Contemporary Multimodality Imaging of Primary Hyperparathyroidism.

Primary hyperparathyroidism (PHPT) is a disorder characterized by hypercalcemia and an elevated or inappropriately normal parathyroid hormone level. Classic features include bone pain, fractures, renal impairment, nephrolithiasis, and mental disturbance. However, most cases of PHPT are now asymptomatic at diagnosis or associated with nonspecific neurocognitive changes. The most frequent cause of PHPT is a solitary adenoma that secretes parathyroid hormone without the normal suppressive effect of serum calcium. A smaller number of cases can be attributed to multigland disease. Parathyroidectomy is curative and is considered for nearly all affected patients. Although PHPT is primarily a clinical and biochemical diagnosis, imaging is key to the localization of adenomas, which can lie in conventional locations adjacent to the thyroid gland or less commonly at ectopic sites in the neck and mediastinum. In addition, accurate localization facilitates the use of a minimally invasive or targeted surgical approach. Frequently used localization techniques include US, parathyroid scintigraphy, and four-dimensional CT. Second- and third-line modalities such as MRI, PET/CT, and selective venous sampling with or without parathyroid arteriography can increase confidence before surgery. These localization techniques, along with the associated technical aspects, relative advantages, and drawbacks, are described. Local expertise, patient factors, and surgeon preference are important considerations when determining the type and sequence of investigation. A multimodality approach is ultimately desirable, particularly in challenging scenarios such as multigland disease, localization of ectopic adenomas, and persistent or recurrent PHPT. Online supplemental material is available for this article. ©RSNA, 2022.

The Vanishing Adrenal Glands: A Transient Regression of Adrenal Lymphoma After a Single Dose of 1 mg Dexamethasone.

OBJECTIVE: Dexamethasone is a known treatment for lymphoma, but the potency and rapidity of its effect have not been recognized. We present a case of bilateral adrenal lymphoma that significantly reduced in size after a single dose of dexamethasone. METHODS: We present the clinical course and investigations, including adrenocorticotropic hormone, cortisol, short synacthen test, computed tomography (CT), and adrenal biopsy results. RESULTS: A 52-year-old man had a fall and was incidentally found to have bilateral adrenal masses (left, 6 cm; right, 5 cm) on CT. His adrenal function tests included plasma metanephrines (normetanephrine, 830 pmol/L [normal, <1180]; metanephrine, <100 pmol/L [<510]; 3-methoxytyramine, <100 pmol/L [<180]); aldosterone, 270 pmol/L( 90-700); and random cortisol, 230 nmol/L (160-550). An overnight dexamethasone suppression test with 1 mg of dexamethasone showed cortisol of <28 nmol/L (0-50). A repeat CT scan 8 days thereafter showed adrenal masses of 4.5 and 3.5 cm on the left and right, respectively. He had a follow-up CT scan 3 months later that showed adrenal lesions measuring 8 cm (left) and 9 cm (right). He subsequently presented with fatigue and dizziness. Morning cortisol of 201 nmol/L (160-550) with adrenocorticotropic hormone of 216 ng/L (10-30) indicated primary adrenal insufficiency. Mineralocorticoid and glucocorticoid replacement therapy commenced. An adrenal biopsy showed abnormal enlarged B cells, consistent with a diagnosis of diffuse large B-cell lymphoma. CONCLUSION: A diagnosis of lymphoma should be considered when adrenal lesions shrink following even a single low dose of dexamethasone administered as a part of a diagnostic test.

A combination of surgery, theranostics, and liquid biopsy - a personalised oncologic approach to treatment of patients with advanced metastatic neuroendocrine neoplasms.

Rationale: Neuroendocrine neoplasia (NEN) of small bowel (SBNEN) frequently present with metastatic disease. Theranostics (molecular imaging followed by targeting therapy) allow for personalised medicine. Liquid biopsies enable precise identification of residual disease and real-time monitoring of therapeutic response. Our aim was to determine the clinical utility of a combination of surgery, theranostics, and a multigene blood measurement in metastasised SBNEN. Methods: Inclusion criteria were SBNEN, G1/G2 NEN, initial tumour diagnosis, stage IV NEN, positivity on 68Ga somatostatin analogue PET/CT, eligible for surgery, and 177Lu peptide receptor radionuclide therapy (PRRT). Blood samples for NETest were collected longitudinally. Progression-free survival (PFS) and overall survival (OS) were calculated. NETest results were assessed prior to surgery and during clinical follow-up. Results: A surgical cohort of 39 SBNEN patients met eligibility criteria. Thirty-two patients underwent ileal resection and 7 right hemicolectomy. The mean number of 177Lu PRRT cycles was 4. Mortality was nil. Surgical morbidity was 10.3%. Transient grade 1/2 toxicity occurred in 41% (PRRT). NETest scores (n=9 patients) decreased in 100% following treatment and correlated with diminished tumour volume and disease stabilization following surgery and PRRT. Median follow-up: 78 months. Median PFS and OS: 42.7 and 110 months, respectively. Progression-free survival at 1-, 3-, and 5-years was 79.4%, 57.1% and 40.5%, respectively. Overall survival at 1-, 3-, and 5-years was 97.4%, 97.4%, and 94.1%, respectively. Conclusions: Surgery combined with 177Lu PRRT is safe and provides favourable PFS and OS in selected patients with advanced SBNEN. Liquid biopsy (NETest) has the potential to accurately delineate disease status.

European Reference Network for Rare Vascular Diseases (VASCERN) position statement on cerebral screening in adults and children with hereditary haemorrhagic telangiectasia (HHT).

Hereditary haemorrhagic telangiectasia (HHT) is a multisystemic vascular dysplasia inherited as an autosomal dominant trait. Approximately 10 % of patients have cerebral vascular malformations, a proportion being cerebral arteriovenous malformations (AVMs) and fistulae that may lead to potentially devastating consequences in case of rupture. On the other hand, detection and treatment related-risks are not negligible, and immediate. While successful treatment can be undertaken in individual cases, current data do not support the treatment of unruptured AVMs, which also present a low risk of bleeding in HHT patients. Screening for these AVMs is therefore controversial.Structured discussions, distinctions of different cerebrovascular abnormalities commonly grouped into an "AVM" bracket, and clear guidance by neurosurgical and neurointerventional radiology colleagues enabled the European Reference Network for Rare Vascular Disorders (VASCERN-HHT) to develop the following agreed Position Statement on cerebral screening:1) First, we emphasise that neurological symptoms suggestive of cerebral AVMs in HHT patients should be investigated as in general neurological and emergency care practice. Similarly, if an AVM is found accidentally, management approaches should rely on expert discussions on a case-by-case basis and individual risk-benefit evaluation of all therapeutic possibilities for a specific lesion.2) The current evidence base does not favour the treatment of unruptured cerebral AVMs, and therefore cannot be used to support widespread screening of asymptomatic HHT patients.3) Individual situations encompass a wide range of personal, cultural and clinical states. In order to enable informed patient choice, and avoid conflicting advice, particularly arising from non-neurovascular interpretations of the evidence base, we suggest that all HHT patients should have the opportunity to discuss knowingly brain screening issues with their healthcare provider.4) Any screening discussions in asymptomatic individuals should be preceded by informed pre-test review of the latest evidence regarding preventative and therapeutic efficacies of any interventions. The possibility of harm due to detection of, or intervention on, a vascular malformation that would not have necessarily caused any consequence in later life should be stated explicitly.We consider this nuanced Position Statement provides a helpful, evidence-based framework for informed discussions between healthcare providers and patients in an emotionally charged area.

A rare cause of severe Cushing's syndrome.

SUMMARY: Ectopic adrenocorticotropic hormone (ACTH) production is an uncommon cause of Cushing's syndrome and, rarely, the source can be a phaeochromocytoma. A 55-year-old man presented following an episode of presumed gastroenteritis with vomiting and general malaise. Further episodes of diarrhoea, joint pains and palpitations followed. On examination, he was hypertensive with no clinical features to suggest hypercortisolaemia. He was subsequently found to have raised plasma normetanephrines of 3.98 nmol/L (NR <0.71) and metanephrines of 0.69 nmol/L (NR <0.36). An adrenal CT showed a 3.8 cm right adrenal nodule, which was not MIBG-avid but was clinically and biochemically consistent with a phaeochromocytoma. He was started on alpha blockade and referred for right adrenalectomy. Four weeks later, on the day of admission for adrenalectomy, profound hypokalaemia was noted (serum potassium 2.0 mmol/L) with non-specific ST-segment ECG changes. He was also diagnosed with new-onset diabetes mellitus (capillary blood glucose of 28 mmol/L). He reported to have gained weight and his skin had become darker over the course of the last 4 weeks. Given these findings, he underwent overnight dexamethasone suppression testing, which showed a non-suppressed serum cortisol of 1099 nmol/L. Baseline serum ACTH was 273 ng/L. A preliminary diagnosis of ectopic ACTH secretion from the known right-sided phaeochromocytoma was made and he was started on metyrapone and insulin. Surgery was postponed for 4 weeks. Following uncomplicated laparoscopic adrenalectomy, the patient recovered with full resolution of symptoms. LEARNING POINTS: Phaeochromocytomas are a rare source of ectopic ACTH secretion. A high clinical index of suspicion is therefore required to make the diagnosis. Ectopic ACTH secretion from a phaeochromocytoma can rapidly progress to severe Cushing's syndrome, thus complicating tumour removal. Removal of the primary tumour often leads to full recovery. The limited literature suggests that the presence of ectopic Cushing's syndrome does not appear to have any long-term prognostic implications.

Patients with in-situ metallic coils and Amplatzer vascular plugs used to treat pulmonary arteriovenous malformations since 1984 can safely undergo magnetic resonance imaging.

OBJECTIVE: To examine the MRI safety of metallic coils and Amplatzer vascular plugs. Currently, concern regarding MR safety of devices used to treat pulmonary arteriovenous malformations (PAVMs) causes delays in performing emergency MRI in patients presenting with acute neurological symptoms. METHODS: A retrospective audit was performed on all patients who underwent PAVM embolization at Hammersmith Hospital, London UK between 1984 and 2017. Outcomes of all MRI studies performed at our institution were recorded. In addition, known outcomes of all known MRI studies performed on patients treated with the earliest steel coils (1984-1995) were recorded. RESULTS: At our institution, 20 patients underwent 1.5 T MRI after the insertion of 100 steel coils (15.5 - 28.6, median 22 years later), 140 coils designated MR-conditional (0.42 - 12.7, median 9.3 years later), and 54 MRI-conditional Amplatzer vascular plugs (0.17 - 8.0, median 0.75 years later), many in combination. The majority of scans were for cerebral indications, but other body regions scanned included spinal, thoracic, and pelvic regions. No adverse events were reported. Similarly, there were no adverse events in any MR scan known to have been performed in other institutions in seven further patients treated with the earliest steel coils (1984-1995). Again, the majority of scans were for cerebral indications. CONCLUSION: The findings demonstrate MR safety at 1.5 T of all PAVM embolization devices inserted in a main UK centre since inception in 1984. ADVANCES IN KNOWLEDGE: MRI of patients who have had PAVMs treated by embolization can be implemented without contacting specialist pulmonary arteriovenous malformation treatment centres for approval.

Radioembolisation with 90Y microspheres for neuroendocrine liver metastases: an institutional case series, systematic review and meta-analysis.

BACKGROUND: Neuroendocrine liver metastases are clinically challenging due to their frequent disseminated distribution. This study aims to present a British experience with an emerging modality, radioembolisation with yttrium-90 labelled microspheres, and embed this within a meta-analysis of response and survival outcomes. METHODS: A retrospective case series of patients treated with SIR-Spheres (radiolabelled resin microspheres) was performed. Results were included in a systematic review and meta-analysis of published results with glass or resin microspheres. Objective response rate (ORR) was defined as complete or partial response. Disease control rate (DCR) was defined as complete/partial response or stable disease. RESULTS: Twenty-four patients were identified. ORR and DCR in the institutional series was 14/24 and 21/24 at 3 months. Overall survival and progression-free survival at 3-years was 77.6% and 50.4%, respectively. There were no grade 3/4 toxicities post-procedure. A fixed-effects pooled estimate of ORR of 51% (95% CI: 47%-54%) was identified from meta-analysis of 27 studies. The fixed-effects weighted average DCR was 88% (95% CI: 85%-90%, 27 studies). CONCLUSION: Current data demonstrate evidence of the clinical effectiveness and safety of radioembolisation for neuroendocrine liver metastases. Prospective randomised studies to compare radioembolisation with other liver directed treatment modalities are needed.

Is it Time for a Specific Undergraduate Interventional Radiology Curriculum?

PURPOSE: Interventional radiology (IR) is traditionally underrepresented in undergraduate medical curricula. Final-year medical students ought to be familiar with some common IR procedures in order to make adequate referrals and work-up patients appropriately. We evaluated the knowledge of final-year medical students on common IR procedures and compared it with their knowledge of other specialties. MATERIALS AND METHODS: A fourteen-question, single-best-answer questionnaire assessing the knowledge of IR procedures and other minimally invasive non-IR procedures was administered to a group of final-year medical students. Paired two-tailed student's t test was used to compare knowledge across specialties. RESULTS: Fifty-one questionnaires were administered and returned. No student answered all questions correctly. The median score was 5/11. The best-answered question was on coronary intervention followed by neurosurgical procedures. The average score for IR procedures was 38% versus 57% for non-IR procedures (P < 0.0005). While most students had come across IR previously, 70% would like further exposure. We also accessed the undergraduate curricula of five London Medical Schools; all five have a radiology curriculum, but only one has a dedicated IR section. CONCLUSION: Medical students' lack of IR exposure translates into a lack of appreciation of the role of the specialty. We propose the introduction of a specific undergraduate IR curriculum to bridge this knowledge gap.

Role of US Contrast Agents in the Assessment of Indeterminate Solid and Cystic Lesions in Native and Transplant Kidneys.

Ultrasonography (US) is often the initial imaging modality employed in the evaluation of renal diseases. Despite improvements in B-mode and Doppler imaging, US still faces limitations in the assessment of focal renal masses and complex cysts as well as the microcirculation. The applications of contrast-enhanced US (CEUS) in the kidneys have dramatically increased to overcome these shortcomings with guidelines underlining their importance. This article describes microbubble contrast agents and their role in renal imaging. Microbubble contrast agents consist of a low solubility complex gas surrounded by a phospholipid shell. Microbubbles are extremely safe and well-tolerated pure intravascular agents that can be used in renal failure and obstruction, where computed tomographic (CT) and magnetic resonance (MR) imaging contrast agents may have deleterious effects. Their intravascular distribution allows for quantitative perfusion analysis of the microcirculation, diagnosis of vascular problems, and qualitative assessment of tumor vascularity and enhancement patterns. Low acoustic power real-time prolonged imaging can be performed without exposure to ionizing radiation and at lower cost than CT or MR imaging. CEUS can accurately distinguish pseudotumors from true tumors. CEUS has been shown to be more accurate than unenhanced US and rivals contrast material-enhanced CT in the diagnosis of malignancy in complex cystic renal lesions and can upstage the Bosniak category. CEUS can demonstrate specific enhancement patterns allowing the differentiation of benign and malignant solid tumors as well as focal inflammatory lesions. In conclusion, CEUS is useful in the characterization of indeterminate renal masses and cysts.

Endovascular treatment of thoracic aortic aneurysms with a short proximal landing zone using scalloped endografts.

BACKGROUND: The suitability of the proximal landing zone remains one of the main limitations to thoracic endovascular aortic repair (TEVAR). The advent of custom-made scalloped stent grafts widens the endovascular options for patients with challenging anatomy. The objective of this study was to present our early and midterm results of custom-made scalloped thoracic stent grafts. METHODS: Prospectively acquired data relating to patient demographics, procedure details, clinical outcome, and complications were analyzed. In addition, we analyzed preoperative and postoperative computed tomography scans to evaluate aneurysm morphology, graft placement, side-vessel patency, and endoleaks. RESULTS: Twenty-one patients with a median age of 71 years (range, 35-81 years) underwent custom-made scalloped TEVAR, eight of whom had a concomitant hybrid repair. Procedural success was achieved in all cases. Proximal seal was achieved in all cases, with no type I endoleaks. There were no cases of retrograde dissection and no conversions to open repair. The median follow-up period was 36 weeks (range, 3-183 weeks). Two patients died in the hospital. Three patients suffered a stroke. Three patients had a type II endoleak, one of whom had significant sac enlargement requiring reintervention. One patient had a type III endoleak requiring reintervention. There were no cases of graft migration. CONCLUSIONS: Our midterm results show that custom-made scalloped TEVAR is an acceptable treatment of thoracic aortic aneurysms with a short proximal landing zone. Longer term outcome data are required to establish wider use of scalloped thoracic endografts.

Changes in renal function in elderly patients following intravenous iodinated contrast administration: a retrospective study.

Background. Contrast-induced nephropathy (CIN) is a recognised complication of intravascular administration of iodinated contrast media (ICM). Previous studies suggest a higher incidence in the elderly, but no large study has assessed this to date. We set out to assess changes in creatinine in elderly inpatients following computed tomography (CT) examination and compare those who received intravenous contrast to those who did not. Methods. Using the Radiology Information System in two teaching hospitals, inpatients over the age of seventy who had a CT examination and a baseline creatinine were identified and their follow-up creatinine levels were analysed. Elderly inpatients who underwent a noncontrast CT over the same period were used as controls. Results. 677 elderly inpatients who received ICM were compared with 487 controls. 9.2% of patients who received ICM developed acute kidney injury (AKI) compared to 3.5% of inpatient controls (P < 0.0001). Patients with higher baseline eGFR had a higher incidence of post-CT AKI. Conclusions. The incidence of post-CT AKI is higher in patients who received IV ICM compared to those who did not; the difference may be partly attributable to contrast-induced nephropathy. This suggests that the incidence of CIN in the elderly may not be as high as previously thought.

Spinal extradural solitary fibrous tumor with retiform and papillary features.

We report a 66-year-old man with a spinal, extradural solitary fibrous tumor showing unique retiform and papillary architecture. The patient presented in May 2008 with worsening right-sided lower back pain and urinary frequency. Magnetic resonance imaging of the spine documented a heterogeneously enhancing dumbbell-shaped extradural lesion causing cord compression at T11/12 level. The tumor extended to the paravertebral soft tissue and invaded the right adjacent vertebral pedicles and laminae. An angiogram showed prominent vascular supply mainly from the right T11 radicular artery. The patient underwent surgery to relieve cord compression in May 2008 and a second operation following embolization with coils in October 2009. No recurrence was observed at the last neuroimaging follow-up in June 2012. The tumor was composed of vimentin, CD34, Bcl-2, and CD99-positive rounded or slightly elongated cells with scant cytoplasm and oval to spindle nuclei. Several pseudovascular spaces reminiscent of the rete testis were present, and several of them contained papillary projections. Cytologic atypia was minimal, and mitotic activity was low. Focal infiltration of the paraspinal adipose tissue was seen at microscopic level. To our knowledge, retiform and papillary features have never been reported in a solitary fibrous tumor.