Acute appendicitis is one of the most common surgical emergencies globally, with a lifetime incidence of 8.6% in men and 6.7% in women. While acute appendicitis should be managed promptly to reduce the morbidity associated with perforated appendicitis, morbidity from negative appendicectomy is similar to morbidity from uncomplicated appendicitis. Computer tomography is widely used to aid in the diagnosis of acute appendicitis, however, is costly, often has a slow turn around time, and is associated with exposure to ionising radiation. In contrast, ultrasound is cheap, widely available, requires minimal patient preparation, and does not require exposure to ionising radiation. Ultrasonography is becoming increasingly used for adult patients in emergency settings. The literature has estimated the sensitivity of ultrasound for acute appendicitis in adult patients as between 39-96.4%. The sensitivity and specificity of ultrasound for the diagnosis of acute appendicitis is significantly increased when the appendix is visualised. In cases of a non visualised appendix, indirect ultrasound signs can improve the sensitivity to 93.9% and specificity to 85.7%. The variation in sensitivity and specificity for ultrasound in the diagnosis of acute appendicitis in adults may be due to multiple factors. Ultrasonographer experience, a retrocaecal appendix and obesity have all been described. Given the availability, cost and potential to reduce the rate of negative appendicectomy, ultrasound should be considered as the first line imaging modality for adult patients presenting with suspected AA.

Computer tomography colonography (CTC) is an increasingly utilized diagnostic modality in Australia. CTC aims to image the entire colon, and is often used in higher risk patient populations. Colonic perforation following CTC is a rare complication, with only 0.008% of patients undergoing CTC requiring surgical intervention. Most published cases of perforation following CTC are due to identifiable causes, often involving the left colon or rectum. We present a rare case of caecal perforation following CTC, requiring right hemicolectomy. This report highlights the need for high suspicion for CTC complications, despite their rarity, and the utility of diagnostic laparoscopy for diagnosis in atypical presentations.

Rectal malignant tumours may have an unexpected histologyColorectal lymphoma (CRL) commonly affects males from age 50 to 70, 1 and is associated with inflammatory bowel disease, coeliac disease and immunosuppression. 2 Primary rectal lymphoma (PRL) is rare and accounts for 0.05% of all primary rectal malignancies. 3 It is a form of extranodal lymphoma originating from solid organs. While the gastrointestinal (GI) tract is the most common site of extranodal lymphoma, lymphoma of the colon and rectum account for less than 10% of all GI lymphomas. 1 We present a