[Computerized tomography of the meniscus with a stress device]

PURPOSE

We investigated the usefulness of a mechanical stress device to increase widening of the articular rima in CT studies of the meniscus on forced varus and valgus.

MATERIAL AND METHODS

September 1997 to October 1998, we examined 284 patients with symptoms and clinical signs of meniscal injury. CT was performed during forced varus and valgus, depending on the site of the suspected damage, in 70 of 284 patients. We used an FOV of 18 cm, with a potential difference of 140 kVp and power of 170 mA. The reconstruction matrix was 512 x 512 and acquisition time was 3 s. A set of 8-10 partially overlapping scans were acquired craniocaudally, with slice thickness of 1.5 mm and gap of 1 mm. The mechanical strainer was locked in the correct position and a second set of 4-5 images acquired at the meniscus. Then the patients were submitted to arthroscopy to check the radiological findings.

RESULTS

CT performed in forced varus and valgus had 96.8% specificity, 97.3% sensitivity and 97.1% diagnostic accuracy. Sensitivity was 100%, specificity 96% and diagnostic accuracy 98% in the medial meniscus, while we had 88.9%, 100% and 94.7% respectively in the external meniscus.

CONCLUSIONS

CT with a mechanical stress device was extremely useful in defining the meniscal loose edge. It also showed the exact shape and complexity of meniscal injury, even in the cases with narrow articular rima or those where conventional CT had performed poorly.

Uneven distribution and size of rabbit lens capsule proteoglycans

To document the ultrastructural distribution of lens capsule proteoglycans, rabbit lens capsules were fixed and stained overnight in 50 mM sodium acetate, pH 5.6, containing 2.5% glutaraldehyde, 0.2% Cuprolinic Blue and 0.2 M MgCl2. They were rinsed, stained with 1% aqueous sodium tungstate, embedded in Epon, sectioned (60 nm), and examined with an electron microscope at 60 kV. Proteoglycan-Cuprolinic Blue complexes mainly appeared as networks of small electron-dense filaments throughout the posterior and anterior capsules. The posterior capsule was a single layer with a network of small proteoglycan filaments gradually decreasing in size from the humoral side (90 x 10 nm) to the lenticular side (30 x 8 nm). The humoral side of the anterior capsule had a thin lamina (400 nm) containing large (180 x 40 nm), very electron-dense proteoglycan-Cuprolinic Blue complexes plus small proteoglycans. Below this lamina, the complexes were only seen as filaments slightly smaller than those in the corresponding area of the posterior capsule. Cuprolinic Blue binding of the anterior and posterior lens capsules revealed differences in the size and distribution of their sulphated proteoglycans which do not correspond to the patterns of their immunoreactivity with anti-heparan sulphate proteoglycan. The humoral lamina in the anterior capsules, with large proteoglycan structures, might be a distinct structural and functional compartment.

[High-resolution ultrasonography in the study of carpal tunnel syndrome]

We investigated the reliability of some US signs in the diagnosis of the carpal tunnel syndrome. We carried out a single-blind study with 13-MHz high resolution probes and electromyography on 132 patients with clinical evidence of the carpal tunnel syndrome; a control group of 20 asymptomatic patients was also submitted to US. Eighty-six of 107 patients with US signs of the carpal tunnel syndrome were then submitted to surgical decompression (resection of the transverse carpal ligament), while the extant 21 patients underwent conservative treatment and clinical follow-up. To diagnose the carpal tunnel syndrome, we considered the following US patterns: median nerve changes (swelling before its entrance into the carpal tunnel and flattening in the tunnel itself), palmar bowing of the flexor retinaculum, thickening of the transverse carpal ligament and increased depth of the carpal tunnel, as measured from the apex of the transverse carpal ligament convexity to the underlying carpal bone. Median nerve changes were unreliable signs and were missing in many cases: only 45 of 107 patients exhibited median nerve swelling before and/or its flattening in the carpal tunnel (42%). Such indirect signs as the thickening of the transverse carpal ligament in chronic cases were demonstrated in 94 of 107 patients with the carpal tunnel syndrome (88%) and canal deepening in all unilateral carpal tunnel syndromes was shown in 92 of 107 patients (87%); both these signs proved to be much more reliable. The palmar bowing of the flexor retinaculum was also difficult to demonstrate in surgical patients or in those with connective tissue fibrosis within the tunnel: this sign was demonstrated in 80 of 107 patients with the carpal tunnel syndrome confirmed with electromyography (75%). Tanzer and Rietze reported median nerve changes observed at surgery in 43% and 66% of their patients, respectively. Recent MR findings in asymptomatic wrists have demonstrated that the normal median nerve has an elliptical shape inside the carpal tunnel. To conclude, high resolution US exhibited 96% sensitivity, 95% specificity and 93% diagnostic accuracy and proved to play a major role in the diagnosis of the carpal tunnel syndrome.

[Role of Doppler color in the differential diagnosis of benign and malignant adenopathies]

The diagnosis of enlarged lymph nodes is of the utmost importance especially in the treatment planning of cancer patients. US yields such morphological findings as node size, longitudinal/transverse diameter ratio, hilum visibility and cortical thickness, which however do not permit the differential diagnosis of benign from malignant forms. Some authors tried to distinguish inflammatory enlargement from metastatic forms on the basis of color Doppler findings, with conflicting and questionable results. We investigated the potentials of color Doppler US in the differential diagnosis of benign and malignant lymph node enlargement using morphological data and flow measurements in lymphatic hilum vessels. The palpable superficial lymph nodes of 70 patients were studied with color Doppler with a linear probe (7.5-10 MHz) equipped for Doppler flow measurements. The largest lymph node was studied in multiple enlargement. The final diagnosis was made with US-guided cytology and/or excisional biopsy. The venous hilar vessels were depicted with color Doppler US in 44/45 patients with lymphadenitis and only in 1/17 patients with metastatic enlargement. Spectral Doppler exams of the hilar arteries showed flows with a wide telediastolic component in lymphadenitis (relative RI:0.58), while flow was rapid and with poor telediastolic component (relative RI:0.84) in metastatic enlargement. Average RI was 0.62 in Hodgkin's lymphomas and 0.71 in all the other lesions. We conclude that the distortion and compression of the main hilar vessels in metastatic lymph node enlargement often prevents color Doppler depiction of venous vessels. Moreover, the compression and distortion of the intranodal capillary network (the "mass" effect) often results in increased RI, as detected with power Doppler in the lymphatic hilum. Even though color Doppler US studies of the hemodynamic changes in the hilar vessels need further validation in larger series of cases, our preliminary results suggest interesting potentials in distinguishing inflammatory from metastatic enlargement, which differentiation remains nevertheless difficult especially in Hodgkin's lymphoma.

Migration of metallic clips used during laparoscopic cholecystectomy and formation of gallstones around them: surgical implications from a prospective study

Two groups of patients, with laparoscopic cholecystectomy (LC) were prospectively studied. All patients had serial plain abdominal X-ray examinations at various intervals after operation, to record the position of clips placed during LC. Seventy-one patients had less cystic duct (CD) dissection and > or =4 clips placed during the procedure. One hundred and fifteen patients had a larger CD dissection and only 4 clips placed (2 on the cystic artery and 2 on the CD, without additional clips on smaller vessels). In the former group, 7 patients had clip migration within 1 month and 11 within 1 year vs 1 either at 1 month or 1 year in the latter group (p = 0.01 and <0.001, respectively). During the follow-up, a 72-year-old man belonging to the former group had a recurrent common duct brown pigment stone containing a metallic clip 26 months after operation. He was treated successfully by endoscopic sphincterotomy. Factors predisposing to clip migration were short cystic stump, inadvertent clip dislodgment or incorrect placement, cystic duct ischemic necrosis, and local suppurative complications. Data from 29 patients with GS formed around suture material or phytobezoars observed during a prospective study and from the physicochemical and structural analysis of a cumulative series of 64 GS containing foreign bodies are also presented and discussed. It is suggested that metallic clips can migrate from their initial sites at various intervals within the peritoneal cavity or into the common duct and serve as a nidus for GS formation. Metallic clip migration in most cases is due to technical factors and can usually be prevented. However, it is not possible to prevent either clip migration or GS formation in every case, since even well-placed clips can migrate due to suppurative complications or local ischemic damage, and, once that penetration within the bile tract has occurred, GS are usually going to form, irrespective of the nature and the shape of the foreign body.

Case report: sequential bilateral carotid dissection leading to Raeder's syndrome

A 39-year-old man complained of unilateral headache, diplopia and marked anterior neck oppression "like a necklace". MRA was used to study this case of subsequent bilateral internal artery dissection (ICAD) which initially appeared as Raeder's syndrome. MRA proved to be a non-invasive alternative for studying stenosis, occlusions and dissections of the intracranial and extracranial vessels.

[The determination of BB genotype of vitamin D receptors identifies patients at risk for osteoporosis]

The gene responsible for peak bone mass has been recently identified as the gene coding for the Vitamin D Receptor (VDR); there exist two alleles, termed "B" and "b", determining a typical allelic polymorphism. We determined the VDR genotype of 50 young post-menopausal women (mean age: 56 years), and measured bone density by Dual Energy X ray Absorptiometry (DEXA) twice: at the beginning of the study and after one year. VDR genotype was determined using the DNA extracted from hair cells, thus avoiding the use of blood samples. The frequency of VDR genotypes (BB or bb homozygous; Bb heterozygous) was approximately the same in the two groups of subjects (i.e., normal controls and osteoporotic women). The bone density of normal subjects (36) was measured for the second time one year after the first measurement. All BB homozygous subjects showed significantly decreased bone density values; 50% of them showed values below 0.750 g/cm2 at the second measurement, thus being classified as osteoporotic. However, neither bb homozygous nor Bb heterozygous subjects showed any significant decrease in bone density values (about 4% of the initial value). Therefore, determining the VDR genotype was critical for identifying the subjects who were normal at the first measurement, but had markedly decreased bone density values later, thus being at risk of developing osteoporosis.

[Interstitial photocoagulation with laser in the treatment of liver metastasis]

Interstitial laser photocoagulation (ILP) causes tumor necrosis with local hyperthermia produced by laser light energy. We treated with US-guided ILP 14 patients (7 men and 7 women; mean age: 67 years) and 20 metastases: 9 of them were < 3 cm in max. diameter and 11 were > 3 cm (mean diameter: 2.9 cm); 14 metastases were from colon carcinoma, 5 from breast cancer and 1 from lung cancer. ILP was performed with 300 and 600 microns quartz fiberoptic guides advanced in 21-18G Chiba needles and a continuous-wave Nd: YAG laser with 1064 nm wavelength. We used single expositions of 5-6 minutes with an irradiation power of 5 watts and scheduled 3 treatment sessions, performing CT scans and biopsies at the end of each session. The extent of induced necrosis was classified as follows on the basis of CT findings: grade 1 = 100% necrosis; grade 2 = necrosis > 50%; grade 3 = necrosis < 50%. The average follow-up was 6 months. After the 3 scheduled treatment sessions, CT showed grade 1 necrosis in all the lesions < 3 cm in diameter and in 4/9 (44%) lesions > 3 cm and grade 2 and 3 necrosis in the remaining cases (necrosis > 50% in 95% of the lesions and 92% of the patients). The cytologic findings were in agreement with CT results in all grade 2 and 3 cases, but in one grade 1 necrosis cytology showed residual viable tumor. To conclude, ILP is a safe and well-tolerated procedure. Maximum efficacy was observed in the lesions < 3 cm, while lesion volume was markedly reduced in the lesions > 3 cm. US is a useful tool in the real-time monitoring of this procedure and CT is the most accurate imaging technique to assess treatment efficacy.

[Ileal occlusion with strangulation: importance of ultrasonography findings of the dilated loop with intraluminal fluid-fluid resulting from sedimentation]

To identify some dynamic or morphological patterns for the diagnosis of small bowel obstruction by hernia, adhesions or volvulus, we submitted to ultrasonography (US) 61 patients with clinical and radiographic syndromes of mechanical small bowel obstruction. The cause of obstruction was demonstrated in 58 patients-namely, with surgery in 56 patients and further instrumental examinations in 2. Three patients died before surgery. In our series, small bowel obstruction with strangulation was demonstrated at surgery in 31/56 patients. In 27/31 patients, US showed the coexistence of dilated loops with different kinetic behavior in the abdominal cavity-i.e., the simultaneous presence of akinetic loops with an intraluminal fluid-fluid level by sediment and peristaltic loops with solid particles in suspension. In 4/31 patients with strangulating small bowel obstruction. US provided no useful elements to explain the mechanism of obstruction. The US pattern of fluid-fluid levels due to intraluminal sediment in all the intestinal mass above the occluded segment was observed in 6/6 patients with uncompensated mechanical intestinal obstruction. This sign is due to the absence of intestinal muscular activity in the late stages of mechanical intestinal obstruction; its value is purely prognostic. To conclude, the US pattern of fluid-fluid levels by sediment diffused in the whole intestinal mass provides no useful elements to explain the cause of obstruction: on the contrary, the US pattern characterized by isolated intraluminal fluid-fluid levels or by the association of akinetic and peristaltic loops in the abdominal cavity appears pathognomonic of strangulating obstruction caused by volvulus, adhesion or hernia, with 87% sensitivity and 100% specificity.

[Color Doppler echography in the study of obstruction-related lung collapse]

The typical US pattern of obstructive atelectasis consists in a triangular hypoechoic area with anechoic bands inside related to fluid-filled bronchial structures--the US fluid bronchogram sign. According to some authors, this US sign within a chest mass indicates pulmonary parenchyma disease. Furthermore, it suggests the diagnosis of lung collapse. Sixty-one patients with obstructive atelectasis confirmed with conventional radiography, conventional and computed tomography, and bronchoscopy were submitted to B-mode and color-Doppler US to assess the importance of the US fluid bronchogram sign in obstructive pulmonary atelectasis. In this condition, B-mode US showed tubular anechoic bands in 59/61 patients. Power Doppler venous sampling showed a Doppler spectrum with marked phase oscillations. Arterial sampling showed a Doppler spectrum with high distal impedance-with poor or totally absent diastolic component. To conclude, in the atelectasis area, B-mode US showed in 96% of patients some anechoic bands with no apparent pulsatility. Color-Doppler showed color flow in 100% of cases, which confirmed the vascular nature of the masses. Thus, the US fluid bronchogram, which is frequently described in the literature, was never observed in our series. Power Doppler spectral flow analysis can be useful in the diagnosis of obstructive atelectasis because it depicts the hemodynamics of atelectasis parenchyma. Indeed, the arterial spectrum with high distal resistance is consistent with the effects of hypoxia on intra-atelectatic blood vessels. Further research is necessary to assess the role of color-Doppler US in the hemodynamic study of intra-atelectatic vessels. However, our preliminary results open new perspectives for the acquisition of physiopathologic data on abnormal blood flow in obstructive atelectasis.

[Magnetic resonance in the study of the facial nerve: methodological approach and normal anatomy]

The authors report their experience in the study of facial nerve anatomy by means of MR Imaging. The seventh pair of cranial nerves was studied in 6 healthy and informed volunteers with a super-conductive MR unit at 0.5 T using surface and head coils. Slices were 3 mm thick and were acquired on the axial and sagittal planes, when the petrous and the mastoid bones were studied. The parotid gland was studied with 5-mm slices acquired on the axial, angled axial, and sagittal planes. In all cases T1-weighted images (TR 450, TE 30) were performed. If the above research protocol, which is relatively simple and direct, is applied, the whole course of the facial nerve up to its main distal branches can be almost completely demonstrated.

Sonography of vertebral arteries in De Kleyn's position in subjects and in patients with vertebrobasilar transient ischemic attacks

Two groups of subjects, matched for age, were studied. The first group consisted of 190 healthy subjects, the second, of 60 patients with vertebrobasilar transient ischemic attacks (TIAs), 22 of whom underwent angiography. After it was ascertained that the findings from continuous-wave (cw) Doppler of carotid and vertebral arteries, performed in the standard position, were normal, the examination was then done in De Kleyn's position, the velocity signal being detected at the mastoidal slopes. The abnormal findings were classified into two groups: "loss of diastolic velocity signal" and "absence of velocity signal." In the control group, changes of flow were detected in 6.31%, whereas in the group of patients abnormal Doppler parameters were detected in 33.33%. None of the patients who were submitted to angiography showed abnormal hemodynamic findings. The authors suggest that the detection of the velocity signal of the vertebral arteries in De Kleyn's position could be of help in revealing conditions that could cause, in time, signs and/or symptoms of vertebrobasilar insufficiency in subjects with possible asymptomatic anomalies of the circle of Willis.

Treatment of urinary fistulas after resection of horseshoe kidneys by selective arterial embolization

Two patients presenting with urinary fistulas following partial resection of hydronephrotic kidneys were successfully treated with selective arterial embolization causing functional ablation of the remaining renal parenchyma. This technique is simpler than surgical reexploration.

Digital subtraction angiography of right cervical aortic arch

This report describes a 7 year old boy with a history of recurrent respiratory infections, a 3/6 ejection systolic murmur and a right supraclavicular systolic thrill. Chest x-ray showed widening of the superior mediastinum towards the right, and barium esophagram demonstrated anterior displacement and compression of the esophagus. Cross-sectional echocardiography revealed a transverse aortic arch segment. Thus, the findings described above suggested the noninvasive diagnosis of the right cervical aortic arch. A peripheral intravenous digital subtraction angiography was necessary to evaluate the origin of the epi-aortic arteries and it proved adequate for the follow-up of these patients.

Continuous-wave Doppler of vertebral arteries in noninvasive diagnosis and management of vertebro-basilar TIAs

Continuous-wave Doppler and angiography of the vertebro-basilar system were used in 38 patients with vertebro-basilar transient ischemic attacks. 63 vertebral arteries were studied. Among 47 normal Doppler parameters, 46 were confirmed by angiography. The sonographic diagnostic procedure showed a very high negative predictive value (97.87%), while the positive predictive value was relatively low (56.25%). Data from literature were reviewed. The authors suggest that when Doppler of vertebral arteries is negative, there is a very low probability that a follow-up angiography will reveal pathologic conditions calling for a surgical approach.

[Cystic dilatation of the bile ducts : value of various methods of diagnosis. Apropos of 3 cases]

Three cases of cystic dilatation of the biliary tract of 1st, 4th and 5th type are reported here according to the classification established by Longmire and Hadad amended. In two patients the diagnosis was carried out through ultrasound examination and confirmed, in one case, by intraveinous cholangiography associated to computed tomography (and by peroperatory cholangiogram in the other one). In the third patient suffering from Caroli's disease the diagnosis was carried out during peroperating cholangiography. The possibilities of the different methods in diagnosing cystic dilatations of the biliary tract are discussed and therapeutic problems are taken into consideration.

Leiomyosarcoma of the kidney: report of two cases with common angiographic findings

Two cases of renal leiomyosarcoma are described. At angiography both cases presented common findings consisting of: (1) central hypovascularity surrounded by peripheral tumor neovascularity and (2) oval-shaped areas that rapidly filled with contrast medium. This angiographic appearance, although not previously described in such tumors, cannot be claimed to offer a key to preoperative diagnosis because it may be found in the more common hypernephromas with central necrosis.

Angiographic aspects of renal cell carcinoma metastatic to the female genitalia

Selective angiography of the hypogastric artery was performed in two patients presenting vaginal metastases from renal cell carcinoma, in order to better define the extent of the metastases. In other case left renal angiography revealed an unsuspected metastasis to the left ovary, fed by a middle perforating capsular artery.

Effects of streptozotocin in the WDHA syndrome not amenable to radical surgery

Two cases of Verner-Morrison syndrome due to pancreatic carcinoma were treated H. h streptozotocin (STZ) according to the schedule suggested by the Division of Cancer Treatment of the National Cancer Institute. In both patients the drug caused a remission of the WDHA syndrome: therefore, this finding seems to recommend such treatment when the syndrome is not amenable to radical surgery. Renal toxicity is, however, an important limitation. It occurs mostly when STZ is administered by iv infusion. In one of the patients, after a serious impairment of renal function caused by STZ, prednisone controlled the syndrome for a long period of time.

Effects fo streptozotocin in the WDHA syndrome not amenable to radical surgery

Two cases of Verner-MOrrison syndrome due to pancreatic carcinoma were treated H. h streptozotocin (STZ) according to the schedule suggested by the Division of Cancer Treatment of the National Cancer Institute. In both patients the drug caused a remission of the WDHA syndrome: therefore, this finding seems to recommend such treatment when the syndrome is not amenable to radical surgery. Renal toxicity is, however, an important limitation. It occurs mostly when STZ is administered by iv infusion. In one of the patients, after a serious impairment of renal function caused by STZ, prednisone controlled the syndrome for a long period of time.

Functional renal alterations in chronic liver diseases

83 patients with chronic active hepatitis (CAH), 38 of them with cirrhosis, were studied and compared with 10 control subjects suffering from chronic persistent hepatitis (CPH). Tubular acidosis frequently was found in our cases. Renal plasma flow and glomerular filtration rate were significantly decreased in CAH when compared with CPH. Selective renal arteriography showed evident decrease of arterial flow in the outer cortex. Selective renal scan with 99mTc microspheres of human albumin showed a frequent escape of the tracer from the kidney to the lung. PGE1 and PGE2 levels appeared higher in the renal artery than in the vein and were significantly more elevated in 9 cases with cirrhosis vs. 13 controls. These results suggest the frequent functional impairment of the kidney also in the early stages of CAH, with an increase of PGE levels and an opening of intrarenal shunts.

[Role of phlebography in the radiodiagnosis of aneurysms of the limbs (author's transl)]

Three observations of peripheral aneurysms complicated by venous compression or thrombosis are reported. The clinical and angiographic patterns referred to popliteal, femoral and subclavian localization suggest the role of phlebography in all cases of aneurysms of the limbs.