiodine therapy, and 5 served as controls. Salivary glands were examined histopathologically. RESULTS: Variation coefficient of parenchymal function was less than 3.8% in salivary glands. Prior to HDRIT, thyroid uptake was 0.417+/-0.373% and 0.421+/-0.241% in control and amifostine-treated rabbits, respectively. Four weeks after HDRIT, complete ablation of the thyroid was achieved in both groups. Prior to HDRIT, uptake of 99mTc-pertechnetate in salivary glands of five control rabbits was not significantly different from ten amifostine-treated rabbits. In control rabbits 6 months after HDRIT, parenchymal function was reduced significantly (p < 0.0001) by 75.3+/-5.3% and 53.6+/-17.4% in parotid and submandibular glands, respectively. In contrast, in amifostine-treated rabbits, parenchymal function was reduced by 10.6+/-3.4% and 6.5+/-4.3% (p > 0.05) in parotid and submandibular glands, respectively. Histopathologically, marked lipomatosis was observed in control animals but was negligible in amifostine-treated animals. CONCLUSION: Parenchymal damage in salivary glands induced by high-dose radioiodine treatment can be significantly reduced by amifostine in this rabbit animal model. This corresponds to data obtained in patients with differentiated thyroid cancer.

[F-18 FDG PET for detection of occult primary tumor in patients with lymphatic metastases of the neck region]. / F-18-FDG-PET zur Detektion des okkulten Primärtumors bei Patienten mit Lymphknotenmetastasen der Halsregion.

BACKGROUND: The occult primary tumor remains an important diagnostic problem in patients with lymph node metastases despite a large variety of imaging modalities. Therefore, the aim of our study was to evaluate the impact of F-18-FDG-positron-emission-tomography (PET) in these patients. METHODS: The study group included a total of 28 patients aged 39 to 84 years with cervical lymph node metastases of a histologically confirmed squamous cell carcinoma (n = 24) or an undifferentiated carcinoma (n = 4). All patients received 370 MBq F-18-FDG intravenously, and whole-body images were acquired at 60 min p.i. with an ECAT EXACT 47 (921) (Siemens, CTI). All lesions were evaluated either by histology or by CT/MRI. RESULTS: In 12 patients PET did not reveal suspected tumorous lesions. In contrast in 16/28 patients PET showed focal tracer accumulations corresponding to potential primary tumor sites located in the lungs (n = 7), in the region of the tonsilla palatina (n = 5), in the submandibular gland (n = 1), in the nasopharynx (n = 1), in the larynx (n = 1), or at the base of the tongue (n = 1). In nine out of these 16 patients, the primary was confirmed in the lungs in 5 patients, in the larynx, at the base of the tongue, in the nasopharynx, and the tonsilla palatina in one patient each, respectively. Moreover, in 6 out of 16 patients, PET was false-positive. One patient refused further evaluation of PET findings. CONCLUSIONS: In approximately one third of all patients, PET detected the primary tumor site, which significantly influenced further therapeutic procedures. Thus, F-18-FDG-PET may be a valuable diagnostic tool in the detection of the primary tumor in patients with cervical lymph node metastases.

Clinical value of 24-hour delayed imaging in somatostatin receptor scintigraphy for meningioma.

UNLABELLED: Somatostatin receptor scintigraphy (SRS) using 111In-octreotide has proven useful in patients suspected of having meningiomas. Delayed imaging is regularly performed up to 24 h postinjection. However, this procedure is time consuming and expensive. Therefore, we investigated whether 24-h imaging may be omitted in these patients. METHODS: After clinical examination and standard MRI, 71 patients were suspected of having 92 meningioma lesions. Before surgery, all patients underwent SRS after intravenous injection of 200 MBq (5.4 mCi) 111In-octreotide. Planar whole-body images were obtained at 10 min and 1, 4 and 24 h, and SPECT was performed at 4 and 24 h. Results of SRS in all lesions were evaluated with respect to histology and time of image acquisition. RESULTS: SRS yielded 58 true-positive, 20 true-negative and 14 false-negative results, with the false-negatives all less than 5 mL (2.3+/-2.1 mL) in volume. In 52 of 58 true-positive lesions (89.7%), diagnosis could be established by 4-h imaging without further information by 24-h imaging. In 10 of the 52 lesions, SPECT was necessary to confirm planar findings. Imaging at 24 h was necessary in only 6 of 58 true-positive lesions (10.3%): 3 patients who had intracranial relapse of meningioma (volume < 5 mL) and 3 who had spinal meningioma. Thus, a diagnosis of intracranial meningioma could be established in 52 of 55 lesions (95%) using a 4-h imaging protocol. CONCLUSION: With a 4-h acquisition protocol that includes SPECT imaging, SRS yields sufficient information in patients suspected of having intracranial meningiomas. Delayed imaging at 24 h is recommended only for patients who have small meningiomas (volume < 5 mL), spinal localizations or negative SRS at 4 h.

Lymphoscintigraphy in tumors of the head and neck using double tracer technique.

UNLABELLED: Knowledge of possible lymphatic drainage may facilitate planning of surgery for patients with head and neck tumors. Therefore, the aim of this study was to present a method of lymphoscintigraphy with special attention to an accurate correlation of lymphatic drainage to anatomic regions. METHODS: Lymphoscintigraphy was performed using a double tracer technique before surgery in a total of 75 patients with squamous cell carcinoma of the head and neck. All patients received 100 MBq 99mTc-colloid at three to four peritumoral sites. A perchlorate solution (2 mL) was given orally to block salivary glands and the thyroid gland. Patients received 50 MBq 99mTc-pertechnetate intravenously for body contouring 20 min postinjection. Planar images were obtained over 5 min each, at 30 min and 4 h postinjection from anterior, right lateral and left lateral views with a large-field-of-view gamma camera. Lymphatic drainage was assessed by visual inspection and assigned to six cervical compartments. RESULTS: Neither the salivary glands nor the thyroid gland were seen in any of the patients. In 22 of 75 patients (29.3%), the injection site was the only focal tracer uptake seen. In contrast, lymphatic drainage was identified in the remaining 53 patients (70.7%), and lymph nodes could be assigned easily to the six cervical compartments. Of 75 patients, 36 (48%) exhibited ipsilateral lymphatic drainage. In addition, 17 patients (22.7%) with unilateral tumor showed bilateral (n = 12), contralateral (n = 2) or retropharyngeal (n = 3) lymphatic drainage. In 3 of these 17 patients, bilateral lymph node metastases were proven. A subgroup of 12 patients (16%) exhibited N2c nodal status, despite a unilateral localized primary tumor. In 3 of these 12 patients, surgery was extended as a result of scintigraphic findings from unilateral toward bilateral neck dissection, and histology confirmed nodal involvement in these patients. CONCLUSION: Lymphoscintigraphy using the double tracer technique allows an accurate correlation of lymphatic drainage to the six cervical compartments. This may provide the basis for a re-evaluation of its impact in treatment planning of patients with head and neck tumors.

Quantitative salivary gland scintigraphy.

OBJECTIVE: Uptake of 99mTc-pertechnetate in salivary glands reflects intact salivary gland parenchyma. However, no standardized protocol for an accurate quantification of parenchymal function has been established so far. METHODS: In this paper we report on a validated acquisition protocol supplying a normal database for standardized quantitative salivary gland scintigraphy. RESULTS: The major advantage of salivary gland scintigraphy, as compared to other imaging modalities, is that both parenchymal function and excretion fraction of all four major salivary glands (i.e., parotid and submandibular glands) can be simultaneously quantified with a single intravenous injection. CONCLUSION: Quantitative salivary gland scintigraphy is demonstrated to be a suitable imaging modality for research applications in evaluating the effects of radioprotective drugs on salivary glands. Salivary gland scintigraphy is easy to perform, reproducible and well-tolerated by the patient.