Patient Outcomes and Cerebral Infarction after Ruptured Anterior Communicating Artery Aneurysm Treatment

BACKGROUND AND PURPOSE

Anterior communicating artery aneurysm rupture and treatment is associated with high rates of dependency, which are more severe after clipping compared with coiling. To determine whether ischemic injury might account for these differences, we characterized cerebral infarction burden, infarction patterns, and patient outcomes after surgical or endovascular treatment of ruptured anterior communicating artery aneurysms.

MATERIALS AND METHODS

We performed a retrospective cohort study of consecutive patients with ruptured anterior communicating artery aneurysms. Patient data and neuroimaging studies were reviewed. A propensity score for outcome measures was calculated to account for the nonrandom assignment to treatment. Primary outcome was the frequency of frontal lobe and striatum ischemic injury. Secondary outcomes were patient mortality and clinical outcome at discharge and at 3 months.

RESULTS

Coiled patients were older (median, 55 versus 50 years; P = .03), presented with a worse clinical status (60% with Hunt and Hess Score >2 versus 34% in clipped patients; P = .02), had a higher modified Fisher grade (P = .01), and were more likely to present with intraventricular hemorrhage (78% versus 56%; P = .03). Ischemic frontal lobe infarction (OR, 2.9; 95% CI, 1.1-8.4; P = .03) and recurrent artery of Heubner infarction (OR, 20.9; 95% CI, 3.5-403.7; P < .001) were more common in clipped patients. Clipped patients were more likely to be functionally dependent at discharge (OR, 3.2; P = .05) compared with coiled patients. Mortality and clinical outcome at 3 months were similar between coiled and clipped patients.

CONCLUSIONS

Frontal lobe and recurrent artery of Heubner infarctions are more common after surgical clipping of ruptured anterior communicating artery aneurysms, and are associated with poorer clinical outcomes at discharge.

The importance of assessing out-of-pocket payments when the financing of antiretroviral therapy is transitioned to domestic funding: findings from Vietnam

OBJECTIVE

To assess out-of-pocket payments and catastrophic health expenditures among antiretroviral therapy (ART) patients in Vietnam, and to model catastrophic payments under different copayment scenarios when the primary financing of ART changes to social health insurance.

METHODS

Cross-sectional facility-based survey of 843 patients at 42 health facilities representative of 87% of ART patients in 2015.

RESULTS

Because of donor and government funding, no payments were made for antiretroviral drugs. Other health expenditures were about $66 per person per year (95% CI: $30-$102), of which $15 ($7-$22) were directly for HIV-related health services, largely laboratory tests. These payments resulted in a 4.9% (95% CI: 3.1-6.8%) catastrophic payment rate and 2.5% (95% CI: 0.9-4.1%) catastrophic payment rate for HIV-related health services. About 32% of respondents reported, they were eligible for SHI without copayments. If patients had to pay 20% of costs of ART under social health insurance, the catastrophic payment rate would increase to 8% (95% CI: 5.5-10.0%), and if patients without health insurance had to pay the full costs of ART, the catastrophic payment rate among all patients would be 24% (95% CI: 21.1-27.4%).

CONCLUSIONS

Health and catastrophic expenditures were substantially lower than in previous studies, although different methods may explain some of the discrepancy. The 20% copayments required by social health insurance would present a financial burden to an additional 0.6% to 5.1% of ART patients. Ensuring access to health insurance for all ART patients will prevent an even higher level of financial hardship.

Retrospective analysis of antiretroviral therapy uptake and retention of male clients receiving methadone maintenance therapy in two provinces in Vietnam: potential synergy of the two therapies

BACKGROUND

Vietnam has a concentrated HIV epidemic with injection drug use being the dominant mode of HIV transmission. Vietnam has rapidly expanded antiretroviral therapy (ART) and methadone maintenance therapy (MMT). This study aims to analyze ART uptake and retention among male clients receiving MMT in Vietnam in the early phase of the MMT program.

METHODS

The male clients (age ≥18) who were newly enrolled in care or started ART at two HIV clinics in Hanoi (2009 to 2011) and three HIV clinics in Can Tho (2010 to 2012) were included for the analysis. The CD4 lymphocyte count at HIV care enrollment and ART initiation and retention on ART were retrospectively analyzed. The values of those receiving MMT were compared with the values of two groups: those in whom injection drug use (IDU) status was documented, but were not receiving MMT, and all male clients not receiving MMT. To analyze retention, survival analysis with log rank test and Cox proportional hazard model was used.

RESULTS

During the study period, 663 adult men were newly enrolled in HIV care (237 had IDU status documented) and 456 initiated ART (167 had IDU status documented). Among those who initiated ART, 28 were receiving MMT. At care enrolment, those receiving MMT had a median CD4 count of 230 (IQR 57-308) cells/mm3, while men self-reporting IDU and not receiving MMT and all men not receiving MMT had a median CD4 count of 158 (IQR 50-370) cells/mm3 and 143 (IQR 35-366) cells/mm3, respectively. At ART initiation, men receiving MMT had significantly higher CD4 count with median at 203 (IQR 64-290) cells/mm3 than men self-reporting IDU and not receiving MMT (80, IQR 40-220, cells/mm3, p = 0.038) and all men not receiving MMT (76, IQR 20-199, cells/mm3, p = 0.009). Those receiving MMT had a significantly higher retention rate than those self-reporting IDU but not receiving MMT (hazard ratio = 0.18, p = 0.019) and men not receiving MMT (hazard ratio = 0.20, p = 0.041).

CONCLUSIONS

Our analysis suggests that men receiving MMT in Vietnam are achieving relatively early uptake and high retention rates on ART. The findings support potential benefits of integrating MMT and ART services in Vietnam.

Estimating the Cost-Effectiveness of HIV Prevention Programmes in Vietnam, 2006-2010: A Modelling Study

Introduction

Vietnam has been largely reliant on international support in its HIV response. Over 2006-2010, a total of US$480 million was invested in its HIV programmes, more than 70% of which came from international sources. This study investigates the potential epidemiological impacts of these programmes and their cost-effectiveness.

Methods

We conducted a data synthesis of HIV programming, spending, epidemiological, and clinical outcomes. Counterfactual scenarios were defined based on assumed programme coverage and behaviours had the programmes not been implemented. An epidemiological model, calibrated to reflect the actual epidemiological trends, was used to estimate plausible ranges of programme impacts. The model was then used to estimate the costs per averted infection, death, and disability adjusted life-year (DALY).

Results

Based on observed prevalence reductions amongst most population groups, and plausible counterfactuals, modelling suggested that antiretroviral therapy (ART) and prevention programmes over 2006-2010 have averted an estimated 50,600 [95% uncertainty bound: 36,300–68,900] new infections and 42,600 [36,100–54,100] deaths, resulting in 401,600 [312,200–496,300] fewer DALYs across all population groups. HIV programmes in Vietnam have cost an estimated US$1,972 [1,447–2,747], US$2,344 [1,843–2,765], and US$248 [201–319] for each averted infection, death, and DALY, respectively.

Conclusions

Our evaluation suggests that HIV programmes in Vietnam have most likely had benefits that are cost-effective. ART and direct HIV prevention were the most cost-effective interventions in reducing HIV disease burden.

Intraoperative angiography for cranial dural arteriovenous fistula

BACKGROUND AND PURPOSE

IA is a valuable adjunct during surgery for a variety of neurovascular diseases; however, there are no reported series describing IA for DAVFs. This study was undertaken to evaluate the safety and efficacy of IA for DAVFs.

MATERIALS AND METHODS

A retrospective review of DAVF surgical cases during a 20-year period was conducted, and cases with IA were evaluated. Clinical details, surgical and angiographic findings, and postoperative outcomes were reviewed. The incidence of residual fistula on IAs, the utility of the surgical procedure, and the incidence of false-negative findings on IA were also determined.

RESULTS

IA was performed in 29 patients (31 DAVFs) for DAVFs. The distribution of the fistulas was the following: transverse-sigmoid (n = 9), tentorial (n = 6), torcular (n = 3), cavernous sinus (n = 4), SSS (n = 4), foramen magnum (n = 3), and temporal-middle fossa (n = 2). Twelve patients had undergone prior embolization, while 6 patients had unsuccessful embolization procedures. Thirty-eight surgeries were performed for DAVF in 29 patients, and IA was performed in 34 surgeries. Forty-four angiographic procedures were performed in the 34 surgeries. Nine patients underwent multiple angiographies. In 11 patients (37.9%), IA revealed residual fistula after the surgeon determined that no lesion remained. This led to further exploration at the same sitting in 10 patients, while in 1 patient, further surgery was performed at a later date. False-negative findings on IA occurred in 3 patients (10.7%).

CONCLUSIONS

IA is an important adjunct in surgery for DAVF. In this series, it resulted in further surgical treatment in 37.9% of patients. However, there was a 10% false-negative rate, which justified subsequent postoperative angiography.

CT angiography as a screening tool for dural arteriovenous fistula in patients with pulsatile tinnitus: feasibility and test characteristics

BACKGROUND AND PURPOSE

The diagnosis of intracranial DAVF with noninvasive cross-sectional imaging such as CTA is challenging. We sought to determine the sensitivity and specificity of CTA compared with cerebral angiography for DAVF in patients presenting with PT.

MATERIALS AND METHODS

Following approval of the institutional review board, we reviewed all patients who underwent CTA for PT from 2004 to 2009 and collected clinical and imaging data. Seven patients with PT and proved DAVF and 7 age- and sex-matched control patients with PT but no DAVF composed the study group. CTA images were blindly interpreted by 2 experienced neuroradiologists for the presence of 5 variables: asymmetric arterial feeding vessels, "shaggy" appearance of a dural venous sinus, transcalvarial venous channels, asymmetric venous collaterals, and abnormal size and number of cortical veins. Asymmetric attenuation of jugular veins was additionally assessed.

RESULTS

The presence of arterial feeders showed good test characteristics for screening, with a sensitivity of 86% (95% CI, 42-99) and a specificity of 100% (95% CI, 52-100). A shaggy sinus or tentorium was highly specific: sensitivity of 42% (95% CI, 11-79) and specificity of 100% (95% CI, 56-100). The presence of transcalvarial venous channels demonstrated a poor sensitivity of 29% (95% CI, 5-70) but a high specificity 86% (95% CI, 42-99). CT attenuation of the jugular veins showed statistically significant asymmetry in the DAVF group versus the control group (P < .05).

CONCLUSIONS

CTA can be used to screen for DAVF in patients with PT. The presence of asymmetrically visible and enlarged arterial feeding vessels has a high sensitivity and specificity for the diagnosis of DAVF.

Neurologic complications of arteriovenous malformation embolization using liquid embolic agents

BACKGROUND AND PURPOSE

Embolization of arteriovenous malformations (AVMs) is commonly used to achieve nidal volume reduction before microsurgical resection or stereotactic radiosurgery. The purpose of this study was to examine the overall neurologic complication rate in patients undergoing AVM embolization and analyze the factors that may determine increased risk.

MATERIALS AND METHODS

We performed a retrospective review of all patients with brain AVMs embolized at 1 center from 1995 through 2005. Demographics, including age, sex, presenting symptoms, and clinical condition, were recorded. Angiographic factors including maximal nidal size, presence of deep venous drainage, and involvement of eloquent cortex were also recorded. For each embolization session, the agent used, number of pedicles embolized, the percentage of nidal obliteration, and any complications were recorded. Complications were classified as the following: none, non-neurologic (mild), transient neurologic deficit, and permanent nondisabling and permanent disabling deficits. The permanent complications were also classified as ischemic or hemorrhagic. Modified Rankin Scale (mRS) scores were collected pre- and postembolization on all patients. Univariate regression analysis of factors associated with the development of any neurologic complication was performed.

RESULTS

Four hundred eighty-nine embolization procedures were performed in 192 patients. There were 6 Spetzler-Martin grade I (3.1%), 26 grade II (13.5%), 71 grade III (37.0%), 57 grade IV (29.7%), and 32 grade V (16.7%) AVMs. Permanent nondisabling complications occurred in 5 patients (2.6%) and permanent disabling complications or deaths occurred in 3 (1.6%). In addition, there were non-neurologic complications in 4 patients (2.1%) and transient neurologic deficits in 22 (11.5%). Five of the 8 permanent complications (2.6% overall) were ischemic, and 3 of 8 (1.6% overall) were hemorrhagic. Of the 178 patients who were mRS 0-2 pre-embolization, 4 (2.3%) were dependent or dead (mRS >2) at follow-up. Univariate analysis of risk factors for permanent neurologic deficits following embolization showed that basal ganglia location was weakly associated with a new postembolization neurologic deficit.

CONCLUSION

Embolization of brain AVMs can be performed with a high degree of technical success and a low rate of permanent neurologic complications.

Experimental study of intracranial hematoma detection with flat panel detector C-arm CT

BACKGROUND AND PURPOSE

Intracranial hemorrhage is a commonly acknowledged complication of interventional neuroradiology procedures, and the ability to image hemorrhage at the time of the procedure would be very beneficial. A new C-arm system with 3D functionality extends the capability of C-arm imaging to include soft-tissue applications by facilitating the detection of low-contrast objects. We evaluated its ability to detect small intracranial hematomas in a swine model.

MATERIALS AND METHODS

Intracranial hematomas were created in 7 swine by autologous blood injection of various hematocrits (19%-37%) and volumes (1.5-5 mL). Four animals received intravascular contrast before obtaining autologous blood (group 1), and 3 did not (group 2). We scanned each animal by using the C-arm CT system, acquiring more than 500 images during a 20-second rotation through more than 200 degrees . Multiplanar reformatted images with isotropic resolution were reconstructed on the workstation by using product truncation, scatter, beam-hardening, and ring-artifact correction algorithms. The brains were harvested and sliced for hematoma measurement and compared with imaging findings.

RESULTS

Five intracranial hematomas were created in group 1 animals, and all were visualized. Six were created in group 2, and 3 were visualized. One nonvisualized hematoma was not confirmed at necropsy. All the others in both groups were confirmed. In group 1 (with contrast), small hematomas were detectable even when the hematocrit was 19%-20%. In group 2 (without contrast) C-arm CT was able to detect small hematomas (<1.0 cm(2)) created with hematocrits of 29%-37%. The area of hematoma measured from the C-arm CT data was, on average, within 15% of the area measured from harvested brain.

CONCLUSIONS

The image quality obtained with this implementation of C-arm CT was sufficient to detect experimentally created small intracranial hematomas. This capability should provide earlier detection of hemorrhagic complications that may occur during neurointerventional procedures.

Endovascular embolization of the swine rete mirabile with Eudragit-E 100 polymer

BACKGROUND AND PURPOSE

Both adhesive and nonabrasive embolic agents are available for arteriovenous malformation (AVM) embolization. The purpose of this study was to evaluate a novel ethanol-based nonadhesive liquid embolic material in a swine AVM model.

MATERIALS AND METHODS

Eudragit (copolymer of methyl and butyl methacrylate and dimethylaminoethyl methacrylate) was dissolved in 50% ethanol and 50% iopamidol. Eudragit was injected into 9 retia mirabilia (RMs). Ethanol and iopamidol mixture were injected into 4 RMs for comparison. Three RMs embolized with Eudragit mixture were evaluated both angiographically and histopathologically acutely (3-24 hours) and at 30 days and 90 days after embolization.

RESULTS

No procedural complications from Eudragrit embolization were noted, including retention or adhesion of the microcatheter. Various degrees of inflammation were observed in the acute and 30-day specimens. Two RMs showed partial recanalization on both histopathology and follow-up angiography in the 30-day group. Arterial fibrosis and calcification were observed in the 30- and 90-day specimens. The internal elastic lamina was disrupted in the 30- and 90-day specimens, but there was no evidence of Eudragit extravasation or hemorrhage. Endothelial damage was seen in all specimens and was particularly severe in the 30- and 90-day specimens.

CONCLUSION

Eudragit polymer induced inflammation in thrombosis similar to n-butyl 2-cyanoacrylate, but without the disadvantages of perivascular hemorrhage and extravasation of embolization material. Although recanalization of some embolized RMs was noted, further investigation into Eudragit as a potentially useful embolic material for brain AVMs is warranted.

Treatment of traumatic cervical arteriovenous fistulas with N-butyl-2-cyanoacrylate

We report 2 cases of traumatic arteriovenous fistulas in the neck treated with transarterial embolization with n-butyl-2-cyanoacrylate (n-BCA). In both cases, covered stent placement across the fistula to preserve the artery was not possible. Detachable coil placement was attempted in one case but was not successful. Both fistulas were successfully treated with n-BCA embolization. To our knowledge, these are the first 2 such cases reported of high-flow cervical arteriovenous fistulas treated with n-BCA embolization.

A pilot of audio computer-assisted self-interview for youth reproductive health research in Vietnam

PURPOSE

Several recent adolescent health studies in Vietnam have shown low levels of premarital sex among youth compared to neighboring countries and other regions of the world. One possible explanation for these findings is that adolescents in Vietnam are less willing to reveal their true behaviors. This study aims to assess the level of reporting of sensitive behaviors/events using three methods of survey data collection: face-to-face interviewer-administered (IA), paper-and-pencil self-administered (SA) and AudioComputerAssisted Self Interview (ACASI).

METHODS

A randomized experiment was undertaken in Gialam, a suburb of Hanoi, among a sample of 2,394 youth ages 15 to 24 years. Respondents were randomly assigned to one of three interviewing methods, with females and males evaluated separately.

RESULTS

ACASI showed certain advantages with regard to respondent attitudes and perceptions of sensitive topics. ACAI also revealed higher prevalence rates for sensitive and stigmatized behaviors. Among those in the pencil and paper survey group it is estimated that 12.9% of unmarried males and 3.4% of unmarried females have had premarital sex. The rate found by using ACASI is higher at 17.1% in males (95% CI: 13.5-21.4) and 4.5% in females (95% CI: 2.7-7.3). Using ACASI, unmarried males also reported higher levels of risky sexual relations. For example, 7.8% confirmed visiting sex workers compared with only 1.2% in SA group and 3.9% in IA group. Additionally, ACASI respondents reported having had more sex partners by age group, gender and marital status.

CONCLUSIONS

When coupled with the emerging data from around the world, the present findings suggest that researchers should consider using ACASI for future studies dealing with sensitive and stigmatized topics.

Parent vessel occlusion for vertebrobasilar fusiform and dissecting aneurysms

BACKGROUND AND PURPOSE

Previous reports of outcome with permanent vessel occlusion (PVO) for large, giant, or fusiform aneurysms in the posterior circulation have been limited. We undertook this study to evaluate the perioperative (within 30 days) and follow-up outcomes for patients treated with permanent occlusion of the vertebral artery for vertebrobasilar fusiform and dissecting aneurysms.

METHODS

Thirteen consecutive patients were studied. Two groups were defined for the study. Group I patients underwent PVO to achieve complete thrombosis of the aneurysm. Group II patients underwent PVO to reduce flow to the aneurysm where complete thrombosis was not desirable. Modified Rankin scores were obtained at presentation and at follow-up (follow-up range, 1-76 months; mean, 22.0 months).

RESULTS

All group I aneurysms were shown to be thrombosed on the angiograms obtained at the immediate follow-up examinations. Improvement in outcome scores was achieved by all group I patients. Improvement in Rankin scores after endovascular treatment was statistically significant (P =.026). All group II patients had complete occlusion of the vertebral artery; however, continued filling of the fusiform aneurysm was still observed. Four patients in group II died during the follow-up period. Two of these deaths were attributable to the aneurysms. Of the remaining three patients, two experienced clinical worsening and one remained stable.

CONCLUSION

In this series, PVO for chronic fusiform and acute dissecting aneurysms of the vertebrobasilar system proved to be a useful therapeutic endovascular technique. Long-term outcomes suggest that patients with aneurysms involving only one vertebral artery, where complete thrombosis can be achieved, have better clinical outcomes than those who have aneurysms involving the basilar artery or both vertebral arteries, where complete thrombosis cannot achieved by using PVO.

Imaging of acute subarachnoid hemorrhage with a fluid-attenuated inversion recovery sequence in an animal model: comparison with non-contrast-enhanced CT

BACKGROUND AND PURPOSE

Fluid-attenuated inversion recovery (FLAIR) MR imaging sequences have been previously described in the evaluation of acute subarachnoid hemorrhage (SAH) in human subjects and have demonstrated good sensitivity. The purpose of this study was to evaluate a FLAIR sequence in an animal model of SAH and to compare the results with those obtained with non-contrast-enhanced CT.

METHODS

SAH was experimentally induced in 18 New Zealand rabbits by injecting autologous arterial blood into the subarachnoid space of the foramen magnum. Nine animals had high-volume (1-2 mL) injections, and nine animals had low-volume (0.2-0.5 mL) injections. Four control animals were injected with 0.5 mL of saline. The animals were imaged with a FLAIR sequence and standard CT 2-5 hours after injection. Gross pathologic evaluation of seven of the animals was performed. Four blinded readers independently evaluated the CT and FLAIR images for SAH and graded the probability of SAH on a scale of 1 to 5 (1 = no hemorrhage, 5 = definite hemorrhage).

RESULTS

Overall, the sensitivity of FLAIR was 89%, and the sensitivity of CT was 39% (P <.01). In animals with a high volume of SAH, the sensitivity of FLAIR was 100%, and the sensitivity of CT was 56%. In animals with a low volume of SAH, the sensitivity of FLAIR was 78%, and the sensitivity of CT was 22%. The specificity of FLAIR in animals without SAH was 100%, and the specificity of CT was 100%. The average reader score for FLAIR was 3.8, and that for CT was 2.2 (P <.001). Reader scores for FLAIR were higher than those for CT in 94% (P <.01) of animals with SAH and in 25% of animals without SAH (P >.05). Seven animals underwent gross pathologic examination, and all had blood in the subarachnoid space around the brain stem.

CONCLUSION

FLAIR was more sensitive than CT in the evaluation of acute SAH in this model, especially when a high volume of SAH was present. This study provides a model for further experimentation with MR imaging in the evaluation of SAH. These findings are consistent with those of current clinical literature, which show FLAIR to be an accurate MR sequence in the diagnosis of SAH.

Hyperperfusion syndrome with hemorrhage after angioplasty for middle cerebral artery stenosis

Hyperperfusion syndrome is a well-documented complication of carotid endarterectomy, as well as internal carotid artery angioplasty and stent placement. We report a similar complication after distal intracranial (middle cerebral artery [MCA] M2 segment) angioplasty. To our knowledge, this is the first report of hyperperfusion syndrome after intracranial angioplasty of a distal MCA branch.

Transforming growth factor beta-coated platinum coils for endovascular treatment of aneurysms: an animal study

OBJECTIVE

To test the hypothesis that coating platinum coils with transforming growth factor beta (TGFbeta) would improve the cellular proliferation within experimental aneurysms relative to uncoated coils.

MATERIALS AND METHODS

Elastase-induced saccular aneurysms were created in 12 New Zealand White rabbits. These aneurysms were embolized with platinum coils, either "control" (unmodified) coils or "test" (coated with TGFbeta) coils. Subjects were killed either 2 weeks (n = 3, control; n = 3, test) or 6 weeks (n = 3, control; n = 3, test) after embolization. Aneurysm tissue was embedded in plastic, sectioned, and stained with hematoxylin and eosin. The thickness of tissue covering the coils at the coil-lumen interface was measured by use of a digital microscope, and was compared between groups by use of the Student's t test (P < or = 0.05).

RESULTS

Two-week implantation samples demonstrated mean thickness of tissue overlying TGFbeta-coated coils of 36+/-15 microm and mean thickness of overlying control coils of 3+/-5 microm, indicating significantly thicker tissue growth covering test versus control coils (P = 0.02). Six-week implantation samples demonstrated mean thickness of tissue overlying TGFbeta-coated coils of 86+/-74 microm versus mean thickness overlying control coils of 37+/-6 mu; this difference did not reach statistical significance (P = 0.30). Thickness of tissue covering TGFbeta-coated coils did not change significantly from 2 to 6 weeks (P = 0.31). Tissue thickness over control coils increased significantly between 2 and 6 weeks (P = 0.002).

CONCLUSION

TGFbeta-coated platinum coils undergo earlier cellular coverage than standard platinum coils, but differences in coverage between coated and control coils are no longer present at later time points. These data suggest that improvements in intra-aneurysmal cellular proliferation resulting from coil modifications, although significant in the early postembolization phase, may dissipate over time.

Choroid plexus papilloma of the third ventricle: angiography, preoperative embolization, and histology

We report a unique case of choroid plexus papilloma of the third ventricle in an 8-month-old girl in which preoperative embolization played a salient role in management. Initial surgery was aborted due to excessive bleeding. Cerebral angiography demonstrated enlarged posterior choroidal arteries feeding the tumor, and intense, persistent tumor staining. These vessels were effectively embolized to stasis with polyvinyl alcohol particles. The patient underwent a second craniotomy and complete resection of the tumor with minimal blood loss. Postsurgical histology showed postembolization iatrogenic intratumoral necrosis.

Spinal cord infarction complicating embolisation of vertebral metastasis: a result of masking of a spinal artery by a high-flow lesion

SUMMARY

A 70-year-old woman presented with severe back pain secondary to metastasis of renal cell carcinoma to the second lumbar vertebral body. She had no evidence of spinal cord compression clinically or on MR imaging. Tumour embolisation was performed for pain relief The embolisation was complicated by spinal cord infarction resulting from angiographic masking of a spinal artery by diversion of contrast material into the high-flow tumour.

Endovascular treatment of experimental aneurysms by use of biologically modified embolic devices: coil-mediated intraaneurysmal delivery of fibroblast tissue allografts

BACKGROUND AND PURPOSE

Our long-term goal is to improve intraaneurysmal fibrosis after aneurysm embolization, by implanting exogenous fibroblasts, using platinum coils. For the current project, we tested two hypotheses: 1) that exogenous, fluorescence-labeled rabbit fibroblast allografts remained viable and proliferated within rabbit carotid arteries, and 2) that these fibroblast allografts could be reliably implanted into experimental aneurysms by use of platinum coils.

METHODS

Part 1. New Zealand White rabbit synovial fibroblasts obtained from a commercial vender were labeled with a fluorescent membrane marker. The common carotid arteries of New Zealand White rabbits were surgically exposed, ligated proximally and distally, and entered with 22-g angiocatheters. Through the angiocatheter we injected either phosphate-buffered saline-containing fluorescence-labeled fibroblasts (treatment vessels) or saline only (control vessels). The wounds were closed, and the subjects were kept alive for various time points up to 2 weeks. After sacrifice, the carotid artery segments were resected, processed for frozen-section histologic examination, and evaluated using epifluorescent microscopy and hematoxylin and eosin staining. Cell viability and proliferation were determined by comparing the treatment versus control vessels. Part 2. A) Fluorescence-labeled cells were grown in culture on platinum coils, which were then exposed to systemic arterial flow in the rabbit thoracic aorta for various lengths of time up to 40 minutes. The coil segments were then examined using fluorescent microscopy and the presence and relative amount of cells remaining on the coil were documented. B) Experimental aneurysms in rabbits were embolized with control platinum coils (n = 9) and platinum coils bearing rabbit synovial fibroblasts that were grown onto the coils in culture prior to implantation (n = 9). Subjects were sacrificed 3, 7, and 14 days after coil implantation. Histologic samples were studied to assess the presence or absence of nucleated cells within and around coil winds in order to determine whether fibroblasts had been successfully implanted into aneurysms. Data were evaluated using the chi-square test for statistical significance.

RESULTS

Part 1. Fluorescence-labeled cells were examined in the treatment carotid artery segments and results were recorded at all time intervals. The treatment vessel segments showed evidence of progressive cellular proliferation, leading to complete vessel fibrosis at 2 weeks. Conversely, control vessel segments were filled predominately with unorganized thrombus at each time interval. Part 2. A) Numerous labeled fibroblasts remained adherent to the coil despite prolonged exposure to systemic arterial flow. B) Fibroblasts were seen adjacent to or within the central lumen of coils in eight (88%) of nine aneurysms treated with cell-bearing coils. Nucleated cells were not present in any of the nine control coil subjects. This represented a statistically significant difference (P < .001).

CONCLUSION

Fibroblast allografts remain viable and proliferate in the vascular space in rabbits. Furthermore, these same fibroblasts, after seeding onto platinum coils in culture, remain protected within the lumen of the coils and are retained within the coil lumen even after prolonged exposure to arterial blood flow. Coils can be used to deliver viable fibroblasts directly into experimental aneurysms successfully. These findings indicate that coil-mediated cell implantation is feasible and may be a potential method of increasing the biological activity of embolic coils.

Magnetic resonance imaging in the evaluation of patients for percutaneous vertebroplasty

Osteoporosis and osteoporotic compression fractures of the vertebral bodies are major health problems facing women and older people of both sexes. In the last several years, percutaneous vertebroplasty has been developed as a treatment for pain caused by vertebral body compression fractures and primary or metastatic neoplasms. A large part of the success of this procedure depends on correct patient selection. As such, magnetic resonance imaging (MRI) plays a vital role in this process. In this review, the clinical evaluation of patients considered for vertebroplasty, the role of MRI in the pretreatment process, the postvertebroplasty appearance of the spine on MRI, and the future applications, such as real-time guidance with MR imaging, will be discussed.

Adjuvant use of epsilon-aminocaproic acid (Amicar) in the endovascular treatment of cranial arteriovenous fistulae

We report our experience with the use of the antifibrinolytic agent epsilon-aminocaproic acid (EACA), Amicar, as an adjuvant to endovascular treatment of cranial arteriovenous fistulae. We also review applications of antifibrinolytic agents to neurovascular disorders and discuss the mechanism of action, dosing strategy, contraindications, and possible complications associated with the use of EACA. We identified 13 patients with cranial arteriovenous fistulae (five direct carotid cavernous fistulae [CCF], seven dural arteriovenous fistulae [DAVF], and one vein of Galen malformation) who received EACA as an adjunct to endovascular treatment. In all cases embolic coils were the primary embolic agent. We reviewed the modes of initial endovascular therapy and angiographic findings immediately thereafter and the response to EACA. Two direct CCF and two DAVF were completely thrombosed on follow-up angiography, and two DAVF demonstrated diminished flow after EACA therapy. Seven fistulae did not respond to EACA. Four of eight tightly coiled fistulae thrombosed, while none of five loosely coiled fistulae thrombosed. None of four cases with a residual fistula separate from the coil mass underwent thrombosis with EACA, while four of nine cases without a separate fistula thrombosed. There was no morbidity related to EACA therapy. EACA may thus be useful as an adjunct to endovascular treatment of cranial arteriovenous fistulae. Loose or incomplete coil packing of the fistula predicts a poor response to EACA therapy.

1999 ARRS Executive Council Award. Creation of saccular aneurysms in the rabbit: a model suitable for testing endovascular devices. American Roentgen Ray Society

OBJECTIVE

This study developed an animal model of intracranial aneurysms suitable for evaluating emerging endovascular devices for aneurysmal therapy. We characterized the short-, medium-, and long-term attributes of this endovascular technique for saccular aneurysmal creation in the rabbit.

MATERIALS AND METHODS

The right common carotid artery was surgically exposed in nine New Zealand white rabbits. Using endovascular techniques, we occluded the origin of the right common carotid artery with a pliable balloon. Elastase was incubated endoluminally in the proximal common carotid artery above the balloon. The common carotid artery was ligated distally. Animals were studied angiographically and sacrificed at 2 weeks (n = 3), 10 weeks (n = 3), and 24 weeks (n = 3) after aneurysm creation. Histology was obtained.

RESULTS

Saccular aneurysms formed in eight of the nine rabbits. The aneurysm projected from the apex of an approximately 90 degree curve of the parent vessel, the brachiocephalic artery. Mean aneurysm diameter was 4.5 mm (SD, 1.2 mm), and mean height was 7.5 mm (SD, 1.6 mm). All samples showed thinned elastic lamina and no evidence of inflammation. In four of eight aneurysms, unorganized thrombus was present in the dome of the aneurysm.

CONCLUSION

Arterial aneurysms with intact endothelium and deficient elastic lamina were reliably created in an area of high shear stress in New Zealand white rabbits. Three of these aneurysms remained patent for at least 6 months. We found a simple procedure that can be readily applied to the testing of new endovascular devices for a reliable creation of aneurysms in rabbits.

Cerebral atrophy in Cushing's disease

BACKGROUND

Cushing's disease causes significant pathological changes throughout the body as a result of elevated cortisol levels. Very few systematic investigations have focused on the morphologic effects of hypercortisolism on the central nervous system. The validity of using premature cerebral atrophy as a diagnostic tool for Cushing's disease remains unknown.

METHODS

This study includes 63 patients with Cushing's disease who were evaluated and treated at the University of Virginia Medical Center. Radiologists randomly compared these individuals with age- and sex-matched controls in a blinded protocol, assessing the degree of cerebral atrophy on computed tomography and magnetic resonance scans.

RESULTS

Patients with Cushing's disease showed significant premature atrophy when compared with controls. This trend continued after subdividing the groups based on age and duration of symptoms except in the following groups: age greater than 60, duration of symptoms less than 1 year, and symptoms lasting between 4-5 years.

CONCLUSIONS

Excluding the three aforementioned groups, the hypercortisolemic state manifested in patients with Cushing's disease promotes the premature development of cerebral atrophy, which can be identified on routine radiologic imaging and may assist in the clinical diagnosis of the condition.

Histologic evaluation of platinum coil embolization in an aneurysm model in rabbits

PURPOSE

To characterize the histologic response to platinum coil embolization by using a rabbit aneurysm model.

MATERIALS AND METHODS

Saccular aneurysms were created in New Zealand White rabbits by using vessel ligation with intraluminal elastase incubation. Aneurysms were subsequently embolized by using platinum coils. Subjects were sacrificed at various intervals up to 12 weeks following coil embolization. The aneurysm cavities and adjacent vessels were embedded in methylmethacrylate, were sectioned, and were stained for histologic examination.

RESULTS

Two weeks following coil implantation, aneurysms were filled predominantly with unorganized thrombus. Six weeks following coil implantation, histologic features included complete filling of the aneurysm lumen with either prominent laminated but unorganized thrombus or areas of unorganized thrombus interspersed among areas of cellular infiltration. At 12 weeks following coil implantation, aneurysms were filled with the loosely packed, disordered cells contained within the extracellular matrix. Fibrosis or smooth muscle cell infiltration was not present in any of the 6- or 12-week samples.

CONCLUSION

Platinum coils placed into experimental saccular aneurysms in New Zealand White rabbits failed to elicit a fibrotic response. This model can be used for the testing of biologic modifications of platinum coils aimed at increasing intra-aneurysmal fibrosis.

Percutaneous vertebroplasty in vertebral osteonecrosis (Kümmell's spondylitis)

The authors report the clinical symptoms and response to therapy of a series of patients who presented with subacute or chronic back pain due to vertebral osteonecrosis (Kümmell's spondylitis) and who underwent percutaneous vertebroplasty.

The authors performed a retrospective chart review of a series of 95 patients in whom 149 painful, nonneoplastic compression fractures were demonstrated and who were treated with percutaneous transpediculate polymethylmethacrylate (PMMA) vertebroplasty. In six of these patients there was evidence of vertebral osteonecrosis, as evidenced by the presence of an intravertebral vacuum cleft on radiography or by intravertebral fluid on magnetic resonance (MR) imaging. Clinical and radiological findings on presentation were noted. Technical aspects of the vertebroplasty technique were compiled. Response to therapy, defined as qualitative change in pain severity and change in level of activity, was noted immediately following the procedure and at various periods on follow-up reviews.

One man and five women, who ranged in age from 72 to 90 years (mean 81 years), were treated. Each patient had one compression fracture. The fractures were at T-11 (one patient), L-1 (two patients), L-3 (two patients), and L-4 (one patient). The pain pattern was described as severe and localized to the affected vertebra, and sometimes radiated along either flank. Pain duration ranged from 2 to 12 weeks, and the pain was refractory to conservative therapy that consisted of bedrest, analgesics, and external bracing. At the time of treatment, all patients were bedridden because of severe back pain. In all patients either plain radiographic or computerized tomography evidence of intravertebral vacuum cleft or MR imaging evidence of vertebral fluid collection consistent with avascular necrosis of the vertebral body was demonstrated. Four patients underwent bilateral transpediculate vertebroplasty, and two patients underwent unilateral transpediculate vertebroplasty. The fracture cavities were specifically targeted for PMMA injection. Additional fortification of the osteoporotic vertebral body trabeculae was also performed when feasible. "Cavitygrams" or intraosseous venograms with gentle contrast injection were obtained prior to application of cement mixture. In all patients subjective improvement in pain and increased mobility were demonstrated posttreatment. The follow-up period ranged from 4 to 24 hours after treatment. Two patients made additional office visits at 1 and 3 months, respectively.

Patients presenting with vertebral osteonecrosis (Kümmell's spondylitis) often suffer from local paraspinous or referred pain. When performing vertebroplasty on these patients, confirmation of entry into the fracture cavities with contrast-enhanced "cavitygrams" should be performed prior to injection of PMMA cement. The response to vertebroplasty with regard to amelioration of pain and improved mobility is encouraging.

The fate of neuroradiologic abstracts presented at national meetings in 1993: rate of subsequent publication in peer-reviewed, indexed journals

BACKGROUND AND PURPOSE

Abstract presentations are a valuable means of rapidly conveying new information; however, abstracts that fail to eventually become published are of little use to the general medical community. Our goals were to determine the publication rate of neuroradiologic papers originally presented at national meetings in 1993 and to assess publication rate as a function of neuroradiologic subspecialty and study design.

METHODS

Proceedings from the 1993 ASNR and RSNA meetings were reviewed. A MEDLINE search encompassing 1993-1997 was performed cross-referencing lead author and at least one text word based on the abstract title. All ASNR and RSNA neuroradiologic abstracts were included. Study type, subspecialty classification, and sample size were tabulated. Publication rate, based on study design and neuroradiologic subspecialty, was compared with overall publication rate. Median duration from meeting presentation to publication was calculated, and the journals of publication were noted.

RESULTS

Thirty-seven percent of ASNR abstracts and 33% of RSNA neuroradiologic abstracts were published as articles in indexed medical journals. Publication rates among neuroradiologic subspecialty types were not significantly different. Prospective studies presented at the ASNR were published at a higher rate than were retrospective studies. There was no difference between the publication rate of experimental versus clinical studies. Neuroradiologic abstracts were published less frequently than were abstracts within other medical specialties. Median time between abstract presentation and publication was 15 months.

CONCLUSION

Approximately one third of neuroradiologic abstracts presented at national meetings in 1993 were published in indexed journals. This rate is lower than that of abstracts from medical specialties other than radiology.

Experimental side-wall aneurysms: a natural history study

We studied the natural history of canine side-wall experimental aneurysms to determine the incidence of spontaneous aneurysm thrombosis, to serve as control data for future studies focusing on development of aneurysm occlusion devices. Bilateral common carotid artery vein patch aneurysms were surgically created in eight mongrel dogs (20-25 kg). Duplex Doppler sonography was performed at 14 days and angiography between 30 and 210 days following aneurysm creation. Sonography demonstrated patency of 13 (81%) of 16 aneurysms. Patent aneurysms ranged in size from 8 x 10 mm to 14 x 16 mm. Conventional angiography was performed in four dogs approximately 30 days following aneurysm creation; in these four, all of 7 initially patent on sonography remained fully patent. One dog underwent conventional angiography at approximately 60 days following aneurysm creation; both aneurysms in this case remained widely patent. Three dogs underwent conventional angiography at approximately 200 days following aneurysm creation; all 4 aneurysms initially patent on sonography remained fully patent. None of the three aneurysms found to be occluded on sonographs demonstrated spontaneous recanalization. The canine side-wall aneurysm model is a valid tool for testing some aneurysm-occlusion devices, because control aneurysms remain patent indefinitely.

Perfusion imaging of the human lung using flow-sensitive alternating inversion recovery with an extra radiofrequency pulse (FAIRER)

Pulmonary perfusion is an important parameter in the evaluation of lung diseases such as pulmonary embolism. A noninvasive MR perfusion imaging technique of the lung is presented in which magnetically labeled blood water is used as an endogenous, freely diffusible tracer. The perfusion imaging technique is an arterial spin tagging method called Flow sensitive Alternating Inversion Recovery with an Extra Radiofrequency pulse (FAIRER). Seven healthy human volunteers were studied. High-resolution perfusion-weighted images with negligible artifacts were acquired within a single breathhold. Different patterns of signal enhancement were observed between the pulmonary vessels and parenchyma, which persists up to TI = 1400 ms. The T1s of blood and lung parenchyma were determined to be 1.46s and 1.35 s, respectively.

Posterior inferior cerebellar artery aneurysms associated with posterior fossa arteriovenous malformation: report of five cases and literature review

BACKGROUND

The association of posterior inferior cerebellar artery (PICA) aneurysms with posterior fossa arteriovenous malformation (AVM) is uncommon. Over the past 3 years, five patients with this condition were treated at this institution. A review of the clinical history of these and other reported cases has illuminated common threads in the presentation, treatment, and outcome of these lesions.

METHODS

The findings of 27 patients (5 from our institution and 22 from the medical literature) with PICA aneurysms associated with AVMs were reviewed.

RESULTS

Eighty-four percent of individuals presented with sub-arachnoid hemorrhage (SAH); 89% of these episodes resulted from aneurysm rupture documented by either intraoperative inspection or autopsy. All aneurysms were located on a feeding artery to the AVM, and 81% originated from distal portions of PICA. The majority of patients presented with Hunt & Hess grade I SAH; all patients who presented with hemorrhage were treated surgically. Surgical strategy was directed both to secure the aneurysm and to resect the AVM during the course of a single procedure. Although four individuals either died on admission or in the perioperative period, overall outcome was excellent or good in 82% of patients.

CONCLUSIONS

PICA aneurysms associated with AVMs most often involve the distal segments of the artery. Patients usually present with SAH secondary to aneurysmal rupture. Surgical clipping of the aneurysm and excision of the AVM is possible in a single procedure with minimal morbidity. Overall prognosis is favorable in 80% of the cases.

Dural arteriovenous fistula of the cervical spine presenting with subarachnoid hemorrhage

We describe a case of dural arteriovenous fistula (DAVF) presenting with subarachnoid hemorrhage (SAH). The diagnosis of DAVF was based on spinal angiography. A review of the literature revealed that five of 13 previously reported DAVFs of the cervical spine were accompanied by SAH. SAH has not been observed in DAVFs involving other segments of the spinal canal.

Complete duplication or extreme fenestration of the basilar artery

We describe a 42-year-old man with complete duplication or extreme fenestration of the basilar artery. We review the developmental anatomy and embryology and discuss the possible clinical implications and associated findings of this anomaly.

CT-guided percutaneous drainage of syringomyelia

PURPOSE

Our purpose is to describe CT-guided percutaneous drainage of syringomyelia as a possible contribution in patient management.

METHOD

CT-guided percutaneous drainage was performed on three patients with symptomatic syringomyelia. We determined the success of percutaneous decompression by subsequent CT and MRI. The effect of syringomyelia decompression in relation to the patient's symptoms was determined. This information was then used to help guide clinical management.

RESULTS

In Case 1, percutaneous drainage of a large syrinx in a C5 quadriplegic patient with increasing lower extremity spasticity demonstrated significant decompression by imaging but did not result in clinical improvement. A surgical procedure to decompress the syrinx was not performed on the basis of this information. In Case 2, percutaneous drainage of a large syrinx in a quadriplegic patient with increasing upper extremity numbness and weakness demonstrated significant decompression by imaging and resulted in sustained clinical improvement, temporarily obviating the need for surgery. In Case 3, percutaneous drainage of the rostral aspect of a septated syrinx cavity in a patient with a Chiari I malformation and a syringoperitoneal shunt in place resulted in decompression by imaging but failed to relieve the patient's newly developed symptoms. An additional shunt was therefore not placed. In no case did the patient experience periprocedural complications or worsening of symptoms.

CONCLUSION

CT-guided percutaneous drainage of syringomyelia is a safe and successful technique. It can be used diagnostically to identify patients that may or may not benefit from surgical syrinx decompression and in some cases may provide a temporary therapeutic alternative to surgery.

Brown-Séquard syndrome of the cervical spinal cord after chiropractic manipulation

We report a case of increased signal in the left hemicord at the C4 level on T2-weighted MR images after chiropractic manipulation, consistent with contusion. The patient displayed clinical features of Brown-Séquard syndrome, which stabilized with immobilization and steroids. Follow-up imaging showed decreased cord swelling with persistent increased signal. After physical therapy, the patient regained strength on the left side, with residual decreased sensation to pain involving the right arm.

Complications of peritoneal dialysis: evaluation with CT peritoneography

Computed tomographic (CT) peritoneography involves CT of the abdomen and pelvis after administration of a mixture of contrast material and dialysate. CT peritoneography can demonstrate a variety of complications of continuous ambulatory peritoneal dialysis. In patients with symptoms of peritonitis, CT peritoneography is better than conventional CT in demonstrating loculated fluid collections and indicates adhesions by means of uneven distribution of the contrast material-dialysate mixture. In patients with edema or abdominal bulging, CT peritoneography reliably shows the site of dialysate leakage and allows differentiation of a leak from a hernia. In patients with problems of fluid return, catheter malposition and its effect on dialysate distribution can be determined with CT peritoneography. In patients with poor ultrafiltration, demonstration of restricted space in the pelvis or poor distribution of fluid with CT peritoneography suggests adhesions. CT peritoneography also provides anatomic information for referring physicians that may determine whether treatment is medical or surgical.

Ion implantation and protein coating of detachable coils for endovascular treatment of cerebral aneurysms: concepts and preliminary results in swine models

OBJECTIVE

Complete anatomic obliteration remains difficult to achieve with endovascular treatment of wide-necked aneurysms using Guglielmi detachable platinum coils (GDCs). Ion implantation is a physicochemical surface modification process resulting from the impingement of a high-energy ion beam. Ion implantation and protein coating were used to alter the surface properties (thrombogenicity, endothelial cellular migration, and adhesion) of GDCs. These modified coils were compared with standard GDCs in the treatment of experimental swine aneurysms.

METHODS

In an initial study, straight platinum coils were used to compare the acute thrombogenicity of standard and modified coils. Modified coils were coated with albumin, fibronectin, or collagen and underwent Ne+ ion implantation at a dose of 1 x 10(15) ions/cm2 and an energy of 150 keV. Coils were placed in common iliac arteries of 17 swine for 1 hour, to evaluate their acute interactions with circulating blood. In a second study, GDCs were used to treat 34 aneurysms in an additional 17 swine. GDCs were coated with fibronectin, albumin, collagen, laminin, fibrinogen, or vitronectin and then implanted with ions as described above. Bilateral experimental swine aneurysms were embolized with standard GDCs on one side and with ion-implanted, protein-coated GDCs on the other side. The necks of aneurysms were evaluated macroscopically at autopsy, by using post-treatment Day 14 specimens. The dimensions of the orifice and the white fibrous membrane that covered the orifice were measured as the fibrous membrane to orifice proportion. Histopathological evaluation of the neck region was performed by light microscopy and scanning electron microscopy.

RESULTS

Fibronectin-coated, ion-implanted coils showed the greatest acute thrombogenicity (average thrombus weight for standard coils, 1.9 +/- 1.5 mg; weight for fibronectin-coated coils, 8.6 +/- 6.2 mg; P < 0.0001). By using scanning electron microscopy, an intensive blood cellular response was observed on ion-implanted coil surfaces, whereas this was rare with standard coils. At Day 14, greater fibrous coverage of the necks of aneurysms was observed in the ion-implanted coil group (mean fibrous membrane to orifice proportion of 69.8 +/- 6.2% for the ion-implanted coil group, compared with 46.8 +/- 15.9% for the standard coil group; P = 0.0143).

CONCLUSION

The results of this preliminary experimental study indicate that ion implantation combined with protein coating of GDCs improved cellular adhesion and proliferation. Future application of this technology may provide early wound healing at the necks of embolized, wide-necked, cerebral aneurysms.

Anterior cruciate ligament tear: indirect signs at MR imaging

PURPOSE

To establish the sensitivity and specificity of indirect signs at magnetic resonance (MR) imaging of anterior cruciate ligament (ACL) tear.

MATERIALS AND METHODS

MR images of the knees of 89 consecutive patients (54 with torn and 35 with normal ACLs) were reviewed.

RESULTS

The indirect signs were as follows (first percentage is sensitivity; the second, specificity): angle between lateral tibial plateau and ACL less than 45 degrees (90%, 97%); angle between Blumenstaat line and ACL more than 15 degrees (89%, 100%); bone contusions in lateral compartment (54%, 100%); position of posterior cruciate ligament (PCL) line (52%, 91%); PCL angle less than 107 degrees (52%, 94%); PCL bowing ratio more than 0.39 (34%, 100%); posterior displacement of lateral meniscus more than 3.5 mm (44%, 94%); anterior displacement of tibia more than 7 mm (41%, 91%); and lateral femoral sulcus deeper than 1.5 mm (19%, 100%).

CONCLUSION

Because the specificity is high, the presence of indirect signs corroborates the diagnosis of ACL tear. Because the sensitivity is low, the absence of these signs does not exclude the diagnosis of ACL tear.

Plantar plate of the foot: findings on conventional arthrography and MR imaging

The plantar plate of the foot is formed by the plantar aponeurosis and plantar capsule. The plantar plate arises from the distal plantar aspect of the metatarsal neck and inserts on the plantar aspect of the proximal phalangeal base. This thick plate supports the undersurface of the metatarsal head and resists hyperextension of the metatarsophalangeal joint (MTPJ) [1]. Plantar plate rupture may present as lesser metatarsalgia (the lesser metatarsals are the second through fifth), occasionally with exuberant synovitis. Plantar plate derangement also plays a central role in the genesis of the common hammertoe [2, 3]. Rupture or degeneration of the plantar plate destabilizes the MTPJ, allowing dorsal subluxation of the proximal phalanx. The resulting "cock-up" deformity at the MTPJ shortens and compromises the action of the extensor digitorum longus tendon, contributing over time to a flexion deformity at the interphalangeal joints.

CT appearance of splenic injuries managed nonoperatively

This essay illustrates the appearance of the traumatized spleen on CT scans obtained during the course of conservative treatment. Although the CT appearance of acute rupture of the spleen has been adequately described, little has been reported about the appearance of the spleen as it heals after trauma. Examples of CT studies of splenic injuries illustrate the various changes in appearance over time in the traumatized spleen that is treated nonoperatively.

Specific estrogen receptor binding and biological effects of 16 alpha-iodoestradiol on human breast cancer cells

16 alpha-Iodoestradiol was evaluated as an estrogen in MCF-7 and ZR-75-1 human breast cancer cells. 16 alpha-[125I]Iodoestradiol binds to equivalent numbers of specific estrogen receptors with a comparable binding affinity and similar sucrose density gradient behavior. 16 alpha-Iodoestradiol translocates receptor sites to the nucleus and induces a full range of estrogenic effects including thymidine incorporation, cell growth, and progesterone receptor. Because of its high specific activity, this compound may have unique applications on imaging of estrogen receptor-containing cells and specific receptor-mediated cytotoxicity.

The regulation of progesterone receptor by 17 beta estradiol and tamoxifen in the Zr-75-1 human breast cancer cell line in defined medium

The regulation of progesterone receptor by 17 beta estradiol and tamoxifen in the ZR-75-1 human breast cancer cell line in defined medium is described. ZR-75-1 cells maintained in serum free hormone supplemented medium minus estradiol lack progesterone receptor activity. Readdition of estradiol to these cells leads to a marked stimulation of progesterone receptor activity (0 to greater than 100 fmols of specifically bound progesterone per million cells). Tamoxifen (10(-6)M-10(-8)M) does not stimulate progesterone receptor activity in this cell line. The presence of progesterone receptor activity is not directly related to growth. Withdrawal of insulin in the continued presence of estradiol has no effect on progesterone receptor concentration although net cell growth ceases. Conversely, withdrawal of estradiol in the continued presence of insulin induces a cessation of net cell growth accompanied by a loss of all progesterone receptor activity within 3-5 days.

Association between steroid hormone receptor status and disease-free interval in breast cancer

The possibility of an association between steroid hormone receptor status and disease-free interval was examined in 292 patients with breast cancer. Estrogen receptor positivity was associated with a prolonged disease-free interval. This association was independent of age, menopausal status, tumor size, or nodal status. There was no association between the presence or absence of progesterone, androgen, or glucocorticoid receptor and disease-free interval.

Steroid hormone receptors in human colon cancers

Tumors from patients with primary colon cancer were studied for the presence of steroid hormone receptors for estrogen (E2), progesterone (Prog), dihydrotestosterone (DHT) and glucocorticoid. Ten of 33 (30%) tumors contained high affinity E2 receptors. Four were males and six females with positive assays predominantly from the left colon. Twenty-three of these tumors were also assayed for DHT and Prog and six (26%) contained all three receptors. An additional twelve tumors had at least one receptor, so that 70% of the tumors studied contained one or more receptors. Five of 22 (23%) samples were positive for glucocorticoid receptors. Common etiological factors associated with colon and breast cancer were briefly discussed. These factors, along with the presence of hormone receptors in primary colon malignancies suggest that some large bowel cancers may be endocrine-dependent.

Distribution, frequency, and quantitative analysis of estrogen, progesterone, androgen, and glucocorticoid receptors in human breast cancer

The distribution and frequency of steroid hormone receptors are described 329 patients with breast cancer. The distribution of each of the steroid hormone receptors is unimodal with a progressive increase in the proportion of patients positive at lower receptor values. Receptor values expressed as fmol/mg cytoplasmic protein are well correlated with values expressed as fmol/mg breast tumor. Estrogen receptor was positive in 53% of the patients; progesterone receptor was positive in 38% of the patients; glucocorticoid receptor was positive in 52% of the patients; and androgen receptor was positive in 31% of the patients. The type of tissue assayed did not affect steroid hormone receptor positivity. For primary tumors, there was no correlation between steroid hormone receptor positivity and location of the tumor in the breast, size of the tumor, or extent of the disease. Each of the steroid hormone receptors was positively associated with each of the other steroid hormone receptors. Estrogen receptor was correlated with menopausal status and axillary nodal status, but these correlations did not exist for the other steroid hormone receptors. Estrogen receptor was not correlated with age after adjustment for menopausal status. The other steroid hormone receptors were not correlated with age.

Steroid hormone receptors in human colon cancers

Tumors from patients with primary colon cancer were studied for the presence of steroid hormone receptors for estrogen (E2), progesterone (Prog), dihydrotestosterone (DHT) and glucocorticoid. Ten of 33 (30%) tumors contained high affinity E2 receptors. Four were males and six females with positive assays predominantly from the left colon. Twenty-three of these tumors were also assayed for DHT and Prog and six (26%) contained all three receptors. An additional twelve tumors had at least one receptor, so that 70% of the tumors studied contained one or more receptors. Five of 22 (23%) samples were positive for glucocorticoid receptors. Common etiological factors associated with colon and breast cancer were briefly discussed. These factors, along with the presence of hormone receptors in primary colon malignancies suggest that some large bowel cancers may be endocrine-dependent.

Association between steroid hormone receptors and response rate to cytotoxic chemotherapy in metastatic breast cancer

The influence of steroid hormone receptors on response rate to cytotoxic chemotherapy in 70 patients with metastatic breast cancer was determined in a retrospective study. We have previously reported that 34 of 45 patients with tumors containing low or absent estrogen-receptor values had objective responses to chemotherapy while three of 25 patients with positive estrogen-receptor tumors responded. In the present study, 22 of 34 patients with low or absent progesterone-receptor tumors had an objective response to cytotoxic chemotherapy, while none of eight patients with a positive progesterone-receptor tumor responded (P less than 0.05). Patients having tumors with a negative estrogen receptor and a negative progesterone receptor had a response rate of 88% (21 of 24 patients). There were three patients whose tumors were estrogen-receptor negative but progesterone-receptor positive; none had a response to chemotherapy. Chemotherapy response was not associated with the presence or absence of either androgen or glucocorticoid receptor. We conclude that progesterone-receptor values in addition to estrogen-receptor status may prove to be important correlates of response to cytotoxic chemotherapy in metastatic breast cancer. Androgen- and glucocorticoid-receptor analyses are not helpful in predicting response to chemotherapy.

The relation between estrogen receptors and response rate to cytotoxic chemotherapy in metastatic breast cancer

In a retrospective study we determined the relation between estrogen receptors and the response rate to cytotoxic chemotherapy in 70 patients with metastatic breast cancer. Thirty-four of 45 patients with low or absent estrogen-receptor values (less than 10 fmol per milligram of cytoplasmic protein) had objective responses to chemotherapy, whereas only three of 25 patients with higher values (greater than 10 fmol per milligram of cytoplasmic protein) responded (P less than 0.0001). There were no statistically significant differences between the two groups in age, menopausal status, disease-free interval, Karnofsky index or prior therapy. Differences in sites of involvement or type of chemotherapy did not account for the increased response rate in receptor-negative patients. We conclude that estrogen-receptor values are an important predictor of response to cytotoxic chemotherapy in metastatic breast cancer.