The nose is a primary point of entry for air to get into the lungs. As this air enters, it is important that its temperature is adjusted for optimum gas transfer in the lungs. This adjustment is achieved via heat exchange between the air and the blood being supplied to the nasal cavity. This is one of the primary reasons for the relatively large blood supply to the nasal cavity. Kiesselbach’s plexus is an integral anastomosis of five branches converging in the anterior inferior quadrant of the nasal septum (over the septal cartilage). The area has been referred to as Little’s Area, Kiesselbach’s Triangle or Kiesselbach’s Area. Little’s area is a common site of epistaxis (nose bleeds) in both paediatric and adult cases.
Branches of the Anastomosis
Branching from the maxillary artery, the sphenopalatine artery enters the nasal cavity via the sphenopalatine foramen and supplies the septal wall of the cavity. Entering through the orbit, the septal branches of the anterior and posterior ethmoidal arteries (branches of the ophthalmic artery) gives supply to the roof as well as the septal wall of the cavity as it travels to Little’s area. The facial artery gives off the superior labial artery; the septal branch of which enters the nasal cavity through the nares and joins the anastomoses in Little’s area. The greater palatine artery, a terminal branch of the maxillary artery, passes through the greater palatine foramen and travels along the hard palate to enter the nasal cavity by way of the incisive canal, thus joining the anastomosis in Kiesselbach’s area.
Therefore, Little’s area – and the nasal cavity in general – receives arterial supply from both the external (greater palatine, sphenopalatine and superior labial arteries) and the internal (anterior and posterior ethmoidal arteries) carotid arteries. For completion, the blood supply to this area is drained by accompanying veins. The deoxygenated blood is returned to systemic circulation via the facial vein, ophthalmic veins, and pterygoid plexus.
Epistaxis, or nose bleeds, is the most common pathological processes associated with Little’s area. While the exact aetiology remains elusive, there are several conditions that may precipitate nasal bleeding. Some cases have been described as spontaneous. These are usually precipitated by trauma or an underlying infection and most often occur at Little’s area. Spontaneous nose bleeds are most often seen in young adults and children. Alternatively, epistaxis may occur without external trauma and originate in the superior posterior region of the nasal cavity. This is often referred to as hypertensive epistaxis and is more prevalent in individuals in the older age groups.
Spontaneous epistaxis is more likely to recur than hypertensive epistaxis. However, it is significantly easier to treat. Nose bleeds from Little’s area are best controlled by vascular compression (pressing down the ala on the septum). In a clinical setting, packing the affected cavity with cotton wool treated with phenylepherine and lidocaine can control the bleeding if left for about 10 minutes. In extreme cases, where bleeding is persistent, cauterization of the vessels (under local anaesthetic for compliant adults or general anaesthetic for children) is a suitable option for management of the bleeding.