Diagnostic performance of MDCT, PET/CT and gadoxetic acid (Primovist(®))-enhanced MRI in patients with colorectal liver metastases being considered for hepatic resection: initial experience in a single centre.

PURPOSE: To compare the relative diagnostic performance of MDCT, PET/CT and Primovist-enhanced MRI (P-MRI) in the pre-resection work-up of colorectal cancer (CRC) liver metastases. METHOD AND MATERIALS: This was a retrospective study of consecutive referrals for CRC liver metastases. All patients had MDCT, PET/CT and P-MRI examinations within 3 months of each other. They were divided into 2 groups: resected and unresected. Patients in the resected group underwent liver resection within 3 months of the imaging studies. In the unresected group, patients were unresectable by imaging criteria or are awaiting surgery. Standard of reference (SOR) was intra-operative ultrasound findings and pathology for the resected group. Intermodality comparison was the SOR for the unresected group. Number of lesions identified by each imaging modality for each patient was recorded. Sensitivity (95% CI) and PPV were calculated for each imaging modality in the resected group. RESULTS: There were 19 patients in the resected group and 11 patients in the unresected group. The sensitivity (96%) and PPV (0.91) of P-MRI were both superior to that of MDCT (P = 0.0009) and PET/CT (P = 0.0003). Intermodality comparison showed that P-MRI detected more lesions than MDCT and PET/CT. CONCLUSION: The sensitivity and PPV of P-MRI was superior to that of MDCT and PET/CT. P-MRI probably has the most added value if used after MDCT and PET/CT in patients still considered eligible for liver resection.

Hepatocellular carcinoma complicating cystic fibrosis related liver disease.

Early diagnosis and treatment of the respiratory and gastrointestinal complications of cystic fibrosis (CF) have led to improved survival with many patients living beyond the fourth decade. Along with this increased life expectancy is the risk of further disease associated with the chronic manifestations of their condition. We report a patient with documented CF related liver disease for which he was under routine surveillance that presented with histologically proven hepatocellular carcinoma (HCC). It is important that physicians are aware of this association as increased vigilance may lead to earlier diagnosis and perhaps, a better outcome.

A clinical test to avoid sural nerve injuries in percutaneous Achilles tendon repairs.

Percutaneous repairs of Achilles tendon ruptures has gained popularity due the reduced incidence of wound complications, however its use is still limited by the high incidence of sural nerve injuries associated with these repairs. The only technique described to avoid this adverse event is to surgically expose the nerve peri-operatively. In our study, we describe and validate a clinical technique to identify the sural nerve. The sural nerve was mapped using this technique both clinically and by Ultrasound (US) in a cohort of male subjects with intact Achilles tendons. We demonstrated an excellent correlation between the clinical and US mapping. This study demonstrates an accurate and repeatable clinical technique for mapping the sural nerve in conjunction with percutaneous Achilles tendon repairs.

Minimal preparation computed tomography instead of barium enema/colonoscopy for suspected colon cancer in frail elderly patients: an outcome analysis study.

AIM: To evaluate the efficacy of minimal preparation computed tomography (MPCT) in diagnosing clinically significant colonic tumours in frail, elderly patients. MATERIALS AND METHODS: A prospective study was performed in a group of consecutively referred, frail, elderly patients with symptoms or signs of anaemia, pain, rectal bleeding or weight loss. The MPCT protocol consisted of 1.5 l Gastrografin 1% diluted with sterile water administered during the 48 h before the procedure with no bowel preparation or administration of intravenous contrast medium. Eight millimetre contiguous scans through the abdomen and pelvis were performed. The scans were double-reported by two gastrointestinal radiologists as showing definite (>90% certain), probable (50-90% certain), possible (<50% certain) neoplasm or normal. Where observers disagreed the more pessimistic of the two reports was accepted. The gold standard was clinical outcome at 1 year with positive end-points defined as (1) histological confirmation of CRC, (2) clinical presentation consistent with CRC without histological confirmation if the patient was too unwell for biopsy/surgery, and (3) death directly attributable to colorectal carcinoma (CRC) with/without post-mortem confirmation. Negative end-points were defined as patients with no clinical, radiological or post-mortem findings of CRC. Patients were followed for 1 year or until one of the above end-points were met. RESULTS: Seventy-two patients were included (mean age 81; range 62-93). One-year follow-up was completed in 94.4% (n=68). Mortality from all causes was 33% (n=24). Five histologically proven tumours were diagnosed with CT and there were two probable false-negatives. Results were analysed twice: assuming all CT lesions test positive and considering "possible" lesions test negative [brackets] (95% confidence intervals): sensitivity 0.88 (0.47-1.0) [0.75 (0.35-0.97)], specificity 0.47 (0.34-0.6) [0.87 (0.75-0.94)], positive predictive value 0.18 [0.43], negative predictive value 0.97 [0.96], positive likelihood ratio result 1.6 [5.63], negative likelihood ratio result 0.27 [0.29], kappa 0.31 [0.43]. Tumour prevalence was 12%. A graph of conditional probabilities was generated and analysed. A variety of unsuspected pathology was also found in this series of patients. CONCLUSIONS: MPCT should be double-reported, at least initially. "Possible" lesions should be ignored. Analysis of the graph of conditional probability applied to a group of frail, elderly patients with a high mortality from all causes (33% in our study) suggests: (1) if MPCT suggests definite or probable carcinoma, regardless of the pre-test probability, the post-test probability is high enough to warrant further action, (2) frail, elderly patients with a low pre-test probability for CRC and a negative MPCT should not have further investigation, (3) frail, elderly patients with a higher pre-test probability of CRC (such as those presenting with rectal bleeding) and a negative MPCT should have either double contrast barium enema (DCBE) or colonoscopy as further investigations or be followed clinically for 3-6 months. MPCT was acceptable to patients and clinicians and may reveal significant extra-colonic pathology.

Technical report. Intra-operative ultrasound-guided needle localization for impalpable testicular lesions.

AIMS: To describe a new technique of intra-operative ultrasound-guided needle localization of impalpable intratesticular lesions. MATERIALS AND METHODS: Three patients with impalpable testicular lesions identified on ultrasound underwent needle localization under ultrasound guidance. The procedure was performed in the operating theatre under general anaesthetic using a 7.5-8 MHz linear array probe and a portable ultrasound machine. Under direct guidance, a 21 G needle was placed through the centre of the lesion allowing resection and immediate frozen section analysis. RESULTS: In two patients malignancy was confirmed and an orchidectomy was performed. In one patient a benign lesion was detected obviating the need for orchidectomy. CONCLUSION: Patients presenting with impalpable testicular lesions can pose a diagnostic dilemma and orchidectomy is often performed. We describe an ultrasound-guided intra-operative localization technique enabling direct pathological examination so surgical approach can be re-evaluated in the presence of a benign lesion. This is particularly important in the case of a solitary testicle in order to preserve testicular function.

Portal venous gas: detection by gray-scale and Doppler sonography in the absence of correlative findings on computed tomography.

Two cases are described in which portal venous gas (PVG) was detectable by ultrasound, but the liver appeared normal on computed tomography (CT). The finding of PVG was associated with ischemic bowel in one case but was a benign finding in the other case. The gray-scale and Doppler ultrasound findings associated with PVG are described. This case report illustrates two key points. First, ultrasound may detect gas within the portal venous system when CT is negative. Second, when PVG is detected on ultrasound, urgent clinical assessment followed by contrast-enhanced CT is indicated to assess for associated intestinal ischemia.

Evidence for the polyp-cancer sequence in gallbladder cancer.

We report a patient with symptomatic biliary disease and who was diagnosed by ultrasound to have a large polypoid gallbladder lesion. Histopathology revealed adenoma in combination with carcinoma in situ. The evidence for the adenoma-carcinoma sequence in gallbladder cancer and diagnostic and therapeutic implications are discussed.

Magnetic resonance imaging of rectal carcinoma: a prospective study.

Accurate preoperative staging of rectal cancer is necessary to identify patients who might benefit from adjuvant therapy. Magnetic resonance imaging (MRI) was evaluated in 20 consecutive patients with rectal cancer undergoing 'curative' surgery. Detailed histopathological examination of the resected lesion was correlated with findings of MRI. MRI staging concurred with histological staging in 18 of 20 patients using the Dukes or tumour node metastasis classification but in only 14 using the modified Astler-Coller system. MRI diagnosed transmural invasion in all but one patient with microscopic mural invasion (positive predictive value, 100 per cent; negative predictive value, 80 per cent; overall accuracy, 95 per cent). MRI correctly diagnosed tumour deposits or involved lymph nodes in 12 patients. MRI overstaged one patient, in whom nodes that were enlarged on imaging studies were negative at histological examination (positive predictive value, 92 per cent; negative predictive value, 100 per cent; overall accuracy, 95 per cent). MRI has a role in selected cases for the preoperative assessment of rectal carcinoma.

Accuracy of computed tomography during arterial portography in the segmental localization of liver tumours.

The ability of computed tomography during arterial portography (CTAP) to identify and segmentally locate 20 hepatic tumours was prospectively assessed in 7 patients undergoing hepatic resection. All eight lesions greater than 2.5 cm in diameter were detected, but only two out of four and two out of eight of those measuring 1-2.4 cm and < 1 cm respectively. The overall segmental localization accuracy for detected lesions was 91%. Our results highlight the insensitivity of CTAP to hepatic lesions smaller than 1 cm in size, but have shown the accuracy of segmental localization for detected lesions.

Color Doppler imaging of the cystic artery.

Color Doppler ultrasonography was used to examine the gallbladder vascular supply in 30 volunteers and in 30 biliary lithotripsy patients pre- and 2 hours posttreatment. A preliminary study of 10 cases of acute cholecystitis was also performed. A cystic artery waveform was obtained in 24 of the volunteers, 18 pre- and postlithotripsy patients, and in 1 of 10 patients with acute cholecystitis. The mean pulsatility indices obtained were 1.04 in the volunteers, 0.98 pre- and 1.02 postlithotripsy (p greater than 0.1). This study shows that the normal gallbladder blood supply can be consistently identified using color Doppler flow imaging and that there is no appreciable difference in the cystic artery pulsatility index following medium-energy shock-wave extracorporeal lithotripsy. Preliminary results in acute cholecystitis suggest that flow is decreased below the sensitivity of the color Doppler imaging system used in this investigation.

The value of sonography in determining cystic duct patency.

A prospective blinded comparison of ultrasonography (US) and oral cholecystography (OCG) was performed in 100 patients with symptomatic gall-stones to determine whether US would enable an accurate assessment of cystic duct patency to be made. Patency of the cystic duct was defined as gall-bladder opacification on OCG or a greater than 20% decrease in gall-bladder volume by US post-fatty meal. The ellipsoid method of volume measurement was used. Any patient who had a non-opacified gall-bladder on OCG but a greater than 20% volume decrease on US had cholescintigraphy performed (DISIDA). Oral cholecystography demonstrated cystic duct patency in 88 patients (88%), and fatty-meal gall-bladder US met the specified study criteria for patency in 86 patients (86%). False negative results were identified in four of the OCG and in six of the US examinations. The results of this study indicate that gall-bladder sonography with a post-fatty meal contraction of greater than 20% is a very accurate predictor of cystic duct patency. A contraction of less than 20%, however, cannot be considered a reliable predictor of cystic duct occlusion.

Radiological investigation in laparoscopic compared with conventional cholecystectomy--an early assessment.

The implications of laparoscopic cholecystectomy (LC) for radiology were assessed by comparing imaging investigations in 48 LC and 48 conventional cholecystectomy (CC) patients. In addition, we attempted to identify findings on pre-operative ultrasound (US) which predicted operative difficulties at LC. There were no per-operative or T-tube cholangiograms in the LC patients, but otherwise the pattern of investigation was similar in both groups. Forty of the 48 CC patients underwent cholangiography (per-operative cholangiography in 36, endoscopic retrograde cholangiopancreatography (ERCP) in two, and both in two) demonstrating calculi in eight (16.7%) cases. Only four LC patients had cholangiography (ERCP in all cases) demonstrating common bile duct (CBD) calculi in one (2.1%) case. Ultrasound failed to identify the gall-bladder with certainty in three of the five failed LC cases. Neither gall-bladder wall thickness, contraction nor calculus size on pre-operative US served as predictors of other per-operative difficulties. Our results indicate that there may be some patients with retained CBD calculi in the LC group. The role of pre-operative US in predicting operative difficulties needs further assessment in a prospective study.

Case report: multiple hepatic and pulmonary haemangioblastomas--a new manifestation of von Hippel-Lindau disease.

Capillary haemangioblastomas rarely occur outside the central nervous system and have not been described previously in the lung or liver. We describe such lesions developing in a patient with von Hippel-Lindau complex who previously had cerebellar and spinal haemangioblastomas resected.

Cutaneous seeding following fine needle biopsy of colonic liver metastases.

Needle track seeding is a rare complication of percutaneous needle biopsy which has become less frequent with the advent of the fine needle. We describe one case of malignant cutaneous seeding following fine needle aspiration of a peripherally based hepatic metastasis from colonic carcinoma. This report underlines the need to traverse normal adjacent liver parenchyma prior to entering a peripherally-based metastatic deposit to reduce the likelihood of malignant cutaneous seeding.

Fatal carcinoid crisis after percutaneous fine-needle biopsy of hepatic metastasis: case report and literature review.

Immediately after a fine-needle aspiration biopsy (FNAB) was performed of a carcinoid liver metastasis, a patient had severe flushing, nausea, and faintness, followed by generalized seizure activity, profound hypotension, and cardiopulmonary arrest refractory to resuscitative efforts. This was considered due to massive release of vasoactive substances into the systemic circulation, caused by manipulation of the tumor at biopsy and aggravated by resuscitative efforts. Hypotensive crisis should be considered a potential, although unusual, complication of FNAB of liver metastases in patients with carcinoid syndrome. If biopsy is necessary, an intravenous access line should be established before biopsy is performed, and personnel should be prepared to administer emergency resuscitation. Medication with a somatostatin analogue before biopsy is performed is suggested. Catecholamine administration should be avoided.

Carcinoma of the gallbladder: a risk associated with gallbladder-preserving treatments for cholelithiasis.

Five cases of carcinoma of the gallbladder associated with nonsurgical treatment of cholelithiasis are presented in view of the recent interest in gallbladder-preserving procedures. Three patients developed gallbladder cancer that was diagnosed 4, 11, and 72 years, respectively, after cholecystostomy. One other patient had gallbladder carcinoma diagnosed 7 months after extracorporeal shock wave lithotripsy for common bile duct stones. The tumor was probably present but not identified at the time of lithotripsy. The last patient had undiagnosed gallbladder malignancy at the time of cholecystostomy for treatment of acute calculous cholecystitis. Gallbladder carcinoma has been reported in 1% of patients undergoing cholecystectomy, and the risk of carcinoma developing in patients with asymptomatic cholelithiasis has been estimated at less than 1%. These figures should not diminish the role of gallbladder-preserving treatments in elderly and selected high-risk patients for whom cholecystectomy may be hazardous. However, such patients must undergo a thorough imaging assessment both before and after treatment to ensure that a gallbladder carcinoma is not overlooked.