Clinical trial NCT05050994: Ultrasound Guided Microwave Ablation of Splenomegaly in Children
Official title: Ultrasound Guided Partial Microwave Ablation of the Spleen Due to Secondary Splenomegaly in Children - a Study of Feasibility and Acceptability
Study type: INTERVENTIONAL
Overall status: UNKNOWN
Phase: NA
Conditions: Splenomegaly; Congestive, Chronic
Panhematopenia; Splenic
Portal Hypertension
Keywords: Microwave ablation
Lead sponsor: Karolinska Institutet
Sponsor class: OTHER
First posted: 2021-09-21
Enrollment: 10
Sex: ALL
Minimum age (years): 10
Maximum age (years): 17
Standard ages: CHILD
Accepts healthy volunteers: no
Allocation: NA
Intervention model: SINGLE_GROUP
Intervention model description: Prospective observational pilot trial
Primary purpose: TREATMENT

Brief summary: Children with liver cirrhosis frequently develops portal hypertension. One of the serious complications to portal hypertension is splenomegaly, which may result in pancytopenia, especially thrombocytopenia that may cause bleeding tendencies.

Symptomatic splenomegaly is often treated with partial splenic embolization (PSE). PSE is effective but may give rise to postembolization syndrome not well tolerated in the pediatric population. In adults, microwave ablation (MWA) has been used to treat splenomegaly with promising results but with less post-operative pain. Our study is a pilot trial to evaluate the feasibility and acceptability of this treatment in children.

Detailed description: The ablation will be performed under general anesthesia by an experienced interventional radiologist. Ultrasound will be used for peri-operative assessment and the microwave antenna will be inserted under ultrasound guidance focusing on the middle to inferior part of the spleen to avoid harm to the diaphragm. After the emission of microwaves for up to 5 minutes, the antenna will be pulled back and the emission will be repeated until the ablation zone is approximately 1 cm from the splenic surface. In this way, two or three overlapping areas will be ablated with every insertion of the antenna. The ablation zones will be visible as hyperechoic areas on b-mode ultrasound during operation, and the goal is to ablate up to 40-50% of the total volume of the spleen (as estimated by the radiologist). If the ablated volume is less than 40-50% at follow up, the procedure can be repeated in a second session for additional effect.

Eligibility criteria: Inclusion Criteria:

* Spleen length \> +2 standard deviations of normal limit
* Platelet count below 30-35 x 109 cells/L and a history of bleeding tendencies
* Symptoms of portal hypertension such as splenomegaly, thrombocytopenia, leucopenia, ascites, esophageal or gastric varices, hypertensive gastropathy, anal hemorrhoids and increased portal scintigraphy index, where alternative methods have not been enough or suitable
* A necessity for reduction of splenic volume due to splenic inhibition of motion and activity in the child

Exclusion Criteria:

* Age younger than 10 or older than 17 years of age
* Legal guardians or child do not give consent
* Ongoing infection

Primary outcomes:
measure: Platelet count
timeFrame: Base line and 1, 3, 6 and 12 months follow up
Secondary outcomes:
measure: Number of MWA
timeFrame: Within 12 months
measure: Effect on blood cell count
timeFrame: Base line and 1, 3, 6 and 12 months follow up
measure: Effect on liver function
timeFrame: Base line and 1, 3, 6 and 12 months follow up
measure: Effect on coagulation
timeFrame: Base line and 1, 3, 6 and 12 months follow up
measure: Maximal pain
timeFrame: Day of surgury and the following 7 days
measure: Use of analgesic drugs
timeFrame: Day of surgury and the following 7 days
measure: Days of hospitalization
timeFrame: 1 month
measure: Acceptability of treatment
timeFrame: 1 month after ablation
Other outcomes:
Locations:
city: Stockholm
country: Sweden
facility: Karolinska University Hospital
Study officials:
affiliation: Karolinska Institutet
name: Thomas Casswell, MD, PhD
role: PRINCIPAL_INVESTIGATOR
References: