Facial nerve injury: a complication of superficial temporal artery biopsy

Temporal artery biopsy in giant cell arteritis: clinical perspectives and histological patterns

Although its role has been debated, temporal artery biopsy (TAB) remains the gold standard for the diagnosis of cranial giant cell arteritis (GCA). The specificity of TAB is excellent and the sensitivity, albeit lower, is comparable with other diagnostic modalities used for the diagnosis of GCA. This outpatient procedure has a low rate of complications and is well integrated in the majority of healthcare systems. The length of the specimen, the number of the examined sections and the prolonged use of glucocorticoids before the biopsy may affect the outcome of the TAB as diagnostic tool. The typical histological findings in GCA are often characterized by granulomatous inflammation with infiltration of mononuclear cells with or without the presence of giant cell, varying degrees of external and internal elastic lamina damage and intimal thickening. Overlooking signs of inflammation in the adventitia and in connective tissue surrounding the temporal artery may lead to false negative results. The distinction between healed arteritis and age-related atherosclerosis may be challenging.

Ultrasound imaging of the dorsalis pedis artery as an early indicator of the precursory changes for rheumatoid vasculitis: A case series

Introduction

Clinical verification of rheumatoid vasculitis (RV) persists as a mid-to-late diagnosis with medical imaging or biopsy. Early and subclinical presentations of RV, in particular, can remain underdiagnosed in the absence of adequate diagnostic testing. In this study, the research demonstrated the precursory changes for RV in patients with rheumatoid arthritis (RA) using non-invasive ultrasound imaging of a peripheral vessel.

Method

Six participants were recruited: three participants with (RA) and three age- and gender-matched healthy controls. All participants completed a Foot Health Survey Questionnaire (FHSQ), and participants with RA completed a Rheumatoid Arthritis Disease Activity Index-5 (RADAI-5). Bilateral B-mode and Doppler ultrasound of the dorsalis pedis artery (DPA) was performed. The degree of inflammation, lumen and artery diameters, lumen diameter-to-artery diameter ratio and peak systolic velocity in the proximal DPA were compared between the two groups.

Results

The mean RADAI-5 score (5.4 ± 0.8 out of 10) indicated moderate disease activity amongst participants with RA. Inflammation was observed in the DPA wall in all participants with RA, compared to no inflammation observed in the control group (Friedmans two-way analysis: χ2 = 15.733, P = 0.003). Differences between groups for inflammation, lumen diameter and lumen diameter-to-artery diameter ratio were found (P < 0.034), without differences for artery diameter and peak systolic velocity (P > 0.605). DPA wall inflammation did not correlate with FHSQ scores (r = -0.770, P = 0.073).

Conclusion

Despite moderate RA disease activity, this is the first study to demonstrate the use of ultrasound to observe inflammation in small vessel disease. Our findings suggest ultrasound imaging may be a viable screening tool to demonstrate arterial wall inflammation, indicating the precursory changes of RV.

Biopsy of the Parietal Branch of the Superficial Temporal Artery for the Diagnosis of Giant Cell Arteritis

BACKGROUND

Biopsy of the superficial temporal artery (STA) is central to the diagnosis of giant cell arteritis (GCA), but determining the ideal biopsy site along the course of the STA continues to be a challenge. Traditionally, the frontal branch or preauricular region of the STA is biopsied because of their accessibility, but biopsy at these locations can produce visible cosmetic defects and social disruption that can be distressing to patients, as well as increase the likelihood of adverse events such as injury to the facial nerve. The authors describe a surgical technique of biopsy of the parietal branch of the STA to improve the patient's perioperative and postoperative experience.

METHODS

In this retrospective review, 24 patients with clinical suspicion of GCA who underwent biopsy of the parietal branch of the STA were identified. Patients underwent mapping of the branches of the STA with Doppler ultrasound before the procedure. Biopsy of the parietal branch of the STA was conducted using a CO 2 laser.

RESULTS

Twenty-four patients underwent biopsy of the parietal branch of the STA. Two patients were diagnosed on histopathology with GCA. All patients tolerated the procedure well and without complications.

CONCLUSION

Application of preoperative Doppler ultrasound mapping, use of a CO 2 laser for incisions and hemostasis, and selection of the parietal branch allowed for improved cosmetic outcomes, no associated adverse events, and improved overall patient experience. The authors advocate biopsy of the parietal branch of the superficial temporal artery for the diagnosis of GCA in the absence of contraindications.

Giant Cell Arteritis: State of the Art in Diagnosis, Monitoring, and Treatment

Giant cell arteritis (GCA) is the most prevalent subtype of vasculitis in adults. In recent years, there has been substantial improvement in the diagnosis and treatment of GCA, mainly attributed to the introduction of highly sensitive diagnostic tools, incorporation of modern imaging modalities for diagnosis and monitoring of large-vessel vasculitis, and introduction of highly effective novel biological therapies that have revolutionized the field of GCA. This article reviews state-of-the-art approaches for the diagnosis, monitoring, and treatment options of GCA.

Temporal artery biopsy: time for a rethink on training?

BACKGROUND

Temporal artery biopsy (TAB) is often performed by ophthalmology trainees without direct supervision. The traditional model of 'see one, do one, teach one' still prevails in most units. Whilst it is generally a safe procedure, damage to the temporal branch of the facial nerve has been reported when harvesting the frontal branch of the superficial temporal artery.

METHODS

A survey of trainees from Wessex, Wales, London and Severn deaneries was performed to look at current training techniques, anatomical knowledge and practice.

RESULTS

38 trainees responded to the survey, with complete responses from 28 participants. Formal teaching of the anatomical considerations in TAB was not reported by any trainee, with informal teaching being standard practice. Whilst 61% of respondents reported having learnt about the anatomical 'danger zone' for facial nerve damage, 97% of trainees chose an incision that fell within this zone when given a choice between potential incision sites.

CONCLUSION

TAB remains a largely trainee-taught, trainee-performed procedure. Most trainees are not aware of how to avoid the risk of damage to the temporal branch of the facial nerve. We suggest harvesting the parietal branch of the temporal artery via an incision outside the anatomical 'danger zone'. In our experience, this is an easily taught technique that minimises the potential risk of damage to the frontal branch of the facial nerve.

Temporal artery biopsy: A technical guide and review of its importance and indications

Temporal artery biopsy (TAB) is a surgical procedure that enables the histological diagnosis of giant cell arteritis (GCA). Performing a TAB requires expertise and a precise approach. Nevertheless, available data supports the value of tissue diagnosis in managing GCA. The current therapeutic recommendation for GCA is long-term glucocorticoid therapy, with an increasing emphasis on the addition of immunosuppressants/biotherapies. Though effective, immunosuppressants and other such biotherapies may put the patient at more risk. Optimizing the diagnosis through tissue evaluation is therefore important in weighing the risks and benefits of initiating therapeutic intervention. We evaluate the evidence supporting the importance of TAB and its indications. We also describe what technical approaches should be used to maximize sensitivity and to avoid possible complications during the procedure.

Giant cell arteritis with spontaneous remission

The case of a 75-year-old woman diagnosed with polymyalgia rheumatica (PMR), treated with low doses of prednisone, and with clinical and analytical remission is reported. Two years later, she presented with a clinical picture of giant cell arteritis (GCA), including headache, diplopia, jaw pain, feeling of swelling in both temples, and elevation of acute phase reactants. Symptoms spontaneously subsided 2 weeks later, while analytical parameters improved without any treatment. A high-resolution colour Doppler ultrasound showed thickening of the intima-media complex with 'halo' sign in the right temporal artery. A biopsy of the right temporal artery was performed, although it was not successful, as no artery could be found, and the procedure became more complicated with an eyebrow ptosis due to a lesion in the frontal branch of the facial nerve. GCA diagnosis was based on the clinical, laboratory, and ultrasound findings. The patient was treated with prednisone and methotrexate, without clinical or analytical relapse. Comments are presented on the described cases of GCA with spontaneous remission, and the most appropriate treatments in these cases are discussed. Other peculiarities of the case, such as the progression to GCA more than 2 years after the onset of PMR, and the complications from the temporal artery biopsy are also mentioned.

Safe Zone for Dissection in Frontotemporal Region to Avoid Injury to the Temporal Branch of Facial Nerve

ABSTRACT

The objective of this study is to provide a reliable roadmap for temporal branch of the facial nerve, in order to minimize, the risk of injury to the nerve during surgical dissections. A literature search was conducted on temporal branch of facial nerve. The date search range was 1950 to 2017. Databases searched included Medline, Web of science, Biosis, SciELO, Data Citation, and Zoologic Records. Data were collected on, author specialty, date of publication, and the relationship of the temporal branch of facial nerve to various landmarks in the frontotemporal region reported in human anatomic studies. Among the 48 studies reviewed, a total of 3477 anatomic dissections were performed in the craniofacial region. Temporal branch of facial nerve was located between 2.5 and 3 cm from lateral orbital rim. In relation to the zygomatic arch, it was found anywhere from the midpoint of the arch to 1 finger breath posterior to the arch. For the plane, it was most commonly described as being under the superficial temporal fascia (STF) or within the loose areolar tissue. Most anatomic dissections found 2 to 4 twigs of the temporal branch of facial nerve. In relation to the lateral canthus, it was found to be 2.85 +/- 0.69 cm superior and 2.54 +/- 0.43 cm lateral to the lateral canthus. Our study suggests consolidated data on surgical landmarks in order to ensure safe dissection in temporal region and prevent injury to the temporal branch of facial nerve.

Attitudes of Canadian Plastic Surgeons on Temporal Artery Biopsy in Giant Cell Arteritis Management

Temporal artery biopsies (TAB) rarely impact management of patients with suspected giant cell arteritis and carry complications. We sought plastic surgeons’ perspectives on this procedure’s risks and benefits.

Early variation of ultrasound halo sign with treatment and relation with clinical features in patients with giant cell arteritis

Objectives

To compare the ultrasound characteristics with clinical features, final diagnosis and outcome; and to evaluate the halo size following glucocorticoid treatment in patients with newly diagnosed GCA.

Methods

Patients with suspected GCA, recruited from an international cohort, had an ultrasound of temporal (TA) and axillary (AX) arteries performed within 7 days of commencing glucocorticoids. We compared differences in clinical features at disease presentation, after 2 weeks and after 6 months, according to the presence or absence of halo sign. We undertook a cross-sectional analysis of the differences in halo thickness using Pearson’s correlation coefficient (r) and Analysis of Variance (ANOVA).

Results

A total of 345 patients with 6 months follow-up data were included; 226 (65.5%) had a diagnosis of GCA. Jaw claudication and visual symptoms were more frequent in patients with halo sign (P =0.018 and P =0.003, respectively). Physical examination abnormalities were significantly associated with the presence of ipsilateral halo (P &lt;0.05). Stenosis or occlusion on ultrasound failed to contribute to the diagnosis of GCA. During 7 days of glucocorticoid treatment, there was a consistent reduction in halo size in the TA (maximum halo size per patient: r=−0.30, P =0.001; and all halos r=−0.23, P &lt;0.001), but not in the AX (P &gt;0.05). However, the presence of halo at baseline failed to predict future ischaemic events occurring during follow-up.

Conclusion

In newly diagnosed GCA, TA halo is associated with the presence of ischaemic features and its size decreases following glucocorticoid treatment, supporting its early use as a marker of disease activity, in addition to its diagnostic role.

Diagnosis of giant cell arteritis

GCA is the most common form of primary systemic vasculitis affecting older people. It is considered a clinical emergency because it can lead to irreversible blindness in around 20% of untreated cases. High doses of glucocorticoids should be initiated promptly to prevent disease-related complications; however, glucocorticoids therapy usually results in significant toxicity. Therefore, correct diagnosis is crucial. For many years, temporal artery biopsy has been considered the diagnostic ‘gold standard’ for GCA, but it has many limitations (including low sensitivity). US has proven to be effective for diagnosing GCA and can reliably replace temporal artery biopsy in particular clinical settings. In cases of suspected GCA with large-vessel involvement, other imaging modalities can be used for diagnosis (e.g. CT and PET). Here we review the current evidence for each diagnostic modality and propose an algorithm to diagnose cranial-GCA in a setting with rapid access to high quality US.

The role of vascular ultrasound in managing giant cell arteritis in ophthalmology

Giant cell arteritis is the most common systemic vasculitis in the elderly and is a potentially life-threatening ophthalmic emergency that can result in irreversible blindness. Blindness is most commonly associated with acute onset, irreversible arteritic ischemic optic neuropathy. Without treatment, second eye involvement may occur, resulting in bilateral blindness. Patients with established visual loss are treated with high-dose steroids and generally undergo a temporal artery biopsy to confirm their diagnosis. A significant number of patients are, however, referred for urgent ophthalmology assessment from concerns about "incipient" arteritic ischemic optic neuropathy. Before visual loss, patients may experience a range of ocular symptoms related to ischemia. This generally leads to treatment with high-dose systemic steroid and an urgent request for a temporal artery biopsy. Temporal artery biopsy is considered as the standard investigation for confirmatory diagnosis. It is generally arranged as soon as possible, although it is often not carried out for several days, and there may also be delays in histopathological reporting. It is often perceived that the patient is "safe" while on corticosteroids, in that they are being treated to avoid visual loss. What is not acknowledged, however, is that, if patients do not have giant cell arteritis and are being treated "just in case," they will often require a tapering of oral steroids over several weeks, exposing them to unnecessary and significant side effects. In the rheumatology setting, vascular ultrasound has emerged as a safe and reliable alternative to temporal artery biopsy as a point of care diagnostic tool in the management of giant cell arteritis. Given an experienced sonographer and optimal equipment, a rapid diagnosis can be established in a fast-track clinic setting, taking into consideration clinical assessment, scoring, and ultrasound findings. A huge advantage of ultrasound is that it provides immediate information that can be used to inform treatment decisions. We explore the evidence that supports the incorporation of vascular ultrasound into the ophthalmology repertoire to make a more efficient diagnosis that is cost-effective and associated with better patient outcomes, including a potential reduction in loss of sight and avoidance of unnecessary long-term steroid treatment by early exclusion of mimics.

Effects of incision location on specimen quality and complications for temporal artery biopsy

Objectives

Giant cell arteritis is a vision and potentially life-threatening condition requiring prompt and accurate diagnosis. The current gold standard of diagnosis is temporal artery biopsy. The purpose of this study is to review the technique of temporal biopsy in regard to incision placement, and to determine specimen quality and the incidence of complications, specifically seventh nerve injury.

Methods

Retrospective cohort study of 125 consecutive patients (137 biopsies) who underwent temporal artery biopsy. Variables concerning the procedure collected included laterality, incision placement, Doppler ultrasound utilization, length of intraoperative and pathologic specimens, result of the biopsy, motor nerve deficit, brow ptosis, and any intra or postoperative complications.

Results

The patient population was 73% female and 86% Caucasian. The average age at the time of the biopsy was 73.8 (range = 56–89, SD = 8.7). Doppler localization was used on 45% of patients. The mean intraoperative specimen length was 2.6 cm (range = 1.5–4.1, SD = 0.6) and fixed specimen length was 2.0 cm (range = 0.8–4.0, SD = 0.7). Biopsy results were positive in 18% of cases. There were no patients who displayed seventh nerve injury at one-week follow-up. One patient (0.7%) reported persistent anesthesia and one (0.7%) reported persistent paresthesia at the incision site. There were no other intraoperative or postoperative complications reported.

Conclusions

Placement of the incision at or posterior to the temporal hairline reduces the risk of seventh nerve injury. The posterior incision placement did not affect the quality of specimens or decrease the yield of biopsy results as compared to other studies. The overall complication rate (3%) was minimal and did not involve any motor nerve injury.

Radiographic study to assess the reliability of the Gillies approach for biopsy of the superficial temporal artery

Biopsy of the superficial temporal artery is often used in the diagnosis of giant cell arteritis, but at traditional sites there is a risk of injury to the facial nerve. Recently the Gillies incision has been suggested as an alternative means of access for the biopsy, but the anatomical basis of this has not been fully elucidated. We therefore undertook a radiographic review of 150 patients, and examining 300 vessels, to find out. Our results indicated that there is considerable variability in the position of the bifurcation of the superficial temporal artery, and so a Gillies approach may not be reliable, particularly if access to the bifurcation is required.

The Role of Ultrasound Compared to Biopsy of Temporal Arteries in the Diagnosis and Treatment of Giant Cell Arteritis (TABUL): a diagnostic accuracy and cost-effectiveness study

BACKGROUND

Giant cell arteritis (GCA) is a relatively common form of primary systemic vasculitis, which, if left untreated, can lead to permanent sight loss. We compared ultrasound as an alternative diagnostic test with temporal artery biopsy, which may be negative in 9-61% of true cases.

OBJECTIVE

To compare the clinical effectiveness and cost-effectiveness of ultrasound with biopsy in diagnosing patients with suspected GCA.

DESIGN

Prospective multicentre cohort study.

SETTING

Secondary care.

PARTICIPANTS

A total of 381 patients referred with newly suspected GCA.

MAIN OUTCOME MEASURES

Sensitivity, specificity and cost-effectiveness of ultrasound compared with biopsy or ultrasound combined with biopsy for diagnosing GCA and interobserver reliability in interpreting scan or biopsy findings.

RESULTS

We developed and implemented an ultrasound training programme for diagnosing suspected GCA. We recruited 430 patients with suspected GCA. We analysed 381 patients who underwent both ultrasound and biopsy within 10 days of starting treatment for suspected GCA and who attended a follow-up assessment (median age 71.1 years; 72% female). The sensitivity of biopsy was 39% [95% confidence interval (CI) 33% to 46%], which was significantly lower than previously reported and inferior to ultrasound (54%, 95% CI 48% to 60%); the specificity of biopsy (100%, 95% CI 97% to 100%) was superior to ultrasound (81%, 95% CI 73% to 88%). If we scanned all suspected patients and performed biopsies only on negative cases, sensitivity increased to 65% and specificity was maintained at 81%, reducing the need for biopsies by 43%. Strategies combining clinical judgement (clinician's assessment at 2 weeks) with the tests showed sensitivity and specificity of 91% and 81%, respectively, for biopsy and 93% and 77%, respectively, for ultrasound; cost-effectiveness (incremental net monetary benefit) was £485 per patient in favour of ultrasound with both cost savings and a small health gain. Inter-rater analysis revealed moderate agreement among sonographers (intraclass correlation coefficient 0.61, 95% CI 0.48 to 0.75), similar to pathologists (0.62, 95% CI 0.49 to 0.76).

LIMITATIONS

There is no independent gold standard diagnosis for GCA. The reference diagnosis used to determine accuracy was based on classification criteria for GCA that include clinical features at presentation and biopsy results.

CONCLUSION

We have demonstrated the feasibility of providing training in ultrasound for the diagnosis of GCA. Our results indicate better sensitivity but poorer specificity of ultrasound compared with biopsy and suggest some scope for reducing the role of biopsy. The moderate interobserver agreement for both ultrasound and biopsy indicates scope for improving assessment and reporting of test results and challenges the assumption that a positive biopsy always represents GCA.

FUTURE WORK

Further research should address the issue of an independent reference diagnosis, standards for interpreting and reporting test results and the evaluation of ultrasound training, and should also explore the acceptability of these new diagnostic strategies in GCA.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Gillies temporal incision: an alternate approach to superficial temporal artery biopsy

The main complications of a biopsy of the superficial temporal artery using a standard preauricular approach include scars on the face, weakness of the temporal branch of the facial nerve, and the possible harvest of a disease-free segment of artery. We describe a modification of the Gillies temporal approach, which when placed at the junction of the frontal and parietal branch can be easily modified to harvest either branch. It avoids scarring to the face as it is hidden within the hairline. The incision placed with specific measurements and palpation is easily reproducible. In patients with giant cell arteritis, arterial wall thickening, and narrowing of the lumen, reduced blood flow makes it harder to identify the artery with a Doppler scan. A procedure based on measurements and palpation is therefore likely to yield better results.

Giant cell arteritis

Giant cell arteritis (GCA) is the most common vasculitis of the elderly. The diagnosis can be challenging at times because of the limitation of the American Rheumatology Association (ARA) classification criteria and the significant proportion of biopsy-negative patients with GCA. We discuss the role of advanced imaging techniques, including positron emission tomography (PET) scanning, in establishing diagnosis and improved histopathology techniques to improve the sensitivity of temporal artery biopsy. There have been significant advances in the understanding of the pathogenesis of GCA, particularly the role of cytokine pathways such as the interleukins, IL-6-IL-17 axis, and the IL-12-interferon-γ axis and their implication for new therapies. We highlight that glucocorticoids remain the primary treatment for GCA, but recognize the risk of steroid-induced side effects. A number of pharmacotherapies to enable glucocorticoid dose reduction and prevent relapse have been studied. Early diagnosis and fast-track pathways have improved outcomes by encouraging adherence to evidence-based practice.

New developments in giant cell arteritis

Giant cell arteritis (GCA) is a medium-to-large vessel vasculitis with potentially sight- and life- threatening complications. Our understanding of the pathogenesis, diagnosis, and treatment of GCA has advanced rapidly in recent times. The validity of using the American College of Rheumatology guidelines for diagnosis of GCA in a clinical setting has been robustly challenged. Erythrocyte sedimentation rate, an important marker of inflammation, is lowered by the use of statins and nonsteroidal anti-inflammatory drugs. Conversely, it may be falsely elevated with a low hematocrit. Despite the emergence of new diagnostic modalities, temporal artery biopsy remains the gold standard. Evidence suggests that shorter biopsy lengths and biopsies done weeks to months after initiation of steroid therapy are still useful. New imaging techniques such as positron emission tomography have shown that vascular inflammation in GCA is more widespread than originally thought. GCA, Takayasu arteritis, and polymyalgia rheumatica are no longer thought to exist as distinct entities and are more likely parts of a spectrum of disease. A range of immunosuppressive drugs have been used in conjunction with corticosteroids to treat GCA. In particular, interleukin-6 inhibitors are showing promise as a therapy.

Safety and Effectiveness of a Small Incision Lateral Eyebrow Ptosis Repair Technique Using a Frontalis Muscle Transposition Flap

PURPOSE

To evaluate the safety and effectiveness of a frontalis muscle transposition flap for treatment of lateral eyebrow ptosis.

METHODS

The charts of all patients undergoing frontalis muscle transposition flap eyebrow ptosis repair from December 2013 to September 2014 were reviewed. Charts with inadequate photographs were excluded. Charts were reviewed for demographics, preoperative and postoperative photographs, surgical technique, and complications. The following parameters were assessed on preoperative and postoperative photographs: corneal diameter, central brow height, and lateral brow height. Measurements were normalized to a standard corneal diameter of 11.5 mm. Statistical analysis was performed in conjunction with the Cleveland Health Institute Biostatistics Department.

RESULTS

Forty-six total patients underwent frontalis muscle transposition flap eyebrow ptosis repair and the charts of 31 patients (53 cases) were reviewed. There were 20 female and 11 male patients. Average age was 69.1 ± 7.7 years (range: 50 - 86 years). There were 9 unilateral and 22 bilateral cases. Concomitant surgeries included upper blepharoplasty (33 cases), conjunctival-Mullerectomy blepharoptosis repair (3 cases), and intralesional tetracycline injection for festoons (3 cases). Average follow-up interval between surgery and the final postoperative photograph was 10.2 weeks (range: 6-26 weeks). Overall, lateral brow height increased postoperatively by 1.78 mm (p < 0.05). In patients that underwent frontalis muscle transposition flap alone, lateral brow height increased by 2.86 mm (p < 0.05). Scalp hypesthesia was documented in 10/31 patients, and resolved in 8/10 patients at last follow up.

CONCLUSIONS

A frontalis muscle transposition flap effectively addresses lateral eyebrow ptosis repair through a small, relatively concealed incision. It produces temporary scalp hypesthesia in a significant number of patients, and long-term results remain unknown.

Facial nerve injury during temporal artery biopsy

Temporal artery biopsy is considered the gold standard investigation of giant cell arteritis and is recommended in suspected cases despite a sensitivity of 81-91%. This review highlights the potential risk of facial nerve injury during temporal artery biopsy and introduces recent advances in the emerging role of imaging modalities. When these non-invasive techniques are used in conjunction with American College of Rheumatology scoring, which includes clinical features and biochemical test results, temporal artery biopsy may be avoided in selected cases.

Temporal artery biopsy size does not matter

This study aimed to clarify whether positive temporal artery biopsies had a greater sample length than negative biopsies in temporal arteritis. It has been suggested that biopsy length should be at least 1 cm to improve diagnostic accuracy. A retrospective review of 149 patients who had 151 temporal artery biopsies was conducted. Twenty biopsies were positive (13.3%), 124 negative (82.1%) and seven samples were insufficient (4.6%). There was no clinically significant difference in the mean biopsy size between positive (0.7 cm) and negative samples (0.65 cm) ( t-test: p = .43 NS). Ninety-four patients fulfilled all three ACR criteria prior to biopsy (62.3%) and four patients (2.6%) changed ACR score from 2 to 3 after biopsy. Treatment should not be delayed in anticipation of the biopsy or withheld in the case of a negative biopsy if the patient’s symptoms improve.

The use of temporal artery ultrasound in the diagnosis of giant cell arteritis in routine practice

AIM

The exact diagnostic role of temporal artery ultrasound (TAU) remains unclear. The aim of this study was to determine the sensitivity and specificity of a positive halo sign in patients undergoing TAU in a clinical setting, and to perform a review of existing evidence.

METHOD

Patients who had undergone TAU at a single centre in Australia were included in the study. The presence or absence of a halo sign and whether it was unilateral or bilateral was determined retrospectively from radiology reports. Pathology results were used to determine which patients underwent a temporal artery biopsy and if the biopsy was positive or negative. A case note review was performed to determine presenting clinical features and if a clinical diagnosis of giant cell arteritis was made. The sensitivity, specificity and likelihood ratios of TAU compared to both biopsy and clinical diagnosis were calculated.

RESULTS

Fifty patients were identified as having had a TAU (28% male, mean age 69). When compared to biopsy-proven cases, the sensitivity of a halo sign was 40%, specificity 81%, positive likelihood ratio 2.1 and negative likelihood ratio 0.7. When compared to clinical diagnosis, the sensitivity was 42%, specificity 94%, positive likelihood ratio 7.1 and negative likelihood 0.6.

CONCLUSIONS

Sensitivity and specificity results were comparable to the literature. A halo sign may preclude the need for biopsy in cases of high clinical suspicion and contraindications to surgery. Biopsy remains necessary in most cases, irrespective of whether a halo sign is present.