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N J Smits

Publications and source records attributed to N J Smits.

At least 19 recordsLinked to original sources
PubMed2001

A randomized trial comparing levothyroxine with radioactive iodine in the treatment of sporadic nontoxic goiter.

A randomized clinical trial was performed in consecutive patients with sporadic nontoxic nodular goiter to compare efficacy and side effects of iodine-131 ((131)I) therapy with suppressive levothyroxine (L-thyroxine) treatment. Sixty-four patients were randomized after stratification for sex and menopausal age to receive (131)I (4.44 MBq/g thyroid; group A) or suppressive L-thyroxine treatment aiming at TSH values between 0.01 and 0.1 mU/L (group B). The main outcome measurements after 2 yr were goiter size by ultrasound, serum thyroid function tests, markers of bone turnover, and bone mineral density (BMD). Fifty-seven patients completed the trial. Goiter size was reduced after 2 yr by 44% in group A and by 1% in group B (P< 0.001). Nonresponders (goiter reduction <13%) were 1 of 29 patients in group A and 16 of 28 patients in group B (P = 0.00001). In responders, goiter reduction in group A (46%) was greater than in group B (22%; P< 0.005). In group A, 45% of patients developed hypothyroidism. In group B, 10 patients experienced thyrotoxic symptoms, requiring discontinuation of treatment in 2 (in 1 because of atrial fibrillation). Markers of bone formation and bone resorption increased significantly in group B, related to a mean decrease of 3.6% of BMD at the lumbar spine after 2 yr (from 1.09 +/- 0.22 to 1.05 +/- 0.23 g/cm(2); P< 0.001), both in pre- and postmenopausal women. No changes in BMD were observed in group A. In conclusion, (131)I therapy is more effective and better tolerated than L-thyroxine treatment in patients with sporadic nontoxic goiter. Suppressive L-thyroxine treatment results in significant bone loss.

Bone Density↗
PubMed1999

Imaging and staging of biliopancreatic malignancy: role of ultrasound.

Most patients with a pancreatic head carcinoma, periampullary carcinoma or a cholangiocarcinoma of the liver hilum (Klatskin tumor) present with obstructive jaundice and therefore ultrasound often is the first imaging modality. Visualization is sufficient in more than 90% of cases for adequate diagnosis and staging. Even most small papillary tumors can be diagnosed with conventional abdominal ultrasound. In pancreatic head and periampullary carcinoma vascular involvement is the most important determinant for local irresectability and can often be assessed by color Doppler US. An abnormal pulsed Doppler signal obtained from the portal venous system due to severe narrowing or occlusion is highly suspicious for major involvement and irresectability of the tumor. However, a normal pulsed Doppler signal does not exclude involvement, if the tumor has continuity with the vessel with interruption of the hyperechoic tumor vessel interface. Enlarged lymph nodes are not a major diagnostic parameter, because a reliable differentiation between reactive and malignant lymph nodes is generally not possible. Very tiny liver and peritoneal metastases are missed by abdominal US and only detectable by laparoscopy and/or laparascopic US. In cholangiocarcinoma of the liver hilum extensive biliary and vascular involvement are considered the most important factors for determining irresectability. Portal venous involvement can be assessed by color Doppler US with a high accuracy (91%). Although cholangiography (ERCP and PTC) is considered the best imaging modality in detecting proximal extension of the tumor into the biliary system US can provide useful additional information. If dilated ducts are seen without clear communication among each other within a liver lobe, extension of the tumor into the segmental bile ducts can be concluded. We consider color Doppler US, a valuable tool for preoperative imaging and staging of biliopancreatic malignancy.

Bile Duct Neoplasms↗
PubMed1998

Lean body mass as a determinant of thyroid size.

OBJECTIVE: Males have a larger thyroid gland than females, and this has been related to the difference in body weight. In view of the different body composition of men and women, we hypothesized that lean body mass is a better determinant of thyroid volume than body weight. DESIGN: A cross-sectional study in an area not deficient in iodine. SUBJECTS: 44 non-obese healthy adults (group I, 21 men, 23 women with equal distribution of sexes in age groups between 21 and 70 years) and 20 adults with marked obesity (group II, 8 men, 12 women, BMI > 30 kg/m2) were studied. None used medication and all had normal thyroid function tests. MEASUREMENTS: Thyroid volume was measured by ultrasonography, and lean body mass with a body impedance analyser. RESULTS: The thyroid volume in men was larger than in women in both groups; it was also larger in the obese than in the non-obese subjects. In the nonobese subjects, thyroid volume was related both to body weight (r = 0.42, P < 0.005) and to lean body mass (r = 0.55, P = 0.0001). In the obese subjects, thyroid volume was no longer related to body weight (r = 0.23, NS) but was still correlated with lean body mass (r = 0.54, P = 0.01). Taking both groups together, the correlation between thyroid volume and lean body mass (r = 0.64, P < 0.001) was stronger than between thyroid volume and body weight (r = 0.50, P < 0.001). Thyroid volume was also related to body length (group I, r = 0.42, P < 0.005; group II, r = 0.54, P = 0.01), but to body-surface area only in the non-obese subjects (group I, r = 0.45, P < 0.01; group II, r = 0.38, NS). The larger thyroid size in the obese was associated with slightly but significantly higher TSH and lower free T4 serum concentrations as compared to the non-obese subjects. CONCLUSIONS: In healthy adults, lean body mass rather than body weight explains the differences in thyroid volume between males and females and between obese and non-obese subjects. Lean body mass appears to be a major determinant of thyroid size.

Adult↗
PubMed1998

Ultrasonographic versus scintigraphic measurement of thyroid volume in patients referred for 131I therapy.

The activity of 131I to be administered as therapy to patients with thyroid disease is usually calculated from 24 h radioiodine uptake and thyroid volume. The aim of the present study was to compare thyroid volume, measured by scintigraphy and ultrasonography, to evaluate the impact of these methods on the calculated 131I dose. Forty patients (20 with diffuse toxic goiter and 20 with multinodular toxic or nontoxic goiter) were investigated. On the same day, thyroid volume was measured by ultrasonography (using transverse scans at 5 mm intervals) and by scintigraphy, using either the ellipsoid formula (SC-E: [symbol: see text]/6 x height x width x depth) or the Himanka formula (SC-H: 0.33 x (planimetric surface in pixels)3/2). With ultrasonography, the size of diffuse goiters was smaller than that of nodular goiters (median values and range: 18 ml (11-46) and 50 ml (14-198) respectively, P < 0.001). Both scintigraphic methods, however, failed to demonstrate a significant difference between diffuse and nodular goiter size. In patients with diffuse goiter, thyroid volume measured by SC-E did not differ from that measured by ultrasonography, whereas thyroid size was overestimated by 53% using the Himanka formula. In contrast, in patients with nodular goiter, thyroid volume measured by SC-H did not differ from that measured by ultrasonography, whereas the ellipsoid formula underestimated thyroid size by 48%. The overestimation of diffuse goiter size by the Himanka formula resulted in a relatively modest median excess of 96 MBq (range -118 to +248 MBq) of the calculated 131I dose. The underestimation of nodular goiter size by the ellipsoid formula resulted in a calculated dose that was 278 MBq lower (range -1624 to +141 MBq). The median calculated 131I dose based on the Himanka formula was not different from that based on ultrasound, but large differences in calculated 131I dose (up to 1280 MBq) were found in individual cases. In conclusion, thyroid volume can be assessed with accuracy by scintigraphy using the ellipsoid formula in patients with diffuse goiter. Wide differences, however, are observed in the size of nodular goiters measured by scintigraphy and ultrasonography.

Adolescent↗
PubMed1997

[Pre- and postoperative irradiation in the treatment of resectable Klatskin tumours].

Proximal bile duct carcinoma (Klatskin tumour) is infrequent and difficult to treat. In principle, surgery is indicated. The usefulness of irradiation after resection is controversial in the literature. This article describes the experiences gained in the Academic Medical Centre of Amsterdam with pre- and postoperative irradiation of resectable Klatskin tumours. Preoperative irradiation (10.5 Gy) is administered to devitalize detached tumour cells in the bile, to prevent implantation metastases after resection. Postoperative irradiation has been administered since 1986 according to protocol. An analysis of 71 patients, of whom 48 had been irradiated after resection while 23 had not, showed a statistically significant prolongation of survival in the group irradiated postoperatively. Radiotherapy was administered externally (55 Gy) or in combination with internal radiotherapy (45 Gy external, 10 Gy internal). For internal irradiation, the source of radiation (Iridium-192) was introduced along the bile duct anastomoses via the soma formed by the blind end of the Roux-Y jejunal loop used for bile duct reconstruction. Since internal irradiation in combination with external irradiation caused more complications, while there was no difference of survival from patients only irradiated externally, the complete postoperative irradiation is currently being given from the outside. Pre- and postoperative irradiation may contribute to the success of the treatment of the resectable Klatskin tumour.

Bile Duct Neoplasms↗
PubMed1997

Incidence and clinical findings of benign, inflammatory disease in patients resected for presumed pancreatic head cancer.

BACKGROUND: The differentiation between cancer and benign disease in the pancreatic head is difficult. The aim of this study was to examine common features in a group of patients that had undergone pancreatoduodenectomy for a benign, inflammatory lesion misdiagnosed as pancreatic head cancer. METHODS: Among 220 pancreatoduodenectomies performed on the suspiscion of pancreatic head cancer, an inflammatory lesion in the pancreas or distal common bile duct was diagnosed in 14 patients (6%). Of these patients, all preoperative clinical information and radiologic images (ultrasound, endoscopic retrograde cholangio-pancreaticography [ERCP]) were critically reassessed. For each examination, the suspicion of cancer was scored on a 0/+/++ scale. RESULTS: Clinical presentation (pain, weight loss, jaundice) raised a suspicion of cancer in 12 patients. On ultrasound, a tumor (mean size: 2.8 cm) was found in the pancreatic head in 13 patients; 12 of 14 ultrasound examinations raised a suspicion of cancer. ERCP showed a distal common bile duct stenosis (length: 1 to 4 cm), stenosis of the pancreatic duct (length: 1 to 5 cm), or a "double duct" stenosis, suspicious for cancer in 13 evaluable patients. The overall index of suspicion was + in seven patients and ++ in seven patients, confirming the initial interpretation of preoperative data. CONCLUSION: When undertaking pancreatoduodenectomy for a suspicious lesion in the pancreatic head, it is necessary to expect at least a 5% chance of resecting a benign, inflammatory lesion masquerading as cancer.

Cholangiopancreatography, Endoscopic Retrograde↗
PubMed1997

Value of laparoscopic ultrasonography in staging of proximal bile duct tumors.

The additional value of laparoscopic ultrasonography was evaluated prospectively in 35 patients undergoing diagnostic laparoscopy for a suspected potentially resectable proximal bile duct tumor. Findings were compared with transabdominal ultrasonography, laparoscopy, surgery, and pathology. Laparoscopic ultrasonography was able to visualize the presence and origin of small bile duct tumors or stones and small liver metastases, which could not be seen or could be visualized only doubtfully by ultrasonography and laparoscopy. Laparoscopic ultrasonography was more useful in staging of small tumors of the gallbladder or proximal common bile duct than in staging bifurcation (Klatskin) tumors. Additional information provided by laparoscopic ultrasonography led to a change in diagnosis or tumor stage in eight patients (23%) and to avoidance of laparotomy in three patients (9%).

Adult↗
PubMed1996

Comparison of laparoscopic and transabdominal ultrasonography in staging of cancer of the pancreatic head region.

The value of laparoscopic ultrasonography in the staging of cancer of the pancreatic head region was compared prospectively to that of transabdominal ultrasonography. Eighty patients underwent LUS, after ultrasonography had shown normal Doppler findings of portal vessels and no signs of metastatic disease. Presence of hepatic or lymph node metastases and vascular tumor infiltration were evaluated in 74 and 48 patients, respectively. Laparoscopic ultrasonography showed liver metastases in 10 patients (14%). Specificity and positive predictive value for the laparoscopic technique determining vascular ingrowth were 97% and 92%, respectively, versus 89% and 77% by sonography in patients with normal Doppler findings (difference not statistically significant). Laparoscopic ultrasonography has shown improved detection of hepatic metastases compared to sonography, but it still must prove its value, as compared to noninvasive methods, in local staging.

Adult↗
PubMed1995

Diagnostic laparoscopy combined with laparoscopic ultrasonography in staging of cancer of the pancreatic head region.

The aim of this study was to assess the additional role of diagnostic laparoscopy combined with laparoscopic ultrasonography in the staging of patients with pancreatic head malignancy. Between January 1993 and June 1994, 73 patients with stage I cancer of the pancreatic head determined by preoperative investigation (endoscopic retrograde cholangiopancreatography and Doppler ultrasonography) were eligible for laparoscopic ultrasonography. The peritoneal cavity was investigated for peritoneal deposits, intrahepatic metastases, malignant infiltration of the portal and superior mesenteric vessels, and N3 lymph node metastases. All patients without histologically proven metastases proceeded to laparotomy. Seventy patients were eligible for evaluation. Sixteen of the 21 patients with distant metastases were diagnosed by laparoscopy with ultrasonography. Forty-nine patients had surgical exploration and trial dissection to assess local resectability. Twenty-nine patients (41 per cent) had resectable pancreatic head tumours. The positive predictive value of local ingrowth as determined by laparoscopic sonography was 93 per cent. Laparotomy was avoided in 19 per cent of patients and the preoperative stage was changed in 41 per cent. Laparoscopy including ultrasonography was effective in staging pancreatic head malignancy.

Humans↗
PubMed1995

Current applicability of duplex Doppler ultrasonography in pancreatic head and biliary malignancies.

In most patients with a pancreatic head carcinoma or a cholangiocarcinoma of the liver (Klatskin tumour) US is the first imaging modality. Tumour detection using US can exceed that of CT. For small tumours, endosonography or ERCP is recommended. Enlarged lymph nodes are not a major diagnostic parameter, because a reliable differentiation between reactive and malignant lymph nodes is generally not possible. Very tiny liver and peritoneal metastases are missed by the current imaging modalities including US and only detectable by laparoscopy and/or laparoscopic US. Tumour involvement of the portal venous system is an important determinant for irresectability which can often be assessed by duplex Doppler US obviating invasive or expensive imaging modalities. In pancreatic head carcinoma an abnormal pulsed Doppler signal is highly suspicious for involvement of the portal venous system. However, a normal pulsed Doppler signal does not exclude involvement at all. In Klatskin tumour, Doppler US had an accuracy of 91% compared with surgical findings in predicting portal venous involvement. In most cases of pancreatic head carcinoma or Klatskin tumour, US can assess irresectability. However, assessment of curative resectability in these tumours remains a problem.

Bile Duct Neoplasms↗
PubMed1995

Reduction in goiter size by 131I therapy in patients with non-toxic multinodular goiter.

A retrospective follow-up study of 131I treatment was performed in 10 females (median age 48 years, range 40-74 years) with non-toxic multinodular goiter. The median dose of 131I given was 20 mCi (range 14-65 mCi). Thyroid volume was measured by ultrasonography. The median follow-up period was 26 months (range 12-68 months). Nine patients had a reduction of goiter size: thyroid volume decreased from 88 +/- 14.9 ml (mean +/- SEM) to 49 +/- 10.9 ml 1 year after 131I treatment. The relative decrease of goiter size was 48% after 1 year (N = 9) and 59% after 2 years (N = 5). One patient did not respond and was referred for operation. Side effects were mild spontaneously resolving radiation thyroiditis in one patient and subclinical hypothroidism in four patients. In conclusion, 131I treatment of non-toxic goiter is an effective treatment at the expense of post-radiation (subclinical) hypothyroidism.

Aged↗
PubMed1995

Laparoscopy and laparoscopic ultrasonography in staging of carcinoma of the esophagus and gastric cardia.

BACKGROUND: The objective of this prospective study was to assess the contribution of laparoscopy combined with laparoscopic ultrasonography (LLU) in the preoperative staging of patients with carcinoma of the esophagus and cardia. STUDY DESIGN: Preoperative LLU was performed in 56 patients who were selected for curative resection of carcinoma of the esophagus (n = 38) or gastric cardia with involvement of the distal esophagus (n = 18) after routine preoperative workup. During LLU, the peritoneal cavity was scrutinized for metastatic disease, and ultrasonography of the liver and celiac axis was performed. In all patients without histologically proven metastases, laparotomy was then performed. RESULTS: The morbidity rate of the procedure was 3.5 percent (two superficial wound infections). In three (5 percent) of the 56 patients, laparotomy was excluded by the presence of intra-abdominal metastases. In three other patients, laparotomy was necessary to confirm the suspected hepatic or peritoneal metastases, or both, because histologic proof was not obtained at laparoscopy. In one patient, LLU failed to detect a small hepatic metastasis in segment VII. The preoperative stage was altered by laparoscopy in nine (17 percent) patients (M1 in six, T4 in three). Laparotomy was avoided in two (11 percent) and the preoperative stage changed in seven patients (41 percent), all of whom had carcinoma of the gastric cardia, as occurred in one (3 percent) and two (6 percent) patients with middle and distal carcinoma of the esophagus, respectively. CONCLUSIONS: Preoperative staging by LLU is of little value in patients with carcinoma of the middle and lower esophagus. The probable role of LLU in the staging of patients with carcinomas of the gastric cardia remains to be confirmed in larger series.

Cardia↗
PubMed1994

The evolution of renal angiomyolipomas in patients with tuberous sclerosis.

In 1986, 23 patients with renal angiomyolipomas as part of tuberous sclerosis were assessed by ultrasonography. In 1991, 20 patients in this group were reexamined with special attention paid to the renal pathological condition. Ultrasonography was performed by the same radiologist who performed the examination in 1986. Of 20 patients 7 had severe hemorrhage necessitating hospital admission (5 had a renal lesion larger than 3.5 cm. in diameter). In 2 patients the exact diameter of the renal angiomyolipomas could not be determined and they underwent nephrectomy. Three patients underwent successful selective embolization of the bleeding angiomyolipoma. One patient died. The hemorrhage resolved spontaneously in 1 patient and treatment was not feasible. In 4 patients the lesions increased in size between 1986 and 1991. Based on these results there is a relationship between the size of the angiomyolipomas and the risk of bleeding. Renal angiomyolipomas larger than 3.5 cm. in diameter have a substantial risk for severe hemorrhage. Some angiomyolipomas show progression. Periodic followup is mandatory every 6 months. For angiomyolipomas larger than 3.5 cm. in diameter an aggressive approach is advised. Selective embolization is the initial method of choice.

Adult↗
PubMed1994

Thyroid function and thyroid size in normal pregnant women living in an iodine replete area.

OBJECTIVE: The interpretation of the changes in thyroid hormone concentrations during normal pregnancy is a matter of debate involving, in some geographical regions, enhanced thyroid activity in early pregnancy and a hypothyroid state in the third trimester. A clinically detectable increase in thyroid size has been found in areas of mild iodine deficiency ('goitre of pregnancy'), but not in iodine replete areas. DESIGN: A prospective study. We have studied thyroid size and function in normal pregnant women living in an iodine replete area. PATIENTS: Healthy women before and during a normal pregnancy resulting from artificial insemination (n = 10) and other women during the normal menstrual cycle (n = 11), in the iodine replete area of Amsterdam. MEASUREMENTS: Thyroid volume was measured by ultrasonography. Plasma T4, free T3, free reverse T3, TSH, thyroxine binding globulin, hCG, progesterone and thyroid autoantibodies were measured. RESULTS: Thyroid volume did not change during pregnancy (data given before pregnancy and during 1st, 2nd and 3rd trimesters, respectively: 10.3 +/- 5.1, 10.6 +/- 4.4, 9.6 +/- 3.8 and 9.4 +/- 3.0 ml, NS). Free T4 and free T3 levels declined during pregnancy (13.7 +/- 2.0, 13.5 +/- 4.1, 11.2 +/- 2.8, 10.2 +/- 1.6 pmol/l, P = 0.005; 4.55 +/- 0.63, 4.64 +/- 0.88, 3.72 +/- 0.67 and 4.01 +/- 0.75 pmol/l, P = 0.003), whereas free reverse T3 levels increased during pregnancy (0.16 +/- 0.04, 0.19 +/- 0.07, 0.14 +/- 0.03 and 0.20 +/- 0.07 pmol/l, P = 0.001). Thyroglobulin levels remained unchanged. Thyroid hormones and thyroid volume did not differ between follicular and luteal phases of the menstrual cycle. CONCLUSION: Thyroid volume does not increase during pregnancy in iodine-replete areas. The decrease in free T4 and free T3 and the increase in free reverse T3 concentrations during pregnancy resemble the changes in thyroid hormones seen in non-thyroidal illness. This could be a physiological adaptation enabling energy conservation during the high metabolic demands of pregnancy.

Environment↗
PubMed1993

[Doppler echography for the preoperative assessment of malignant processes in the pancreas head and liver hilus].

Ultrasound is the imaging technique of choice in obstructive jaundice for demonstration of dilatation of the bile ducts, and its position and cause. In carcinoma of the pancreatic head and in hilar tumours of the liver (Klatskin) it is often possible to demonstrate their inoperability, making other imaging techniques unnecessary. Duplex-Doppler ultrasound can be highly advantageous in the evaluation of compression or invasive growth of the tumour in the mesenterico-portal venous system, making such invasive examination procedures as angiography unnecessary.

Bile Duct Neoplasms↗
PubMed1992

Benign fibrosing disease at the hepatic confluence mimicking Klatskin tumors.

BACKGROUND: Hilar obstructions remain a challenge with regard to diagnosis and treatment. METHODS: In the period from 1984 to 1990, 82 patients underwent resective surgery under the presumptive diagnosis of hilar cholangiocarcinoma (Klatskin tumor). The diagnosis was based on the combined appearances on direct cholangiography and ultrasonography in all cases, with the use of various other imaging modalities in some cases. RESULTS: The perioperative findings from an experienced surgical team were usually thought to be compatible with bile duct carcinoma. However, histologic examination of the resected specimens revealed benign fibrosing or localized sclerosing lesions in 11 patients (13.4%). CONCLUSIONS: The current state of diagnostic imaging fails as yet to discriminate reliably between benign and malignant hilar lesions. Whereas the immediate therapeutic consequences may be equal (resection followed by hepaticojejunostomy), the late consequences differ in a major way because benign disease has a much better prognosis. In the presence of suspicious hilar obstruction, operable lesions should not be treated by "palliative" intubational techniques and radiation therapy without a firm diagnosis of malignancy. However, overtreatment (extended liver resection, vascular reconstruction, and liver transplantation) should be avoided as well when a benign lesion has not been ruled out.

Adenoma, Bile Duct↗
PubMed1991

[Pneumocystis carinii infection during prophylaxis with nebulized pentamidine in a patient with AIDS].

Since the introduction of aerosolised pentamidine for prophylaxis against Pneumocystis carinii pneumonia (PCP) in HIV-seropositive persons and patients with AIDS, an increasing number of cases of atypical manifestations of infection with Pneumocystis carinii have been reported in the United States, viz. upper lobe pneumonia, extrapulmonary Pneumocystis carinii infection and spontaneous pneumothorax. An association between these atypical manifestations of Pneumocystis carinii infection and the use of aerosolised pentamidine seems likely. This report is the first description in the Netherlands of an atypical Pneumocystis carinii infection in an AIDS patient while using aerosolised pentamidine for prophylaxis against PCP. Since aerosolised pentamidine for prophylaxis against PCP is increasingly being used in the Netherlands, a rise in incidence of atypical manifestations of Pneumocystis carinii infection can be expected.

Acquired Immunodeficiency Syndrome↗