Normal splenic volumes estimated using three-dimensional ultrasonography

Near-total splenectomy for hereditary spherocytosis: clinical prospects in relation to disease severity

We prospectively studied the efficacy of near total splenectomy (NTS) for managing hereditary spherocytosis (HS) based on haemoglobin (Hb), total bilirubin and splenic remnant regrowth in 30 children receiving NTS for HS between November 1996 and December 2004 (mean followup 3.6 years). Patients were classified into three severity groups. At followup, mean Hb had increased by 2.9-5.0 g/dl (P = 0.110) and bilirubin dropped by 15.4-56.4 mumol/l. Remnant regrowth was moderate, within the weight-specific norm. Amongst spleen-preserving techniques, NTS shows markedly lower rates of recurrent haemolysis, remnant regrowth and secondary operations, thus potentially benefiting all clinical forms of HS.

Hydronephrotic kidney: pediatric three-dimensional US for relative renal size assessment--initial experience

PURPOSE

To prospectively evaluate accuracy of three-dimensional (3D) ultrasonography (US) for assessment of relative renal size in infants and children with hydronephrosis.

MATERIALS AND METHODS

Informed consent was obtained from parents and also from children who were older than 8 years. Study was approved by ethics committee. Two-dimensional (2D) US, 3D US, and scintigraphy were performed in 40 patients with hydronephrosis (age range, neonate to 16 years; seven girls, 33 boys) without acute renal disease. Twenty patients also underwent magnetic resonance (MR) urography. US and MR urography were performed by one experienced pediatric radiologist; 3D US and MR urographic volume calculations were performed by specifically trained radiologists. Three-dimensional US was performed with integrated 3D volume probes or external system based on electromagnetic positioning devices. At 2D US, kidney volume was calculated with application of ellipsoid equation. At MR urography and 3D US, real renal parenchymal volume was calculated with subtraction of dilated collecting system. Split renal function was assessed with static renal scintigraphy. Three-dimensional US results were graded with respect to image quality and compared with results of 2D US, scintigraphy, and MR urography by using mean difference percentage and standard deviation of the difference. All investigations were performed with blinding. Inter- and intraobserver variability were calculated with coefficient of variation.

RESULTS

In 76 of 80 kidneys, 3D US image of diagnostic quality was obtained. Three-dimensional US volume measurements compared well with MR urographic measurements (mean difference, -2.5% +/- 7.8 [standard deviation] vs 25.8% +/- 32.2 for 2D US) and with scintigraphically assessed split renal function (mean difference, 1.2% +/- 9.2 vs 15.9% +/- 43.8 for 2D US). Intra- and interobserver variability were +/-6.4% and +/-9.9%, respectively.

CONCLUSION

Initial experience with renal 3D US indicates that it is an accurate method for assessment of renal parenchymal volume and relative renal size, provided there is no acute renal disease.

Partial splenectomy before a hematopoietic stem cell transplantation in children

Hematopoietic stem cell (HSC) engraftment is delayed in children with hypersplenism, and splenectomy may improve HSC engraftment. However, the use of total splenectomy in children is limited because of concerns for postsplenectomy sepsis. In this study, the authors sought to assess the role of partial splenectomy for children with hypersplenism undergoing HSC transplantation.

METHODS

Five children with a variety of conditions and associated hypersplenism underwent partial splenectomy before an HSC transplantation at the authors' institution between 2000 and 2003. Primary outcome measures were rates of neutrophil and platelet engraftment. Secondary outcome measures included perioperative complications, splenic regrowth, graft-versus-host disease, and infection rate. All outcomes were compared with recipients of an HSC transplant from both age-matched nonsplenectomized children (n = 497) and hypersplenic children who underwent total splenectomy (n = 10). Outcomes were compared using Wilcoxon's rank sum test.

RESULTS

The rate of both neutrophil and platelet engraftment was faster in children who underwent either partial or total splenectomy as compared with nonsplenectomized children (mean rates of neutrophil engraftment were 26, 19, and 19 days for the nonsplenectomy, total splenectomy, and partial splenectomy groups, respectively; mean rates of platelet engraftment were 97, 37, and 45 days for the nonsplenectomy, total splenectomy, and partial splenectomy groups, respectively). Graft-versus-host disease rates were similar between the 3 groups. The mean percentage of splenic regrowth after partial splenectomy was 39%. There were no perioperative complications.

CONCLUSIONS

Partial splenectomy may be safely performed before HSC transplantation and, similar to total splenectomy, may improve the rate of HSC engraftment. Although this series has a limited number of patients, the use of partial splenectomy appears to be safe and may allow for splenic salvage to minimize the risk of postsplenectomy sepsis.

Near-total splenectomy: a new technique for the management of hereditary spherocytosis

OBJECTIVE

The authors used a new surgical technique of near-total splenectomy (NTS) and report their experience.

SUMMARY BACKGROUND DATA

Total splenectomy is indicated for the management of patients with hereditary spherocytosis but may be complicated by severe infections and thromboembolic events. Studies have shown that partial or subtotal parenchymal resections can lead to excessive regeneration of the residual parenchyma. The resulting onset of hemolysis requires total splenectomy in a significant portion of patients. Our hypothesis was that a more radical approach to open resection permanently decreases recurrent hemolysis while potentially ensuring immune function.

METHODS

This longitudinal cohort study included 42 patients with moderate to severe hereditary spherocytosis who underwent NTS according to an open procedure developed by the authors. The end criterion was to conserve a remnant spleen of 10 cm in size.

RESULTS

Patient age ranged between 2 and 42 years. Mean resected spleen weight was 580 g; mean remnant volume was 10 cm (range, 8-11 cm). A surgical complication (loss of spleen) occurred in 1 patient. Six-month to 6-year follow-up data was available on 22 patients; 21 of 22 showed preserved phagocytosis and normal blood circulation of the remnant; 1 of 22 experienced secondary remnant necrosis. On average, the remnant spleen grew back to four and a half times its postoperative size. No patients required transfusions, developed gallstones, or symptomatic hemolysis.

CONCLUSIONS

This new technique of NTS is safe, effective, and can minimize the late sequelae of secondary splenectomy.

Sonographic Evaluation of Spleen Size in Tall Healthy Athletes

OBJECTIVE

The purpose of this study was to establish the range of spleen sizes in tall healthy athletes.

SUBJECTS AND METHODS

Sonographic measurements of spleen size and left renal length were performed on 129 college athletes (82 men, 47 women). Length, width, and thickness of the spleen and left renal length were obtained. In addition, the height, weight, and age of each athlete were recorded. Pearson's product moment correlation coefficients were calculated, and linear regression analysis was used to create a model for calculating normative values.

RESULTS

The mean body height for men was 74.3 (189 cm) +/-(SD) 3.7 inches (9 cm) and for women was 69.3 (176 cm) +/- 3.7 inches (9 cm). Spleen length was greater than 12 cm in 31.7% of the men (mean spleen length, 11.4 +/- 1.7 cm) and in 12.8% of the women (mean spleen length, 10.3 +/- 1.3 cm). In women, height correlated with spleen length (r = 0.3, p = 0.05), width (r = 0.4, p = 0.01), and volume (r = 0.3, p = 0.02) but not with thickness (r = 0.08, p = 0.6). Spleen length did correlate with left renal length (r = 0.5, p = 0.0005). In men, height correlated with spleen length (r = 0.4, p = 0.0003), width (r = 0.5, p = 0.0001), and volume (r = 0.4, p = 0.0002) and less with thickness (r = 0.3, p = 0.01). Spleen length and left renal length were poorly correlated (r = 0.2, p = 0.04). Regression analysis showed that in women taller than 5 ft 6 inches (168 cm), the mean splenic length of 10 cm increased by 0.1 cm for each 1-inch incremental increase in height. In men taller than 6 ft (180 cm), the mean splenic length of 11 cm increased by 0.2 cm for each 1-inch incremental increase in height.

CONCLUSION

Spleen size correlates with height in tall healthy athletes. Nomograms from this data can be used to gauge the risk of returning to play after episodes of acute splenomegaly, as with infectious mononucleosis.

The reproducibility and short-term and long-term repeatability of sonographic measurement of splenic length

This study was undertaken to evaluate the reproducibility (interobserver variability), and the short-term and long-term repeatability (intraobserver variability) of sonographic measurement of the maximum and mean splenic length. Ultrasound (US) measurements of the splenic length were performed in 43 subjects, ages 30 to 59 years old (mean age = 44.5 years). Each subject attended three US sessions: baseline examination and 30 min and 8 weeks after the baseline examination. In each session, US examinations of the spleen were performed and the splenic length was measured by four operators. In each examination, the splenic length was measured 3 times, and the maximum and mean values were obtained. The overall reproducibility of the measurements of maximum and mean splenic lengths were 67% and 89%, respectively. The short-term repeatability in measuring the maximum and mean splenic lengths were 87% and 94%, respectively, whereas the long-term repeatabilities were 61% and 76%, respectively. The reproducibility and short-term and long-term repeatability of the measurement of mean splenic length were higher than those of the maximum splenic length. In the mean and maximum splenic length measurement, the short-term repeatability was higher than the long-term repeatability. The results suggested that the mean splenic length has a higher reliability in sonographic measurement and should be used in routine clinical practice. Measurement errors should be considered when evaluating the changes of splenic length in serial US examinations, particularly in long-term follow-up.

Aspectos morfológicos e hemodinâmicos do baço em indivíduos normais: estudo por ultra-som Doppler

ANTECEDENTES: A diversidade de técnicas de mensuração esplênica pelo ultra-som Doppler (US Doppler), a falta de valores biométricos e dopplervelocimétricos dificultam a avaliação deste órgão e de suas características hemodinâmicas. OBJETIVO: Estabelecer padrões biométricos e hemodinâmicos por US-Doppler em indivíduos adultos sadios. MATERIAIS E MÉTODOS: Estudo prospectivo de 44 indivíduos sadios, sendo 19 do sexo masculino e 25 do sexo feminino, na faixa etária de 23 a 60 anos (37,4 ± 9,6). Morfometria (US modo-B): baço: eixos longitudinal (L), transversal (T) e ântero-posterior (AP); diâmetro da artéria esplênica (DAE) e diâmetro da veia esplênica (DVE). Índices morfométricos do baço: uniplanar (IBU), biplanar (IBB) e volume esplênico (VE). Dopplervelocimetria (US Doppler): a) artéria esplênica: velocidade de pico sistólico (VPS), média das velocidades máximas de fluxo (TAMax); índices de impedância vascular: índice de resistividade (IR); índice de pulsatilidade (IP); b) veia esplênica: média das velocidades máximas de fluxo (TAMax). RESULTADOS: Morfometria: L = 9,3 ± 1,3 cm; T= 3,9 ± 0,7 cm; AP = 8,4 ± 1,2 cm; DAE = 0,3 ± 0,07 cm; DVE: 0,5 ± 0,12 cm. Índices morfométricos do baço: IBU = 33,5 ± 9,9; IBB = 36,7 ± 10,3; VE = 164,3 ± 62,9 cm³. Dopplervelocimetria: a) artéria esplênica: VPS = 59,8 ± 23,6 cm/s; TAMax = 40,2 ± 15,9 cm/s; IP = 0,86 ± 0,30; IR = 0,55 ± 0,09; b) veia esplênica: TAMax = 16,8 ± 8,3 cm/s. CONCLUSÃO: Relato de valores biométricos e dopplervelocimétricos do baço em indivíduos sadios.

Clinical and hematologic benefits of partial splenectomy for congenital hemolytic anemias in children

OBJECTIVE

To assess the role of partial splenectomy for symptomatic children with various congenital hemolytic anemias.

SUMMARY BACKGROUND DATA

The use of total splenectomy for symptomatic children with congenital hemolytic anemias is restricted by concern of postsplenectomy sepsis. A partial splenectomy is an alternative procedure, although its utility remains incompletely defined.

METHODS

This longitudinal cohort study followed 25 symptomatic children with various congenital anemias who underwent partial splenectomy. Sixteen children had hereditary spherocytosis (HS), and nine children had other erythrocyte disorders. Outcome measures were clinical and laboratory hemolysis, splenic phagocytic and immune function, and splenic regrowth as measured by ultrasonography. Discrete parameters were compared using the Student test.

RESULTS

Partial splenectomy was successful in all 25 children, with minimal morbidity. Follow-up ranged from 7 months to 6 years (mean 2.3 +/- 1.5 years). Following surgery, children with HS had increased hemoglobin values, decreased reticulocyte and bilirubin levels, and preserved splenic function. Most children without HS had decreased symptoms of hypersplenism and splenic sequestration. Over time, variable rates of splenic regrowth were noted, although regrowth did not necessarily correlate with recurrent hemolysis.

CONCLUSIONS

In children with hereditary spherocytosis, a partial splenectomy appears to control hemolysis while retaining splenic function. In children with other congenital hemolytic anemias, a partial splenectomy appears to control symptoms of hypersplenism and splenic sequestration.

[Late morphologic and hemodynamic changes in the splenic territory of patients with mansoni's hepatosplenic schistosomiasis after distal splenorenal shunt. (Ultrasonography-Doppler study)]

BACKGROUND

The distal splenorenal anastomosis (Warren's operation) has been indicated for the treatment of high digestive bleeding caused by esophagic varices because it would ideally reduce the venous pressure in the cardiotuberositary territory without changing the mesenteric-portal venous flow. However, the changes it produce in the splenic territory have not been fully understood.

AIM

To appraise the late morphologic and hemodynamic changes in the splenic territory produced by the distal splenorenal anastomosis in patients with portal hypertension due to mansoni's hepatosplenic schistosomiasis complicated by esophagic bleeding.

METHOD

Ultrasonography-Doppler study of the splenic region of 52 patients with portal hypertension due to mansoni's schistosomiasis and previous bleeding by esophagic varices. They were divided in two groups: 40 non operated upon and 12 with a distal splenorerenal anastomosis. The following parameters and indices were compared between the two groups: a) morphometric parameters (splenic artery and vein's diameter, splenic diameters (longitudinal, transversal and antero-posterior); b) velocimetric parameters of the splenic vessels (systolic peak velocity in the splenic artery, mean flow velocity in the splenic vein; c) biometric index of the spleen (longitudinal x transversal); volumetric index of the spleen (longitudinal x transversal x antero-posterior x 0,523); hemodynamic indices of the splenic artery's impedance: pulsatility and resistivity.

RESULTS

The patients with distal splenorenal anastomosis showed: a) reduction in splenic indices: volumetric (non operated 903,83 +/- 452, 77 cm / distal splenorenal anastomosis 482,32 +/- 208,02 cm (46,64%)) and biometric (non operated 138,14 +/- 51,89 cm /distal splenorenal anastomosis 94,83 +/- 39,83 cm (33,35%)); b) no change: splenic artery's diameter (non operated 0,57 +/- 0,16 cm/distal splenorenal anastomosis 0,57 +/- 0,23 cm); velocity in the splenic artery non operated 107 +/- 42,02 cm/seg/distal splenorenal anastomosis 89,81 +/- 41,20 cm/seg), resistivity (non operated 0,58 +/- 0,008/distal splenorenal anastomosis 0,56 +/- 0,06) and pulsatility (non operated 0,91 +/- 0,19/distal splenorenal anastomosis 0,86 +/- 0,15, splenic vein (non operated 1,10 +/- 0,30 cm/distal splenorenal anastomosis 1,19 +/- 0,29 cm); c) increase: mean flow velocity in the splenic vein (non operated 20,54 +/- 8,45 cm/seg/distal splenorenal anastomosis 27,83 +/- 9,29 cm/seg).

CONCLUSIONS

The comparison of the ultrasonography Doppler results of the two groups of patient (non operated and distal splenorenal anastomosis) showed that in patients with distal splenorenal anastomosis there was a decrease of the volume of spleen; increase in the mean flow velocity in the splenic vein; no changes in the morphologic and hemodinamyc parameters of the splenic artery neither in its velocimetric indices.

Spleen enlargement in healthy donors during G-CSF mobilization of PBPCs

BACKGROUND

Recombinant human G-CSF is widely used to mobilize PBPCs in healthy donors for allogeneic transplantation. There have been concerns about donor safety because of splenic ruptures during G-CSF application. To address this problem, changes in splenic size in 91 healthy donors during G-CSF mobilization of allogeneic PBPCs were investigated.

STUDY DESIGN AND METHODS

For mobilization, G-CSF in a dosage of 7.5 microg per kg per day was administered for 5 days and PBPC collection started Day 5. Splenic size was determined by ultrasound before G-CSF application was started and on the day of the first apheresis.

RESULTS

The mean increase in splenic length was 11 mm (range, 0-28 mm; p<0.0001), whereas a mean increase of 5 mm in width (range, 0-14 mm; p<0.0001) was measured. No major side effects could be observed. There was no significant correlation between the increase in splenic size and the hematologic values, or the age and body-mass index. In a multivariant analysis, no independent risk factor for the development of a spleen enlargement over 19 mm in length and 9 mm in thickness was found in 20 percent of investigated donors.

CONCLUSION

In this prospective trial, a significant spleen enlargement was observed in healthy donors during G-CSF mobilization of allogeneic PBPCs. Further investigations are needed to define the degree of spleen enlargement with higher G-CSF dosages to improve donor safety.

Ultrasound imaging in three and four dimensions

Three-dimensional (3D) reconstruction of ultrasound images was first demonstrated nearly 15 years ago, but only now is becoming a clinical reality. In the meantime, methods for 3D reconstruction of CT and MRI images have achieved an advanced state of development, and 3D imaging with these modalities has been applied widely in clinical practice. 3D applications in ultrasound have lagged behind CT and MRI, because ultrasound data is much more difficult to render in 3D, for a variety of technical reasons, than either CT or MRI data. Only in the past few years has the computing power of ultrasound equipment reached a level adequate enough for the complex signal processing tasks needed to render ultrasound data in three dimensions. At this point in time, the clinical application of 3D ultrasound is likely to advance rapidly, as improved 3D rendering technology becomes more widely available. This article is a review of the present status of 3D ultrasound imaging. It begins by comparing the characteristics of CT, MRI, and ultrasound image data that either make these data amenable or not amenable to 3D reconstruction. The article then considers the technical features involved with acquiring an ultrasound 3D data set and the mechanisms for reconstructing the images. Finally, the article reviews the literature that is available regarding clinical application of 3D ultrasound in obstetrics, ultrasound, the abdomen, and blood vessels.