Novel Use of Contrast-enhanced Ultrasound in the Pretreatment Planning Prior to Endovascular Repair of Endoleak after Endovascular Aortic Aneurysm Repair in a Patient with Chronic Renal Insufficiency: A Case Report and Literature Review.

Endoleaks are a common complication in patients who have undergone endovascular stent-graft repair of abdominal aortic aneurysms. The management of these complications depends on the type of endoleak seen at follow-up imaging, with embolization being generally accepted treatment option for Type 2 endoleaks in certain clinical scenarios. Endovascular endoleak embolization can be arduous, time-consuming, and require large amounts of iodinated contrast during the angiographic procedure. This article describes a novel use of contrast-enhanced ultrasound as a clinical problem-solving tool in the preprocedural planning of patient undergoing an endoleak embolization.

Comparison of Clinical Performance of VectorFlow and Palindrome Symmetric-Tip Dialysis Catheters: A Multicenter, Randomized Trial.

PURPOSE: To compare clinical performance of 2 widely used symmetric-tip hemodialysis catheters. MATERIALS AND METHODS: Patients with end-stage renal disease initiating or resuming hemodialysis were randomized to receive an Arrow-Clark VectorFlow (n = 50) or Palindrome catheter (n = 50). Primary outcome was 90-d primary unassisted catheter patency. Secondary outcomes were Kt/V ([dialyzer urea clearance × total treatment time]/total volume of urea distribution), urea reduction ratio (URR), and effective blood flow (QB). RESULTS: Primary unassisted patency rates with the VectorFlow catheter at 30, 60, and 90 d were 95.5% ± 3.3, 87.2% ± 7.3, and 80.6% ± 9.8, respectively, compared with 89.1% ± 6.2, 79.4% ± 10.0, and 71.5% ± 12.6 with the Palindrome catheter (P = .20). Patients with VectorFlow catheters had a mean Kt/V of 1.5 at 30-, 60-, and 90-day time points, significantly higher than the mean Kt/V of 1.3 among those with Palindrome catheters (P = .0003). URRs were not significantly different between catheters. Catheter QB rates exceeded National Kidney Foundation-recommended thresholds of 300 mL/min at all time points for both catheters and were similar for both catheters (median, 373 mL/min). Catheter failure, ie, poor flow rate requiring guide-wire exchange or removal, within the 90-day primary outcome occurred in 3 VectorFlow subjects and 5 Palindrome subjects (P = .72). Infection rates were similar, with 0.98 infections per 1,000 catheter days for VectorFlow catheters compared with 2.62 per 1,000 catheter days for Palindrome catheters (P = .44). CONCLUSIONS: The 90-day primary patency rates of Palindrome and VectorFlow catheters were not significantly different, and both achieved sustained high QB through 90 day follow-up. However, dialysis adequacy based on Kt/V was consistently better with the VectorFlow catheter versus the Palindrome.

Reporting of Inferior Vena Cava Filter Complications on CT: Impact of Standardized Macros.

OBJECTIVE: The objective of our study was to report the effect of implementing standardized inferior vena cava filter (IVCF) macros on the reporting of IVCFs and filter-related complications in abdominal CT reports. MATERIALS AND METHODS: Retrospective analysis was performed of all abdominal CT reports performed between October 2014 and January 2015 before implementation of IVCF macros (n = 5143). Duplicated examinations and studies requested specifically to evaluate known IVCFs were excluded. In March 2016, normal and abnormal standardized IVCF macros were implemented. Two radiologists reviewed all CT abdominal reports using IVCF macros between March 2016 to July 2016 to assess for missed IVCF complications. RESULTS: Before the implementation of the IVCF macros, 146 of 5143 (2.8%) abdominal CT studies (89 men and 57 women; mean age, 59 years) showed an IVCF. After implementation of IVCF macros, 105 abdominal CT studies using the IVCF macros were analyzed (48 men and 57 women; mean age, 58 years), including 73 normal macros and 32 abnormal macros). The rate of reported caval penetration and filter element-organ interaction improved from 12% (9/73) to 57% (28/49) (p < 0.001) and from 0% (0/53) to 36% (9/25) (p < 0.001) before and after macro implementation, respectively. However, one filter fracture and two filter-associated thrombi were missed when using the IVCF macros. CONCLUSION: Implementation of standardized IVCF macros improves reporting of IVCFs and IVCF-associated complications in abdominal CT reports.

Concurrent Central Venous Stent and Central Venous Access Device Placement Does Not Compromise Stent Patency or Catheter Function in Patients with Malignant Central Venous Obstruction.

PURPOSE: To determine if concurrent placement of a central venous stent (CVS) and central venous access device (CVAD) compromises stent patency or catheter function in patients with malignant central venous obstruction. MATERIALS AND METHODS: CVS placement for symptomatic stenosis resulting from malignant compression was performed in 33 consecutive patients who were identified retrospectively over a 10-year period; 28 (85%) patients had superior vena cava syndrome, and 5 (15%) had arm swelling. Of patients, 11 (33%) underwent concurrent CVS and CVAD placement, exchange, or repositioning; 22 (67%) underwent CVS deployment alone and served as the control group. Types of CVADs ranged from 5-F to 9.5-F catheters. Endpoints were CVS patency as determined by clinical symptoms or CT and CVAD function, which was determined by clinical performance. RESULTS: All procedures were technically successful. There was no difference between the 2 groups in clinically symptomatic CVS occlusion (P = .2) or asymptomatic in-stent stenosis detected on CT (P = .5). None of the patients in the CVS and CVAD group had recurrent clinical symptoms, but 3 (30%) of 10 patients with imaging follow-up had asymptomatic in-stent stenosis. In the control group, 3 (14%) patients had clinically symptomatic CVS occlusion and required stent revision, whereas 4 (21%) of 19 patients with imaging follow-up had asymptomatic in-stent stenosis. During the study, 2 (20%) functional but radiographically malpositioned catheters were identified (0.66 per 1,000 catheter days). CONCLUSIONS: Presence of a CVAD through a CVS may not compromise stent patency or catheter function compared with CVS placement alone.

Significance of Echocardiographically Detected Central Venous Catheter Tip-Associated Thrombi.

PURPOSE: To explore significance, management, and outcomes of central venous catheter (CVC) tip-associated thrombi incidentally detected on echocardiography. MATERIALS AND METHODS: Echocardiogram data from all patients with CVCs from October 2009 to June 2011 were reviewed (N = 170). Patients with CVC tip-associated thrombi were selected (n = 49). Echocardiograms were reviewed for ejection fraction, presence of patent foramen ovale (PFO), presence of other intracardiac shunts, and mean thrombus size. Management decisions, thrombus extension, pulmonary embolism, paradoxical emboli, and stroke within 3 months were recorded. RESULTS: Mean thrombus size was 2.1 cm (range, 0.5-5.7 cm). Of patients with thrombi, 11 (22%) were already on anticoagulation, and there was no change in management. Anticoagulation was started without complications in 17 (35%) patients, the catheter was removed in 4 (8%) patients, and no new treatment was initiated in 17 (35%) patients. Of these 17 patients, 16 (94%) developed no complications. One (6%) patient with a PFO and right-to-left shunt experienced a stroke before PFO closure. After surgical closure of the PFO, the same patient developed catheter tip-associated thrombus without complication. There were no pulmonary emboli, strokes, or other detected embolic phenomena. CONCLUSIONS: In this sample with CVC tip-associated thrombi but without PFO or other intracardiac shunts, no embolic or other complications were detected, regardless of anticoagulation status. These data suggest a benign course for such thrombi and that anticoagulation, catheter removal, thrombectomy, and thrombolysis may be unnecessary when catheter tip-associated thrombi are incidentally detected on echocardiography.

A 16-F Sheath with Endobronchial Forceps Improves Reported Retrieval Success of Long-Dwelling "Closed Cell" Inferior Vena Cava Filter Designs.

PURPOSE: To report results of a 16-F sheath/endobronchial forceps combination in retrieval of "closed cell" inferior vena cava (IVC) filter designs with prolonged dwell times of ≥ 60 days. MATERIALS AND METHODS: Forceps retrieval of selected IVC filters using a 16-F 45-cm sheath was performed in 35 patients (25 women and 10 men). Patients presented with filters that were no longer needed without (n = 10) or with (n = 21) prior failed retrieval, caval thrombosis before lysis (n = 3), and back pain (n = 1). Filter designs included 19 Günther Tulip (54%), 10 Option (29%), and six OptEase (17%). Mean dwell time was 977 days. Imaging characteristics, technical success, fluoroscopy time, and complications were recorded. RESULTS: Filters included 20 tip-embedded, 6 tip-adherent, 4 fractured, and 6 containing thrombus. All were strut and wall-embedded. Initial snare failures occurred in 8 filters because of hook straightening (n = 4), adherent material (n = 2), snare breakage (n = 1), and filter tilt (n = 1). The 16-F sheath/forceps combination was 100% successful in removing filters. In 1 patient, 2 extravascular fragments could not be retrieved. Median fluoroscopy time, excluding 3 extended lysis procedures, was 8 minutes. Minor caval abnormalities, including caval spasm and caval defects, were noted in 17 patients, and filter fracture occurred in 2 patients. No major complications occurred. CONCLUSIONS: A high rate of retrieval for closed cell long-dwelling strut and wall-embedded filters may be achieved using a 16-F sheath/endobronchial forceps combination.

Contemporary Status of Percutaneous Ablation for the Small Renal Mass.

Renal cell carcinoma is the tenth most common malignancy in the USA, with upwards of 61,000 new cases and resulting in more than 14,000 deaths annually. Although partial nephrectomy remains the standard treatment, image-guided nephron-sparing ablative techniques including cryoablation, radiofrequency ablation, and microwave ablation have emerged as treatment options in certain patient populations. Ablative therapies have high technical successes, low tumor recurrence rates, and preserve renal parenchymal volume. The purpose of this article is to provide an update on ablation therapies for small renal masses.

Clinical significance of measuring hepatic venous pressure gradient on transjugular liver biopsy for patients with pre-cirrhotic bridging fibrosis liver disease.

PURPOSE: To demonstrate that patients with pre-cirrhotic bridging fibrosis (Meta-analysis of Histological Data in Viral Hepatitis, METAVIR stage F3) and clinically significant portal hypertension (CSPH, Hepatic Venous Pressure Gradient ≥10 mmHg) experience a higher rate of clinical decompensation than patients without CSPH. MATERIALS AND METHODS: 128 consecutive patients with pathology proven bridging fibrosis without cirrhosis between 2012 and 2019 were reviewed. Inclusion criteria were patients with HVPG measurement obtained during the same outpatient transjugular liver biopsy and clinical follow up of at least two years. Primary endpoint included rate of overall complication related to portal hypertension including evidence of either ascites, presence of varices on imaging or endoscopy, or evidence of hepatic encephalopathy. RESULTS: Among 128 patients with bridging fibrosis (67 females and 61 males; average age 56 years), 42 (33%) and 86 (67%) were with and without CSPH (HVPG ≥10 mmHg). Median follow-up time was 4 years. Rate of overall complication (either ascites, varices or hepatic encephalopathy) in patients with and without CSPH was 36/42 (86%) and 39/86 (45%) (p < .001) respectively. Rate of developing ascites, varices and hepatic encephalopathy in patients with and without CSPH was 21/42 (50%) vs 26/86 (30%) (p = .034), 32/42 (76%) vs 26/86 (30%) (p ≤ .001) and 18/42 (43%) vs 12/86 (14%) (p = .001) respectively. CONCLUSION: Patients with pre-cirrhotic bridging fibrosis and CSPH were associated with higher rates of developing ascites, varices and hepatic encephalopathy. Measuring HVPG during transjugular liver biopsy provides additional prognostic value in anticipating clinical decompensation in patients with pre-cirrhotic bridging fibrosis.

Intra-arterial bevacizumab with blood brain barrier disruption in a glioblastoma xenograft model.

PURPOSE: In this study we investigated the treatment response and survival of intra-arterial (IA) compared to intra-peritoneal (IP) delivery of bevacizumab (BV) in a glioblastoma (GBM) xenograft mouse model. METHODS: 3x10(5) U87-Luc cells were stereotactically implanted into the cortex of 35 nude mice and grouped for treatment (n = 7 in each group): IP saline (group 1), single IP BV (group 2), biweekly IP BV for 3 weeks (group 3), single intra-arterial (IA) BV alone (group 4) and single IA BV with blood brain barrier disruption (BBBD) (group 5). Tumor growth was monitored every 3 to 4 days using bioluminescence imaging (BLI) and survival was analyzed by the Kaplan Meier method. Tumor tissue was analyzed using H&E staining and immunohistochemistry. RESULTS: Based on BLI, BV treated mice showed a delayed tumor growth over time compared to control. Kaplan Meier analysis demonstrated a median survival time of 28 days for group 1,31 days for group 2, 34 days for group 3, 36 days for group 4 and 36 days for group 5 (p < 0.0001). Mice treated with repeated IP BV (p = 0.003) or single IA BV with (p = 0.015) or without (p = 0.005) BBBD showed a significant survival benefit compared to single IP BV treated mice. Post mortem analysis revealed a histological pattern with a more discontinuous border between tumor and mouse brain in the repeated IP BV and single IA BV with or without BBBD treated mice compared to the sharply defined edges of single IP BV treated and control mice. CONCLUSIONS: In this study we showed a significant survival benefit of repeated IP BV and single IA BV with or without BBBD treated mice compared to single IP BV treated and control mice in a U87 xenograft model.

Phase I/II study of oral erlotinib for treatment of relapsed/refractory glioblastoma multiforme and anaplastic astrocytoma.

We evaluated the safety and survival benefits of orally administered erlotinib monotherapy for patients with relapsed/refractory glioblastoma multiforme (GBM) or anaplastic astrocytoma (AA). A dose escalation schedule was administered with a starting dose of 150 mg/day for the first cycle (28 days), followed by 100 mg twice daily for 14 days, and 150 mg twice daily for another 14 days. Assuming no dose limiting toxicities were observed, dosage was maintained at 150 mg BID for 10 more cycles. Disease and tumor responses were assessed after every other cycle; toxicity assessments were conducted for a minimum of 10 weeks. Patients discontinued use of enzyme-inducing anticonvulsants (EIAED) and started non-EIAEDs. Patients with previous erlotinib exposure were ineligible. Eleven patients were enrolled: 8 (73%) GBM; 3 (27%) AA. Adverse events limited study accrual, originally intended to accrue 43 patients. Nine patients (90%) experienced rash within the first 2 cycles: 7 (64%) within cycle 1; 6 (60%) reported diarrhea within the first 2 cycles. Median progress-free survival (PFS) and overall survival (OS) was 1.9 months and 6.9 months. All patients showed disease progression while on the drug. Despite the sample size, the toxicity of erlotinib supersedes any marginal benefit it as a monotherapy for relapsed/refractory GBM/AA.

Laparoscopic and open partial nephrectomy: complication comparison using the Clavien system.

BACKGROUND AND OBJECTIVES: To compare postoperative complications in patients undergoing laparoscopic and open partial nephrectomy using a standardized complication-reporting system and a standardized tumor-scoring system. METHODS: We conducted a retrospective analysis of 189 consecutive patients with nephrometry scores available who underwent elective partial nephrectomy for renal masses. Demographic, perioperative, and complication data were recorded. By using the modified Clavien scale, we graded 30- and 90-day complication rates. RESULTS: 107 patients underwent laparoscopic partial nephrectomy and 82 underwent open partial nephrectomy (N=189). Open partial nephrectomy patients had higher nephrometry scores than laparoscopic patients had (7.1±2.4 vs. 5.6±1.8, P<.001). Surgical and hospitalization times were shorter, and estimated blood loss was lower in the laparoscopic group (P<.001). At 30 days, there were more overall complications in the open group, but more major complications in the laparoscopic group (P>.05). After multivariable logistic regression analysis, only higher body mass index and higher estimated blood loss were predictors of more overall complications. CONCLUSIONS: Laparoscopic partial nephrectomy has the advantages of decreased operative time, lower blood loss, and shorter hospital stay. The complication rate in the laparoscopic group is similar to that in the open group, despite favorable tumor characteristics in the laparoscopic group.

Ultrasound Versus Computed Tomography-Guided Native Parenchymal Kidney Biopsies for Hospitalized Patients: Comparison of Clinical Outcomes and Complications.

ABSTRACT: Percutaneous native kidney biopsies performed with ultrasound (US) or computed tomography (CT) guidance are important in the workup of medical renal disease, with modality choice often dependent on the performing institution, with various complication rates reported. We compared the complication rates and types of complication of US- versus CT-guided native parenchymal renal biopsy among hospitalized patients. One hundred five consecutive inpatient US- and CT-guided native parenchymal renal biopsies performed by radiologists at a tertiary care academic center between 2006 and 2020 were reviewed retrospectively. Complication rates of biopsy were calculated and compared between the 2 modalities. Comparisons with regard to types of complications were made using the Society of Interventional Radiology grading scale, American Society of Anesthesiologists score, and other clinical data. One hundred five hospitalized adult patients (58 women and 47 men; average age, 53 years) underwent native parenchymal kidney biopsy during the study period. Sixty-three (60%) were CT-guided and 42 (40%) were US-guided. Complication rates between CT- versus US-guided biopsies were 40% versus 19% ( P = 0.03), respectively. There were 7 major and 18 minor complications for CT-guided biopsies and 3 major and 5 minor complications for US-guided biopsies. No statistically significant difference was found in preprocedural American Society of Anesthesiologists Classification score, international normalized ratio, platelet count, or body mass index. Computed tomography-guided native parenchymal kidney biopsy was associated with a higher overall complication rate compared with US-guided biopsy for hospitalized patients. Most complications were minor, which required no treatment or additional follow-up.

Iatrogenic Esophagopleural Fistula After the Management of Acute Variceal Hemorrhage With Minnesota Tube Placement.

An esophagopleural fistula (EPF) is a rare condition. EPFs are typically of spontaneous, iatrogenic, or neoplastic origin. A 50-year-old man with hepatitis C and alcoholic cirrhosis presented with a history of recurrent variceal hemorrhage requiring esophageal banding, Minnesota tube placement, and a transjugular intrahepatic portosystemic shunt. His hospital course after esophageal perforation and EPF was complicated by acute respiratory failure and empyema, necessitating intubation and thoracostomy tube placement. To the best of our knowledge, this is the first reported case of EPF secondary to Minnesota tube placement. The EPF completely healed after endoscopic repair.

Cost analysis of intra-arterial versus intra-venous delivery of bevacizumab for the treatment of recurrent glioblastoma multiforme.

Intra-arterial bevacizumab (IA BV) has been recently identified to be safe in the treatment of recurrent GBM. In this study, we sought to perform a cost analysis of IA BV versus IV BV especially also taking account of patient progression free survival (PFS) and overall survival (OS). We show that IA BV is significantly more cost effective than conventional IV therapy.

Endoscopic endonasal transsphenoidal surgery for functional pituitary adenomas.

OBJECT: The purpose of this study was to analyze preoperative predictors of endocrinological remission following endonasal endoscopic resection of therapy-resistant prolactin-, growth hormone (GH)-, and adrenocorticotropic hormone (ACTH)-secreting pituitary adenomas and to establish benchmarks for cure by using the most recent consensus criteria. METHODS: The authors reviewed a prospective database of 86 consecutive functional pituitary adenomas that were resected by a purely endoscopic endonasal transsphenoidal technique. Extent of resection was evaluated on postoperative contrast-enhanced MR imaging. Endocrinological remission was defined according to the most recent consensus criteria. RESULTS: The majority of functional adenomas (62.8%) were classified as macroadenomas (> 1 cm in maximum diameter), and 20.9% of lesions had invaded the cavernous sinus (CS) at the time of surgery. A gross-total resection was achieved in 75.6% of all patients. The rate of endocrinological remission differed between various types of functional adenomas. Cure rates were 92.3% (microadenomas) and 57.1% (macroadenomas) for prolactinomas, 75% (microadenomas) and 40% (macroadenomas) for GH-secreting tumors, and 54.5% (microadenomas) and 71.4% (macroadenomas) for ACTH-secreting tumors. Lower rates of cure occurred in GH-secreting macroadenomas due to a high rate of CS invasion, and in ACTH-secreting adenomas due to a high rate of lesions that were not visible on preoperative MR imaging. Whereas univariate analysis showed that macroadenoma, suprasellar, cavernous extension, or extent of resection correlated with cure, on multivariate analysis, only extent of resection and suprasellar extension predicted cure. One patient developed postoperative meningitis that was complicated by hydrocephalus requiring a ventriculoperitoneal shunt. Two patients developed postoperative panhypopituitarism, and 2 patients suffered from CSF leaks, which were treated with lumbar CSF diversion. CONCLUSIONS: This paper reports benchmarks for endocrinological cure as well as complications in a large series of purely endoscopic pituitary surgeries by using the most recent consensus criteria. The advantages of extended endonasal approaches are most profound in tumors with suprasellar extension and CS invasion.

Hepatic parasitic abscess resistant to traditional anthelmintics: difficulty of diagnosis and treatment of fascioliasis in the USA.

We report a case of human fascioliasis in the USA that encountered many diagnostic uncertainties. Numerous tests available for detection of fascioliasis were utilised but the diagnosis remained elusive. Confounders included three negative stool ova and parasite examinations, positive hepatitis A virus IgM antibody, cross-reactive false-positive Echinococcus IgG antibody, absence of characteristic image findings and unrevealing liver biopsy. Praziquantel was started as empiric treatment for helminth infections, but was ineffective. Due to the rarity of the disease in the USA, serologic testing and triclabendazole were only available from the Centers for Disease Control and Prevention, which led to a delay in diagnosis and treatment.

Rare Variant Hirschsprung Disease Presenting as Large Bowel Obstruction in Adulthood: Hypoganglionosis in the Anorectal Canal.

Hirschsprung disease (HD) is a congenital bowel innervation disorder characterized by the absence of ganglion cells in the neural plexus of the colorectal wall. Variant HD describes a heterogeneous group of intestinal innervation disorders in which clinical presentation resembles HD despite the presence of ganglion cells seen in rectal biopsies. We present the first reported case of a rare variant HD, hypoganglionosis isolated in the anorectal canal, diagnosed in an adult who presented with a long history of constipation and treated with proctosigmoidectomy with coloanal anastomosis. Histopathology showed rare ganglion cells isolated in the anorectal canal.

Contrast-enhanced ultrasound for screening hepatocellular carcinoma: an implemented program at a semi-rural academic center.

PURPOSE: To describe our early experience using a contrast-enhanced ultrasound (CEUS) protocol for surveillance of hepatocellular carcinoma (HCC) at a semi-rural academic medical center. METHODS: Retrospective, longitudinal study of the first 100 patients who underwent CEUS liver screening imaging over 2 years. Each patient underwent a standard of care abdominal ultrasound, which was checked with the radiologist, who searched for a focal lesion on the cine clips to target specifically with contrast. If none was present, the HCC contrast-enhanced screening protocol consisting of individual sweeps of the right and left lobes was performed from 0 to 60 s and 3-4 min post contrast-Lumason was utilized. Images, report details, and patient demographics were analyzed. RESULTS: 66 men and 34 women (average age, 59 ± 13 years) were included. On average, the distance from patient's home to our institution was 39 miles (range 2-179 miles). The majority of our patients were covered under Private insurance (46%) with 43% covered by Medicare. CEUS exams on average took 35 min to complete. Lumason was administered in split doses for an average total of 5 mL per exam. Of the 10 lesions identified, there were five LI-RADS 3, two LI-RADS 4, one LI-RADS 5, two LI-RADS M, and one bland portal vein thrombus. There were no complications reported. CONCLUSION: This semi-rural single-center study demonstrates the feasibility of starting a HCC CEUS screening program. CEUS can be performed in conjunction with routine ultrasound imaging with added benefit of identifying and characterizing lesions in one setting.

Eleven-Year Retrospective Report of Super-Selective Venous Sampling for the Evaluation of Recurrent or Persistent Hyperparathyroidism in 32 Patients.

PURPOSE: Parathyroid venous sampling (PAVS) is usually reserved for patients with persistent or recurrent hyperparathyroidism after parathyroidectomy with inconclusive noninvasive imaging studies. A retrospective study was performed to evaluate the diagnostic efficacy of super-selective PAVS (SSVS) in patients needing revision neck surgery with inconclusive imaging. MATERIALS AND METHODS: Patients undergoing PAVS between 2005 and 2016 due to persistent or recurrent hyperparathyroidism following surgery were reviewed. PAVS was performed in all patients using super-selective technique. Single-value measurements within central neck veins performed as part of super-selective PAVS were used to simulate selective venous sampling (SVS) and allow for comparison to data, which might be obtained in a non-super-selective approach. RESULTS: 32 patients (mean age 51 ± 15 years; 8 men and 24 women) met inclusion and exclusion criteria. The sensitivity and positive predictive value (PPV) of SSVS for localizing the source of elevated PTH to a limited area in the neck or chest was 96 and 84%, respectively. Simulated SVS, on the other hand, had a sensitivity of 28% and a PPV of 89% based on the predefined gold standard. SSVS had a significantly higher sensitivity compared to simulated SVS (p < 0.001). CONCLUSION: SSVS is highly effective in localizing the source of hyperparathyroidism in patients undergoing revision surgery for hyperparathyroidism in whom noninvasive imaging studies are inconclusive. SSVS data had also markedly higher sensitivity for localizing disease in these patients compared to simulated SVS.

Expandable Polyaryl-Ether-Ether-Ketone Spacers for Interbody Distraction in the Lumbar Spine.

Study Design Retrospective case series. Objective StaXx XD (Spine Wave, Inc., Shelton, CT, United States) is an expandable polyaryl-ether-ether-ketone (PEEK) wafer implant utilized in the treatment of lumbar degenerative disease. PEEK implants have been successfully used as interbody devices. Few studies have focused on expandable PEEK devices. The aim of the current study is to determine the radiographic and clinical outcome of expandable PEEK cages utilized for transforaminal lumbar interbody fusion in patients with lumbar degenerative diseases. Methods Forty-nine patients who underwent lumbar interbody fusion with implantation of expandable PEEK cages and posterior instrumentation were included. The clinical outcome was evaluated using the visual analog scale (VAS) and the Oswestry Disability Index (ODI). Radiographic parameters including disk height, foraminal height, listhesis, local disk angle of the index level/levels, regional lumbar lordosis, and graft subsidence were measured preoperatively, postoperatively, and at latest follow-up. Results At an average follow-up of 19.3 months, the minimum clinically important difference for the ODI and VAS back, buttock, and leg were achieved in 64, 52, 58, and 52% of the patients, respectively. There was statistically significant improvement in VAS back (6.42 versus 3.11, p < 0.001), VAS buttock (4.66 versus 1.97, p = 0.002), VAS leg (4.55 versus 1.96, p < 0.001), and ODI (21.7 versus 12.1, p < 0.001) scores. There was a significant increase in the average disk height (6.49 versus 8.18 mm, p = 0.037) and foraminal height (15.6 versus 18.53 mm, p = 0.0001), and a significant reduction in the listhesis (5.13 versus 3.15 mm, p = 0.005). The subsidence of 0.66 mm (7.4%) observed at the latest follow-up was not significant (p = 0.35). Conclusions Midterm results indicate that expandable PEEK spacers can effectively and durably restore disk and foraminal height and improve the outcome without significant subsidence.