Clinical Experience with Foot and Ankle SPECT/CT:- From Dark horse to Fore runner of Foot and Ankle Imaging

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1 Clinical Experience with Foot and Ankle SPECT/CT:- From Dark horse to Fore runner of Foot and Ankle Imaging Poster No.: C-0113 Congress: ECR 2015 Type: Educational Exhibit Authors: K. E. Low 1, Z. Saad 2, S. J. Ong 2, J. Buscombe 2, B. Upadhyay 3 ; Westcliff on Sea/UK, Cambridge/UK, Basildon/UK Keywords: DOI: Trauma, Education, SPECT-CT, Extremities, Bones /ecr2015/C-0113 Any information contained in this pdf file is automatically generated from digital material submitted to EPOS by third parties in the form of scientific presentations. References to any names, marks, products, or services of third parties or hypertext links to thirdparty sites or information are provided solely as a convenience to you and do not in any way constitute or imply ECR's endorsement, sponsorship or recommendation of the third party, information, product or service. ECR is not responsible for the content of these pages and does not make any representations regarding the content or accuracy of material in this file. As per copyright regulations, any unauthorised use of the material or parts thereof as well as commercial reproduction or multiple distribution by any traditional or electronically based reproduction/publication method ist strictly prohibited. You agree to defend, indemnify, and hold ECR harmless from and against any and all claims, damages, costs, and expenses, including attorneys' fees, arising from or related to your use of these pages. Please note: Links to movies, ppt slideshows and any other multimedia files are not available in the pdf version of presentations. Page 1 of 14

2 Learning objectives 1. Describe the protocol for Tc-99m HDP SPECT-CT. 2. Case review of pathology identified on Tc-99m HDP SPECT-CT. 3. Follow-up of HDP SPECT-CT with subsequent MR and comparison of clinical utility of MR. 4. Review of clinical management of patient subsequent to SPECT-CT. Page 2 of 14

3 Background 1. Early use of Tc-99m bone scintigrams in the diagnosis of benign foot and ankle pathology suffers from poor anatomical and morphological detail. 2. The advent of SPECT-CT circumvents many of these problems although MR remains the workhorse of musculoskeletal imaging. 3. Tc-99m has some advantages over MR in that it is specific for bony pathology and there is better anatomical resolution, which allows for reconstruction. 4. Our institution acquires SPECT-CT capability in This is a case series detailing our clinical experiences. Page 3 of 14

4 Findings and procedure details Method: cases were reviewed retrospectively, over a period of 12 months. 2. The pathological diagnosis available on the PACS system was noted. 3. In addition, subsequent follow-up and management plan was reviewed via the clinic letters. 4. It was also noted whether subsequent MRI was performed and whether it added any extra information. Imaging Protocol 1. Single/dual phase imaging depending on indication. 2. Activity injected:- 750MBq to 4 hours post injection 4. Region of interest:- Distal tibia to sole of foot slice CT scanner, 1mm reconstruction x128 matrix Results and Findings:- 1. Range of pathology is depicted in Fig 1. Examples with description in the side bar. 2. Being a tertiary referral centre, follow-up data was only available for 22 of 41 patients. (Table 1) Of these SPECT-CT was useful in confirming or changing diagnosis in 21 of 22 patients. Of these, the majority (14, 64%) of them had conservative treatment ( physiotherapy, orthotics, pain management); 5,23% had surgical intervention; 2, 9% had ongoing clinical surveillance. Only in one case were the SPECT-CT not useful in the diagnosis and in this particular case, MR identified injury to the lateral collateral ligament which SPECT-CT did not, the patient had subsequent surgical intervention. Table 1.:- Influence of SPECT-CT on management in 22 cases Page 4 of 14

5 SPECT on Treatment Number % Management Useful Conservative Surgical 5 23 Ongoing 2 9 Not Useful We also evaluated if any MR was performed before or after the SPECT-CT detected pathology not seen on the SPECT-CT. None of the 4 MR studies performed before the SPECT-CT yielded additional information to the SPECT-CT and the SPECT-CT were used as problem solving tools. Of the 3 MR performed after SPECT-CT, 2 MR identified pathology( 1 plantar fasciitis and 1 lateral collateral ligament injury) and 1 MR was deemed unnecessarily performed after the SPECT-CT and did not yield any additional information ( 1 case of metatarsal fracture). In 33,80% of the cases, MR was not performed after SPECT-CT, 1 MR was cancelled after a positive SPECT-CT. Table 2:- MR done concurrently MR Time Value added N % Performed Not Performed Before SPECT/ CT After CT SPECT/ Add value 0 0 No added value 4 10 Add value 2 5 No added value Not done Cancelled Page 5 of 14

6 Images for this section: Fig. 1: Chart demonstrating the distribution of pathology in 41 Tc-99m SPECT-CT performed. Cambridge Fig. 2: Sesamoid fracture:- This is a 30 year old athlete with pain at the 1st MTPJ. SPECT-CT identifies a sesamoid fracture. The main utility of SPECT-CT is differentiating Page 6 of 14

7 this from bipartite sesamoid, which can occur in up to 30% of individuals, but would not demonstrate Tc-99m HDP uptake. Fig. 3: Sesamoiditis:- This is a 28 year old female runner. There is uptake in the hallucal sesamoid but no fracture and was diagnosed as sesamoiditis. Numerous pathologies which involves inflammation and swelling of the peritendinous structure of the sesamoid, including tendinitis, synovitis, chondromalacia, and sesamoid bursitis had been lumped together under the umbrella term of sesamoiditis. Page 7 of 14

8 Fig. 4: Os Trigonum:- 28 year old dancer, with posterior foot pain. There is intense uptake in the os trigonum, likely due to recurrent impaction of the posterior process of calcaneum against the posterior aspect of the talus. Fig. 5: Plantar fasciitis:- 40 year old, heel pain. This demonstrates calcaneal spur with intense uptake at its attachment to the plantar fascia Page 8 of 14

9 Fig. 6: Tarsal Coalitiion:- 50 year old patient with chronic medial ankle pain. There is intense uptake in the medial facet of the talus and the sustentaculum tali with a clear bony bridge seen between. Talocalcaneal coalition is a common form of tarsal coalition. Page 9 of 14

10 Fig. 7: Gout:- 29 year old Indian lady with right 1st MTP pain, thought to be osteoarthritis. CT demonstrates lytic lesion with a sclerotic lesion with intense uptake. She was subsequently found to have hyperuricemia. Fig. 8: Subtle tibial fracture:- Plain radiograph was unhelpful and in fact raised the suspicion of a fibular fracture. SPECT-CT not only highlighted the site of uptake, but demonstrate the fracture line. Page 10 of 14

11 Fig. 9: Navicular fracture:- Mid tarsal fractures are notoriously difficult on plain radiograph. CT clearly highlights site of fracture and demonstrate fracture line. Page 11 of 14

12 Fig. 10: Stress fracture of 2nd MT:- In this case, there is no fracture line, and in fact, the classical periosteal thickening is hardly perceptible in the plain radiograph. SPECT-CT demonstrates mid-shaft uptake in the 2nd MT typical of stress fracture. Page 12 of 14

13 Conclusion Whilst MR remain the main workhorse in foot and ankle imaging, SPECT-CT is rapidly gaining acceptance amongst orthopedic colleagues, and is seen at least as complementary to MR. Page 13 of 14

14 References REFERENCE 1. Lower extremity scintigraphy: the foot and ankle. Groshar D, Gorenberg M, Ben-Haim S, Jerusalmi J, Liberson A., Semin Nucl Med Jan;28(1): Detector multislice CT-skeletal scintigraphy image co-registration ( technical report).groves AM, Bird N, Tabor I, et al Nucl Med Commun , SPECT/CT in Imaging Foot and Ankle Pathology-The demise of other coregistration techniques, Mohan H, Gnanasegaran G., Vijayanathan S., Fogelman I., Seminars in Nuclear Medicine, Bone scintigraphy in the assessment of the hallucal sesamoids. Chisin R, Peyser A, Milgrom Foot Ankle Int.1995 May;16(5): Symptomatic and asymptomatic accessory navicular bones: findings of Tc-99m mdp bone scintigraphy. Chiu NT, Jou IM, Lee BF, et al. Clin Radiol. 2000;55:353Y Foot Fractures Frequently Misdiagnosed as Ankle Sprains Judd D., Kim D., Am Fam Physician Sep 1;66(5): The diagnostic value of single photon-emission computed tomography bone scans combined with CT, (SPECT-CT) in diseases of the foot and ankle, Singh V.K., Javed S., Parthipun A., Sott A. H. Foot and Ankle Surgery, vol. 19, no. 2, pp , Influence on Therapeutic Decision Making of SPECT-CT for Different Regions of the Foot and Ankle, Claassen L., Uden T., Ettinger M.,Daniilidis K., Stukenborg-Colsman, C. Plaass C.BioMed Research InternationalVolume 2014 (2014) Page 14 of 14