Effect of sympathetic block demonstrated by triple-phase bone scan

Quantitative evaluation of very acute stage of complex regional pain syndrome after stroke using three-phase bone scintigraphy

PURPOSE

Three-phase bone scintigraphy (TPBS) is an objective diagnostic test for complex regional pain syndrome (CRPS). The diagnostic importance of an increased uptake on the delayed phase has been proven in early CRPS, but that of the vascular and blood pool phases has not. The purpose of this study is to improve the diagnostic strength of the very acute stage of CRPS after stroke through a combined quantitative evaluation of each TPBS phase.

METHODS

Quantitative TPBS analysis was performed in 26 post-stroke hemiplegic patients with very acute stage of CRPS and in 12 controls with no CRPS after brain lesion. Regions of interest (hands without fingers--carpal bones, metacarpal bones and metacarpopharyngeal joints) were selected and the count ratios of the affected to unaffected sides were calculated.

RESULTS

The maximum values of control in each phase were used as the criteria of positive findings of each TPBS phase. Eleven patients in the vascular phase, 13 in the blood pool phase and 17 in the delayed phase had a higher assumption than the maximum values and a sensitivity of 42.3%, 50% and 65.4%, respectively. Twenty-one of 26 patients were interpreted as abnormal when at least one phase showed a positive finding. As a result, increased sensitivity of 80.8% and identical specificity of 100% were achieved.

CONCLUSION

These findings suggest that the combination of quantitative evaluation of each TPBS phase can improve the diagnostic strength of the very acute stage of CRPS after stroke.

Diagnosis of post-traumatic complex regional pain syndrome of the hand: current role of sympathetic skin response and three-phase bone scintigraphy

PURPOSE

To evaluate the role of sympathetic skin response (SSR) and three-phase bone scintigraphy (TPBS) in the diagnosis of complex regional pain syndrome (CRPS).

METHODS

60 patients with CRPS of the hand were recruited. TPBS was performed using a bolus injection of 20 mCi of Tc-99m methylene diphosphonate in an antecubital vein and blood flow (first phase) image, blood pool (second phase) image, and delayed (third phase) image obtained. Patients were considered to have CRPS when the blood pool and blood flow images showed diffuse asymmetric uptake, or when the delayed image indicated increased asymmetric periarticular uptake. SSR was measured simultaneously in the affected and unaffected hands. Standard surface electromyogram disc electrodes were applied to the palm and dorsum of both hands. Electrical stimuli were applied to the skin at the base of little and ring fingers of the unaffected hand. Patients were considered abnormal when response was absent or the peak-to-peak amplitude was <50% of the contralateral hand in at least 2 readings.

RESULTS

The delayed phase of TPBS tested positive in all; the first and second phases tested positive in 54 (90%) and 56 (93%) of the patients, respectively. Four of the 6 patients with a negative first phase had had symptoms persisting for more than 6 months, and the other 2 for about 3 to 6 months. No patient presenting within 3 months had a negative scan. SSR was absent in 16 (27%) patients and normal in 44 (73%). 11 (79%) of 14 patients who presented more than 6 months after symptom onset displayed an abnormal SSR, while only 10% of those presenting within 3 to 6 months and 11% of those presenting within 3 months had an abnormal SSR. 12 (75%) of the 16 patients with abnormal SSR had associated decreased sweating, compared with 2 (4.5%) of the 44 patients with a normal SSR.

CONCLUSION

TPBS is a very sensitive corroborative test to confirm the clinical suspicion of CRPS during the initial stages, but not in late cases. SSR can be used to document the sympathetic dysfunction in cases having an associated sweating abnormality and may have some diagnostic value in late cases of CRPS, when TPBS is less reliable.

Quantitative three-phase bone scintigraphy in the evaluation of intravenous regional blockade treatment in patients with stage-I reflex sympathetic dystrophy of upper extremity

OBJECTIVE

To investigate the role of quantitative three phase bone scintigraphy (QTPBS) in the evaluation of efficacy of intravenous regional blockade treatment in patients having reflex sympathetic dystrophy (RSD) of the upper extremity.

MATERIAL AND METHODS

Twenty-six patients with stage-I RSD were focused on in this study. Patients were treated with physical therapy and intravenous (I.V.) regional blockade therapy consisting of dexamethasone and lidocaine. All patients were clinically evaluated before and 1 month after the completion of the therapy protocol. QTPBS was applied to patients before therapy and 1 month after the therapy. As a control group, 11 healthy subjects also underwent QTPBS. Perfusion, hyperemic and fixation indices were calculated from three-phase bone scintigraphy.

RESULTS

All patients showed statistically significant clinical improvement after the therapy (p < 0.01). Pre-treatment, perfusion (1.67 +/- 0.63), hyperemic (1.44 +/- 0.48) and fixation (1.69 +/- 0.48) indices of patients were higher than those of healthy subjects (PI: 0.95 +/- 0.05, HI: 0.94 +/- 0.06, FI: 1.01 +/- 0.2) (p < 0.01) and all indices significantly decreased after the treatment (PI: 1.33 +/- 0.46, HI: 1.18 +/- 0.23, FI: 1.42 +/- 0.26) (p < 0.01).

CONCLUSION

I.V. regional blockade therapy combined with corticosteroids is a simple, safe and effective method for the treatment of patients with stage-I RSD in the upper extremity. QTPBS is a valuable and objective method to evaluate the response to therapy and may be useful for staging of patients and predicting the response to therapy.

"Growing pains" in children are not associated with changes in vascular perfusion patterns in painful regions

The most common cause of recurring childhood musculoskeletal pain is termed "growing pains" (GP). The etiology and pathogenesis are unknown. There is an increased prevalence of migraine headaches in families with children with GP. This fact, and the sudden onset and severity of GP episodes, has led to speculation that GP may have a vascular component. Therefore, we investigated whether GP are associated with vascular perfusion changes, measured by technetium-99 methylene diphosphate (MDP) bone scintigraphy. Eleven patients with GP who underwent technetium-99 MDP bone scans were compared to 12 children who underwent bone scans for other indications. The uptake in the blood pool phase, static images, and blood pool phase/static image ratio were measured in the right mid-tibia region (painful among patients with GP) and right mid-femur (non-painful). Student's t-test was used to compare these measurements at painful and painless regions among GP children, and to compare children with or without GP. There were no significant differences between children with GP and without GP in the blood pool, static images, and blood pool/static images in all localities. There were also no significant differences among patients with GP between painful regions and non-painful regions. We conclude that GP are not associated with vascular perfusion changes in painful regions as opposed to migraine headaches.

Complex regional pain syndrome (CRPS) with resistance to local anesthetic block: a case report

We present a case of complex regional pain syndrome (CRPS) Type 1 in a 12-year-old girl. The patient did not respond to the usual therapeutic modalities used to treat CRPS, including physical therapy, lumbar sympathetic block, epidural local anesthetic block, intravenous lidocaine infusion, or other oral medications. Of note is the fact that, during epidural block, the patient demonstrated a resistance to local anesthetic neural blockade in the area of the body involved with the pain problem. The mechanism of this resistance could be related to the changes in the dorsal horn cells of the spinal cord, secondary to activation of N-methyl-D-aspartate receptors, which may play a role in the pathophysiology of this pain syndrome.

Autonomic regulation of lymphatic flow in the lower extremity demonstrated on lymphoscintigraphy in patients with reflex sympathetic dystrophy

PURPOSE

Nuclear medicine techniques were used to show that the peripheral lymphatics are under autonomic control in much the same way as the blood vessels that supply the same anatomic region.

METHODS

Three patients with complex regional pain syndrome type 1 (reflex sympathetic dystrophy) involving a lower extremity were evaluated using three-phase bone scintigraphy and peripheral lymphoscintigraphy. Each patient was treated with ipsilateral chemical lumbar sympathectomy, and lymphoscintigraphy was repeated within several days of the procedure.

RESULTS

All three patients had evidence of decreased flow (compared with the contralateral extremity) to normal flow after ipsilateral sympathectomy. Bone scintigraphy, before and after sympathectomy, was difficult to interpret because of the effects of altered weight bearing. Two patients who had unilateral peripheral edema showed marked improvement after sympathectomy and increased lymphatic flow.

CONCLUSIONS

Peripheral lymphatic function is controlled by the autonomic nervous system. In reflex sympathetic dystrophy, peripheral edema may be caused by an increased sympathetic stimulus to the lymphatics. Further study of this phenomenon may show that nuclear medicine studies, such as bone scintigraphy and lymphoscintigraphy, can be used to distinguish patients who will benefit from sympathectomy from those who will not, thereby obviating invasive testing and unnecessary invasive treatment.

Reflex sympathetic dystrophy of the lower extremity in tetraplegia: case report

Reflex sympathetic dystrophy (RSD) of the upper extremities has been reported to occur following complete and incomplete injuries of the cervical cord. Such reports describe the value of the three-phase radionuclide bone scan (TPBS) in differentiating RSD from pain of other sources. To our knowledge, RSD of the lower extremities has not been reported in a patient with tetraplegia. We report a case of lower extremity RSD in a patient with complete traumatic injury of the cervical cord. The case illustrates the use of the TPBS to differentiate RSD from heterotopic ossification (HO) in the lower extremities. THe successful use of the alpha-adrenergic blocker, phenoxybenzamine, in the treatment of RSD is described. Follow-up to 30 months has shown no evidence of recurrence, and complete resolution of the scintigraphic findings.

"Cold" reflex sympathetic dystrophy in an adult

The classical presentation of acute reflex sympathetic dystrophy (RSD) or triple-phase bone scintigraphy usually consists of increased periarticular uptake in each phase. The authors present a rare case of acute adult RSD characterized by bone hypofixation of Tc-99m MDP. Reflex sympathetic dystrophy in adults and children is reviewed.

The role of bone scintigraphy in diagnosing reflex sympathetic dystrophy

Three-phase bone scintigraphy is used often to diagnose reflex sympathetic dystrophy of the hand. This study presents an analysis of the literature relating three-phase bone scanning to reflex sympathetic dystrophy in the upper extremity. The data show a wide variability in scintigraphic accuracy in patients with clinically obvious reflex sympathetic dystrophy. The results of bone scintigraphy correlate best with the clinical diagnosis of reflex sympathetic dystrophy within the first 20-26 weeks of onset. Even then, the sensitivity in the most recent series approximates 50%. After 26 weeks, there is a poor correlation between three-phase bone scanning and reflex sympathetic dystrophy. Consequently, three-phase bone scintigraphy should not be used as a major criterion in diagnosing reflex sympathetic dystrophy. The diagnosis of reflex sympathetic dystrophy remains a clinical diagnosis made by an experienced hand surgeon.