Cell refractive index for cell biology and disease diagnosis: past, present and future.

Cell refractive index is a key biophysical parameter, which has been extensively studied. It is correlated with other cell biophysical properties including mechanical, electrical and optical properties, and not only represents the intracellular mass and concentration of a cell, but also provides important insight for various biological models. Measurement techniques developed earlier only measure the effective refractive index of a cell or a cell suspension, providing only limited information on cell refractive index and hence hindering its in-depth analysis and correlation. Recently, the emergence of microfluidic, photonic and imaging technologies has enabled the manipulation of a single cell and the 3D refractive index of a single cell down to sub-micron resolution, providing powerful tools to study cells based on refractive index. In this review, we provide an overview of cell refractive index models and measurement techniques including microfluidic chip-based techniques for the last 50 years, present the applications and significance of cell refractive index in cell biology, hematology, and pathology, and discuss future research trends in the field, including 3D imaging methods, integration with microfluidics and potential applications in new and breakthrough research areas.

Angiographic evaluation of hepatic arterial injury after cisplatin and Gelfoam-based transcatheter arterial chemoembolization for hepatocellular carcinoma in a 205 patient cohort during a 6-year follow-up.

OBJECTIVE: To evaluate the overall and cumulative incidence, degree, interval change and predictors of hepatic arterial injury (HAI) after cisplatin and Gelfoam® (Upjohn, Kalamazoo, MI)-based transcatheter arterial chemoembolization (TACE) for hepatocellular carcinoma (HCC). METHODS: A total of 205 patients with HCC who underwent three or more sessions of TACE without additional surgical or local treatment were included. HAI was evaluated at each segment of the hepatic artery using a three-grade scale: 1 (slight wall irregularity), 2 (overt stenosis) and 3 (occlusion). HAI interval change was categorized into three groups: progression, stable state and improvement. Cumulative incidence of HAI was analysed using Kaplan- Meier method, and predictors of HAI (patient age, sex, portal vein thrombosis and Child-Pugh classification) were analysed by univariate logistic regression. RESULTS: HAI occurred in 50 of the 205 study patients (24.4%). The cumulative incidence of HAI was 16.0% [95% confidence interval (CI), 10.21-21.77] during 5 sessions of TACE, 52.1% (95% CI, 37.83-66.29) during 10 sessions and 68.0% (95% CI, 67.62-88.46) during 15 sessions. Initial HAI was interpreted as grades 1, 2 and 3 in 11 (22.0%), 17 (34.0%) and 22 (44.0%) patients, respectively. When the interval change was assessed in 48 patients with available follow-up TACE, 40 (83.3%) were included in the progression, 2 (4.2%) in the stable state and 6 (12.5%) in the improvement groups. The univariate analysis used to determine the predictors of HAI revealed no significant predictors. CONCLUSION: In three or more sessions of TACE, the incidence of HAI was 24%. Increasing TACE causes increased incidence of HAI. The initial presentation was most commonly grade 3, and 12.5% of the patients with HAI showed improvement of the HAI grade during follow-up TACE. ADVANCES IN KNOWLEDGE: In patients who underwent three or more sessions of cisplatin and Gelfoam-based TACE, the overall incidence of HAI was 24.4%, and increasing TACE causes increased incidence of HAI.

Incidence and management of postoperative abdominal bleeding after liver transplantation.

PURPOSE: To assess the incidence and management of postoperative abdominal bleeding after orthotopic liver transplantation (OLT) and to identify risk factors for abdominal bleeding. METHODS: We retrospectively reviewed the medical records of 1039 patients who underwent OLT at our institution from January 2008 to December 2010 seeking to identify subjects with posttransplantation abdominal bleeding, defined as any hemorrhage requiring radiologic intervention or laparotomy within the first month. RESULTS: Among the 1039 patients, 94 (9%) showed abdominal bleeding, occurring at a mean of 6.1 days (range, day 1 to 21 days). Active bleeding was controlled by endovascular interventional techniques (n = 37; 39%), by surgical ligation or vascular reconstruction (n = 43; 46%), or by sequential combinations of endovascular intervention and surgery (n = 14; 15%). The most frequent bleeding sites for radiologic intervention were the right inferior phrenic artery (n = 14), right and left epigastric arteries (n = 7), intercostal artery (n = 5) and right renal capsular artery (n = 4). The most frequent bleeding sites requiring laparotomy were the hepatic artery (n = 9), diaphragm (n = 8), inferior vena cava (n = 5), abdominal drain insertion site (n = 4), portal vein anastomosis site (n = 4), abdominal wall (n = 3), liver graft cut surface (n = 3), hilar plate (n = 3), and greater omentum (n = 3). Bleeding episodes were associated with greater patient age and increased intraoperative blood loss. CONCLUSIONS: The risk of bleeding from coagulopathy and iatrogenic injury is high during the early posttransplantation period. This risk of bleeding can be minimized by meticulous surgical dissection and bleeding control.

Persistent or recurrent varicocoele after failed varicocoelectomy: outcome in patients treated using percutaneous transcatheter embolization.

AIM: To determine the efficacy of percutaneous transcatheter embolization in the management of patients with spermatic varicocoeles persisting or recurring after surgery. MATERIALS AND METHODS: Over a period of 10 years, 28 patients (age range 13-55 years) were referred for percutaneous transcatheter embolization of postsurgical, recurrent varicocoeles. Medical documents were retrospectively reviewed to evaluate past surgical history, subjective symptoms, and results of scrotal examination, ultrasound, and semen parameters. Pre-embolization venograms were analysed to assess the anatomy of the testicular vein. The technical and clinical outcomes of embolization were then determined. RESULTS: The 28 patients included in the study had undergone laparoscopic varicocoelectomy (39.3%), high retroperitoneal ligation (25%), or inguinal ligation (25%). Subjective symptoms were scrotal pain (60.7%) and a palpable scrotal mass (50%) exclusively on the left side. Venograms revealed abnormalities of the left testicular vein in all cases. Embolization was technically successful in all but two cases, thus yielding an occlusion rate of 93%; a single case of suspected thrombophlebitis was the only complication. After excluding two, technically unsuccessful cases and one patient who was lost to follow-up, 25 patients underwent scrotal examination after embolization, which revealed complete resolution in 20 cases (80%), partial improvement in four cases (16%), and no improvement in a single case (4%). Among the follow-up group of patients, of the 12 who initially presented with scrotal pain, six (50%) were symptom-free and four (33.3%) had partial improvement. CONCLUSION: Percutaneous transcatheter embolization of the testicular vein is technically feasible and effective for managing postsurgical recurrent varicocoeles.

Effect of splenic artery embolization for splenic artery steal syndrome in liver transplant recipients: estimation at computed tomography based on changes in caliber of related arteries.

PURPOSE: To estimate the effect of splenic artery embolization (SAE) on blood flow in orthotopic liver transplantation (OLT) recipients with splenic artery steal syndrome (SASS) based on changes in caliber of related arteries upon serial computed tomography (CT) scans. METHODS: Between 2004 and 2007, nine OLT recipients with SASS underwent SAE. They had CT scans before and after SAE: short-, mid-, and long-term, ie, approximately 1 week, 1 month, and 1 year, respectively. The diameters of the celiac axis (CA), common hepatic artery (CHA), and splenic artery (SA) were measured with arterial phase of each CT scan and the ratios of SA to CHA diameter (SA/CHA) calculated to analyze their changes during the follow-up period. RESULTS: The diameters of celiac axis, CHA, and SA and SA/CHA changed most rapidly during the short-term period. The CHA diameter significantly increased short-term post-SAE by CT and slightly decreased thereafter. However, the mid-term and long-term post-SAE CT values were still significantly greater than those on the pre-SAE CT. The SA diameter steadily decreased throughout the follow-up. The SA/CHA decreased until the mid-term. The SA diameter and SA/CHA were significantly smaller upon mid-term and long-term post-SAE CT compared with those at pre-SAE CT. CONCLUSIONS: The effect of SAE to improve hepatic arterial flow in OLT recipients with SASS might be expected for at least approximately one year. The effect maximally occurred during the short-term after SAE on the basis of changes in the caliber of related arteries upon CT.

Volumetric analysis of the liver after right portal vein embolization: mid-term follow-up based on embolization score.

AIM: To evaluate liver volume alterations and liver function after right portal vein embolization (PVE) during mid-term follow-up based on embolization score. MATERIALS AND METHODS: Computed tomography (CT) images and liver function profiles were obtained before PVE, and at short-term (7-45 days), and mid-term follow-up (106-380 days) after PVE in all 30 patients. The patients were divided into group A (PVE score >or=3, n=20) and group B (PVE score <3, n=10). High score indicates more complete embolization. RESULTS: Left liver volume (LLV) and percentage future liver remnant (%FLR) increased significantly between pre-PVE and short-term follow-up and between short-term and mid-term follow-up in group A. Increase in FLR volume was significantly higher at the mid-term follow-up than at the short-term follow-up in group A. The ratio of embolized to total liver volume (RETLV) on short-term follow-up was significantly higher in group A than in group B. Aspartate transaminase (AST) and alanine transaminase (ALT) were elevated on short-term follow-up, whereas at mid-term follow-up in group A, they had significantly returned to the baselines. CONCLUSION: PVE resulted in continued compensatory hypertrophy of the unembolized liver during the 6-month follow-up. Compensatory hypertrophy in the unembolized liver was proportional to the ratio of embolization and to the embolized liver volume.

Primary hepatic angiosarcoma: imaging findings and palliative treatment with transcatheter arterial chemoembolization or embolization.

AIM: To describe the image findings and results of transcatheter arterial chemoembolization (TACE) or transcatheter arterial embolization (TAE) for treating primary hepatic angiosarcoma. MATERIALS AND METHODS: A retrospective review of the electronic medical database from 2002 to 2007, revealed six patients with primary hepatic angiosarcoma confirmed by percutaneous liver biopsy. The computed tomography (CT) and angiography imaging findings, the TACE or TAE results, and the post-procedure course were evaluated in all patients. RESULTS: On CT and angiography, each tumour appeared as a solitary mass or as multiple nodules or masses with heterogeneously early and progressive enhancement. One of the two patients with tumour response to TACE died 8 months after initial presentation, and the remaining patient was still alive at the last follow-up 12 months after initial presentation. However, two patients with no response to TACE and two patients who underwent emergent TAE for tumour rupture died 1 week to 5 months (mean 2.1 months) after initial presentation. CONCLUSIONS: Primary hepatic angiosarcoma appears as a solitary or multiple, hypervascular lesions with heterogeneously early and progressive enhancement on CT and angiography. Although TAE may be the primary procedure for achieving emergent bleeding control caused by the rupture of hepatic angiosarcomas, TACE may be effective for treating patients with a dominant hepatic angiosarcoma with or without intrahepatic metastases.

Transcatheter arterial chemoembolization vs. chemoinfusion for unresectable hepatocellular carcinoma in patients with major portal vein thrombosis.

BACKGROUND: Transcatheter arterial chemoembolization (TACE) has been limited in palliative treatment of unresectable hepatocellular carcinoma (HCC) with major portal vein (PV) invasion due to the possibility of liver failure following embolization. Transcatheter arterial chemoinfusion (TACI) has been an option in such cases. AIM: To compare clinical outcomes after TACE vs. TACI in HCC patients with major PV occlusion. METHODS: We compared clinical outcomes after TACE vs. TACI in HCC patients with major PV occlusion. From 2005 to 2007, 110 HCC patients with major PV thrombosis were treated with TACE (n = 49) or TACI (n = 61). RESULTS: The morbidity rate was similar for both TACE (6.1%) and TACI (6.5%) patients, and complications were adequately managed using medical treatment. The Kaplan-Meier survival analysis showed that the survival period was significantly longer for the TACE group (median: 14.9 months) than for the TACI (median: 4.4 months) group (P < 0.001). There was a higher probability of death in the TACI group than in the TACE group in both our multivariate Cox-proportional hazards (OR 3.09, P < 0.001) and the propensity score-matched (27 pairs) cohort analyses (OR 2.27, P = 0.024). CONCLUSIONS: Transcatheter arterial chemoembolization can be safely performed in HCC patients with main PV occlusion. Compared with TACI, TACE may result in longer survival of HCC patients with major PV occlusion.

Percutaneous transluminal angioplasty of suture-mediated closure device-related femoral artery stenosis or occlusive disease.

This study evaluates the efficacy of percutaneous transluminal balloon angioplasty (PTA) to treat stenosis or occlusion following haemostasis using a suture-mediated closure (SMC) device. Steno-occlusion occurred in 7 (0.4%) patients, some with claudication, others without. Steno-occlusion was diagnosed immediately after haemostasis in the four patients without claudication, but diagnosis was delayed in all three patients with claudication. Six of the patients subsequently underwent PTA using a contralateral femoral arterial approach. Technical success, clinical response and vessel patency were evaluated retrospectively. Follow-up angiography revealed focal segmental steno-occlusion (<1 cm) in the common femoral or proximal superficial femoral artery in four patients and long segmental occlusion (>1 cm) in the external iliac and common femoral arteries in three patients. PTA was technically successful in all patients (6/6, 100%). Among the three patients who developed delayed onset of claudication, one declined treatment and the claudication improved in two. Doppler ultrasound obtained 28-129 days (mean; 75 days) after PTA revealed patent arterial flow in six patients. One patient with delayed-onset occlusion refused the procedure because the symptoms were mild. This study has shown that PTA is a useful treatment for steno-occlusion following haemostasis using the SMC device. Careful angiography and review of the femoral bifurcation prior to use of an SMC device is important.

A case of successful embolotherapy for gastric ulcer bleeding from the intercostal artery after oesophagectomy and gastric reconstruction.

We report a successful treatment with coil embolisation of an intercostal artery for ulcer bleeding in a gastric tube in a 70-year-old man who underwent a total oesophagectomy and gastric tube reconstruction for oesophageal cancer. This case teaches us to search aberrant feeding vessels when active bleeding is suspected in reconstructed gastric tube in the patient with oesophagectomy and oesophagogastrostomy.

Adult-to-adult living donor liver transplantation at the Asan Medical Center, Korea.

Between February 1997 and December 2001, 311 adult-to-adult living donor liver transplants (A-A LDLTs) were performed at the Asan Medical Center for patients above 20 years of age. Indications for A-A LDLT were: chronic hepatitis B (203), chronic hepatitis C (5), hepatocellular carcinoma (64), alcoholic cirrhosis (9), cryptogenic cirrhosis (4), secondary biliary cirrhosis (5), primary biliary cirrhosis (1), Wilson' s disease (2), autoimmune hepatitis (1), hepatic tuberculosis (1), cholangiocarcinoma (1), fulminant hepatic failure (14) and primary non-function of cadaveric liver graft (1). Of 311 A-A LDLTs, 36 were of medical high urgency, 20 were for acute and subacute hepatic failure, 15 were for hepato-renal syndrome and 1 was for primary non-function. Recipient age ranged from 27 to 64 years. Donor age ranged from 16 to 62 years. There was no donor mortality. Implanted liver grafts were categorized into seven types: 175 modified right lobe (MRL), 70 left lobe, 32 right lobe, 20 dual grafts, 10 left lobe plus caudate lobe, three extended right lobe and one posterior segment. In MRL, the tributaries of the middle hepatic vein were reconstructed by interpositioning a vein graft. Indication for dual graft implantation was the same as single graft A-A LDLT, and four of 20 were emergency cases. Of 20 dual grafts, 14 received two left lobes, four received a left lobe and a lateral segment, one received a right lobe and a left lobe and one received a lateral segment and a posterior segment. Graft volume ranged from 28% to 83% of the standard liver volume of the recipients. There were 33 (10.6%) in-hospital mortalities (< 4 months) among the 310 patients after 311 A-A LDLTs. Of the 36 patients receiving emergency transplants, 31 survived. These encouraging results justify the expansion of A-A LDLT in coping with increasing demands, even in urgent situations. We have aimed to introduce the establishment of the efficacy of A-A LDLT in various end-stage chronic and acute liver diseases, as well as new technical advances to overcome small graft-size syndrome by using dual-graft implantation and MRL, both of which were first developed in our department.

Near real time in vivo fibre optic confocal microscopy: sub-cellular structure resolved.

We have built a fibre optic confocal reflectance microscope capable of imaging biological tissue in near real time. The measured lateral resolution is 3 micro m and axial resolution is 6 micro m. Images of epithelial cells, excised tissue biopsies, and the human lip in vivo have been obtained at 15 frames s-1. Both cell morphology and tissue architecture can be appreciated from images obtained with this microscope. This device has the potential to enable reflected light confocal imaging of internal organs for in situ detection of pathology.

Aortic dissection: percutaneous management with a separating stent-graft--preliminary results.

The authors used a separating stent-graft to treat Stanford type B aortic dissection. The separating stent-graft consists of two stents: a stent-graft and an inner bare stent. The separating stent-graft has three parts: a proximal stent, a graft made of synthetic polyester textile fiber, and a distal stent. A 12-F introducing sheath was used. After the separating stent-graft was placed, false-lumen thrombosis was evident in all six patients during a follow-up period of 206 days. The major advantages of this technique are that a cutdown and blood pressure control are not required.

Association between insulin-like growth factor-2 and metastases after transcatheter arterial chemoembolization in patients with hepatocellular carcinoma: a prospective study.

BACKGROUND: Hypoxia up-regulates insulin-like growth factor-2 (IGF-2) and thus stimulates the growth of hepatocellular carcinoma (HCC) cells. In the current study, the authors prospectively evaluated changes in plasma IGF-2 levels in HCC patients after transcatheter arterial chemoembolization (TACE), which usually results in hypoxic insult to liver tissue. The authors also examined the association between changes in plasma IGF-2 levels after TACE and HCC progression, especially in relation to metastasis. METHODS: Plasma IGF-2 levels were measured before and 4 weeks after TACE in 46 patients with HCC. Three months after TACE, the patients were evaluated for the occurrence of metastatic HCC. RESULTS: In 13 of the 46 patients, post-TACE plasma IGF-2 levels decreased by > 20% (Group 1) compared with their basal levels; in 18 patients, the IGF-2 levels changed within 20% (Group 2) and in 15 patients the IGF-2 levels increased by > 20% (Group 3). Plasma IGF-2 levels had a tendency to increase in patients with large-sized tumors, high serum alpha-fetoprotein (AFP) levels, and the heterogeneous uptake of iodized oil. Metastatic foci were found in 9 patients in Group 3 (60%), in contrast to only 3 patients in Group 2 (17%) and in none of the patients in Group 1 (P = 0.001). On multivariate analysis, higher Child-Pugh scores and increased plasma IGF-2 levels (Group 3) were found to be independent risk factors for metastasis. CONCLUSIONS: Increased plasma IGF-2 levels after TACE, which are common in patients with large-sized tumors and high serum AFP levels, appear to be associated with the occurrence of metastatic HCC after TACE.

Balloon dacryocystoplasty: results and factors influencing outcome in 350 patients.

PURPOSE: To evaluate the initial and long-term results of balloon dacryocystoplasty in the treatment of epiphora caused by obstruction of the lacrimal system with analysis of the procedure's favorable effects. MATERIALS AND METHODS: Four hundred thirty eyes of 350 patients with obstructions of the lacrimal system were enrolled. Dacryocystoplasty was performed with use of a balloon catheter and a ball-tipped guide wire. The lesions were categorized according to cause, severity, site of the obstruction, and diameter and inflation time of the balloon. The technical success, initial success (improvement of symptoms after 1 week), and long-term patency rates were calculated. These rates in each group were compared with the chi(2) test and the Kaplan-Meier method. RESULTS: The overall technical success rate was 95.3%. The overall initial success rate was 57.4%. There was no significant complication except for mild epistaxis in 12%. The 2-month, 1-year, and 5-year patency rates were 48.2%, 39.4%, and 36.9%, respectively. Initial success was influenced by the severity (P =.014) and the site (P <.001) of the obstruction, and the diameter of the balloon (P =.047). Long-term patency was affected by the site of the obstruction (P <.001) and the balloon inflation time (P <.001). Among the 183 initially ineffective and 88 recurrent cases, 62 underwent repeat balloon dacryocystoplasty, and the initial success rate was 38.7%. CONCLUSIONS: The initial success rate of balloon dacryocystoplasty is relatively low. However, long-term patency can be expected in cases with initial success. Some additional factors also should be considered for better results.

Ischemic bile duct injury as a serious complication after transarterial chemoembolization in patients with hepatocellular carcinoma.

BACKGROUND: Bile duct injuries after transarterial chemoembolization (TACE) have been reported; however, the exact pathogenic mechanisms and clinical implications of the injuries remain to be clarified. STUDY: A total of 950 consecutive patients with hepatocellular carcinoma (HCC) were studied. Among them, 807 were treated with TACE and the remaining 143 were treated with transarterial chemoinfusion (TACI) of cisplatin. RESULTS: None of 143 patients with HCC treated with TACI were found to have any radiographic evidence of biliary injury. In contrast, of the 807 patients treated with TACE, 17 (2%) developed biliary complications. Of all complications, 12 (71%) were subcapsular bilomas; 3 (17%), focal strictures of the common hepatic duct or common bile duct; and 2 (12%), diffuse mild dilatation of the intrahepatic bile ducts. Interestingly, 2 of the 12 bilomas were found in the lobe that was not embolized with gelatin sponge particles. The median numbers of TACE tended to be greater in the patients with focal stricture than in those with bilomas (6.0 vs. 2.5; p = 0.08). All 3 patients with focal strictures and 4 of the 12 patients with bilomas had associated serious bacterial infections at presentation. CONCLUSIONS: Bilomas seem to be caused by iodized oil rather than gelatin sponge particles; focal strictures of large bile ducts seem to be caused by gelatin sponge particles. We suggest that adjustments in the amounts of iodized oil or gelatin sponge particles and in the sites of embolization may reduce ischemic biliary injuries after TACE.

Fiber confocal reflectance microscope (FCRM) for in-vivo imaging.

In-vivo imaging can be achieved with a coherent-fiber-bundle based confocal reflectance microscope. Such a microscope could provide the means to detect pre-cancerous lesions in the cervix by characterizing cells' nuclear-to-cytoplasmic ratio. In this paper we present the design of such a fiber confocal reflectance microscope, with an emphasis on its optical sub-systems. The optical sub-systems consist of a commercially available microscope objective and custom designed telescope, scan lens, and coupling lens systems. The performance of the fiber confocal reflectance microscope was evaluated by imaging a resolution bar target and human cervical biopsy tissues. The results presented in this paper demonstrate a lateral resolution of 2 microm and axial resolution of 6 microm. The sensitivity of the system defined by the smallest refractive-index mismatch that can be detected is approximately Delta n 0.05.

Congenital lacrimal system obstruction: treatment with balloon dilation.

PURPOSE: To evaluate the safety and effectiveness of balloon dilation for the treatment of congenital lacrimal system obstruction. MATERIALS AND METHODS: Fluoroscopically guided balloon dilation was attempted in 20 eyes of 16 patients with an age range of 12-78 months (mean, 33 mo) for congenital lacrimal system obstruction. Fifteen eyes had complete obstruction at the valve of Hasner, three eyes had completely obstruction at the junction between the lacrimal sac and the nasolacrimal duct, and two eyes had partial obstruction at the nasolacrimal duct. Under general anesthesia, a ball-tipped guide wire was introduced through the superior punctum into the inferior meatus of the nasal cavity and pulled out through the naris with use of a hook. A deflated 3-mm-diameter balloon catheter was then advanced in a retrograde direction and the balloon was dilated. Every patient underwent an ophthalmic evaluation before the procedure and was scheduled to be followed with office examination at 1, 3, and 6 months after the procedure. RESULTS: There were no major complications. "Technical success" was defined as free passage of contrast medium through the entire lacrimal system to the nasal cavity. The procedure failed in one eye. After balloon dilation, all 19 eyes in which technical success was achieved showed improvement of epiphora. During the follow-up period of 2-33 months (mean, 16 mo), all eyes maintained improvement of epiphora and needed no further treatment. CONCLUSION: Balloon dilation is a safe and effective therapeutic technique for the treatment of congenital lacrimal system obstruction.

Use of a lacrimal stent retrieval hook in the removal of occluded plastic and expandable metallic lacrimal stents.

PURPOSE: To evaluate the clinical usefulness of a stent retrieval hook in the removal of occluded lacrimal stents. MATERIALS AND METHODS: The hook consisted of an inner hook part and an outer pusher part. Under administration of local anesthetic, the retrieval hook was introduced into the nasal cavity and aimed laterally toward the inferior meatus to grasp the distal end of the stent. After grasping the end of the stent, the sheath was pushed to fully grasp it. After that, the hook was pulled out of the external naris. The retrieval hook was used to remove 267 occluded lacrimal plastic or metallic stents. RESULTS: Technical success rate was 97% in the removal of plastic stents and 96% in the removal of metallic stents. The causes of technical failure were entrenchment of granulation tissue into the stent in six plastic stents and one metallic stent, and inaccessibility of the hook to the distal tip of the stent in one plastic stent. These eight stents were removed by an otorhinolaryngologist or an ophthalmologist. Epistaxis occurred in six patients, which was controlled by a nasal pack. CONCLUSIONS: The lacrimal stent retrieval hook seems useful for the removal of occluded stents.

Radiologic findings of abdominal polyarteritis nodosa.

OBJECTIVE: The purpose of this study was to evaluate the radiographic and imaging findings of seven patients with polyarteritis nodosa involving the abdomen. CONCLUSION: Vasculitis should be considered when multiple abdominal organs have abnormal radiologic findings; however, angiography is necessary to specifically diagnose polyarteritis nodosa.