# Ultrasound Animal Challenge Halloween Special – Answer

## Metadata
- Content type: Blog
- Canonical URL: https://123sonography.com/blog/ultrasound-animal-challenge-halloween-special-answer
- Published: October 31, 2022

## Overview
The answer to our question "What pathology of the lung resembles a ‘spider web’ on ultrasound?"

## Authors
- [Univ. Prof. Dr. Thomas Binder](/speaker/146) - Medical University of Vienna and founder/CMO 123Sonography, Webinar Moderation

## Content
###

The answer to our question "[What pathology of the lung resembles a ‘spider web’ on ultrasound?](https://123sonography.com/ultrasound-animal-challenge-halloween-spider-sign)" is:

## C) A form of complex pleural effusion

[ ![](https://123sonography.com/sites/default/files/styles/video_thumbnail/public/video/images/us-animal-challenge-spider-sign-preview.png?itok=l5TM03_O "us-animal-challenge-spider-sign-preview.png") ](https://vimeo.com/765659240/28d16a801e&title=0&byline=0&portrait=0)

Generally, pleural effusion often presents as a hypo- or anechoic collection of fluid between the visceral and parietal pleura. However, a complex pleural effusion may appear homogeneous or heterogeneously echogenic. In this case, of a patient with staphylococcal pneumonia we are looking at a septated complex pleural effusion. You can see fibrin strands (thin hyperechoic lines) within the fluid collection. The loculations resemble a "spider web”.

**Yours,
Thomas Binder and the 123sonography team**

PS: If you missed the previous Animal Challenge posts you can always visit our “zoo”:

- [Tiger-stripe Sign](https://123sonography.com/blog/ultrasound-animal-challenge-1-%E2%80%93-what-tiger-stripe-sign)
- [Snake Sign](https://123sonography.com/blog/ultrasound-animal-challenge-2-snake-sign)
- [Tail of a Whale](https://123sonography.com/blog/ultrasound-animal-challenge-3-tail-of-whale)
- [Butterfly Sign](https://123sonography.com/blog/ultrasound-animal-challenge-4-butterfly-sign)
- [Bunny Sign](https://123sonography.com/blog/ultrasound-animal-challenge-5-bunny-sign)